fasthttp-routing is a Go package that is adapted from ozzo-routing to provide fast and powerful routing features for the high-performance fasthttp server. The package has the following features:
- middleware pipeline architecture, similar to that of the Express framework.
- extremely fast request routing with zero dynamic memory allocation
- modular code organization through route grouping
- flexible URL path matching, supporting URL parameters and regular expressions
- URL creation according to the predefined routes
- ready-to-use handlers sufficient for building RESTful APIs
Go 1.7 or above.
Run the following command to install the package:
go get github.com/jackwhelpton/fasthttp-routing
You may also get specified release of the package by:
go get gopkg.in/jackwhelpton/fasthttp-routing.v1
Create a server.go file with the following content:
package main
import (
"log"
"github.com/jackwhelpton/fasthttp-routing"
"github.com/jackwhelpton/fasthttp-routing/access"
"github.com/jackwhelpton/fasthttp-routing/slash"
"github.com/jackwhelpton/fasthttp-routing/content"
"github.com/jackwhelpton/fasthttp-routing/fault"
"github.com/jackwhelpton/fasthttp-routing/file"
"github.com/valyala/fasthttp"
)
func main() {
router := routing.New()
router.Use(
// all these handlers are shared by every route
access.Logger(log.Printf),
slash.Remover(fasthttp.StatusMovedPermanently),
fault.Recovery(log.Printf),
)
// serve RESTful APIs
api := router.Group("/api")
api.Use(
// these handlers are shared by the routes in the api group only
content.TypeNegotiator(content.JSON, content.XML),
)
api.Get("/users", func(c *routing.Context) error {
return c.Write("user list")
})
api.Post("/users", func(c *routing.Context) error {
return c.Write("create a new user")
})
api.Put(`/users/<id:\d+>`, func(c *routing.Context) error {
return c.Write("update user " + c.Param("id"))
})
// serve index file
router.Get("/", file.Content("ui/index.html"))
// serve files under the "ui" subdirectory
router.Get("/*", file.Server(file.PathMap{
"/": "/ui/",
}))
fasthttp.ListenAndServe(":8080", router.HandleRequest)
}Create an HTML file ui/index.html with any content.
Now run the following command to start the Web server:
go run server.go
You should be able to access URLs such as http://localhost:8080, http://localhost:8080/api/users.
fasthttp-routing works by building a routing table in a router and then dispatching HTTP requests to the matching handlers found in the routing table. An intuitive illustration of a routing table is as follows:
| Routes | Handlers |
|---|---|
GET /users |
m1, m2, h1, ... |
POST /users |
m1, m2, h2, ... |
PUT /users/<id> |
m1, m2, h3, ... |
DELETE /users/<id> |
m1, m2, h4, ... |
For an incoming request GET /users, the first route would match and the handlers m1, m2, and h1 would be executed.
If the request is PUT /users/123, the third route would match and the corresponding handlers would be executed.
Note that the token <id> can match any number of non-slash characters and the matching part can be accessed as
a path parameter value in the handlers.
If an incoming request matches multiple routes in the table, the route added first to the table will take precedence. All other matching routes will be ignored.
The actual implementation of the routing table uses a variant of the radix tree data structure, which makes the routing process as fast as working with a hash table, thanks to the inspiration from httprouter.
To add a new route and its handlers to the routing table, call the To method like the following:
router := routing.New()
router.To("GET", "/users", m1, m2, h1)
router.To("POST", "/users", m1, m2, h2)You can also use shortcut methods, such as Get, Post, Put, etc., which are named after the HTTP method names:
router.Get("/users", m1, m2, h1)
router.Post("/users", m1, m2, h2)If you have multiple routes with the same URL path but different HTTP methods, like the above example, you can chain them together as follows,
router.Get("/users", m1, m2, h1).Post(m1, m2, h2)If you want to use the same set of handlers to handle the same URL path but different HTTP methods, you can take the following shortcut:
router.To("GET,POST", "/users", m1, m2, h)A route may contain parameter tokens which are in the format of <name:pattern>, where name stands for the parameter
name, and pattern is a regular expression which the parameter value should match. A token <name> is equivalent
to <name:[^/]*>, i.e., it matches any number of non-slash characters. At the end of a route, an asterisk character
can be used to match any number of arbitrary characters. Below are some examples:
/users/<username>: matches/users/admin/users/accnt-<id:\d+>: matches/users/accnt-123, but not/users/accnt-admin/users/<username>/*: matches/users/admin/profile/address
When a URL path matches a route, the matching parameters on the URL path can be accessed via Context.Param():
router := routing.New()
router.Get("/users/<username>", func (c *routing.Context) error {
fmt.Fprintf(c.Response, "Name: %v", c.Param("username"))
return nil
})Route group is a way of grouping together the routes which have the same route prefix. The routes in a group also
share the same handlers that are registered with the group via its Use method. For example,
router := routing.New()
api := router.Group("/api")
api.Use(m1, m2)
api.Get("/users", h1).Post(h2)
api.Put("/users/<id>", h3).Delete(h4)The above /api route group establishes the following routing table:
| Routes | Handlers |
|---|---|
GET /api/users |
m1, m2, h1, ... |
POST /api/users |
m1, m2, h2, ... |
PUT /api/users/<id> |
m1, m2, h3, ... |
DELETE /api/users/<id> |
m1, m2, h4, ... |
As you can see, all these routes have the same route prefix /api and the handlers m1 and m2. In other similar
routing frameworks, the handlers registered with a route group are also called middlewares.
Route groups can be nested. That is, a route group can create a child group by calling the Group() method. The router
serves as the top level route group. A child group inherits the handlers registered with its parent group. For example,
router := routing.New()
router.Use(m1)
api := router.Group("/api")
api.Use(m2)
users := api.Group("/users")
users.Use(m3)
users.Put("/<id>", h1)Because the router serves as the parent of the api group which is the parent of the users group,
the PUT /api/users/<id> route is associated with the handlers m1, m2, m3, and h1.
Router manages the routing table and dispatches incoming requests to appropriate handlers. A router instance is created
by calling the routing.New() method.
Because Router implements the http.Handler interface, it can be readily used to serve subtrees on existing Go servers.
For example,
router := routing.New()
http.Handle("/", router)
http.ListenAndServe(":8080", nil)A handler is a function with the signature func(*routing.Context) error. A handler is executed by the router if
the incoming request URL path matches the route that the handler is associated with. Through the routing.Context
parameter, you can access the request information in handlers.
A route may be associated with multiple handlers. These handlers will be executed in the order that they are registered to the route. The execution sequence can be terminated in the middle using one of the following two methods:
- A handler returns an error: the router will skip the rest of the handlers and handle the returned error.
- A handler calls
Context.Abort(): the router will simply skip the rest of the handlers. There is no error to be handled.
A handler can call Context.Next() to explicitly execute the rest of the unexecuted handlers and take actions after
they finish execution. For example, a response compression handler may start the output buffer, call Context.Next(),
and then compress and send the output to response.
For each incoming request, a routing.Context object is populated with the request information and passed through
the handlers that need to handle the request. Handlers can get the request information via Context.Request and
send a response back via Context.Response. The Context.Param() method allows handlers to access the URL path
parameters that match the current route.
Using Context.Get() and Context.Set(), handlers can share data between each other. For example, an authentication
handler can store the authenticated user identity by calling Context.Set(), and other handlers can retrieve back
the identity information by calling Context.Get().
Context provides a few shortcut methods to read query parameters. The Context.Query() method returns
the named URL query parameter value; the Context.PostForm() method returns the named parameter value in the POST or
PUT body parameters; and the Context.Form() method returns the value from either POST/PUT or URL query parameters.
The Context.Read() method supports reading data from the request body and populating it into an object.
The method will check the Content-Type HTTP header and parse the body data as the corresponding format.
For example, if Content-Type is application/json, the request body will be parsed as JSON data.
The public fields in the object being populated will receive the parsed data if the data contains the same named fields.
For example,
func foo(c *routing.Context) error {
data := &struct{
A string
B bool
}{}
// assume the body data is: {"A":"abc", "B":true}
// data will be populated as: {A: "abc", B: true}
if err := c.Read(&data); err != nil {
return err
}
}By default, Context supports reading data that are in JSON, XML, form, and multipart-form data.
You may modify routing.DataReaders to add support for other data formats.
Note that when the data is read as form data, you may use struct tag named form to customize
the name of the corresponding field in the form data. The form data reader also supports populating
data into embedded objects which are either named or anonymous.
The Context.Write() method can be used to write data of arbitrary type to the response.
By default, if the data being written is neither a string nor a byte array, the method will
will call fmt.Fprint() to write the data into the response.
You can call Context.SetWriter() to replace the default data writer with a customized one.
For example, the content.TypeNegotiator will negotiate the content response type and set the data
writer with an appropriate one.
A handler may return an error indicating some erroneous condition. Sometimes, a handler or the code it calls may cause
a panic. Both should be handled properly to ensure best user experience. It is recommended that you use
the fault.Recover handler or a similar error handler to handle these errors.
If an error is not handled by any handler, the router will handle it by calling its handleError() method which
simply sets an appropriate HTTP status code and writes the error message to the response.
When an incoming request has no matching route, the router will call the handlers registered via the Router.NotFound()
method. All the handlers registered via Router.Use() will also be called in advance. By default, the following two
handlers are registered with Router.NotFound():
routing.MethodNotAllowedHandler: a handler that sends anAllowHTTP header indicating the allowed HTTP methods for a requested URLrouting.NotFoundHandler: a handler triggering 404 HTTP error
Static files can be served with the help of file.Server and file.Content handlers. The former serves files
under the specified directories, while the latter serves the content of a single file. For example,
import (
"github.com/jackwhelpton/fasthttp-routing"
"github.com/jackwhelpton/fasthttp-routing/file"
)
router := routing.NewRouter()
// serve index file
router.Get("/", file.Content("ui/index.html"))
// serve files under the "ui" subdirectory
router.Get("/*", file.Server(file.PathMap{
"/": "/ui/",
}))A handler is a function with the signature func(*routing.Context) error. A handler is executed by the router if
the incoming request URL path matches the route that the handler is associated with. Through the routing.Context
parameter, you can access the request information in handlers.
A route may be associated with multiple handlers. These handlers will be executed in the order that they are registered to the route. The execution sequence can be terminated in the middle using one of the following two methods:
- A handler returns an error: the router will skip the rest of the handlers and handle the returned error.
- A handler calls
Context.Abort(): the router will simply skip the rest of the handlers. There is no error to be handled.
A handler can call Context.Next() to explicitly execute the rest of the unexecuted handlers and take actions after
they finish execution. For example, a response compression handler may start the output buffer, call Context.Next(),
and then compress and send the output to response.
fasthttp-routing comes with a few commonly used handlers in its subpackages:
| Handler name | Description |
|---|---|
| access.Logger | records an entry for every incoming request |
| auth.Basic | provides authentication via HTTP Basic |
| auth.Bearer | provides authentication via HTTP Bearer |
| auth.Query | provides authentication via token-based query parameter |
| auth.JWT | provides JWT-based authentication |
| content.TypeNegotiator | supports content negotiation by response types |
| content.LanguageNegotiator | supports content negotiation by accepted languages |
| cors.Handler | implements the CORS (Cross Origin Resource Sharing) specification from the W3C |
| fault.Recovery | recovers from panics and handles errors returned by handlers |
| fault.PanicHandler | recovers from panics happened in the handlers |
| fault.ErrorHandler | handles errors returned by handlers by writing them in an appropriate format to the response |
| file.Server | serves the files under the specified folder as response content |
| file.Content | serves the content of the specified file as the response |
| slash.Remover | removes the trailing slashes from the request URL and redirects to the proper URL |
The following code shows how these handlers may be used:
import (
"log"
"github.com/jackwhelpton/fasthttp-routing"
"github.com/jackwhelpton/fasthttp-routing/access"
"github.com/jackwhelpton/fasthttp-routing/fault"
"github.com/jackwhelpton/fasthttp-routing/slash"
"github.com/valyala/fasthttp"
)
router := routing.New()
router.Use(
access.Logger(log.Printf),
slash.Remover(fasthttp.StatusMovedPermanently),
fault.Recovery(log.Printf),
)