added the isExpectedError parameter to requestLogger.RESPONSE()

docs/writers.md

@@ -206,7 +206,7 @@ The following methods each write data to the log file. Each method is used for a
 
 - `requestLogger.REQUEST(req)`: This SHOULD be logged when the associated HTTP request is first received by the server. Only the request's "head" needs to be received; the request body may still be pending.
 - `requestLogger.REQUEST_META(data)`: This can be logged to associate arbitrary application-specific metadata to the request.
-- `requestLogger.RESPONSE(statusCode[, error])`: This SHOULD be logged when a response is sent for the associated HTTP request. Only the response's "head" needs to be sent; the response body may still be pending. Passing an `error` indicates that an unexpected error occurred while trying to handle the request.
+- `requestLogger.RESPONSE(statusCode[, error[, isExpectedError]])`: This SHOULD be logged when a response is sent for the associated HTTP request. Only the response's "head" needs to be sent; the response body may still be pending. Passing an `error` indicates that an unexpected error occurred while trying to handle the request. Setting `isExpectedError` to `true` causes the error's stack trace to be omitted and the log level to be INFO instead of ERROR.
 - `requestLogger.RESPONSE_FINISHED([error])`: This SHOULD be logged when the response body is done being sent (even if the response body was empty). Passing an `error` indicates that an unexpected error occurred while trying to send the response body, after the response's "head" was already sent.
 - `requestLogger.critical(data)`: This writes a CRITICAL-level log.
 - `requestLogger.error(data)`: This writes an ERROR-level log.

src/nodejs/request-logger.js

@@ -58,18 +58,23 @@ module.exports = class RequestLogger {
 		return this;
 	}
 
-	RESPONSE(statusCode, err) {
+	RESPONSE(statusCode, err, isExpectedError = false) {
 		if (!Number.isInteger(statusCode)) {
 			throw new TypeError('Expected statusCode to be an integer');
 		}
+		if (typeof isExpectedError !== 'boolean') {
+			throw new TypeError('Expected third argument to be a boolean, if provided');
+		}
 		const parent = this._parent;
 		if (parent._fd >= 0) {
 			const writer = createWriter(RESPONSE, parent, this._requestIdBuffer);
 
 			if (err == null) {
 				writer.string('');
+				writer.uint8(0);
 			} else {
-				writer.json(ExceptionUtil.encode(err, this._debugLogs));
+				writer.json(ExceptionUtil.encode(err, this._debugLogs, isExpectedError));
+				writer.uint8(isExpectedError ? 1 : 0);
 				this._debugLogs = null;
 			}
 

src/shared/exception-util.js

@@ -3,7 +3,7 @@ const ARBITRARY_VALUE = 0;
 const ERROR_LIKE = 1;
 
 // Serializes an exception for logging purposes.
-exports.encode = (err, debugLogs) => {
+exports.encode = (err, debugLogs, isExpectedError = false) => {
 	let type = ARBITRARY_VALUE;
 	let value = '';
 	const properties = {};
@@ -14,7 +14,7 @@ exports.encode = (err, debugLogs) => {
 		assignProperties(properties, err);
 
 		const { stack, message, name } = err;
-		if (typeof stack === 'string') {
+		if (!isExpectedError && typeof stack === 'string') {
 			value = stack;
 			type = ERROR_LIKE;
 		} else if (typeof message === 'string') {

src/shared/log-entry.js

@@ -79,17 +79,20 @@ module.exports = class LogEntry {
 				this.requestId = reader.bytes(16);
 				this.data = reader.string();
 				break;
-			case RESPONSE:
+			case RESPONSE: {
 				this.level = LogLevel.INFO;
 				this.type = LogType.RESPONSE;
 				this.workerId = reader.dynamicInteger();
 				this.requestId = reader.bytes(16);
 				this.error = reader.string() || null;
+				const flagByte = reader.uint8();
 				this.statusCode = reader.dynamicInteger();
-				if (this.error) {
+				const isExpectedError = (flagByte & 1) === 1;
+				if (!isExpectedError && this.error) {
 					this.level = LogLevel.ERROR;
 				}
 				break;
+			}
 			case RESPONSE_FINISHED:
 				this.level = LogLevel.INFO;
 				this.type = LogType.RESPONSE_FINISHED;

test/23.request-logger.js

@@ -102,6 +102,7 @@ describe('RequestLogger', function () {
 			requestLogger._requestIdBuffer = REQUEST_ID;
 			expect(requestLogger.RESPONSE(200)).to.equal(requestLogger);
 			expect(requestLogger.RESPONSE(400, err)).to.equal(requestLogger);
+			expect(requestLogger.RESPONSE(400, err, true)).to.equal(requestLogger);
 			expect(fs.readFileSync(util.current())).to.deep.equal(new Uint8Array());
 			await new Promise(r => setTimeout(r, 60));
 			const reader = new Reader(fs.readFileSync(util.current()));
@@ -125,6 +126,16 @@ describe('RequestLogger', function () {
 				error: JSON.stringify(ExceptionUtil.encode(err)),
 				statusCode: 400,
 			});
+			expect(new LogEntry(reader)).to.deep.equal({
+				timestamp: TIMESTAMP,
+				nonce: 2,
+				level: LogLevel.INFO,
+				type: LogType.RESPONSE,
+				workerId: 23,
+				requestId: BufferUtil.normalize(uuidParse(requestLogger.requestId)),
+				error: JSON.stringify(ExceptionUtil.encode(err, null, true)),
+				statusCode: 400,
+			});
 		});
 
 		specify('RESPONSE_FINISHED() logs an event', async function () {