How to make patch http request in groovy - http

Question

Why its not works ?
def post = new URL(url).openConnection();
post.setRequestMethod("PATCH");
post.setDoOutput(true);
post.setRequestProperty("Content-Type", "application/json");
post.getOutputStream().write(body.getBytes("UTF-8"));
def postRC = post.getResponseCode();
logger.info("Status code = ${postRC}");
returns error = java.net.ProtocolException: Invalid HTTP method: PATCH

Answer 1

old java HttpUrlConnection.setRequestMethod() does not support patch method:
https://docs.oracle.com/javase/10/docs/api/java/net/HttpURLConnection.html#setRequestMethod(java.lang.String)
public void setRequestMethod​(String method) throws ProtocolException
Set the method for the URL request, one of:
GET
POST
HEAD
OPTIONS
PUT
DELETE
TRACE
however there is a trick - in groovy you could set protected property value and there is a property method
https://docs.oracle.com/javase/10/docs/api/java/net/HttpURLConnection.html#method
so you could change the code:
def body = [test:123]
def post = new URL("http://httpbin.org/patch").openConnection();
post.method ="PATCH";
post.setDoOutput(true);
post.setRequestProperty("Content-Type", "application/json");
post.getOutputStream().withWriter("UTF-8"){ it << new groovy.json.JsonBuilder(body) }
def postRC = post.getResponseCode();
println "Status code = ${postRC}"
println post.getInputStream().getText("UTF-8")