mirror of
https://github.com/ceph/ceph-csi.git
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e5d9b68d36
Bumps the golang-dependencies group with 1 update: [golang.org/x/crypto](https://github.com/golang/crypto). Updates `golang.org/x/crypto` from 0.16.0 to 0.17.0 - [Commits](https://github.com/golang/crypto/compare/v0.16.0...v0.17.0) --- updated-dependencies: - dependency-name: golang.org/x/crypto dependency-type: direct:production update-type: version-update:semver-minor dependency-group: golang-dependencies ... Signed-off-by: dependabot[bot] <support@github.com>
1338 lines
40 KiB
Go
1338 lines
40 KiB
Go
// Copyright 2019 Google LLC
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package interpreter
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import (
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"fmt"
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"strings"
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"github.com/google/cel-go/common/containers"
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"github.com/google/cel-go/common/types"
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"github.com/google/cel-go/common/types/ref"
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"github.com/google/cel-go/common/types/traits"
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)
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// AttributeFactory provides methods creating Attribute and Qualifier values.
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type AttributeFactory interface {
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// AbsoluteAttribute creates an attribute that refers to a top-level variable name.
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//
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// Checked expressions generate absolute attribute with a single name.
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// Parse-only expressions may have more than one possible absolute identifier when the
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// expression is created within a container, e.g. package or namespace.
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//
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// When there is more than one name supplied to the AbsoluteAttribute call, the names
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// must be in CEL's namespace resolution order. The name arguments provided here are
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// returned in the same order as they were provided by the NamespacedAttribute
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// CandidateVariableNames method.
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AbsoluteAttribute(id int64, names ...string) NamespacedAttribute
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// ConditionalAttribute creates an attribute with two Attribute branches, where the Attribute
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// that is resolved depends on the boolean evaluation of the input 'expr'.
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ConditionalAttribute(id int64, expr Interpretable, t, f Attribute) Attribute
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// MaybeAttribute creates an attribute that refers to either a field selection or a namespaced
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// variable name.
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//
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// Only expressions which have not been type-checked may generate oneof attributes.
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MaybeAttribute(id int64, name string) Attribute
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// RelativeAttribute creates an attribute whose value is a qualification of a dynamic
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// computation rather than a static variable reference.
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RelativeAttribute(id int64, operand Interpretable) Attribute
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// NewQualifier creates a qualifier on the target object with a given value.
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//
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// The 'val' may be an Attribute or any proto-supported map key type: bool, int, string, uint.
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//
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// The qualifier may consider the object type being qualified, if present. If absent, the
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// qualification should be considered dynamic and the qualification should still work, though
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// it may be sub-optimal.
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NewQualifier(objType *types.Type, qualID int64, val any, opt bool) (Qualifier, error)
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}
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// Qualifier marker interface for designating different qualifier values and where they appear
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// within field selections and index call expressions (`_[_]`).
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type Qualifier interface {
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// ID where the qualifier appears within an expression.
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ID() int64
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// IsOptional specifies whether the qualifier is optional.
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// Instead of a direct qualification, an optional qualifier will be resolved via QualifyIfPresent
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// rather than Qualify. A non-optional qualifier may also be resolved through QualifyIfPresent if
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// the object to qualify is itself optional.
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IsOptional() bool
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// Qualify performs a qualification, e.g. field selection, on the input object and returns
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// the value of the access and whether the value was set. A non-nil value with a false presence
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// test result indicates that the value being returned is the default value.
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Qualify(vars Activation, obj any) (any, error)
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// QualifyIfPresent qualifies the object if the qualifier is declared or defined on the object.
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// The 'presenceOnly' flag indicates that the value is not necessary, just a boolean status as
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// to whether the qualifier is present.
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QualifyIfPresent(vars Activation, obj any, presenceOnly bool) (any, bool, error)
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}
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// ConstantQualifier interface embeds the Qualifier interface and provides an option to inspect the
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// qualifier's constant value.
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//
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// Non-constant qualifiers are of Attribute type.
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type ConstantQualifier interface {
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Qualifier
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// Value returns the constant value associated with the qualifier.
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Value() ref.Val
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}
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// Attribute values are a variable or value with an optional set of qualifiers, such as field, key,
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// or index accesses.
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type Attribute interface {
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Qualifier
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// AddQualifier adds a qualifier on the Attribute or error if the qualification is not a valid qualifier type.
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AddQualifier(Qualifier) (Attribute, error)
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// Resolve returns the value of the Attribute and whether it was present given an Activation.
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// For objects which support safe traversal, the value may be non-nil and the presence flag be false.
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//
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// If an error is encountered during attribute resolution, it will be returned immediately.
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// If the attribute cannot be resolved within the Activation, the result must be: `nil`, `error`
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// with the error indicating which variable was missing.
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Resolve(Activation) (any, error)
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}
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// NamespacedAttribute values are a variable within a namespace, and an optional set of qualifiers
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// such as field, key, or index accesses.
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type NamespacedAttribute interface {
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Attribute
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// CandidateVariableNames returns the possible namespaced variable names for this Attribute in
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// the CEL namespace resolution order.
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CandidateVariableNames() []string
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// Qualifiers returns the list of qualifiers associated with the Attribute.
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Qualifiers() []Qualifier
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}
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// NewAttributeFactory returns a default AttributeFactory which is produces Attribute values
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// capable of resolving types by simple names and qualify the values using the supported qualifier
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// types: bool, int, string, and uint.
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func NewAttributeFactory(cont *containers.Container, a types.Adapter, p types.Provider) AttributeFactory {
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return &attrFactory{
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container: cont,
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adapter: a,
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provider: p,
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}
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}
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type attrFactory struct {
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container *containers.Container
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adapter types.Adapter
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provider types.Provider
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}
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// AbsoluteAttribute refers to a variable value and an optional qualifier path.
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//
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// The namespaceNames represent the names the variable could have based on namespace
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// resolution rules.
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func (r *attrFactory) AbsoluteAttribute(id int64, names ...string) NamespacedAttribute {
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return &absoluteAttribute{
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id: id,
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namespaceNames: names,
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qualifiers: []Qualifier{},
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adapter: r.adapter,
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provider: r.provider,
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fac: r,
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}
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}
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// ConditionalAttribute supports the case where an attribute selection may occur on a conditional
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// expression, e.g. (cond ? a : b).c
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func (r *attrFactory) ConditionalAttribute(id int64, expr Interpretable, t, f Attribute) Attribute {
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return &conditionalAttribute{
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id: id,
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expr: expr,
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truthy: t,
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falsy: f,
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adapter: r.adapter,
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fac: r,
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}
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}
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// MaybeAttribute collects variants of unchecked AbsoluteAttribute values which could either be
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// direct variable accesses or some combination of variable access with qualification.
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func (r *attrFactory) MaybeAttribute(id int64, name string) Attribute {
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return &maybeAttribute{
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id: id,
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attrs: []NamespacedAttribute{
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r.AbsoluteAttribute(id, r.container.ResolveCandidateNames(name)...),
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},
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adapter: r.adapter,
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provider: r.provider,
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fac: r,
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}
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}
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// RelativeAttribute refers to an expression and an optional qualifier path.
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func (r *attrFactory) RelativeAttribute(id int64, operand Interpretable) Attribute {
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return &relativeAttribute{
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id: id,
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operand: operand,
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qualifiers: []Qualifier{},
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adapter: r.adapter,
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fac: r,
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}
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}
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// NewQualifier is an implementation of the AttributeFactory interface.
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func (r *attrFactory) NewQualifier(objType *types.Type, qualID int64, val any, opt bool) (Qualifier, error) {
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// Before creating a new qualifier check to see if this is a protobuf message field access.
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// If so, use the precomputed GetFrom qualification method rather than the standard
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// stringQualifier.
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str, isStr := val.(string)
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if isStr && objType != nil && objType.Kind() == types.StructKind {
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ft, found := r.provider.FindStructFieldType(objType.TypeName(), str)
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if found && ft.IsSet != nil && ft.GetFrom != nil {
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return &fieldQualifier{
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id: qualID,
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Name: str,
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FieldType: ft,
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adapter: r.adapter,
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optional: opt,
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}, nil
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}
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}
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return newQualifier(r.adapter, qualID, val, opt)
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}
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type absoluteAttribute struct {
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id int64
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// namespaceNames represent the names the variable could have based on declared container
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// (package) of the expression.
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namespaceNames []string
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qualifiers []Qualifier
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adapter types.Adapter
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provider types.Provider
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fac AttributeFactory
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}
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// ID implements the Attribute interface method.
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func (a *absoluteAttribute) ID() int64 {
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qualCount := len(a.qualifiers)
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if qualCount == 0 {
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return a.id
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}
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return a.qualifiers[qualCount-1].ID()
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}
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// IsOptional returns trivially false for an attribute as the attribute represents a fully
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// qualified variable name. If the attribute is used in an optional manner, then an attrQualifier
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// is created and marks the attribute as optional.
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func (a *absoluteAttribute) IsOptional() bool {
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return false
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}
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// AddQualifier implements the Attribute interface method.
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func (a *absoluteAttribute) AddQualifier(qual Qualifier) (Attribute, error) {
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a.qualifiers = append(a.qualifiers, qual)
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return a, nil
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}
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// CandidateVariableNames implements the NamespaceAttribute interface method.
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func (a *absoluteAttribute) CandidateVariableNames() []string {
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return a.namespaceNames
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}
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// Qualifiers returns the list of Qualifier instances associated with the namespaced attribute.
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func (a *absoluteAttribute) Qualifiers() []Qualifier {
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return a.qualifiers
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}
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// Qualify is an implementation of the Qualifier interface method.
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func (a *absoluteAttribute) Qualify(vars Activation, obj any) (any, error) {
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return attrQualify(a.fac, vars, obj, a)
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}
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// QualifyIfPresent is an implementation of the Qualifier interface method.
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func (a *absoluteAttribute) QualifyIfPresent(vars Activation, obj any, presenceOnly bool) (any, bool, error) {
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return attrQualifyIfPresent(a.fac, vars, obj, a, presenceOnly)
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}
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// String implements the Stringer interface method.
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func (a *absoluteAttribute) String() string {
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return fmt.Sprintf("id: %v, names: %v", a.id, a.namespaceNames)
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}
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// Resolve returns the resolved Attribute value given the Activation, or error if the Attribute
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// variable is not found, or if its Qualifiers cannot be applied successfully.
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//
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// If the variable name cannot be found as an Activation variable or in the TypeProvider as
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// a type, then the result is `nil`, `error` with the error indicating the name of the first
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// variable searched as missing.
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func (a *absoluteAttribute) Resolve(vars Activation) (any, error) {
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for _, nm := range a.namespaceNames {
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// If the variable is found, process it. Otherwise, wait until the checks to
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// determine whether the type is unknown before returning.
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obj, found := vars.ResolveName(nm)
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if found {
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obj, isOpt, err := applyQualifiers(vars, obj, a.qualifiers)
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if err != nil {
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return nil, err
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}
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if isOpt {
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val := a.adapter.NativeToValue(obj)
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if types.IsUnknown(val) {
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return val, nil
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}
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return types.OptionalOf(val), nil
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}
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return obj, nil
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}
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// Attempt to resolve the qualified type name if the name is not a variable identifier.
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typ, found := a.provider.FindIdent(nm)
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if found {
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if len(a.qualifiers) == 0 {
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return typ, nil
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}
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}
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}
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var attrNames strings.Builder
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for i, nm := range a.namespaceNames {
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if i != 0 {
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attrNames.WriteString(", ")
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}
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attrNames.WriteString(nm)
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}
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return nil, missingAttribute(attrNames.String())
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}
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type conditionalAttribute struct {
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id int64
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expr Interpretable
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truthy Attribute
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falsy Attribute
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adapter types.Adapter
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fac AttributeFactory
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}
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// ID is an implementation of the Attribute interface method.
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func (a *conditionalAttribute) ID() int64 {
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// There's a field access after the conditional.
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if a.truthy.ID() == a.falsy.ID() {
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return a.truthy.ID()
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}
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// Otherwise return the conditional id as the consistent id being tracked.
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return a.id
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}
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// IsOptional returns trivially false for an attribute as the attribute represents a fully
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// qualified variable name. If the attribute is used in an optional manner, then an attrQualifier
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// is created and marks the attribute as optional.
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func (a *conditionalAttribute) IsOptional() bool {
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return false
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}
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// AddQualifier appends the same qualifier to both sides of the conditional, in effect managing
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// the qualification of alternate attributes.
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func (a *conditionalAttribute) AddQualifier(qual Qualifier) (Attribute, error) {
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_, err := a.truthy.AddQualifier(qual)
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if err != nil {
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return nil, err
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}
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_, err = a.falsy.AddQualifier(qual)
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if err != nil {
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return nil, err
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}
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return a, nil
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}
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// Qualify is an implementation of the Qualifier interface method.
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func (a *conditionalAttribute) Qualify(vars Activation, obj any) (any, error) {
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return attrQualify(a.fac, vars, obj, a)
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}
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// QualifyIfPresent is an implementation of the Qualifier interface method.
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func (a *conditionalAttribute) QualifyIfPresent(vars Activation, obj any, presenceOnly bool) (any, bool, error) {
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return attrQualifyIfPresent(a.fac, vars, obj, a, presenceOnly)
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}
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// Resolve evaluates the condition, and then resolves the truthy or falsy branch accordingly.
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func (a *conditionalAttribute) Resolve(vars Activation) (any, error) {
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val := a.expr.Eval(vars)
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if val == types.True {
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return a.truthy.Resolve(vars)
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}
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if val == types.False {
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return a.falsy.Resolve(vars)
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}
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if types.IsUnknown(val) {
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return val, nil
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}
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return nil, types.MaybeNoSuchOverloadErr(val).(*types.Err)
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}
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// String is an implementation of the Stringer interface method.
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func (a *conditionalAttribute) String() string {
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return fmt.Sprintf("id: %v, truthy attribute: %v, falsy attribute: %v", a.id, a.truthy, a.falsy)
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}
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type maybeAttribute struct {
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id int64
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attrs []NamespacedAttribute
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adapter types.Adapter
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provider types.Provider
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fac AttributeFactory
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}
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// ID is an implementation of the Attribute interface method.
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func (a *maybeAttribute) ID() int64 {
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return a.attrs[0].ID()
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}
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// IsOptional returns trivially false for an attribute as the attribute represents a fully
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// qualified variable name. If the attribute is used in an optional manner, then an attrQualifier
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// is created and marks the attribute as optional.
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func (a *maybeAttribute) IsOptional() bool {
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return false
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}
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// AddQualifier adds a qualifier to each possible attribute variant, and also creates
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// a new namespaced variable from the qualified value.
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//
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// The algorithm for building the maybe attribute is as follows:
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//
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// 1. Create a maybe attribute from a simple identifier when it occurs in a parsed-only expression
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//
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// mb = MaybeAttribute(<id>, "a")
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//
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// Initializing the maybe attribute creates an absolute attribute internally which includes the
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// possible namespaced names of the attribute. In this example, let's assume we are in namespace
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// 'ns', then the maybe is either one of the following variable names:
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//
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// possible variables names -- ns.a, a
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//
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// 2. Adding a qualifier to the maybe means that the variable name could be a longer qualified
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// name, or a field selection on one of the possible variable names produced earlier:
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//
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// mb.AddQualifier("b")
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//
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// possible variables names -- ns.a.b, a.b
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// possible field selection -- ns.a['b'], a['b']
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//
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// If none of the attributes within the maybe resolves a value, the result is an error.
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func (a *maybeAttribute) AddQualifier(qual Qualifier) (Attribute, error) {
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str := ""
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isStr := false
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cq, isConst := qual.(ConstantQualifier)
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if isConst {
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str, isStr = cq.Value().Value().(string)
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}
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var augmentedNames []string
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// First add the qualifier to all existing attributes in the oneof.
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for _, attr := range a.attrs {
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if isStr && len(attr.Qualifiers()) == 0 {
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candidateVars := attr.CandidateVariableNames()
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augmentedNames = make([]string, len(candidateVars))
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for i, name := range candidateVars {
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augmentedNames[i] = fmt.Sprintf("%s.%s", name, str)
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}
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}
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_, err := attr.AddQualifier(qual)
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if err != nil {
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return nil, err
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}
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}
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// Next, ensure the most specific variable / type reference is searched first.
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if len(augmentedNames) != 0 {
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a.attrs = append([]NamespacedAttribute{a.fac.AbsoluteAttribute(qual.ID(), augmentedNames...)}, a.attrs...)
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}
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return a, nil
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}
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// Qualify is an implementation of the Qualifier interface method.
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func (a *maybeAttribute) Qualify(vars Activation, obj any) (any, error) {
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return attrQualify(a.fac, vars, obj, a)
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}
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// QualifyIfPresent is an implementation of the Qualifier interface method.
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func (a *maybeAttribute) QualifyIfPresent(vars Activation, obj any, presenceOnly bool) (any, bool, error) {
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return attrQualifyIfPresent(a.fac, vars, obj, a, presenceOnly)
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}
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// Resolve follows the variable resolution rules to determine whether the attribute is a variable
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// or a field selection.
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func (a *maybeAttribute) Resolve(vars Activation) (any, error) {
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var maybeErr error
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for _, attr := range a.attrs {
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obj, err := attr.Resolve(vars)
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// Return an error if one is encountered.
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if err != nil {
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resErr, ok := err.(*resolutionError)
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if !ok {
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return nil, err
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}
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// If this was not a missing variable error, return it.
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if !resErr.isMissingAttribute() {
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return nil, err
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}
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// When the variable is missing in a maybe attribute we defer erroring.
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if maybeErr == nil {
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maybeErr = resErr
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}
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// Continue attempting to resolve possible variables.
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continue
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}
|
|
return obj, nil
|
|
}
|
|
// Else, produce a no such attribute error.
|
|
return nil, maybeErr
|
|
}
|
|
|
|
// String is an implementation of the Stringer interface method.
|
|
func (a *maybeAttribute) String() string {
|
|
return fmt.Sprintf("id: %v, attributes: %v", a.id, a.attrs)
|
|
}
|
|
|
|
type relativeAttribute struct {
|
|
id int64
|
|
operand Interpretable
|
|
qualifiers []Qualifier
|
|
adapter types.Adapter
|
|
fac AttributeFactory
|
|
}
|
|
|
|
// ID is an implementation of the Attribute interface method.
|
|
func (a *relativeAttribute) ID() int64 {
|
|
qualCount := len(a.qualifiers)
|
|
if qualCount == 0 {
|
|
return a.id
|
|
}
|
|
return a.qualifiers[qualCount-1].ID()
|
|
}
|
|
|
|
// IsOptional returns trivially false for an attribute as the attribute represents a fully
|
|
// qualified variable name. If the attribute is used in an optional manner, then an attrQualifier
|
|
// is created and marks the attribute as optional.
|
|
func (a *relativeAttribute) IsOptional() bool {
|
|
return false
|
|
}
|
|
|
|
// AddQualifier implements the Attribute interface method.
|
|
func (a *relativeAttribute) AddQualifier(qual Qualifier) (Attribute, error) {
|
|
a.qualifiers = append(a.qualifiers, qual)
|
|
return a, nil
|
|
}
|
|
|
|
// Qualify is an implementation of the Qualifier interface method.
|
|
func (a *relativeAttribute) Qualify(vars Activation, obj any) (any, error) {
|
|
return attrQualify(a.fac, vars, obj, a)
|
|
}
|
|
|
|
// QualifyIfPresent is an implementation of the Qualifier interface method.
|
|
func (a *relativeAttribute) QualifyIfPresent(vars Activation, obj any, presenceOnly bool) (any, bool, error) {
|
|
return attrQualifyIfPresent(a.fac, vars, obj, a, presenceOnly)
|
|
}
|
|
|
|
// Resolve expression value and qualifier relative to the expression result.
|
|
func (a *relativeAttribute) Resolve(vars Activation) (any, error) {
|
|
// First, evaluate the operand.
|
|
v := a.operand.Eval(vars)
|
|
if types.IsError(v) {
|
|
return nil, v.(*types.Err)
|
|
}
|
|
if types.IsUnknown(v) {
|
|
return v, nil
|
|
}
|
|
obj, isOpt, err := applyQualifiers(vars, v, a.qualifiers)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if isOpt {
|
|
val := a.adapter.NativeToValue(obj)
|
|
if types.IsUnknown(val) {
|
|
return val, nil
|
|
}
|
|
return types.OptionalOf(val), nil
|
|
}
|
|
return obj, nil
|
|
}
|
|
|
|
// String is an implementation of the Stringer interface method.
|
|
func (a *relativeAttribute) String() string {
|
|
return fmt.Sprintf("id: %v, operand: %v", a.id, a.operand)
|
|
}
|
|
|
|
func newQualifier(adapter types.Adapter, id int64, v any, opt bool) (Qualifier, error) {
|
|
var qual Qualifier
|
|
switch val := v.(type) {
|
|
case Attribute:
|
|
// Note, attributes are initially identified as non-optional since they represent a top-level
|
|
// field access; however, when used as a relative qualifier, e.g. a[?b.c], then an attrQualifier
|
|
// is created which intercepts the IsOptional check for the attribute in order to return the
|
|
// correct result.
|
|
return &attrQualifier{
|
|
id: id,
|
|
Attribute: val,
|
|
optional: opt,
|
|
}, nil
|
|
case string:
|
|
qual = &stringQualifier{
|
|
id: id,
|
|
value: val,
|
|
celValue: types.String(val),
|
|
adapter: adapter,
|
|
optional: opt,
|
|
}
|
|
case int:
|
|
qual = &intQualifier{
|
|
id: id, value: int64(val), celValue: types.Int(val), adapter: adapter, optional: opt,
|
|
}
|
|
case int32:
|
|
qual = &intQualifier{
|
|
id: id, value: int64(val), celValue: types.Int(val), adapter: adapter, optional: opt,
|
|
}
|
|
case int64:
|
|
qual = &intQualifier{
|
|
id: id, value: val, celValue: types.Int(val), adapter: adapter, optional: opt,
|
|
}
|
|
case uint:
|
|
qual = &uintQualifier{
|
|
id: id, value: uint64(val), celValue: types.Uint(val), adapter: adapter, optional: opt,
|
|
}
|
|
case uint32:
|
|
qual = &uintQualifier{
|
|
id: id, value: uint64(val), celValue: types.Uint(val), adapter: adapter, optional: opt,
|
|
}
|
|
case uint64:
|
|
qual = &uintQualifier{
|
|
id: id, value: val, celValue: types.Uint(val), adapter: adapter, optional: opt,
|
|
}
|
|
case bool:
|
|
qual = &boolQualifier{
|
|
id: id, value: val, celValue: types.Bool(val), adapter: adapter, optional: opt,
|
|
}
|
|
case float32:
|
|
qual = &doubleQualifier{
|
|
id: id,
|
|
value: float64(val),
|
|
celValue: types.Double(val),
|
|
adapter: adapter,
|
|
optional: opt,
|
|
}
|
|
case float64:
|
|
qual = &doubleQualifier{
|
|
id: id, value: val, celValue: types.Double(val), adapter: adapter, optional: opt,
|
|
}
|
|
case types.String:
|
|
qual = &stringQualifier{
|
|
id: id, value: string(val), celValue: val, adapter: adapter, optional: opt,
|
|
}
|
|
case types.Int:
|
|
qual = &intQualifier{
|
|
id: id, value: int64(val), celValue: val, adapter: adapter, optional: opt,
|
|
}
|
|
case types.Uint:
|
|
qual = &uintQualifier{
|
|
id: id, value: uint64(val), celValue: val, adapter: adapter, optional: opt,
|
|
}
|
|
case types.Bool:
|
|
qual = &boolQualifier{
|
|
id: id, value: bool(val), celValue: val, adapter: adapter, optional: opt,
|
|
}
|
|
case types.Double:
|
|
qual = &doubleQualifier{
|
|
id: id, value: float64(val), celValue: val, adapter: adapter, optional: opt,
|
|
}
|
|
case *types.Unknown:
|
|
qual = &unknownQualifier{id: id, value: val}
|
|
default:
|
|
if q, ok := v.(Qualifier); ok {
|
|
return q, nil
|
|
}
|
|
return nil, fmt.Errorf("invalid qualifier type: %T", v)
|
|
}
|
|
return qual, nil
|
|
}
|
|
|
|
type attrQualifier struct {
|
|
id int64
|
|
Attribute
|
|
optional bool
|
|
}
|
|
|
|
// ID implements the Qualifier interface method and returns the qualification instruction id
|
|
// rather than the attribute id.
|
|
func (q *attrQualifier) ID() int64 {
|
|
return q.id
|
|
}
|
|
|
|
// IsOptional implements the Qualifier interface method.
|
|
func (q *attrQualifier) IsOptional() bool {
|
|
return q.optional
|
|
}
|
|
|
|
type stringQualifier struct {
|
|
id int64
|
|
value string
|
|
celValue ref.Val
|
|
adapter types.Adapter
|
|
optional bool
|
|
}
|
|
|
|
// ID is an implementation of the Qualifier interface method.
|
|
func (q *stringQualifier) ID() int64 {
|
|
return q.id
|
|
}
|
|
|
|
// IsOptional implements the Qualifier interface method.
|
|
func (q *stringQualifier) IsOptional() bool {
|
|
return q.optional
|
|
}
|
|
|
|
// Qualify implements the Qualifier interface method.
|
|
func (q *stringQualifier) Qualify(vars Activation, obj any) (any, error) {
|
|
val, _, err := q.qualifyInternal(vars, obj, false, false)
|
|
return val, err
|
|
}
|
|
|
|
// QualifyIfPresent is an implementation of the Qualifier interface method.
|
|
func (q *stringQualifier) QualifyIfPresent(vars Activation, obj any, presenceOnly bool) (any, bool, error) {
|
|
return q.qualifyInternal(vars, obj, true, presenceOnly)
|
|
}
|
|
|
|
func (q *stringQualifier) qualifyInternal(vars Activation, obj any, presenceTest, presenceOnly bool) (any, bool, error) {
|
|
s := q.value
|
|
switch o := obj.(type) {
|
|
case map[string]any:
|
|
obj, isKey := o[s]
|
|
if isKey {
|
|
return obj, true, nil
|
|
}
|
|
case map[string]string:
|
|
obj, isKey := o[s]
|
|
if isKey {
|
|
return obj, true, nil
|
|
}
|
|
case map[string]int:
|
|
obj, isKey := o[s]
|
|
if isKey {
|
|
return obj, true, nil
|
|
}
|
|
case map[string]int32:
|
|
obj, isKey := o[s]
|
|
if isKey {
|
|
return obj, true, nil
|
|
}
|
|
case map[string]int64:
|
|
obj, isKey := o[s]
|
|
if isKey {
|
|
return obj, true, nil
|
|
}
|
|
case map[string]uint:
|
|
obj, isKey := o[s]
|
|
if isKey {
|
|
return obj, true, nil
|
|
}
|
|
case map[string]uint32:
|
|
obj, isKey := o[s]
|
|
if isKey {
|
|
return obj, true, nil
|
|
}
|
|
case map[string]uint64:
|
|
obj, isKey := o[s]
|
|
if isKey {
|
|
return obj, true, nil
|
|
}
|
|
case map[string]float32:
|
|
obj, isKey := o[s]
|
|
if isKey {
|
|
return obj, true, nil
|
|
}
|
|
case map[string]float64:
|
|
obj, isKey := o[s]
|
|
if isKey {
|
|
return obj, true, nil
|
|
}
|
|
case map[string]bool:
|
|
obj, isKey := o[s]
|
|
if isKey {
|
|
return obj, true, nil
|
|
}
|
|
default:
|
|
return refQualify(q.adapter, obj, q.celValue, presenceTest, presenceOnly)
|
|
}
|
|
if presenceTest {
|
|
return nil, false, nil
|
|
}
|
|
return nil, false, missingKey(q.celValue)
|
|
}
|
|
|
|
// Value implements the ConstantQualifier interface
|
|
func (q *stringQualifier) Value() ref.Val {
|
|
return q.celValue
|
|
}
|
|
|
|
type intQualifier struct {
|
|
id int64
|
|
value int64
|
|
celValue ref.Val
|
|
adapter types.Adapter
|
|
optional bool
|
|
}
|
|
|
|
// ID is an implementation of the Qualifier interface method.
|
|
func (q *intQualifier) ID() int64 {
|
|
return q.id
|
|
}
|
|
|
|
// IsOptional implements the Qualifier interface method.
|
|
func (q *intQualifier) IsOptional() bool {
|
|
return q.optional
|
|
}
|
|
|
|
// Qualify implements the Qualifier interface method.
|
|
func (q *intQualifier) Qualify(vars Activation, obj any) (any, error) {
|
|
val, _, err := q.qualifyInternal(vars, obj, false, false)
|
|
return val, err
|
|
}
|
|
|
|
// QualifyIfPresent is an implementation of the Qualifier interface method.
|
|
func (q *intQualifier) QualifyIfPresent(vars Activation, obj any, presenceOnly bool) (any, bool, error) {
|
|
return q.qualifyInternal(vars, obj, true, presenceOnly)
|
|
}
|
|
|
|
func (q *intQualifier) qualifyInternal(vars Activation, obj any, presenceTest, presenceOnly bool) (any, bool, error) {
|
|
i := q.value
|
|
var isMap bool
|
|
switch o := obj.(type) {
|
|
// The specialized map types supported by an int qualifier are considerably fewer than the set
|
|
// of specialized map types supported by string qualifiers since they are less frequently used
|
|
// than string-based map keys. Additional specializations may be added in the future if
|
|
// desired.
|
|
case map[int]any:
|
|
isMap = true
|
|
obj, isKey := o[int(i)]
|
|
if isKey {
|
|
return obj, true, nil
|
|
}
|
|
case map[int32]any:
|
|
isMap = true
|
|
obj, isKey := o[int32(i)]
|
|
if isKey {
|
|
return obj, true, nil
|
|
}
|
|
case map[int64]any:
|
|
isMap = true
|
|
obj, isKey := o[i]
|
|
if isKey {
|
|
return obj, true, nil
|
|
}
|
|
case []any:
|
|
isIndex := i >= 0 && i < int64(len(o))
|
|
if isIndex {
|
|
return o[i], true, nil
|
|
}
|
|
case []string:
|
|
isIndex := i >= 0 && i < int64(len(o))
|
|
if isIndex {
|
|
return o[i], true, nil
|
|
}
|
|
case []int:
|
|
isIndex := i >= 0 && i < int64(len(o))
|
|
if isIndex {
|
|
return o[i], true, nil
|
|
}
|
|
case []int32:
|
|
isIndex := i >= 0 && i < int64(len(o))
|
|
if isIndex {
|
|
return o[i], true, nil
|
|
}
|
|
case []int64:
|
|
isIndex := i >= 0 && i < int64(len(o))
|
|
if isIndex {
|
|
return o[i], true, nil
|
|
}
|
|
case []uint:
|
|
isIndex := i >= 0 && i < int64(len(o))
|
|
if isIndex {
|
|
return o[i], true, nil
|
|
}
|
|
case []uint32:
|
|
isIndex := i >= 0 && i < int64(len(o))
|
|
if isIndex {
|
|
return o[i], true, nil
|
|
}
|
|
case []uint64:
|
|
isIndex := i >= 0 && i < int64(len(o))
|
|
if isIndex {
|
|
return o[i], true, nil
|
|
}
|
|
case []float32:
|
|
isIndex := i >= 0 && i < int64(len(o))
|
|
if isIndex {
|
|
return o[i], true, nil
|
|
}
|
|
case []float64:
|
|
isIndex := i >= 0 && i < int64(len(o))
|
|
if isIndex {
|
|
return o[i], true, nil
|
|
}
|
|
case []bool:
|
|
isIndex := i >= 0 && i < int64(len(o))
|
|
if isIndex {
|
|
return o[i], true, nil
|
|
}
|
|
default:
|
|
return refQualify(q.adapter, obj, q.celValue, presenceTest, presenceOnly)
|
|
}
|
|
if presenceTest {
|
|
return nil, false, nil
|
|
}
|
|
if isMap {
|
|
return nil, false, missingKey(q.celValue)
|
|
}
|
|
return nil, false, missingIndex(q.celValue)
|
|
}
|
|
|
|
// Value implements the ConstantQualifier interface
|
|
func (q *intQualifier) Value() ref.Val {
|
|
return q.celValue
|
|
}
|
|
|
|
type uintQualifier struct {
|
|
id int64
|
|
value uint64
|
|
celValue ref.Val
|
|
adapter types.Adapter
|
|
optional bool
|
|
}
|
|
|
|
// ID is an implementation of the Qualifier interface method.
|
|
func (q *uintQualifier) ID() int64 {
|
|
return q.id
|
|
}
|
|
|
|
// IsOptional implements the Qualifier interface method.
|
|
func (q *uintQualifier) IsOptional() bool {
|
|
return q.optional
|
|
}
|
|
|
|
// Qualify implements the Qualifier interface method.
|
|
func (q *uintQualifier) Qualify(vars Activation, obj any) (any, error) {
|
|
val, _, err := q.qualifyInternal(vars, obj, false, false)
|
|
return val, err
|
|
}
|
|
|
|
// QualifyIfPresent is an implementation of the Qualifier interface method.
|
|
func (q *uintQualifier) QualifyIfPresent(vars Activation, obj any, presenceOnly bool) (any, bool, error) {
|
|
return q.qualifyInternal(vars, obj, true, presenceOnly)
|
|
}
|
|
|
|
func (q *uintQualifier) qualifyInternal(vars Activation, obj any, presenceTest, presenceOnly bool) (any, bool, error) {
|
|
u := q.value
|
|
switch o := obj.(type) {
|
|
// The specialized map types supported by a uint qualifier are considerably fewer than the set
|
|
// of specialized map types supported by string qualifiers since they are less frequently used
|
|
// than string-based map keys. Additional specializations may be added in the future if
|
|
// desired.
|
|
case map[uint]any:
|
|
obj, isKey := o[uint(u)]
|
|
if isKey {
|
|
return obj, true, nil
|
|
}
|
|
case map[uint32]any:
|
|
obj, isKey := o[uint32(u)]
|
|
if isKey {
|
|
return obj, true, nil
|
|
}
|
|
case map[uint64]any:
|
|
obj, isKey := o[u]
|
|
if isKey {
|
|
return obj, true, nil
|
|
}
|
|
default:
|
|
return refQualify(q.adapter, obj, q.celValue, presenceTest, presenceOnly)
|
|
}
|
|
if presenceTest {
|
|
return nil, false, nil
|
|
}
|
|
return nil, false, missingKey(q.celValue)
|
|
}
|
|
|
|
// Value implements the ConstantQualifier interface
|
|
func (q *uintQualifier) Value() ref.Val {
|
|
return q.celValue
|
|
}
|
|
|
|
type boolQualifier struct {
|
|
id int64
|
|
value bool
|
|
celValue ref.Val
|
|
adapter types.Adapter
|
|
optional bool
|
|
}
|
|
|
|
// ID is an implementation of the Qualifier interface method.
|
|
func (q *boolQualifier) ID() int64 {
|
|
return q.id
|
|
}
|
|
|
|
// IsOptional implements the Qualifier interface method.
|
|
func (q *boolQualifier) IsOptional() bool {
|
|
return q.optional
|
|
}
|
|
|
|
// Qualify implements the Qualifier interface method.
|
|
func (q *boolQualifier) Qualify(vars Activation, obj any) (any, error) {
|
|
val, _, err := q.qualifyInternal(vars, obj, false, false)
|
|
return val, err
|
|
}
|
|
|
|
// QualifyIfPresent is an implementation of the Qualifier interface method.
|
|
func (q *boolQualifier) QualifyIfPresent(vars Activation, obj any, presenceOnly bool) (any, bool, error) {
|
|
return q.qualifyInternal(vars, obj, true, presenceOnly)
|
|
}
|
|
|
|
func (q *boolQualifier) qualifyInternal(vars Activation, obj any, presenceTest, presenceOnly bool) (any, bool, error) {
|
|
b := q.value
|
|
switch o := obj.(type) {
|
|
case map[bool]any:
|
|
obj, isKey := o[b]
|
|
if isKey {
|
|
return obj, true, nil
|
|
}
|
|
default:
|
|
return refQualify(q.adapter, obj, q.celValue, presenceTest, presenceOnly)
|
|
}
|
|
if presenceTest {
|
|
return nil, false, nil
|
|
}
|
|
return nil, false, missingKey(q.celValue)
|
|
}
|
|
|
|
// Value implements the ConstantQualifier interface
|
|
func (q *boolQualifier) Value() ref.Val {
|
|
return q.celValue
|
|
}
|
|
|
|
// fieldQualifier indicates that the qualification is a well-defined field with a known
|
|
// field type. When the field type is known this can be used to improve the speed and
|
|
// efficiency of field resolution.
|
|
type fieldQualifier struct {
|
|
id int64
|
|
Name string
|
|
FieldType *types.FieldType
|
|
adapter types.Adapter
|
|
optional bool
|
|
}
|
|
|
|
// ID is an implementation of the Qualifier interface method.
|
|
func (q *fieldQualifier) ID() int64 {
|
|
return q.id
|
|
}
|
|
|
|
// IsOptional implements the Qualifier interface method.
|
|
func (q *fieldQualifier) IsOptional() bool {
|
|
return q.optional
|
|
}
|
|
|
|
// Qualify implements the Qualifier interface method.
|
|
func (q *fieldQualifier) Qualify(vars Activation, obj any) (any, error) {
|
|
if rv, ok := obj.(ref.Val); ok {
|
|
obj = rv.Value()
|
|
}
|
|
val, err := q.FieldType.GetFrom(obj)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return val, nil
|
|
}
|
|
|
|
// QualifyIfPresent is an implementation of the Qualifier interface method.
|
|
func (q *fieldQualifier) QualifyIfPresent(vars Activation, obj any, presenceOnly bool) (any, bool, error) {
|
|
if rv, ok := obj.(ref.Val); ok {
|
|
obj = rv.Value()
|
|
}
|
|
if !q.FieldType.IsSet(obj) {
|
|
return nil, false, nil
|
|
}
|
|
if presenceOnly {
|
|
return nil, true, nil
|
|
}
|
|
val, err := q.FieldType.GetFrom(obj)
|
|
if err != nil {
|
|
return nil, false, err
|
|
}
|
|
return val, true, nil
|
|
}
|
|
|
|
// Value implements the ConstantQualifier interface
|
|
func (q *fieldQualifier) Value() ref.Val {
|
|
return types.String(q.Name)
|
|
}
|
|
|
|
// doubleQualifier qualifies a CEL object, map, or list using a double value.
|
|
//
|
|
// This qualifier is used for working with dynamic data like JSON or protobuf.Any where the value
|
|
// type may not be known ahead of time and may not conform to the standard types supported as valid
|
|
// protobuf map key types.
|
|
type doubleQualifier struct {
|
|
id int64
|
|
value float64
|
|
celValue ref.Val
|
|
adapter types.Adapter
|
|
optional bool
|
|
}
|
|
|
|
// ID is an implementation of the Qualifier interface method.
|
|
func (q *doubleQualifier) ID() int64 {
|
|
return q.id
|
|
}
|
|
|
|
// IsOptional implements the Qualifier interface method.
|
|
func (q *doubleQualifier) IsOptional() bool {
|
|
return q.optional
|
|
}
|
|
|
|
// Qualify implements the Qualifier interface method.
|
|
func (q *doubleQualifier) Qualify(vars Activation, obj any) (any, error) {
|
|
val, _, err := q.qualifyInternal(vars, obj, false, false)
|
|
return val, err
|
|
}
|
|
|
|
func (q *doubleQualifier) QualifyIfPresent(vars Activation, obj any, presenceOnly bool) (any, bool, error) {
|
|
return q.qualifyInternal(vars, obj, true, presenceOnly)
|
|
}
|
|
|
|
func (q *doubleQualifier) qualifyInternal(vars Activation, obj any, presenceTest, presenceOnly bool) (any, bool, error) {
|
|
return refQualify(q.adapter, obj, q.celValue, presenceTest, presenceOnly)
|
|
}
|
|
|
|
// Value implements the ConstantQualifier interface
|
|
func (q *doubleQualifier) Value() ref.Val {
|
|
return q.celValue
|
|
}
|
|
|
|
// unknownQualifier is a simple qualifier which always returns a preconfigured set of unknown values
|
|
// for any value subject to qualification. This is consistent with CEL's unknown handling elsewhere.
|
|
type unknownQualifier struct {
|
|
id int64
|
|
value *types.Unknown
|
|
}
|
|
|
|
// ID is an implementation of the Qualifier interface method.
|
|
func (q *unknownQualifier) ID() int64 {
|
|
return q.id
|
|
}
|
|
|
|
// IsOptional returns trivially false as an the unknown value is always returned.
|
|
func (q *unknownQualifier) IsOptional() bool {
|
|
return false
|
|
}
|
|
|
|
// Qualify returns the unknown value associated with this qualifier.
|
|
func (q *unknownQualifier) Qualify(vars Activation, obj any) (any, error) {
|
|
return q.value, nil
|
|
}
|
|
|
|
// QualifyIfPresent is an implementation of the Qualifier interface method.
|
|
func (q *unknownQualifier) QualifyIfPresent(vars Activation, obj any, presenceOnly bool) (any, bool, error) {
|
|
return q.value, true, nil
|
|
}
|
|
|
|
// Value implements the ConstantQualifier interface
|
|
func (q *unknownQualifier) Value() ref.Val {
|
|
return q.value
|
|
}
|
|
|
|
func applyQualifiers(vars Activation, obj any, qualifiers []Qualifier) (any, bool, error) {
|
|
optObj, isOpt := obj.(*types.Optional)
|
|
if isOpt {
|
|
if !optObj.HasValue() {
|
|
return optObj, false, nil
|
|
}
|
|
obj = optObj.GetValue().Value()
|
|
}
|
|
|
|
var err error
|
|
for _, qual := range qualifiers {
|
|
var qualObj any
|
|
isOpt = isOpt || qual.IsOptional()
|
|
if isOpt {
|
|
var present bool
|
|
qualObj, present, err = qual.QualifyIfPresent(vars, obj, false)
|
|
if err != nil {
|
|
return nil, false, err
|
|
}
|
|
if !present {
|
|
// We return optional none here with a presence of 'false' as the layers
|
|
// above will attempt to call types.OptionalOf() on a present value if any
|
|
// of the qualifiers is optional.
|
|
return types.OptionalNone, false, nil
|
|
}
|
|
} else {
|
|
qualObj, err = qual.Qualify(vars, obj)
|
|
if err != nil {
|
|
return nil, false, err
|
|
}
|
|
}
|
|
obj = qualObj
|
|
}
|
|
return obj, isOpt, nil
|
|
}
|
|
|
|
// attrQualify performs a qualification using the result of an attribute evaluation.
|
|
func attrQualify(fac AttributeFactory, vars Activation, obj any, qualAttr Attribute) (any, error) {
|
|
val, err := qualAttr.Resolve(vars)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
qual, err := fac.NewQualifier(nil, qualAttr.ID(), val, qualAttr.IsOptional())
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return qual.Qualify(vars, obj)
|
|
}
|
|
|
|
// attrQualifyIfPresent conditionally performs the qualification of the result of attribute is present
|
|
// on the target object.
|
|
func attrQualifyIfPresent(fac AttributeFactory, vars Activation, obj any, qualAttr Attribute,
|
|
presenceOnly bool) (any, bool, error) {
|
|
val, err := qualAttr.Resolve(vars)
|
|
if err != nil {
|
|
return nil, false, err
|
|
}
|
|
qual, err := fac.NewQualifier(nil, qualAttr.ID(), val, qualAttr.IsOptional())
|
|
if err != nil {
|
|
return nil, false, err
|
|
}
|
|
return qual.QualifyIfPresent(vars, obj, presenceOnly)
|
|
}
|
|
|
|
// refQualify attempts to convert the value to a CEL value and then uses reflection methods to try and
|
|
// apply the qualifier with the option to presence test field accesses before retrieving field values.
|
|
func refQualify(adapter types.Adapter, obj any, idx ref.Val, presenceTest, presenceOnly bool) (ref.Val, bool, error) {
|
|
celVal := adapter.NativeToValue(obj)
|
|
switch v := celVal.(type) {
|
|
case *types.Unknown:
|
|
return v, true, nil
|
|
case *types.Err:
|
|
return nil, false, v
|
|
case traits.Mapper:
|
|
val, found := v.Find(idx)
|
|
// If the index is of the wrong type for the map, then it is possible
|
|
// for the Find call to produce an error.
|
|
if types.IsError(val) {
|
|
return nil, false, val.(*types.Err)
|
|
}
|
|
if found {
|
|
return val, true, nil
|
|
}
|
|
if presenceTest {
|
|
return nil, false, nil
|
|
}
|
|
return nil, false, missingKey(idx)
|
|
case traits.Lister:
|
|
// If the index argument is not a valid numeric type, then it is possible
|
|
// for the index operation to produce an error.
|
|
i, err := types.IndexOrError(idx)
|
|
if err != nil {
|
|
return nil, false, err
|
|
}
|
|
celIndex := types.Int(i)
|
|
if i >= 0 && celIndex < v.Size().(types.Int) {
|
|
return v.Get(idx), true, nil
|
|
}
|
|
if presenceTest {
|
|
return nil, false, nil
|
|
}
|
|
return nil, false, missingIndex(idx)
|
|
case traits.Indexer:
|
|
if presenceTest {
|
|
ft, ok := v.(traits.FieldTester)
|
|
if ok {
|
|
presence := ft.IsSet(idx)
|
|
if types.IsError(presence) {
|
|
return nil, false, presence.(*types.Err)
|
|
}
|
|
// If not found or presence only test, then return.
|
|
// Otherwise, if found, obtain the value later on.
|
|
if presenceOnly || presence == types.False {
|
|
return nil, presence == types.True, nil
|
|
}
|
|
}
|
|
}
|
|
val := v.Get(idx)
|
|
if types.IsError(val) {
|
|
return nil, false, val.(*types.Err)
|
|
}
|
|
return val, true, nil
|
|
default:
|
|
if presenceTest {
|
|
return nil, false, nil
|
|
}
|
|
return nil, false, missingKey(idx)
|
|
}
|
|
}
|
|
|
|
// resolutionError is a custom error type which encodes the different error states which may
|
|
// occur during attribute resolution.
|
|
type resolutionError struct {
|
|
missingAttribute string
|
|
missingIndex ref.Val
|
|
missingKey ref.Val
|
|
}
|
|
|
|
func (e *resolutionError) isMissingAttribute() bool {
|
|
return e.missingAttribute != ""
|
|
}
|
|
|
|
func missingIndex(missing ref.Val) *resolutionError {
|
|
return &resolutionError{
|
|
missingIndex: missing,
|
|
}
|
|
}
|
|
|
|
func missingKey(missing ref.Val) *resolutionError {
|
|
return &resolutionError{
|
|
missingKey: missing,
|
|
}
|
|
}
|
|
|
|
func missingAttribute(attr string) *resolutionError {
|
|
return &resolutionError{
|
|
missingAttribute: attr,
|
|
}
|
|
}
|
|
|
|
// Error implements the error interface method.
|
|
func (e *resolutionError) Error() string {
|
|
if e.missingKey != nil {
|
|
return fmt.Sprintf("no such key: %v", e.missingKey)
|
|
}
|
|
if e.missingIndex != nil {
|
|
return fmt.Sprintf("index out of bounds: %v", e.missingIndex)
|
|
}
|
|
if e.missingAttribute != "" {
|
|
return fmt.Sprintf("no such attribute(s): %s", e.missingAttribute)
|
|
}
|
|
return "invalid attribute"
|
|
}
|
|
|
|
// Is implements the errors.Is() method used by more recent versions of Go.
|
|
func (e *resolutionError) Is(err error) bool {
|
|
return err.Error() == e.Error()
|
|
}
|