mirror of
https://github.com/rocky-linux/peridot.git
synced 2024-11-30 16:46:27 +00:00
442 lines
19 KiB
Markdown
442 lines
19 KiB
Markdown
# <img alt="chi" src="https://cdn.rawgit.com/go-chi/chi/master/_examples/chi.svg" width="220" />
|
|
|
|
|
|
[![GoDoc Widget]][GoDoc] [![Travis Widget]][Travis]
|
|
|
|
`chi` is a lightweight, idiomatic and composable router for building Go HTTP services. It's
|
|
especially good at helping you write large REST API services that are kept maintainable as your
|
|
project grows and changes. `chi` is built on the new `context` package introduced in Go 1.7 to
|
|
handle signaling, cancelation and request-scoped values across a handler chain.
|
|
|
|
The focus of the project has been to seek out an elegant and comfortable design for writing
|
|
REST API servers, written during the development of the Pressly API service that powers our
|
|
public API service, which in turn powers all of our client-side applications.
|
|
|
|
The key considerations of chi's design are: project structure, maintainability, standard http
|
|
handlers (stdlib-only), developer productivity, and deconstructing a large system into many small
|
|
parts. The core router `github.com/go-chi/chi` is quite small (less than 1000 LOC), but we've also
|
|
included some useful/optional subpackages: [middleware](/middleware), [render](https://github.com/go-chi/render) and [docgen](https://github.com/go-chi/docgen). We hope you enjoy it too!
|
|
|
|
## Install
|
|
|
|
`go get -u github.com/go-chi/chi`
|
|
|
|
|
|
## Features
|
|
|
|
* **Lightweight** - cloc'd in ~1000 LOC for the chi router
|
|
* **Fast** - yes, see [benchmarks](#benchmarks)
|
|
* **100% compatible with net/http** - use any http or middleware pkg in the ecosystem that is also compatible with `net/http`
|
|
* **Designed for modular/composable APIs** - middlewares, inline middlewares, route groups and subrouter mounting
|
|
* **Context control** - built on new `context` package, providing value chaining, cancellations and timeouts
|
|
* **Robust** - in production at Pressly, CloudFlare, Heroku, 99Designs, and many others (see [discussion](https://github.com/go-chi/chi/issues/91))
|
|
* **Doc generation** - `docgen` auto-generates routing documentation from your source to JSON or Markdown
|
|
* **No external dependencies** - plain ol' Go stdlib + net/http
|
|
|
|
|
|
## Examples
|
|
|
|
See [_examples/](https://github.com/go-chi/chi/blob/master/_examples/) for a variety of examples.
|
|
|
|
|
|
**As easy as:**
|
|
|
|
```go
|
|
package main
|
|
|
|
import (
|
|
"net/http"
|
|
|
|
"github.com/go-chi/chi"
|
|
"github.com/go-chi/chi/middleware"
|
|
)
|
|
|
|
func main() {
|
|
r := chi.NewRouter()
|
|
r.Use(middleware.Logger)
|
|
r.Get("/", func(w http.ResponseWriter, r *http.Request) {
|
|
w.Write([]byte("welcome"))
|
|
})
|
|
http.ListenAndServe(":3000", r)
|
|
}
|
|
```
|
|
|
|
**REST Preview:**
|
|
|
|
Here is a little preview of how routing looks like with chi. Also take a look at the generated routing docs
|
|
in JSON ([routes.json](https://github.com/go-chi/chi/blob/master/_examples/rest/routes.json)) and in
|
|
Markdown ([routes.md](https://github.com/go-chi/chi/blob/master/_examples/rest/routes.md)).
|
|
|
|
I highly recommend reading the source of the [examples](https://github.com/go-chi/chi/blob/master/_examples/) listed
|
|
above, they will show you all the features of chi and serve as a good form of documentation.
|
|
|
|
```go
|
|
import (
|
|
//...
|
|
"context"
|
|
"github.com/go-chi/chi"
|
|
"github.com/go-chi/chi/middleware"
|
|
)
|
|
|
|
func main() {
|
|
r := chi.NewRouter()
|
|
|
|
// A good base middleware stack
|
|
r.Use(middleware.RequestID)
|
|
r.Use(middleware.RealIP)
|
|
r.Use(middleware.Logger)
|
|
r.Use(middleware.Recoverer)
|
|
|
|
// Set a timeout value on the request context (ctx), that will signal
|
|
// through ctx.Done() that the request has timed out and further
|
|
// processing should be stopped.
|
|
r.Use(middleware.Timeout(60 * time.Second))
|
|
|
|
r.Get("/", func(w http.ResponseWriter, r *http.Request) {
|
|
w.Write([]byte("hi"))
|
|
})
|
|
|
|
// RESTy routes for "articles" resource
|
|
r.Route("/articles", func(r chi.Router) {
|
|
r.With(paginate).Get("/", listArticles) // GET /articles
|
|
r.With(paginate).Get("/{month}-{day}-{year}", listArticlesByDate) // GET /articles/01-16-2017
|
|
|
|
r.Post("/", createArticle) // POST /articles
|
|
r.Get("/search", searchArticles) // GET /articles/search
|
|
|
|
// Regexp url parameters:
|
|
r.Get("/{articleSlug:[a-z-]+}", getArticleBySlug) // GET /articles/home-is-toronto
|
|
|
|
// Subrouters:
|
|
r.Route("/{articleID}", func(r chi.Router) {
|
|
r.Use(ArticleCtx)
|
|
r.Get("/", getArticle) // GET /articles/123
|
|
r.Put("/", updateArticle) // PUT /articles/123
|
|
r.Delete("/", deleteArticle) // DELETE /articles/123
|
|
})
|
|
})
|
|
|
|
// Mount the admin sub-router
|
|
r.Mount("/admin", adminRouter())
|
|
|
|
http.ListenAndServe(":3333", r)
|
|
}
|
|
|
|
func ArticleCtx(next http.Handler) http.Handler {
|
|
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
|
|
articleID := chi.URLParam(r, "articleID")
|
|
article, err := dbGetArticle(articleID)
|
|
if err != nil {
|
|
http.Error(w, http.StatusText(404), 404)
|
|
return
|
|
}
|
|
ctx := context.WithValue(r.Context(), "article", article)
|
|
next.ServeHTTP(w, r.WithContext(ctx))
|
|
})
|
|
}
|
|
|
|
func getArticle(w http.ResponseWriter, r *http.Request) {
|
|
ctx := r.Context()
|
|
article, ok := ctx.Value("article").(*Article)
|
|
if !ok {
|
|
http.Error(w, http.StatusText(422), 422)
|
|
return
|
|
}
|
|
w.Write([]byte(fmt.Sprintf("title:%s", article.Title)))
|
|
}
|
|
|
|
// A completely separate router for administrator routes
|
|
func adminRouter() http.Handler {
|
|
r := chi.NewRouter()
|
|
r.Use(AdminOnly)
|
|
r.Get("/", adminIndex)
|
|
r.Get("/accounts", adminListAccounts)
|
|
return r
|
|
}
|
|
|
|
func AdminOnly(next http.Handler) http.Handler {
|
|
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
|
|
ctx := r.Context()
|
|
perm, ok := ctx.Value("acl.permission").(YourPermissionType)
|
|
if !ok || !perm.IsAdmin() {
|
|
http.Error(w, http.StatusText(403), 403)
|
|
return
|
|
}
|
|
next.ServeHTTP(w, r)
|
|
})
|
|
}
|
|
```
|
|
|
|
|
|
## Router design
|
|
|
|
chi's router is based on a kind of [Patricia Radix trie](https://en.wikipedia.org/wiki/Radix_tree).
|
|
The router is fully compatible with `net/http`.
|
|
|
|
Built on top of the tree is the `Router` interface:
|
|
|
|
```go
|
|
// Router consisting of the core routing methods used by chi's Mux,
|
|
// using only the standard net/http.
|
|
type Router interface {
|
|
http.Handler
|
|
Routes
|
|
|
|
// Use appends one or more middlewares onto the Router stack.
|
|
Use(middlewares ...func(http.Handler) http.Handler)
|
|
|
|
// With adds inline middlewares for an endpoint handler.
|
|
With(middlewares ...func(http.Handler) http.Handler) Router
|
|
|
|
// Group adds a new inline-Router along the current routing
|
|
// path, with a fresh middleware stack for the inline-Router.
|
|
Group(fn func(r Router)) Router
|
|
|
|
// Route mounts a sub-Router along a `pattern`` string.
|
|
Route(pattern string, fn func(r Router)) Router
|
|
|
|
// Mount attaches another http.Handler along ./pattern/*
|
|
Mount(pattern string, h http.Handler)
|
|
|
|
// Handle and HandleFunc adds routes for `pattern` that matches
|
|
// all HTTP methods.
|
|
Handle(pattern string, h http.Handler)
|
|
HandleFunc(pattern string, h http.HandlerFunc)
|
|
|
|
// Method and MethodFunc adds routes for `pattern` that matches
|
|
// the `method` HTTP method.
|
|
Method(method, pattern string, h http.Handler)
|
|
MethodFunc(method, pattern string, h http.HandlerFunc)
|
|
|
|
// HTTP-method routing along `pattern`
|
|
Connect(pattern string, h http.HandlerFunc)
|
|
Delete(pattern string, h http.HandlerFunc)
|
|
Get(pattern string, h http.HandlerFunc)
|
|
Head(pattern string, h http.HandlerFunc)
|
|
Options(pattern string, h http.HandlerFunc)
|
|
Patch(pattern string, h http.HandlerFunc)
|
|
Post(pattern string, h http.HandlerFunc)
|
|
Put(pattern string, h http.HandlerFunc)
|
|
Trace(pattern string, h http.HandlerFunc)
|
|
|
|
// NotFound defines a handler to respond whenever a route could
|
|
// not be found.
|
|
NotFound(h http.HandlerFunc)
|
|
|
|
// MethodNotAllowed defines a handler to respond whenever a method is
|
|
// not allowed.
|
|
MethodNotAllowed(h http.HandlerFunc)
|
|
}
|
|
|
|
// Routes interface adds two methods for router traversal, which is also
|
|
// used by the github.com/go-chi/docgen package to generate documentation for Routers.
|
|
type Routes interface {
|
|
// Routes returns the routing tree in an easily traversable structure.
|
|
Routes() []Route
|
|
|
|
// Middlewares returns the list of middlewares in use by the router.
|
|
Middlewares() Middlewares
|
|
|
|
// Match searches the routing tree for a handler that matches
|
|
// the method/path - similar to routing a http request, but without
|
|
// executing the handler thereafter.
|
|
Match(rctx *Context, method, path string) bool
|
|
}
|
|
```
|
|
|
|
Each routing method accepts a URL `pattern` and chain of `handlers`. The URL pattern
|
|
supports named params (ie. `/users/{userID}`) and wildcards (ie. `/admin/*`). URL parameters
|
|
can be fetched at runtime by calling `chi.URLParam(r, "userID")` for named parameters
|
|
and `chi.URLParam(r, "*")` for a wildcard parameter.
|
|
|
|
|
|
### Middleware handlers
|
|
|
|
chi's middlewares are just stdlib net/http middleware handlers. There is nothing special
|
|
about them, which means the router and all the tooling is designed to be compatible and
|
|
friendly with any middleware in the community. This offers much better extensibility and reuse
|
|
of packages and is at the heart of chi's purpose.
|
|
|
|
Here is an example of a standard net/http middleware handler using the new request context
|
|
available in Go. This middleware sets a hypothetical user identifier on the request
|
|
context and calls the next handler in the chain.
|
|
|
|
```go
|
|
// HTTP middleware setting a value on the request context
|
|
func MyMiddleware(next http.Handler) http.Handler {
|
|
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
|
|
ctx := context.WithValue(r.Context(), "user", "123")
|
|
next.ServeHTTP(w, r.WithContext(ctx))
|
|
})
|
|
}
|
|
```
|
|
|
|
|
|
### Request handlers
|
|
|
|
chi uses standard net/http request handlers. This little snippet is an example of a http.Handler
|
|
func that reads a user identifier from the request context - hypothetically, identifying
|
|
the user sending an authenticated request, validated+set by a previous middleware handler.
|
|
|
|
```go
|
|
// HTTP handler accessing data from the request context.
|
|
func MyRequestHandler(w http.ResponseWriter, r *http.Request) {
|
|
user := r.Context().Value("user").(string)
|
|
w.Write([]byte(fmt.Sprintf("hi %s", user)))
|
|
}
|
|
```
|
|
|
|
|
|
### URL parameters
|
|
|
|
chi's router parses and stores URL parameters right onto the request context. Here is
|
|
an example of how to access URL params in your net/http handlers. And of course, middlewares
|
|
are able to access the same information.
|
|
|
|
```go
|
|
// HTTP handler accessing the url routing parameters.
|
|
func MyRequestHandler(w http.ResponseWriter, r *http.Request) {
|
|
userID := chi.URLParam(r, "userID") // from a route like /users/{userID}
|
|
|
|
ctx := r.Context()
|
|
key := ctx.Value("key").(string)
|
|
|
|
w.Write([]byte(fmt.Sprintf("hi %v, %v", userID, key)))
|
|
}
|
|
```
|
|
|
|
|
|
## Middlewares
|
|
|
|
chi comes equipped with an optional `middleware` package, providing a suite of standard
|
|
`net/http` middlewares. Please note, any middleware in the ecosystem that is also compatible
|
|
with `net/http` can be used with chi's mux.
|
|
|
|
### Core middlewares
|
|
|
|
-----------------------------------------------------------------------------------------------------------
|
|
| chi/middleware Handler | description |
|
|
|:----------------------|:---------------------------------------------------------------------------------
|
|
| AllowContentType | Explicit whitelist of accepted request Content-Types |
|
|
| BasicAuth | Basic HTTP authentication |
|
|
| Compress | Gzip compression for clients that accept compressed responses |
|
|
| GetHead | Automatically route undefined HEAD requests to GET handlers |
|
|
| Heartbeat | Monitoring endpoint to check the servers pulse |
|
|
| Logger | Logs the start and end of each request with the elapsed processing time |
|
|
| NoCache | Sets response headers to prevent clients from caching |
|
|
| Profiler | Easily attach net/http/pprof to your routers |
|
|
| RealIP | Sets a http.Request's RemoteAddr to either X-Forwarded-For or X-Real-IP |
|
|
| Recoverer | Gracefully absorb panics and prints the stack trace |
|
|
| RequestID | Injects a request ID into the context of each request |
|
|
| RedirectSlashes | Redirect slashes on routing paths |
|
|
| SetHeader | Short-hand middleware to set a response header key/value |
|
|
| StripSlashes | Strip slashes on routing paths |
|
|
| Throttle | Puts a ceiling on the number of concurrent requests |
|
|
| Timeout | Signals to the request context when the timeout deadline is reached |
|
|
| URLFormat | Parse extension from url and put it on request context |
|
|
| WithValue | Short-hand middleware to set a key/value on the request context |
|
|
-----------------------------------------------------------------------------------------------------------
|
|
|
|
### Extra middlewares & packages
|
|
|
|
Please see https://github.com/go-chi for additional packages.
|
|
|
|
--------------------------------------------------------------------------------------------------------------------
|
|
| package | description |
|
|
|:---------------------------------------------------|:-------------------------------------------------------------
|
|
| [cors](https://github.com/go-chi/cors) | Cross-origin resource sharing (CORS) |
|
|
| [docgen](https://github.com/go-chi/docgen) | Print chi.Router routes at runtime |
|
|
| [jwtauth](https://github.com/go-chi/jwtauth) | JWT authentication |
|
|
| [hostrouter](https://github.com/go-chi/hostrouter) | Domain/host based request routing |
|
|
| [httplog](https://github.com/go-chi/httplog) | Small but powerful structured HTTP request logging |
|
|
| [httprate](https://github.com/go-chi/httprate) | HTTP request rate limiter |
|
|
| [httptracer](https://github.com/go-chi/httptracer) | HTTP request performance tracing library |
|
|
| [httpvcr](https://github.com/go-chi/httpvcr) | Write deterministic tests for external sources |
|
|
| [stampede](https://github.com/go-chi/stampede) | HTTP request coalescer |
|
|
--------------------------------------------------------------------------------------------------------------------
|
|
|
|
please [submit a PR](./CONTRIBUTING.md) if you'd like to include a link to a chi-compatible middleware
|
|
|
|
|
|
## context?
|
|
|
|
`context` is a tiny pkg that provides simple interface to signal context across call stacks
|
|
and goroutines. It was originally written by [Sameer Ajmani](https://github.com/Sajmani)
|
|
and is available in stdlib since go1.7.
|
|
|
|
Learn more at https://blog.golang.org/context
|
|
|
|
and..
|
|
* Docs: https://golang.org/pkg/context
|
|
* Source: https://github.com/golang/go/tree/master/src/context
|
|
|
|
|
|
## Benchmarks
|
|
|
|
The benchmark suite: https://github.com/pkieltyka/go-http-routing-benchmark
|
|
|
|
Results as of Jan 9, 2019 with Go 1.11.4 on Linux X1 Carbon laptop
|
|
|
|
```shell
|
|
BenchmarkChi_Param 3000000 475 ns/op 432 B/op 3 allocs/op
|
|
BenchmarkChi_Param5 2000000 696 ns/op 432 B/op 3 allocs/op
|
|
BenchmarkChi_Param20 1000000 1275 ns/op 432 B/op 3 allocs/op
|
|
BenchmarkChi_ParamWrite 3000000 505 ns/op 432 B/op 3 allocs/op
|
|
BenchmarkChi_GithubStatic 3000000 508 ns/op 432 B/op 3 allocs/op
|
|
BenchmarkChi_GithubParam 2000000 669 ns/op 432 B/op 3 allocs/op
|
|
BenchmarkChi_GithubAll 10000 134627 ns/op 87699 B/op 609 allocs/op
|
|
BenchmarkChi_GPlusStatic 3000000 402 ns/op 432 B/op 3 allocs/op
|
|
BenchmarkChi_GPlusParam 3000000 500 ns/op 432 B/op 3 allocs/op
|
|
BenchmarkChi_GPlus2Params 3000000 586 ns/op 432 B/op 3 allocs/op
|
|
BenchmarkChi_GPlusAll 200000 7237 ns/op 5616 B/op 39 allocs/op
|
|
BenchmarkChi_ParseStatic 3000000 408 ns/op 432 B/op 3 allocs/op
|
|
BenchmarkChi_ParseParam 3000000 488 ns/op 432 B/op 3 allocs/op
|
|
BenchmarkChi_Parse2Params 3000000 551 ns/op 432 B/op 3 allocs/op
|
|
BenchmarkChi_ParseAll 100000 13508 ns/op 11232 B/op 78 allocs/op
|
|
BenchmarkChi_StaticAll 20000 81933 ns/op 67826 B/op 471 allocs/op
|
|
```
|
|
|
|
Comparison with other routers: https://gist.github.com/pkieltyka/123032f12052520aaccab752bd3e78cc
|
|
|
|
NOTE: the allocs in the benchmark above are from the calls to http.Request's
|
|
`WithContext(context.Context)` method that clones the http.Request, sets the `Context()`
|
|
on the duplicated (alloc'd) request and returns it the new request object. This is just
|
|
how setting context on a request in Go works.
|
|
|
|
|
|
## Credits
|
|
|
|
* Carl Jackson for https://github.com/zenazn/goji
|
|
* Parts of chi's thinking comes from goji, and chi's middleware package
|
|
sources from goji.
|
|
* Armon Dadgar for https://github.com/armon/go-radix
|
|
* Contributions: [@VojtechVitek](https://github.com/VojtechVitek)
|
|
|
|
We'll be more than happy to see [your contributions](./CONTRIBUTING.md)!
|
|
|
|
|
|
## Beyond REST
|
|
|
|
chi is just a http router that lets you decompose request handling into many smaller layers.
|
|
Many companies use chi to write REST services for their public APIs. But, REST is just a convention
|
|
for managing state via HTTP, and there's a lot of other pieces required to write a complete client-server
|
|
system or network of microservices.
|
|
|
|
Looking beyond REST, I also recommend some newer works in the field:
|
|
* [webrpc](https://github.com/webrpc/webrpc) - Web-focused RPC client+server framework with code-gen
|
|
* [gRPC](https://github.com/grpc/grpc-go) - Google's RPC framework via protobufs
|
|
* [graphql](https://github.com/99designs/gqlgen) - Declarative query language
|
|
* [NATS](https://nats.io) - lightweight pub-sub
|
|
|
|
|
|
## License
|
|
|
|
Copyright (c) 2015-present [Peter Kieltyka](https://github.com/pkieltyka)
|
|
|
|
Licensed under [MIT License](./LICENSE)
|
|
|
|
[GoDoc]: https://godoc.org/github.com/go-chi/chi
|
|
[GoDoc Widget]: https://godoc.org/github.com/go-chi/chi?status.svg
|
|
[Travis]: https://travis-ci.org/go-chi/chi
|
|
[Travis Widget]: https://travis-ci.org/go-chi/chi.svg?branch=master
|