local-server/vendor/gopkg.in/src-d/go-git.v4/plumbing/protocol/packp/ulreq.go
2019-02-28 19:27:09 +11:00

169 lines
4.8 KiB
Go

package packp
import (
"fmt"
"time"
"gopkg.in/src-d/go-git.v4/plumbing"
"gopkg.in/src-d/go-git.v4/plumbing/protocol/packp/capability"
)
// UploadRequest values represent the information transmitted on a
// upload-request message. Values from this type are not zero-value
// safe, use the New function instead.
// This is a low level type, use UploadPackRequest instead.
type UploadRequest struct {
Capabilities *capability.List
Wants []plumbing.Hash
Shallows []plumbing.Hash
Depth Depth
}
// Depth values stores the desired depth of the requested packfile: see
// DepthCommit, DepthSince and DepthReference.
type Depth interface {
isDepth()
IsZero() bool
}
// DepthCommits values stores the maximum number of requested commits in
// the packfile. Zero means infinite. A negative value will have
// undefined consequences.
type DepthCommits int
func (d DepthCommits) isDepth() {}
func (d DepthCommits) IsZero() bool {
return d == 0
}
// DepthSince values requests only commits newer than the specified time.
type DepthSince time.Time
func (d DepthSince) isDepth() {}
func (d DepthSince) IsZero() bool {
return time.Time(d).IsZero()
}
// DepthReference requests only commits not to found in the specified reference.
type DepthReference string
func (d DepthReference) isDepth() {}
func (d DepthReference) IsZero() bool {
return string(d) == ""
}
// NewUploadRequest returns a pointer to a new UploadRequest value, ready to be
// used. It has no capabilities, wants or shallows and an infinite depth. Please
// note that to encode an upload-request it has to have at least one wanted hash.
func NewUploadRequest() *UploadRequest {
return &UploadRequest{
Capabilities: capability.NewList(),
Wants: []plumbing.Hash{},
Shallows: []plumbing.Hash{},
Depth: DepthCommits(0),
}
}
// NewUploadRequestFromCapabilities returns a pointer to a new UploadRequest
// value, the request capabilities are filled with the most optiomal ones, based
// on the adv value (advertaised capabilities), the UploadRequest generated it
// has no wants or shallows and an infinite depth.
func NewUploadRequestFromCapabilities(adv *capability.List) *UploadRequest {
r := NewUploadRequest()
if adv.Supports(capability.MultiACKDetailed) {
r.Capabilities.Set(capability.MultiACKDetailed)
} else if adv.Supports(capability.MultiACK) {
r.Capabilities.Set(capability.MultiACK)
}
if adv.Supports(capability.Sideband64k) {
r.Capabilities.Set(capability.Sideband64k)
} else if adv.Supports(capability.Sideband) {
r.Capabilities.Set(capability.Sideband)
}
if adv.Supports(capability.ThinPack) {
r.Capabilities.Set(capability.ThinPack)
}
if adv.Supports(capability.OFSDelta) {
r.Capabilities.Set(capability.OFSDelta)
}
if adv.Supports(capability.Agent) {
r.Capabilities.Set(capability.Agent, capability.DefaultAgent)
}
return r
}
// Validate validates the content of UploadRequest, following the next rules:
// - Wants MUST have at least one reference
// - capability.Shallow MUST be present if Shallows is not empty
// - is a non-zero DepthCommits is given capability.Shallow MUST be present
// - is a DepthSince is given capability.Shallow MUST be present
// - is a DepthReference is given capability.DeepenNot MUST be present
// - MUST contain only maximum of one of capability.Sideband and capability.Sideband64k
// - MUST contain only maximum of one of capability.MultiACK and capability.MultiACKDetailed
func (r *UploadRequest) Validate() error {
if len(r.Wants) == 0 {
return fmt.Errorf("want can't be empty")
}
if err := r.validateRequiredCapabilities(); err != nil {
return err
}
if err := r.validateConflictCapabilities(); err != nil {
return err
}
return nil
}
func (r *UploadRequest) validateRequiredCapabilities() error {
msg := "missing capability %s"
if len(r.Shallows) != 0 && !r.Capabilities.Supports(capability.Shallow) {
return fmt.Errorf(msg, capability.Shallow)
}
switch r.Depth.(type) {
case DepthCommits:
if r.Depth != DepthCommits(0) {
if !r.Capabilities.Supports(capability.Shallow) {
return fmt.Errorf(msg, capability.Shallow)
}
}
case DepthSince:
if !r.Capabilities.Supports(capability.DeepenSince) {
return fmt.Errorf(msg, capability.DeepenSince)
}
case DepthReference:
if !r.Capabilities.Supports(capability.DeepenNot) {
return fmt.Errorf(msg, capability.DeepenNot)
}
}
return nil
}
func (r *UploadRequest) validateConflictCapabilities() error {
msg := "capabilities %s and %s are mutually exclusive"
if r.Capabilities.Supports(capability.Sideband) &&
r.Capabilities.Supports(capability.Sideband64k) {
return fmt.Errorf(msg, capability.Sideband, capability.Sideband64k)
}
if r.Capabilities.Supports(capability.MultiACK) &&
r.Capabilities.Supports(capability.MultiACKDetailed) {
return fmt.Errorf(msg, capability.MultiACK, capability.MultiACKDetailed)
}
return nil
}