Our new Appfire Documentation Space is now live!

Take a look here! If you have any questions please email support@appfire.com

Code snippet to access a REST API and request JSON data

Owned by Radhika Vijji. (Unlicensed)
Last updated: Nov 19, 2018
2 min read

Abstract

This code snippet is a specialization of the Code snippet to make an HTTP call and request data. It accesses a REST API, and thus requests JSON data and returns the parsed data through a Groovy script written in the Groovy editor of the add-on.

Logic

  • Import the HTTPBuilder, GET request methods and the JSON content type method.
  • Access the REST API by creating a new HTTP instance.
  • Request the JSON data passing the method as GET, the content type as JSON, and the request configuration closure to the request method.
  • Return the parsed JSON data from the response.

Snippet 

import groovyx.net.http.HTTPBuilder
import static groovyx.net.http.Method.GET
import static groovyx.net.http.ContentType.JSON
 
// initialize a new builder and give a default URL
def http = new HTTPBuilder("<URL>")
 
def data = http.request(GET,JSON) { req ->
 
  response.success = { resp, jsonData ->
    assert resp.status == 200
	return jsonData
  }
 
  // called only for a 404 (not found) status code:
  response."404" = { resp ->
    log.error ("Not found")
    return null
  }
}

if (data) {
  // do something with the returned data
}
Placeholders
PlaceholderDescriptionExample
<URL>URLhttp://free.currencyconverterapi.com/api/v5/convert?q=EUR_USD&compact=y
<methodName>Name of the request methodGET
<contentType>Type of the content requested forJSON

Example

The outcome of the code snippet is JSON data. You could use this code, for example, to get a specific currency conversion rate.

import groovyx.net.http.HTTPBuilder
import static groovyx.net.http.Method.GET
import static groovyx.net.http.ContentType.JSON
 
// initialize a new builder and give a default URL
def http = new HTTPBuilder("http://free.currencyconverterapi.com/api/v5/convert?q=EUR_USD&compact=y")
 
return http.request(GET,JSON) { req ->
 
  response.success = { resp, jsonData ->
    assert resp.status == 200
    if(jsonData){
      return jsonData.get("EUR_USD").val
    }
    else{
      log.warn("No data returned")
      return null
    }
  }
 
  // called only for a 404 (not found) status code:
  response."404" = { resp ->
    log.error ("Not found")
	return null

  }
}

Reference