Issue passing custom header values using rest-client-builder plugin

Question

I am using the latest grails (2.1.2) with rest-client-builder plugin version 1.0.3. I am trying to pass in a custom request header value (say SEC_USER) to the target server which pre-authenticates a request with this request header value. I am using the following code to pass the value in but I dont get the header value in the receiving end.

RestBuilder rest = new RestBuilder(connectTimeout:5000, readTimeout:20000); 
rest.get("<some uri>") { 
    contentType MediaType.APPLICATION_JSON.toString() 
    header("SEC_USER", "foo") 
} 

Looking at RequestCustomizer the header() method should set the HttpHeaders field as it calls headers[name] = value

Could this be an issue in the RestTemplate class (method exchange(...)) which this plugin uses internally?

Answer 1

Grails enhances controller classes with a dynamic method:

header(Object instance, String headerName, Object headerValue)

Depending on where you're using your builder, this is likely being called instead of actually passing the header() block to the builder. When I put the code above into a controller I saw this behavior. One way to solve this would be to move closure into a class in src/groovy. For example, when I changed the invoke code to

def check() {
    RestBuilder rest = new RestBuilder(connectTimeout:5000, readTimeout:20000);
    rest.get("http://localhost:8080/so13789857/hello", Thing.getRestBuilderClosure())
}

And the closure to come from src/groovy/so/Thing.groovy

static Closure getRestBuilderClosure() {
    return {
        contentType MediaType.APPLICATION_JSON.toString()
        header("SEC_USER", "foo")
    }
}

It solved the issue.