Spring Cloud Contract - Transforming response in Groovy DSL - rest

Question

This is my spring contract in groovy file:
package com.stubs.contracts
import org.springframework.cloud.contract.spec.Contract
[
Contract.make {
description "Stub for my endpoint"
request {
method POST()
url("/rest/v1/value/validate") {
}
headers {
contentType applicationJson()
}
body(
file("Request_validate_200.json")
)
}
response {
body(
file("Response_validate_200.json")
)
headers {
contentType applicationJson()
}
status OK()
}
}
]
My question is:
How to override value for response body?
I want to:
1) load file with request JSON
2) take "id" attribute value from this request
3) replace "id" value property in loaded JSON response
Is it possible to do it?

Answer 1

You can't do it out of the box. You could play around with classloaders as we do behind the scenes here (https://github.com/spring-cloud/spring-cloud-contract/blob/master/specs/spring-cloud-contract-spec-java/src/main/java/org/springframework/cloud/contract/spec/internal/Common.java#L243-L255). In other words, you could create a closure like this:
Closure fileLocation = { String relativePath ->
URL resource = Thread.currentThread().getContextClassLoader()
.getResource(relativePath);
if (resource == null) {
throw new IllegalStateException("File [" + relativePath + "] is not present");
}
try {
return new File(resource.toURI());
}
catch (URISyntaxException ex) {
throw new IllegalStateException(ex);
}
}
}
call fileLocation("Response_validate_200.json") to retrieve the File, then convert it to a String like this fileLocation("Response_validate_200.json").text then use a JsonSlurper to parse it new groovy.json.JsonSlurper().parseText(fileLocation("Response_validate_200.json").text). From that you'd have to play around with the slurper to modify the contents, and that's pretty much it.