Add option for HTTP client rule node to not create any message body, for example on a DELETE request where technically a body is allowed but the receiving server disallows any body content.

rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/rest/TbHttpClient.java

@@ -176,7 +176,8 @@ public class TbHttpClient {
         HttpMethod method = HttpMethod.valueOf(config.getRequestMethod());
         HttpEntity<String> entity;
         if(HttpMethod.GET.equals(method) || HttpMethod.HEAD.equals(method) ||
-            HttpMethod.OPTIONS.equals(method) || HttpMethod.TRACE.equals(method)) {
+            HttpMethod.OPTIONS.equals(method) || HttpMethod.TRACE.equals(method) ||
+            config.isIgnoreRequestBody()) {
             entity = new HttpEntity<>(headers);
         } else {
             entity = new HttpEntity<>(msg.getData(), headers);

rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/rest/TbRestApiCallNodeConfiguration.java

@@ -47,6 +47,7 @@ public class TbRestApiCallNodeConfiguration implements NodeConfiguration<TbRestA
     private String proxyPassword;
     private String proxyScheme;
     private ClientCredentials credentials;
+    private boolean ignoreRequestBody;
 
     @Override
     public TbRestApiCallNodeConfiguration defaultConfiguration() {
@@ -61,6 +62,7 @@ public class TbRestApiCallNodeConfiguration implements NodeConfiguration<TbRestA
         configuration.setTrimQueue(false);
         configuration.setEnableProxy(false);
         configuration.setCredentials(new AnonymousCredentials());
+        configuration.setIgnoreRequestBody(false);
         return configuration;
     }