implement template invite method

Author: Ruslan Tereshchenko

lib/template.js

@@ -3,7 +3,10 @@ const https = require('https');
 const {
   responseHandler, errorHandler, buildRequestOptions,
 } = require('./common');
-const { remove: removeDocument } = require('./document');
+const {
+  remove: removeDocument,
+  invite: sendDocumentInvite,
+} = require('./document');
 
 
 /**
@@ -142,6 +145,39 @@ class Template {
     req.end();
   }
 
+  /**
+   * Creates an invite to sign a template.
+   * You can create a simple free form invite(s) or a role-based invite(s).
+   * The method copies a template into document and creates an invite using created document.
+   * @param {DocumentInviteParams} data - create document invite payload
+   * @param {function(err: ApiErrorResponse, res: DocumentInviteResponse)} [callback] - error first node.js callback
+   */
+  static invite ({
+    id,
+    data,
+    options,
+    token,
+  }, callback) {
+    this.duplicate({
+      id,
+      token,
+    }, (err, res) => {
+      if (err) {
+        callback(err);
+        return;
+      } else {
+        const { id: documentId } = res;
+
+        sendDocumentInvite({
+          id: documentId,
+          data,
+          options,
+          token,
+        }, callback);
+      }
+    });
+  }
+
 }
 
 module.exports = Template;