mirror of
https://github.com/ceph/ceph-csi.git
synced 2024-11-10 08:20:23 +00:00
89 lines
3.4 KiB
Markdown
89 lines
3.4 KiB
Markdown
|
merry [](https://github.com/ansel1/merry/actions?query=branch%3Amaster+workflow%3ABuild+) [](https://godoc.org/github.com/ansel1/merry/v2) [](https://goreportcard.com/report/github.com/ansel1/merry/v2)
|
||
|
|
=====
|
||
|
|
|
||
|
|
Add context to errors, including automatic stack capture, cause chains, HTTP status code, user
|
||
|
|
messages, and arbitrary values.
|
||
|
|
|
||
|
|
The package is largely based on http://github.com/go-errors/errors, with additional
|
||
|
|
inspiration from https://github.com/go-errgo/errgo and https://github.com/amattn/deeperror.
|
||
|
|
|
||
|
|
Installation
|
||
|
|
------------
|
||
|
|
|
||
|
|
go get github.com/ansel1/merry/v2
|
||
|
|
|
||
|
|
Features
|
||
|
|
--------
|
||
|
|
|
||
|
|
Wrapped errors work a lot like google's golang.org/x/net/context package:
|
||
|
|
each wrapper error contains the inner error, a key, and a value.
|
||
|
|
Like contexts, errors are immutable: adding a key/value to an error
|
||
|
|
always creates a new error which wraps the original.
|
||
|
|
|
||
|
|
This package comes with built-in support for adding information to errors:
|
||
|
|
|
||
|
|
* stacktraces
|
||
|
|
* changing the error message
|
||
|
|
* HTTP status codes
|
||
|
|
* End user error messages
|
||
|
|
* causes
|
||
|
|
|
||
|
|
You can also add your own additional information.
|
||
|
|
|
||
|
|
The stack capturing feature can be turned off for better performance, though it's pretty fast. Benchmarks
|
||
|
|
on an 2017 MacBook Pro, with go 1.10:
|
||
|
|
|
||
|
|
BenchmarkNew_withStackCapture-8 2000000 749 ns/op
|
||
|
|
BenchmarkNew_withoutStackCapture-8 20000000 64.1 ns/op
|
||
|
|
|
||
|
|
Merry errors are fully compatible with errors.Is, As, and Unwrap.
|
||
|
|
|
||
|
|
Example
|
||
|
|
-------
|
||
|
|
|
||
|
|
To add a stacktrace, a user message, and an HTTP code to an error:
|
||
|
|
|
||
|
|
err = merry.Wrap(err, WithUserMessagef("Username %s not found.", username), WithHTTPCode(404))
|
||
|
|
|
||
|
|
To fetch context information from error:
|
||
|
|
|
||
|
|
userMsg := UserMessage(err)
|
||
|
|
statusCode := HTTPCode(err)
|
||
|
|
stacktrace := Stacktrace(err)
|
||
|
|
|
||
|
|
To print full details of the error:
|
||
|
|
|
||
|
|
log.Printf("%v+", err) // or log.Println(merry.Details(err))
|
||
|
|
|
||
|
|
v1 -> v2
|
||
|
|
--------
|
||
|
|
|
||
|
|
v1 used a fluent API style which proved awkward in some cases. In general, fluent APIs
|
||
|
|
don't work that well in go, because they interfere with how interfaces are typically used to
|
||
|
|
compose with other packages. v2 uses a functional options API style which more easily
|
||
|
|
allows other packages to augment this one.
|
||
|
|
|
||
|
|
This also fixed bad smell with v1's APIs: they mostly returned a big, ugly `merry.Error` interface,
|
||
|
|
instead of plain `error` instances. v2 has a smaller, simpler API, which exclusively uses plain
|
||
|
|
errors.
|
||
|
|
|
||
|
|
v2 also implements a simpler and more robust integration with errors.Is/As/Unwrap. v2's functions will
|
||
|
|
work with error wrapper chains even if those chains contain errors not created with this package, so
|
||
|
|
long as those errors conform to the Unwrap() convention.
|
||
|
|
|
||
|
|
v2 allows more granular control over stacktraces: stack capture can be turned on or off on individual errors,
|
||
|
|
overriding the global setting. External stacktraces can be used as well.
|
||
|
|
|
||
|
|
v1 has been reimplemented in terms of v2, and the versions are completely compatible, and can be mixed.
|
||
|
|
|
||
|
|
Plugs
|
||
|
|
-----
|
||
|
|
|
||
|
|
- Check out my HTTP client library: [github.com/gemalto/requester](https://github.com/gemalto/requester)
|
||
|
|
- Check out my log library: [github.com/gemalto/flume](https://github.com/gemalto/flume)
|
||
|
|
|
||
|
|
License
|
||
|
|
-------
|
||
|
|
|
||
|
|
This package is licensed under the MIT license, see LICENSE.MIT for details.
|