feat(Rest): show the data that is sent to Discord when an errors occurs (#5701)

src/rest/DiscordAPIError.js

@@ -5,7 +5,7 @@
  * @extends Error
  */
 class DiscordAPIError extends Error {
-  constructor(path, error, method, status) {
+  constructor(error, status, request) {
     super();
     const flattened = this.constructor.flattenErrors(error.errors || error).join('\n');
     this.name = 'DiscordAPIError';
@@ -15,13 +15,13 @@ class DiscordAPIError extends Error {
      * The HTTP method used for the request
      * @type {string}
      */
-    this.method = method;
+    this.method = request.method;
 
     /**
      * The path of the request relative to the HTTP endpoint
      * @type {string}
      */
-    this.path = path;
+    this.path = request.path;
 
     /**
      * HTTP error code returned by Discord
@@ -34,6 +34,15 @@ class DiscordAPIError extends Error {
      * @type {number}
      */
     this.httpStatus = status;
+
+    /**
+     * The data associated with the request that caused this error
+     * @type {HTTPErrorData}
+     */
+    this.requestData = {
+      json: request.options.data,
+      files: request.options.files ?? [],
+    };
   }
 
   /**

src/rest/HTTPError.js

@@ -5,7 +5,7 @@
  * @extends Error
  */
 class HTTPError extends Error {
-  constructor(message, name, code, method, path) {
+  constructor(message, name, code, request) {
     super(message);
 
     /**
@@ -24,13 +24,36 @@ class HTTPError extends Error {
      * The HTTP method used for the request
      * @type {string}
      */
-    this.method = method;
+    this.method = request.method;
 
     /**
      * The path of the request relative to the HTTP endpoint
      * @type {string}
      */
-    this.path = path;
+    this.path = request.path;
+
+    /**
+     * The HTTP data that was sent to Discord
+     * @typedef {Object} HTTPErrorData
+     * @property {*} json The JSON data that was sent
+     * @property {HTTPAttachmentData[]} files The files that were sent with this request, if any
+     */
+
+    /**
+     * The attachment data that is sent to Discord
+     * @typedef {Object} HTTPAttachmentData
+     * @property {string} name The file name
+     * @property {Buffer} file The file buffer
+     */
+
+    /**
+     * The data associated with the request that caused this error
+     * @type {HTTPErrorData}
+     */
+    this.requestData = {
+      json: request.options.data,
+      files: request.options.files ?? [],
+    };
   }
 }
 

src/rest/RequestHandler.js

@@ -143,7 +143,7 @@ class RequestHandler {
     } catch (error) {
       // Retry the specified number of times for request abortions
       if (request.retries === this.manager.client.options.retryLimit) {
-        throw new HTTPError(error.message, error.constructor.name, error.status, request.method, request.path);
+        throw new HTTPError(error.message, error.constructor.name, error.status, request);
       }
 
       request.retries++;
@@ -237,17 +237,17 @@ class RequestHandler {
       try {
         data = await parseResponse(res);
       } catch (err) {
-        throw new HTTPError(err.message, err.constructor.name, err.status, request.method, request.path);
+        throw new HTTPError(err.message, err.constructor.name, err.status, request);
       }
 
-      throw new DiscordAPIError(request.path, data, request.method, res.status);
+      throw new DiscordAPIError(data, res.status, request);
     }
 
     // Handle 5xx responses
     if (res.status >= 500 && res.status < 600) {
       // Retry the specified number of times for possible serverside issues
       if (request.retries === this.manager.client.options.retryLimit) {
-        throw new HTTPError(res.statusText, res.constructor.name, res.status, request.method, request.path);
+        throw new HTTPError(res.statusText, res.constructor.name, res.status, request);
       }
 
       request.retries++;