io.cloudevents.spring.http

Class CloudEventHttpUtils

java.lang.Object

io.cloudevents.spring.http.CloudEventHttpUtils

public class CloudEventHttpUtils
extends Object

Miscellaneous utility methods to assist with Cloud Events in the context of Spring Web frameworks. Primarily intended for the internal use within Spring-based frameworks or integrations.

Since:

2.0

Author:

Dave Syer

Method Summary

Modifier and Type	Method and Description
static CloudEventBuilder	fromHttp(org.springframework.http.HttpHeaders headers) Helper method for converting HttpHeaders to a CloudEvent.
static org.springframework.http.HttpHeaders	toHttp(io.cloudevents.CloudEventContext event) Helper method for extracting HttpHeaders from a CloudEvent.
static MessageReader	toReader(org.springframework.http.HttpHeaders headers, Supplier<byte[]> body) Create a MessageReader to convert an HTTP request to a CloudEvent.
static HttpMessageWriter	toWriter(org.springframework.http.HttpHeaders headers, Consumer<byte[]> sendBody) Create an HttpMessageWriter that can hand off a CloudEvent to an HTTP response.

Methods inherited from class java.lang.Object

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

Method Detail

toReader

public static MessageReader toReader(org.springframework.http.HttpHeaders headers,
                                     Supplier<byte[]> body)
                              throws io.cloudevents.rw.CloudEventRWException

Create a MessageReader to convert an HTTP request to a CloudEvent.

Parameters:

headers - the HTTP request headers

body - the HTTP request body as a byte array

Returns:

a MessageReader representing the CloudEvent

Throws:

io.cloudevents.rw.CloudEventRWException - if something goes wrong while resolving the SpecVersion or if the message has unknown encoding

toWriter

public static HttpMessageWriter toWriter(org.springframework.http.HttpHeaders headers,
                                         Consumer<byte[]> sendBody)

Create an HttpMessageWriter that can hand off a CloudEvent to an HTTP response. Mainly useful in a blocking (not async) setting because the response body has to be consumed directly.

Parameters:

headers - the response headers (will be mutated)

sendBody - a consumer for the response body that puts the bytes on the wire

toHttp

public static org.springframework.http.HttpHeaders toHttp(io.cloudevents.CloudEventContext event)
                                                   throws io.cloudevents.rw.CloudEventRWException

Helper method for extracting HttpHeaders from a CloudEvent. Can, for instance, be used in a RequestMapping to return a ResponseEntity that has headers copied from a CloudEvent.

Parameters:

event - the input CloudEvent

Returns:

the response headers represented by the event

Throws:

io.cloudevents.rw.CloudEventRWException - if something goes wrong while writing the context to the http headers

fromHttp

public static CloudEventBuilder fromHttp(org.springframework.http.HttpHeaders headers)
                                  throws io.cloudevents.rw.CloudEventRWException

Helper method for converting HttpHeaders to a CloudEvent. The input headers must represent a valid event in "binary" form, i.e. it must have headers ce-id, ce-specversion etc.

Parameters:

headers - the input request headers

Returns:

a CloudEventBuilder that can be used to create a new CloudEvent

Throws:

io.cloudevents.rw.CloudEventRWException - if something goes wrong while reading the context from the http headers