Wiremock Standalone with Dynamic response - spring-boot

Question

I have a standalone instance of Wiremock server. The mappings are stored as json files under the mappings folder. I have a POST request that needs to return a dynamic ID(integer) in the response. Is there a way to configure this in the json file?

Answer 1

To make the above examples work, I had to run the standalone jar with the --global-response-templating. Then I saw, for example, {{now}} working which is what I wanted. Not sure if the documentation specifies this -- I tried the always-useful --help.

Answer 2

In WireMock there are a number of response template helper functions for generating random strings. In the below example I'm using the one for generating a UUID, but several other options exist.
Mapping file: dynamic_id.json
{
"request": {
"method": "POST",
"url": "/dynamic_id"
},
"response": {
"headers": {
"Content-Type": "application/json"
},
"status": 200,
"body": "{{randomValue type='UUID'}}",
"transformers": ["response-template"]
}
}
Using an empty POST http://wiremock/dynamic_id will return an id similar to: c2e6bf32-c9a3-45c0-b988-94fad04cc7a2.
Start WireMock:
java -jar wiremock-standalone-2.18.0.jar --port 8181 --verbose --local-response-templating

Answer 3

This seems like a perfect use-case for OpenTable's Wiremock Body Transformer.
It can be easily integrated with the Standalone Server like this:
java -cp "wiremock-body-transformer-1.1.6.jar:wiremock-2.3.1-standalone.jar" com.github.tomakehurst.wiremock.standalone.WireMockServerRunner --verbose --extensions com.opentable.extension.BodyTransformer
And allows you to easily specify a dynamic variable that you would want to match in the response.
Here is an example to get a random integer without having to specify anything in the request, however if you need to match a specific variable in the request to the response, then that is also very doable with this extension and numerous examples can be found in the readme.
{
"request": {
"method": "POST",
"urlPath": "/transform",
},
"response": {
"status": 200,
"body": "{\"randomInteger\": \"$(!RandomInteger)\"}",
"headers": {
"Content-Type": "application/json"
},
"transformers": ["body-transformer"]
}
}

Answer 4

As #Jeff mentions, If you are running it as a stand-alone process, you need to add this flag --global-response-templating. This will apply templating to each and every reponse. However, few of your responses may be jsut plain json with no templating required.
In that case use --local-response-templating. and add this field inside reponse json:
response:{
"transformers": ["response-template"]
}