io.vertx.ext.web

## Interface RoutingContext

-     public interface RoutingContext

  Represents the context for the handling of a request in Vert.x-Web.

  A new instance is created for each HTTP request that is received in the `Router.accept(HttpServerRequest)` of the router.

  The same instance is passed to any matching request or failure handlers during the routing of the request or failure.

  The context provides access to the `HttpServerRequest` and `HttpServerResponse` and allows you to maintain arbitrary data that lives for the lifetime of the context. Contexts are discarded once they have been routed to the handler for the request.

  The context also provides access to the `Session`, cookies and body for the request, given the correct handlers in the application.

  Author:
    Tim Fox

- - ### Method Summary

    All Methods Instance Methods Abstract Methods Default Methods
    Modifier and Type | Method and Description
    --- | ---
    `List<Locale>` | `acceptableLocales()` Returns the locales for the current request.
    `int` | `addBodyEndHandler(Handler<Void> handler)` Provides a handler that will be called after the last part of the body is written to the wire.
    `RoutingContext` | `addCookie(Cookie cookie)` Add a cookie.
    `int` | `addHeadersEndHandler(Handler<Void> handler)` Add a handler that will be called just before headers are written to the response.
    `void` | `clearUser()` Clear the current user object in the context.
    `int` | `cookieCount()`
    `Set<Cookie>` | `cookies()`
    `Route` | `currentRoute()`
    `Map<String,Object>` | `data()`
    `void` | `fail(int statusCode)` Fail the context with the specified status code.
    `void` | `fail(Throwable throwable)` Fail the context with the specified throwable.
    `boolean` | `failed()`
    `Throwable` | `failure()` If the context is being routed to failure handlers after a failure has been triggered by calling `fail(Throwable)` then this will return that throwable.
    `Set<FileUpload>` | `fileUploads()`
    `<T> T` | `get(String key)` Get some data from the context.
    `String` | `getAcceptableContentType()` If the route specifies produces matches, e.g.
    `Buffer` | `getBody()`
    `JsonObject` | `getBodyAsJson()`
    `JsonArray` | `getBodyAsJsonArray()`
    `String` | `getBodyAsString()`
    `String` | `getBodyAsString(String encoding)` Get the entire HTTP request body as a string, assuming the specified encoding.
    `Cookie` | `getCookie(String name)` Get the cookie with the specified name.
    `String` | `mountPoint()`
    `void` | `next()` Tell the router to route this context to the next matching route (if any).
    `String` | `normalisedPath()` Return the normalised path for the request.
    `String` | `pathParam(String name)` Gets the value of a single path parameter
    `Map<String,String>` | `pathParams()` Returns a map of named parameters as defined in path declaration with their actual values
    `default Locale` | `preferredLocale()` Helper to return the user preferred locale.
    `RoutingContext` | `put(String key, Object obj)` Put some arbitrary data in the context.
    `<T> T` | `remove(String key)` Remove some data from the context.
    `boolean` | `removeBodyEndHandler(int handlerID)` Remove a body end handler
    `Cookie` | `removeCookie(String name)` Remove a cookie.
    `boolean` | `removeHeadersEndHandler(int handlerID)` Remove a headers end handler
    `HttpServerRequest` | `request()`
    `void` | `reroute(HttpMethod method, String path)` Restarts the current router with a new method and path.
    `default void` | `reroute(String path)` Restarts the current router with a new path and reusing the original method.
    `HttpServerResponse` | `response()`
    `Session` | `session()` Get the session.
    `void` | `setAcceptableContentType(String contentType)` Set the acceptable content type.
    `void` | `setBody(Buffer body)` Set the body.
    `void` | `setSession(Session session)` Set the session.
    `void` | `setUser(User user)` Set the user.
    `int` | `statusCode()` If the context is being routed to failure handlers after a failure has been triggered by calling `fail(int)` then this will return that status code.
    `User` | `user()` Get the authenticated user (if any).
    `Vertx` | `vertx()`

- - ### Method Detail

    - #### request

          HttpServerRequest request()

      Returns:
        the HTTP request object

    - #### response

          HttpServerResponse response()

      Returns:
        the HTTP response object

    - #### next

          void next()

      Tell the router to route this context to the next matching route (if any). This method, if called, does not need to be called during the execution of the handler, it can be called some arbitrary time later, if required.

      If next is not called for a handler then the handler should make sure it ends the response or no response will be sent.

    - #### fail

          void fail(int statusCode)

      Fail the context with the specified status code.

      This will cause the router to route the context to any matching failure handlers for the request. If no failure handlers match a default failure response will be sent.

      Parameters:
        `statusCode` - the HTTP status code

    - #### fail

          void fail(Throwable throwable)

      Fail the context with the specified throwable.

      This will cause the router to route the context to any matching failure handlers for the request. If no failure handlers match a default failure response with status code 500 will be sent.

      Parameters:
        `throwable` - a throwable representing the failure

    - #### put

          RoutingContext put(String key,
                             Object obj)

      Put some arbitrary data in the context. This will be available in any handlers that receive the context.
      Parameters:
        `key` - the key for the data
        `obj` - the data
      Returns:
        a reference to this, so the API can be used fluently

    - #### get

          <T> T get(String key)

      Get some data from the context. The data is available in any handlers that receive the context.
      Type Parameters:
        `T` - the type of the data
      Parameters:
        `key` - the key for the data
      Returns:
        the data
      Throws:
        `ClassCastException` - if the data is not of the expected type

    - #### remove

          <T> T remove(String key)

      Remove some data from the context. The data is available in any handlers that receive the context.
      Type Parameters:
        `T` - the type of the data
      Parameters:
        `key` - the key for the data
      Returns:
        the previous data associated with the key
      Throws:
        `ClassCastException` - if the data is not of the expected type

    - #### data

          Map<String,Object> data()

      Returns:
        all the context data as a map

    - #### vertx

          Vertx vertx()

      Returns:
        the Vert.x instance associated to the initiating `Router` for this context

    - #### mountPoint

          String mountPoint()

      Returns:
        the mount point for this router. It will be null for a top level router. For a sub-router it will be the path at which the subrouter was mounted.

    - #### currentRoute

          Route currentRoute()

      Returns:
        the current route this context is being routed through.

    - #### normalisedPath

          String normalisedPath()

      Return the normalised path for the request.

      The normalised path is where the URI path has been decoded, i.e. any unicode or other illegal URL characters that were encoded in the original URL with `%` will be returned to their original form. E.g. `%20` will revert to a space. Also `+` reverts to a space in a query.

      The normalised path will also not contain any `..` character sequences to prevent resources being accessed outside of the permitted area.

      It's recommended to always use the normalised path as opposed to `HttpServerRequest.path()` if accessing server resources requested by a client.

      Returns:
        the normalised path

    - #### getCookie

          Cookie getCookie(String name)

      Get the cookie with the specified name. The context must have first been routed to a `CookieHandler` for this to work.
      Parameters:
        `name` - the cookie name
      Returns:
        the cookie

    - #### addCookie

          RoutingContext addCookie(Cookie cookie)

      Add a cookie. This will be sent back to the client in the response. The context must have first been routed to a `CookieHandler` for this to work.
      Parameters:
        `cookie` - the cookie
      Returns:
        a reference to this, so the API can be used fluently

    - #### removeCookie

          Cookie removeCookie(String name)

      Remove a cookie. The context must have first been routed to a `CookieHandler` for this to work.
      Parameters:
        `name` - the name of the cookie
      Returns:
        the cookie, if it existed, or null

    - #### cookieCount

          int cookieCount()

      Returns:
        the number of cookies. The context must have first been routed to a `CookieHandler` for this to work.

    - #### cookies

          Set<Cookie> cookies()

      Returns:
        a set of all the cookies. The context must have first been routed to a `CookieHandler` for this to be populated.

    - #### getBodyAsString

          String getBodyAsString()

      Returns:
        the entire HTTP request body as a string, assuming UTF-8 encoding. The context must have first been routed to a `BodyHandler` for this to be populated.

    - #### getBodyAsString

          String getBodyAsString(String encoding)

      Get the entire HTTP request body as a string, assuming the specified encoding. The context must have first been routed to a `BodyHandler` for this to be populated.
      Parameters:
        `encoding` - the encoding, e.g. "UTF-16"
      Returns:
        the body

    - #### getBodyAsJson

          JsonObject getBodyAsJson()

      Returns:
        Get the entire HTTP request body as a `JsonObject`. The context must have first been routed to a `BodyHandler` for this to be populated.

    - #### getBodyAsJsonArray

          JsonArray getBodyAsJsonArray()

      Returns:
        Get the entire HTTP request body as a `JsonArray`. The context must have first been routed to a `BodyHandler` for this to be populated.

    - #### getBody

          Buffer getBody()

      Returns:
        Get the entire HTTP request body as a `Buffer`. The context must have first been routed to a `BodyHandler` for this to be populated.

    - #### fileUploads

          Set<FileUpload> fileUploads()

      Returns:
        a set of fileuploads (if any) for the request. The context must have first been routed to a `BodyHandler` for this to work.

    - #### session

          Session session()

      Get the session. The context must have first been routed to a `SessionHandler` for this to be populated. Sessions live for a browser session, and are maintained by session cookies.
      Returns:
        the session.

    - #### user

          User user()

      Get the authenticated user (if any). This will usually be injected by an auth handler if authentication if successful.
      Returns:
        the user, or null if the current user is not authenticated.

    - #### failure

          Throwable failure()

      If the context is being routed to failure handlers after a failure has been triggered by calling `fail(Throwable)` then this will return that throwable. It can be used by failure handlers to render a response, e.g. create a failure response page.
      Returns:
        the throwable used when signalling failure

    - #### statusCode

          int statusCode()

      If the context is being routed to failure handlers after a failure has been triggered by calling `fail(int)` then this will return that status code. It can be used by failure handlers to render a response, e.g. create a failure response page. When the status code has not been set yet (it is undefined) its value will be -1.
      Returns:
        the status code used when signalling failure

    - #### getAcceptableContentType

          String getAcceptableContentType()

      If the route specifies produces matches, e.g. produces `text/html` and `text/plain`, and the `accept` header matches one or more of these then this returns the most acceptable match.
      Returns:
        the most acceptable content type.

    - #### addHeadersEndHandler

          int addHeadersEndHandler(Handler<Void> handler)

      Add a handler that will be called just before headers are written to the response. This gives you a hook where you can write any extra headers before the response has been written when it will be too late.
      Parameters:
        `handler` - the handler
      Returns:
        the id of the handler. This can be used if you later want to remove the handler.

    - #### removeHeadersEndHandler

          boolean removeHeadersEndHandler(int handlerID)

      Remove a headers end handler
      Parameters:
        `handlerID` - the id as returned from `addHeadersEndHandler(Handler)`.
      Returns:
        true if the handler existed and was removed, false otherwise

    - #### addBodyEndHandler

          int addBodyEndHandler(Handler<Void> handler)

      Provides a handler that will be called after the last part of the body is written to the wire. The handler is called asynchronously of when the response has been received by the client. This provides a hook allowing you to do more operations once the request has been sent over the wire such as resource cleanup.
      Parameters:
        `handler` - the handler
      Returns:
        the id of the handler. This can be used if you later want to remove the handler.

    - #### removeBodyEndHandler

          boolean removeBodyEndHandler(int handlerID)

      Remove a body end handler
      Parameters:
        `handlerID` - the id as returned from `addBodyEndHandler(Handler)`.
      Returns:
        true if the handler existed and was removed, false otherwise

    - #### failed

          boolean failed()

      Returns:
        true if the context is being routed to failure handlers.

    - #### setBody

          void setBody(Buffer body)

      Set the body. Used by the `BodyHandler`. You will not normally call this method.
      Parameters:
        `body` - the body

    - #### setSession

          void setSession(Session session)

      Set the session. Used by the `SessionHandler`. You will not normally call this method.
      Parameters:
        `session` - the session

    - #### setUser

          void setUser(User user)

      Set the user. Usually used by auth handlers to inject a User. You will not normally call this method.
      Parameters:
        `user` - the user

    - #### clearUser

          void clearUser()

      Clear the current user object in the context. This usually is used for implementing a log out feature, since the current user is unbounded from the routing context.

    - #### setAcceptableContentType

          void setAcceptableContentType(String contentType)

      Set the acceptable content type. Used by
      Parameters:
        `contentType` - the content type

    - #### reroute

          default void reroute(String path)

      Restarts the current router with a new path and reusing the original method. All path parameters are then parsed and available on the params list.
      Parameters:
        `path` - the new http path.

    - #### reroute

          void reroute(HttpMethod method,
                       String path)

      Restarts the current router with a new method and path. All path parameters are then parsed and available on the params list.
      Parameters:
        `method` - the new http request
        `path` - the new http path.

    - #### acceptableLocales

          List<Locale> acceptableLocales()

      Returns the locales for the current request. The locales are determined from the `accept-languages` header and sorted on quality. When 2 or more entries have the same quality then the order used to return the best match is based on the lowest index on the original list. For example if a user has en-US and en-GB with same quality and this order the best match will be en-US because it was declared as first entry by the client.
      Returns:
        the best matched locale for the request

    - #### preferredLocale

          default Locale preferredLocale()

      Helper to return the user preferred locale. It is the same action as returning the first element of the acceptable locales.
      Returns:
        the users preferred locale.

    - #### pathParams

          Map<String,String> pathParams()

      Returns a map of named parameters as defined in path declaration with their actual values
      Returns:
        the map of named parameters

    - #### pathParam

          String pathParam(String name)

      Gets the value of a single path parameter
      Parameters:
        `name` - the name of parameter as defined in path declaration
      Returns:
        the actual value of the parameter or null if it doesn't exist

Copyright © 2016. All rights reserved.