trout
2016-01-02
Parent:6c6ea726570a
trout/doc.go
Fix bug in handling of finding closest match for params. We had a bug that finding the closest match for params would only work if the parent was also a param. This lead to problems where multiple methods declared on a single endpoint as follows were treated as multiple endpoints: router.Endpoint("/{id}").Methods("GET").Handler(handleGet) router.Endpoint("/{id}").Methods("POST").Handler(handlePost) This caused erroneous Method Not Allowed errors, as the POST method would be part of an Endpoint that could never be routed to. We also discovered that Method Not Allowed errors weren't returning the required Allow header with a list of acceptable methods, so this has been fixed.
1 /*
2 Package trout provides an opinionated router that's implemented
3 using a basic trie.
5 The router is opinionated and biased towards basic RESTful
6 services. Its main constraint is that its URL templating is very
7 basic and has no support for regular expressions, prefix matching,
8 or anything other than a direct equality comparison, unlike many
9 routing libraries.
11 The router is specifically designed to support users that want to
12 return correct information with HEAD requests, so it enables users
13 to retrieve a list of HTTP methods an Endpoint is configured to
14 respond to. It will not return the configurations an Endpoint is
15 implicitly configured to respond to by associated a Handler with the
16 Endpoint itself. These HTTP methods can be accessed through the
17 Trout-Methods header that is injected into the http.Request object.
18 Each method will be its own string in the slice.
20 The router is also specifically designed to differentiate between a
21 404 (Not Found) response and a 405 (Method Not Allowed) response. It
22 will use the configured Handle404 http.Handler when no Endpoint is found
23 that matches the http.Request's Path property. It will use the
24 configured Handle405 http.Handler when an Endpoint is found for the
25 http.Request's Path, but the http.Request's Method has no Handler
26 associated with it. Setting a default http.Handler for the Endpoint will
27 result in the Handle405 http.Handler never being used for that Endpoint.
29 To map an Endpoint to a http.Handler:
31 var router trout.Router
32 router.Endpoint("/posts/{slug}/comments/{id}").Handler(postsHandler)
34 All requests that match that URL structure will be passed to the postsHandler,
35 no matter what HTTP method they use.
37 To map specific Methods to a http.Handler:
39 var router trout.Router
40 router.Endpoint("/posts/{slug}").Methods("GET", "POST").Handler(postsHandler)
42 Only requests that match that URL structure will be passed to the postsHandler,
43 and only if they use the GET or POST HTTP method.
45 To access the URL parameter values inside a request, use the RequestVars helper:
47 func handler(w http.ResponseWriter, r *http.Request) {
48 vars := trout.RequestVars(r)
49 ...
50 }
52 This will return an http.Header object containing the parameter values. They are
53 passed into the http.Handler by injecting them into the http.Request's Header property,
54 with the header key of "Trout-Params-{parameter}". The RequestVars helper is just a
55 convenience function to strip the prefix. Parameters are always passed without the curly
56 braces. Finally, if a parameter name is used multiple times in a single URL template, values
57 will be stored in the slice in the order they appeared in the template:
59 // for the template /posts/{id}/comments/{id}
60 // filled with /posts/hello-world/comments/1
61 vars := trout.RequestVars(r)
62 fmt.Println(vars.Get("id")) // outputs `hello-world`
63 fmt.Println(vars[http.CanonicalHeaderKey("id")]) // outputs `["hello-world", "1"]`
64 fmt.Println(vars[http.CanonicalHeaderKey("id"})][1]) // outputs `1`
65 */
66 package trout