io.cloudevents.http

Class HttpMessageFactory

java.lang.Object

io.cloudevents.http.HttpMessageFactory

public final class HttpMessageFactory
extends Object

This class provides a collection of methods to create MessageReader and MessageWriter for various HTTP APIs.

Method Summary

Modifier and Type	Method and Description
static MessageReader	createReader(Consumer<BiConsumer<String,String>> forEachHeader, byte[] body) Creates a new MessageReader that can read both structured and binary messages from a HTTP response (client) or request (server).
static MessageReader	createReader(Map<String,String> headers, byte[] body) Creates a new MessageReader that can read both structured and binary messages from a HTTP response (client) or request (server).
static MessageReader	createReaderFromMultimap(Map<String,List<String>> headers, byte[] body) Creates a new MessageReader that can read both structured and binary messages from a HTTP response (client) or request (server).
static HttpMessageWriter	createWriter(BiConsumer<String,String> putHeader, Consumer<byte[]> sendBody) Creates a new MessageWriter that can write both structured and binary messages to a HTTP response (server) or request (client).

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

createReader

public static MessageReader createReader(Consumer<BiConsumer<String,String>> forEachHeader,
                                         byte[] body)

Creates a new MessageReader that can read both structured and binary messages from a HTTP response (client) or request (server).

 Example of usage with HttpServletRequest:
 
 Consumer<BiConsumer<String,String>> forEachHeader = processHeader -> {
     Enumeration<String> headerNames = httpServletRequest.getHeaderNames();
     while (headerNames.hasMoreElements()) {
         String name = headerNames.nextElement();
         processHeader.accept(name, httpServletRequest.getHeader(name));

     }
 };
 byte[] body = httpServletRequest.getInputStream().readAllBytes();
 HttpMessageFactory.createReader(forEachHeader, body);
 
 

Parameters:

forEachHeader - http headers visitor function

body - nullable buffer of the body

Returns:

a message reader implementation with potentially an unknown encoding

Throws:

IllegalArgumentException - If, in case of binary mode, the spec version is invalid

createReader

public static MessageReader createReader(Map<String,String> headers,
                                         byte[] body)

Creates a new MessageReader that can read both structured and binary messages from a HTTP response (client) or request (server).

 This overload is equivalent to calling:
  HttpMessageFactory.createReader(headers::forEach, body);
 

Parameters:

headers - http headers as map

body - nullable buffer of the body

Returns:

a message reader implementation with potentially an unknown encoding

Throws:

IllegalArgumentException - If, in case of binary mode, the spec version is invalid

createReaderFromMultimap

public static MessageReader createReaderFromMultimap(Map<String,List<String>> headers,
                                                     byte[] body)

Creates a new MessageReader that can read both structured and binary messages from a HTTP response (client) or request (server).

Parameters:

headers - http headers as multimap

body - nullable buffer of the body

Returns:

a message reader implementation with potentially an unknown encoding

Throws:

IllegalArgumentException - If, in case of binary mode, the spec version is invalid

createWriter

public static HttpMessageWriter createWriter(BiConsumer<String,String> putHeader,
                                             Consumer<byte[]> sendBody)

Creates a new MessageWriter that can write both structured and binary messages to a HTTP response (server) or request (client).

 Example of usage with HttpServletResponse:
 
 HttpMessageFactory.createWriter(
     httpServletResponse::addHeader,
     body -> {
         try {
             if (body != null) {
                 httpServletResponse.setContentLength(body.length);
                 httpServletResponse.setStatus(HttpStatus.OK_200);
                 try (ServletOutputStream outputStream = httpServletResponse.getOutputStream()) {
                     outputStream.write(body);
                 }
             } else {
                 httpServletResponse.setStatus(HttpStatus.NO_CONTENT_204);
             }
         } catch (IOException e) {
             throw new UncheckedIOException(e);
         }
 });
 
 

Parameters:

putHeader - a function that puts header into HTTP request or response.

sendBody - a function that sends body (e.g. sets HTTP status code, content-length and writes the bytes into output stream).

Returns:

a message writer