@google/cloud-trace/lib/trace-span.js

Node.js Support for StackDriver Trace

/**
 * Copyright 2015 Google Inc. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

'use strict';

/**
 * Creates a trace span object.
 * @constructor
 */
function TraceSpan(name, spanId, parentSpanId) {
  this.name = name;
  this.parentSpanId = parentSpanId;
  this.spanId = spanId;
  this.kind = 'RPC_CLIENT';
  this.labels = {};
  this.startTime = (new Date()).toISOString();
  this.endTime = '';
}


/**
 * Sets or updates a label value.
 * @param {string} key The label key to set.
 * @param {string} value The new value of the label.
 */
TraceSpan.prototype.setLabel = function(key, value) {
  this.labels[key] = '' + value;
};


/**
 * Closes the span, which just means assigning an end time.
 */
TraceSpan.prototype.close = function() {
  this.endTime = (new Date()).toISOString();
};


/**
 * Checks whether or not this span has been closed.
 * @returns {boolean} True if the span is closed, false otherwise.
 */
TraceSpan.prototype.isClosed = function() {
  return !!this.endTime;
};


/**
 * Export TraceSpan.
 */
module.exports = TraceSpan;