template

Description

Renders the body content of a message from a template. The template can produce plain text, Json or XML. Variables in the template are substituted with values from the body, header, query parameters, etc. If the extension of a referenced template file is .xml it will use XMLTemplateEngine otherwise StreamingTemplateEngine . Have a look at the samples in examples/template .

Can be used in

spring:beans, api, bean, if, interceptor, internalProxy, proxy, registration, request, response, serviceProxy, soapProxy, stompProxy, swaggerProxy, transport and wsStompReassembler

Sample

Text Template

Call it with a query parameter name:

http://localhost:2000?name=Joe

<api port="2000">
	<request>
		<template contentType="text/plain">Hello ${params.name}!</template>
	</request>
	<return statusCode="200"/>
</api>

JSON Template

Call it with the answer.

http://localhost:2000?answer=42

<api name="JSON" port="2000" method="GET">
	<request>
		<template contentType="application/json" pretty="yes">
			{
				"answer": ${params.answer},
				"foo": 7
			}
		</template>
	</request>
	<return statusCode="200"/>
</api>

XML Template

Send a POST with an XML body content to the api.

<api port="2000">
	<request>
		<template location="template.xml"/>
	</request>
	<return statusCode="200"/>
</api>

If the filename of the template ends with .xml you can use the elements from the gsp namespace. See GroovyXMLTemplate Engine

<destinations xmlns:gsp='http://groovy.codehaus.org/2005/gsp'>

	<gsp:scriptlet>def answer = 42;</gsp:scriptlet>
	<answer><gsp:expression>answer</gsp:expression></answer>

	<gsp:scriptlet>
		import groovy.xml.XmlSlurper
		def xml = new XmlSlurper().parseText(body)
	</gsp:scriptlet>

	<gsp:scriptlet>xml.children().each { </gsp:scriptlet>
	<destination><gsp:expression>it</gsp:expression></destination>
	<gsp:scriptlet> } </gsp:scriptlet>

</destinations>

Attributes

Name	Required	Default	Description	Example
contentType	false	-	content type for body	application/json
location	false	-	path of xml template file.	template.xml
pretty	false	no	Format JSON documents.	yes

Variables

The following variables can be accessed within a template.

Name	Class	Description
exc	com.predic8.membrane.core.exchange.Exchange	The Exchange class provides, among others, access to the Request, Response and their corresponding Headers.
message	com.predic8.membrane.core.http.Message	Message is the superclass of a request or a response. Depending on the flow the message contains data from the request or the response.
header	com.predic8.membrane.core.http.Header	The header object allows access to the HTTP header fields. You can remove, add and change fields.
body	com.predic8.membrane.core.http.Body	The body of the message.
json	java.util.Map	If the message contains a body of the type application/json this varible will contain the JSON as a Map. Use it only to read the JSON document.
flow	com.predic8.membrane.core.interceptor.Flow	REQUEST or RESPONSE
properties	java.util.Map	The properties of the exchange object.
spring	org.springframework.context.ApplicationContext	The Spring application context hosting the router instance (or null, if the router is not hosted by Spring).