2017-09-14 13:55:39 +00:00
<!DOCTYPE HTML>
< html lang = "" >
< head >
< meta charset = "UTF-8" >
< meta content = "text/html; charset=utf-8" http-equiv = "Content-Type" >
< title > Parameter coercion · GitBook< / title >
< meta http-equiv = "X-UA-Compatible" content = "IE=edge" / >
< meta name = "description" content = "" >
< meta name = "generator" content = "GitBook 3.2.3" >
< link rel = "stylesheet" href = "gitbook/style.css" >
< link rel = "stylesheet" href = "gitbook/gitbook-plugin-highlight/website.css" >
< link rel = "stylesheet" href = "gitbook/gitbook-plugin-search/search.css" >
< link rel = "stylesheet" href = "gitbook/gitbook-plugin-fontsettings/website.css" >
< meta name = "HandheldFriendly" content = "true" / >
< meta name = "viewport" content = "width=device-width, initial-scale=1, user-scalable=no" >
< meta name = "apple-mobile-web-app-capable" content = "yes" >
< meta name = "apple-mobile-web-app-status-bar-style" content = "black" >
< link rel = "apple-touch-icon-precomposed" sizes = "152x152" href = "gitbook/images/apple-touch-icon-precomposed-152.png" >
< link rel = "shortcut icon" href = "gitbook/images/favicon.ico" type = "image/x-icon" >
< link rel = "next" href = "compiling_middleware.html" / >
2017-09-18 05:30:53 +00:00
< link rel = "prev" href = "dynamic_extensions.html" / >
2017-09-14 13:55:39 +00:00
< / head >
< body >
< div class = "book" >
< div class = "book-summary" >
< div id = "book-search-input" role = "search" >
< input type = "text" placeholder = "Type to search" / >
< / div >
< nav role = "navigation" >
< ul class = "summary" >
< li class = "chapter " data-level = "1.1" data-path = "./" >
< a href = "./" >
Introduction
< / a >
< / li >
< li class = "chapter " data-level = "1.2" >
< span >
2017-09-18 05:30:53 +00:00
Basics
2017-09-14 13:55:39 +00:00
< / span >
< ul class = "articles" >
2017-09-18 05:30:53 +00:00
< li class = "chapter " data-level = "1.2.1" data-path = "basics.html" >
2017-09-14 13:55:39 +00:00
2017-09-18 05:30:53 +00:00
< a href = "basics.html#route-syntax" >
2017-09-14 13:55:39 +00:00
Route syntax
< / a >
< / li >
2017-09-18 05:30:53 +00:00
< li class = "chapter " data-level = "1.2.2" data-path = "basics.html" >
2017-09-14 13:55:39 +00:00
2017-09-18 05:30:53 +00:00
< a href = "basics.html#router" >
2017-09-14 13:55:39 +00:00
2017-09-18 05:30:53 +00:00
Router
2017-09-14 13:55:39 +00:00
< / a >
< / li >
2017-09-18 05:30:53 +00:00
< li class = "chapter " data-level = "1.2.3" data-path = "basics.html" >
2017-09-14 13:55:39 +00:00
2017-09-18 05:30:53 +00:00
< a href = "basics.html#path-based-routing" >
2017-09-14 13:55:39 +00:00
2017-09-18 05:30:53 +00:00
Path-based Routing
2017-09-14 13:55:39 +00:00
< / a >
< / li >
2017-09-18 05:30:53 +00:00
< li class = "chapter " data-level = "1.2.4" data-path = "basics.html" >
2017-09-14 13:55:39 +00:00
2017-09-18 05:30:53 +00:00
< a href = "basics.html#name-based-routing" >
2017-09-14 13:55:39 +00:00
2017-09-18 05:30:53 +00:00
Name-based Routing
2017-09-14 13:55:39 +00:00
< / a >
< / li >
2017-09-18 05:30:53 +00:00
< li class = "chapter " data-level = "1.2.5" data-path = "basics.html" >
< a href = "basics.html#route-data" >
Route data
< / a >
2017-09-14 13:55:39 +00:00
< / li >
2017-09-18 05:30:53 +00:00
< li class = "chapter " data-level = "1.2.6" data-path = "basics.html" >
2017-09-14 13:55:39 +00:00
2017-09-18 05:30:53 +00:00
< a href = "basics.html#different-routers" >
2017-09-14 13:55:39 +00:00
2017-09-18 05:30:53 +00:00
Different Routers
2017-09-14 13:55:39 +00:00
< / a >
< / li >
2017-09-18 05:30:53 +00:00
< / ul >
2017-09-14 13:55:39 +00:00
2017-09-18 05:30:53 +00:00
< / li >
< li class = "chapter " data-level = "1.3" >
< span >
2017-09-14 13:55:39 +00:00
2017-09-18 05:30:53 +00:00
Advanced
2017-09-14 13:55:39 +00:00
2017-09-18 05:30:53 +00:00
< / span >
2017-09-14 13:55:39 +00:00
2017-09-18 05:30:53 +00:00
< ul class = "articles" >
2017-09-14 13:55:39 +00:00
2017-09-18 05:30:53 +00:00
< li class = "chapter " data-level = "1.3.1" data-path = "route_conflicts.html" >
2017-09-14 13:55:39 +00:00
2017-09-18 05:30:53 +00:00
< a href = "route_conflicts.html" >
2017-09-14 13:55:39 +00:00
2017-09-18 05:30:53 +00:00
Route conflicts
2017-09-14 13:55:39 +00:00
< / a >
< / li >
2017-09-18 05:30:53 +00:00
< li class = "chapter " data-level = "1.3.2" data-path = "route_validation.html" >
2017-09-14 13:55:39 +00:00
2017-09-18 05:30:53 +00:00
< a href = "route_validation.html" >
2017-09-14 13:55:39 +00:00
2017-09-18 05:30:53 +00:00
Route Validation
2017-09-14 13:55:39 +00:00
< / a >
< / li >
2017-09-18 05:30:53 +00:00
< li class = "chapter " data-level = "1.3.3" data-path = "configuring_routers.html" >
2017-09-14 13:55:39 +00:00
< a href = "configuring_routers.html" >
Configuring routers
< / a >
< / li >
2017-09-18 05:30:53 +00:00
< / ul >
< / li >
< li class = "chapter " data-level = "1.4" >
2017-09-14 13:55:39 +00:00
< span >
2017-09-18 05:30:53 +00:00
Ring
2017-09-14 13:55:39 +00:00
< / span >
2017-09-18 05:30:53 +00:00
< ul class = "articles" >
< li class = "chapter " data-level = "1.4.1" data-path = "ring.html" >
< a href = "ring.html" >
Ring-router
< / a >
< / li >
< li class = "chapter " data-level = "1.4.2" data-path = "dynamic_extensions.html" >
< a href = "dynamic_extensions.html" >
Dynamic extensions
< / a >
< / li >
< li class = "chapter active" data-level = "1.4.3" data-path = "parameter_coercion.html" >
< a href = "parameter_coercion.html" >
Parameter coercion
< / a >
< / li >
< li class = "chapter " data-level = "1.4.4" data-path = "compiling_middleware.html" >
< a href = "compiling_middleware.html" >
Compiling middleware
< / a >
< / li >
< / ul >
2017-09-14 13:55:39 +00:00
< / li >
2017-09-18 05:30:53 +00:00
< li class = "chapter " data-level = "1.5" >
2017-09-14 13:55:39 +00:00
< span >
TODO: Swagger & OpenAPI
< / span >
< / li >
2017-09-18 05:30:53 +00:00
< li class = "chapter " data-level = "1.6" >
2017-09-14 13:55:39 +00:00
< span >
TODO: Interceptors
< / span >
< / li >
< li class = "divider" > < / li >
< li >
< a href = "https://www.gitbook.com" target = "blank" class = "gitbook-link" >
Published with GitBook
< / a >
< / li >
< / ul >
< / nav >
< / div >
< div class = "book-body" >
< div class = "body-inner" >
< div class = "book-header" role = "navigation" >
<!-- Title -->
< h1 >
< i class = "fa fa-circle-o-notch fa-spin" > < / i >
< a href = "." > Parameter coercion< / a >
< / h1 >
< / div >
< div class = "page-wrapper" tabindex = "-1" role = "main" >
< div class = "page-inner" >
< div id = "book-search-results" >
< div class = "search-noresults" >
< section class = "normal markdown-section" >
< h1 id = "parameter-coercion" > Parameter coercion< / h1 >
< p > Reitit provides pluggable parameter coercion via < code > reitit.coercion.protocol/Coercion< / code > protocol, originally introduced in < a href = "https://clojars.org/metosin/compojure-api" target = "_blank" > compojure-api< / a > . Reitit ships with < code > reitit.coercion.spec/SpecCoercion< / code > providing implemenation for < a href = "https://clojure.org/about/spec" target = "_blank" > clojure.spec< / a > and < a href = "https://github.com/metosin/spec-tools#data-specs" target = "_blank" > data-specs< / a > .< / p >
< p > < strong > NOTE< / strong > : Before Clojure 1.9.0 is shipped, to use the spec-coercion, one needs to add the following dependencies manually to the project:< / p >
< pre > < code class = "lang-clj" > [org.clojure/clojure < span class = "hljs-string" > " 1.9.0-alpha20" < / span > ]
[org.clojure/spec.alpha < span class = "hljs-string" > " 0.1.123" < / span > ]
[metosin/spec-tools < span class = "hljs-string" > " 0.3.3" < / span > ]
< / code > < / pre >
< h3 id = "ring-request-and-response-coercion" > Ring request and response coercion< / h3 >
< p > To use < code > Coercion< / code > with Ring, one needs to do the following:< / p >
< ol >
< li > Define parameters and responses as data into route meta-data, in format adopted from < a href = "https://github.com/metosin/ring-swagger#more-complete-example" target = "_blank" > ring-swagger< / a > :< ul >
< li > < code > :parameters< / code > map, with submaps for different parameters: < code > :query< / code > , < code > :body< / code > , < code > :form< / code > , < code > :header< / code > and < code > :path< / code > . Parameters are defined in the format understood by the < code > Coercion< / code > .< / li >
< li > < code > :responses< / code > map, with response status codes as keys (or < code > :default< / code > for " everything else" ) with maps with < code > :schema< / code > and optionally < code > :description< / code > as values.< / li >
< / ul >
< / li >
< li > Define a < code > Coercion< / code > to route meta-data under < code > :coercion< / code > < / li >
< li > Mount request & response coercion middleware to the routes.< / li >
< / ol >
< p > If the request coercion succeeds, the coerced parameters are injected into request under < code > :parameters< / code > .< / p >
< p > If either request or response coercion fails, an descriptive error is thrown.< / p >
< h4 id = "example-with-data-specs" > Example with data-specs< / h4 >
< pre > < code class = "lang-clj" > (< span class = "hljs-name" > require< / span > ' [reitit.ring < span class = "hljs-symbol" > :as< / span > ring])
(< span class = "hljs-name" > require< / span > ' [reitit.coercion < span class = "hljs-symbol" > :as< / span > coercion])
(< span class = "hljs-name" > require< / span > ' [reitit.coercion.spec < span class = "hljs-symbol" > :as< / span > spec])
(< span class = "hljs-name" > < span class = "hljs-builtin-name" > def< / span > < / span > app
(< span class = "hljs-name" > ring/ring-handler< / span >
(< span class = "hljs-name" > ring/router< / span >
[< span class = "hljs-string" > " /api" < / span >
[< span class = "hljs-string" > " /ping" < / span > {< span class = "hljs-symbol" > :parameters< / span > {< span class = "hljs-symbol" > :body< / span > {< span class = "hljs-symbol" > :x< / span > int?, < span class = "hljs-symbol" > :y< / span > int?}}
< span class = "hljs-symbol" > :responses< / span > {< span class = "hljs-number" > 200< / span > {< span class = "hljs-symbol" > :schema< / span > {< span class = "hljs-symbol" > :total< / span > pos-int?}}}
< span class = "hljs-symbol" > :get< / span > {< span class = "hljs-symbol" > :handler< / span > (< span class = "hljs-name" > < span class = "hljs-builtin-name" > fn< / span > < / span > [{{{< span class = "hljs-symbol" > :keys< / span > [x y]} < span class = "hljs-symbol" > :body< / span > } < span class = "hljs-symbol" > :parameters< / span > }]
{< span class = "hljs-symbol" > :status< / span > < span class = "hljs-number" > 200< / span >
< span class = "hljs-symbol" > :body< / span > {< span class = "hljs-symbol" > :total< / span > (< span class = "hljs-name" > < span class = "hljs-builtin-name" > +< / span > < / span > x y)}})}}]]
{< span class = "hljs-symbol" > :meta< / span > {< span class = "hljs-symbol" > :middleware< / span > [coercion/gen-wrap-coerce-parameters
coercion/gen-wrap-coerce-response]
< span class = "hljs-symbol" > :coercion< / span > spec/coercion}})))
< / code > < / pre >
< pre > < code class = "lang-clj" > (< span class = "hljs-name" > app< / span >
{< span class = "hljs-symbol" > :request-method< / span > < span class = "hljs-symbol" > :get< / span >
< span class = "hljs-symbol" > :uri< / span > < span class = "hljs-string" > " /api/ping" < / span >
< span class = "hljs-symbol" > :body-params< / span > {< span class = "hljs-symbol" > :x< / span > < span class = "hljs-number" > 1< / span > , < span class = "hljs-symbol" > :y< / span > < span class = "hljs-number" > 2< / span > }})
< span class = "hljs-comment" > ; {:status 200, :body {:total 3}}< / span >
< / code > < / pre >
< h4 id = "example-with-specs" > Example with specs< / h4 >
< pre > < code class = "lang-clj" > (< span class = "hljs-name" > require< / span > ' [reitit.ring < span class = "hljs-symbol" > :as< / span > ring])
(< span class = "hljs-name" > require< / span > ' [reitit.coercion < span class = "hljs-symbol" > :as< / span > coercion])
(< span class = "hljs-name" > require< / span > ' [reitit.coercion.spec < span class = "hljs-symbol" > :as< / span > spec])
(< span class = "hljs-name" > require< / span > ' [clojure.spec.alpha < span class = "hljs-symbol" > :as< / span > s])
(< span class = "hljs-name" > require< / span > ' [spec-tools.core < span class = "hljs-symbol" > :as< / span > st])
2017-09-14 14:40:31 +00:00
(< span class = "hljs-name" > s/def< / span > < span class = "hljs-symbol" > ::x< / span > (< span class = "hljs-name" > st/spec< / span > int?))
(< span class = "hljs-name" > s/def< / span > < span class = "hljs-symbol" > ::y< / span > (< span class = "hljs-name" > st/spec< / span > int?))
(< span class = "hljs-name" > s/def< / span > < span class = "hljs-symbol" > ::total< / span > int?)
(< span class = "hljs-name" > s/def< / span > < span class = "hljs-symbol" > ::request< / span > (< span class = "hljs-name" > s/keys< / span > < span class = "hljs-symbol" > :req-un< / span > [< span class = "hljs-symbol" > ::x< / span > < span class = "hljs-symbol" > ::y< / span > ]))
(< span class = "hljs-name" > s/def< / span > < span class = "hljs-symbol" > ::response< / span > (< span class = "hljs-name" > s/keys< / span > < span class = "hljs-symbol" > :req-un< / span > [< span class = "hljs-symbol" > ::total< / span > ]))
2017-09-14 13:55:39 +00:00
(< span class = "hljs-name" > < span class = "hljs-builtin-name" > def< / span > < / span > app
(< span class = "hljs-name" > ring/ring-handler< / span >
(< span class = "hljs-name" > ring/router< / span >
[< span class = "hljs-string" > " /api" < / span >
2017-09-14 14:40:31 +00:00
[< span class = "hljs-string" > " /ping" < / span > {< span class = "hljs-symbol" > :parameters< / span > {< span class = "hljs-symbol" > :body< / span > < span class = "hljs-symbol" > ::request< / span > }
< span class = "hljs-symbol" > :responses< / span > {< span class = "hljs-number" > 200< / span > {< span class = "hljs-symbol" > :schema< / span > < span class = "hljs-symbol" > ::response< / span > }}
2017-09-14 13:55:39 +00:00
< span class = "hljs-symbol" > :get< / span > {< span class = "hljs-symbol" > :handler< / span > (< span class = "hljs-name" > < span class = "hljs-builtin-name" > fn< / span > < / span > [{{{< span class = "hljs-symbol" > :keys< / span > [x y]} < span class = "hljs-symbol" > :body< / span > } < span class = "hljs-symbol" > :parameters< / span > }]
{< span class = "hljs-symbol" > :status< / span > < span class = "hljs-number" > 200< / span >
< span class = "hljs-symbol" > :body< / span > {< span class = "hljs-symbol" > :total< / span > (< span class = "hljs-name" > < span class = "hljs-builtin-name" > +< / span > < / span > x y)}})}}]]
{< span class = "hljs-symbol" > :meta< / span > {< span class = "hljs-symbol" > :middleware< / span > [coercion/gen-wrap-coerce-parameters
coercion/gen-wrap-coerce-response]
< span class = "hljs-symbol" > :coercion< / span > spec/coercion}})))
< / code > < / pre >
< pre > < code class = "lang-clj" > (< span class = "hljs-name" > app< / span >
{< span class = "hljs-symbol" > :request-method< / span > < span class = "hljs-symbol" > :get< / span >
< span class = "hljs-symbol" > :uri< / span > < span class = "hljs-string" > " /api/ping" < / span >
< span class = "hljs-symbol" > :body-params< / span > {< span class = "hljs-symbol" > :x< / span > < span class = "hljs-number" > 1< / span > , < span class = "hljs-symbol" > :y< / span > < span class = "hljs-number" > 2< / span > }})
< span class = "hljs-comment" > ; {:status 200, :body {:total 3}}< / span >
< / code > < / pre >
< / section >
< / div >
< div class = "search-results" >
< div class = "has-results" >
< h1 class = "search-results-title" > < span class = 'search-results-count' > < / span > results matching "< span class = 'search-query' > < / span > "< / h1 >
< ul class = "search-results-list" > < / ul >
< / div >
< div class = "no-results" >
< h1 class = "search-results-title" > No results matching "< span class = 'search-query' > < / span > "< / h1 >
< / div >
< / div >
< / div >
< / div >
< / div >
< / div >
2017-09-18 05:30:53 +00:00
< a href = "dynamic_extensions.html" class = "navigation navigation-prev " aria-label = "Previous page: Dynamic extensions" >
2017-09-14 13:55:39 +00:00
< i class = "fa fa-angle-left" > < / i >
< / a >
< a href = "compiling_middleware.html" class = "navigation navigation-next " aria-label = "Next page: Compiling middleware" >
< i class = "fa fa-angle-right" > < / i >
< / a >
< / div >
< script >
var gitbook = gitbook || [];
gitbook.push(function() {
2017-10-02 14:57:12 +00:00
gitbook.page.hasChanged({"page":{"title":"Parameter coercion","level":"1.4.3","depth":2,"next":{"title":"Compiling middleware","level":"1.4.4","depth":2,"path":"compiling_middleware.md","ref":"compiling_middleware.md","articles":[]},"previous":{"title":"Dynamic extensions","level":"1.4.2","depth":2,"path":"dynamic_extensions.md","ref":"dynamic_extensions.md","articles":[]},"dir":"ltr"},"config":{"plugins":["editlink","github","highlight"],"root":"doc","styles":{"website":"styles/website.css","pdf":"styles/pdf.css","epub":"styles/epub.css","mobi":"styles/mobi.css","ebook":"styles/ebook.css","print":"styles/print.css"},"pluginsConfig":{"editlink":{"label":"Edit This Page","multilingual":false,"base":"https://github.com/metosin/reitit/tree/master/doc"},"github":{"url":"https://github.com/metosin/reitit"},"highlight":{},"search":{},"lunr":{"maxIndexSize":1000000,"ignoreSpecialCharacters":false},"sharing":{"facebook":true,"twitter":true,"google":false,"weibo":false,"instapaper":false,"vk":false,"all":["facebook","google","twitter","weibo","instapaper"]},"fontsettings":{"theme":"white","family":"sans","size":2},"theme-default":{"styles":{"website":"styles/website.css","pdf":"styles/pdf.css","epub":"styles/epub.css","mobi":"styles/mobi.css","ebook":"styles/ebook.css","print":"styles/print.css"},"showLevel":false}},"theme":"default","pdf":{"pageNumbers":true,"fontSize":12,"fontFamily":"Arial","paperSize":"a4","chapterMark":"pagebreak","pageBreaksBefore":"/","margin":{"right":62,"left":62,"top":56,"bottom":56}},"structure":{"langs":"LANGS.md","readme":"README.md","glossary":"GLOSSARY.md","summary":"SUMMARY.md"},"variables":{},"gitbook":"*"},"file":{"path":"parameter_coercion.md","mtime":"2017-10-02T14:56:41.014Z","type":"markdown"},"gitbook":{"version":"3.2.3","time":"2017-10-02T14:57:10.957Z"},"basePath":".","book":{"language":""}});
2017-09-14 13:55:39 +00:00
});
< / script >
< / div >
< script src = "gitbook/gitbook.js" > < / script >
< script src = "gitbook/theme.js" > < / script >
< script src = "gitbook/gitbook-plugin-editlink/plugin.js" > < / script >
< script src = "gitbook/gitbook-plugin-github/plugin.js" > < / script >
< script src = "gitbook/gitbook-plugin-search/search-engine.js" > < / script >
< script src = "gitbook/gitbook-plugin-search/search.js" > < / script >
< script src = "gitbook/gitbook-plugin-lunr/lunr.min.js" > < / script >
< script src = "gitbook/gitbook-plugin-lunr/search-lunr.js" > < / script >
< script src = "gitbook/gitbook-plugin-sharing/buttons.js" > < / script >
< script src = "gitbook/gitbook-plugin-fontsettings/fontsettings.js" > < / script >
< / body >
< / html >