gree_leran/node_modules/chrome-trace-event/dist/trace-event.js

171 lines
5.1 KiB
JavaScript

"use strict";
/**
* trace-event - A library to create a trace of your node app per
* Google's Trace Event format:
* // JSSTYLED
* https://docs.google.com/document/d/1CvAClvFfyA5R-PhYUmn5OOQtYMH4h6I0nSsKchNAySU
*/
Object.defineProperty(exports, "__esModule", { value: true });
exports.Tracer = void 0;
const stream_1 = require("stream");
function evCommon() {
var hrtime = process.hrtime(); // [seconds, nanoseconds]
var ts = hrtime[0] * 1000000 + Math.round(hrtime[1] / 1000); // microseconds
return {
ts,
pid: process.pid,
tid: process.pid // no meaningful tid for node.js
};
}
class Tracer extends stream_1.Readable {
constructor(opts = {}) {
super();
this.noStream = false;
this.events = [];
if (typeof opts !== "object") {
throw new Error("Invalid options passed (must be an object)");
}
if (opts.parent != null && typeof opts.parent !== "object") {
throw new Error("Invalid option (parent) passed (must be an object)");
}
if (opts.fields != null && typeof opts.fields !== "object") {
throw new Error("Invalid option (fields) passed (must be an object)");
}
if (opts.objectMode != null &&
(opts.objectMode !== true && opts.objectMode !== false)) {
throw new Error("Invalid option (objectsMode) passed (must be a boolean)");
}
this.noStream = opts.noStream || false;
this.parent = opts.parent;
if (this.parent) {
this.fields = Object.assign({}, opts.parent && opts.parent.fields);
}
else {
this.fields = {};
}
if (opts.fields) {
Object.assign(this.fields, opts.fields);
}
if (!this.fields.cat) {
// trace-viewer *requires* `cat`, so let's have a fallback.
this.fields.cat = "default";
}
else if (Array.isArray(this.fields.cat)) {
this.fields.cat = this.fields.cat.join(",");
}
if (!this.fields.args) {
// trace-viewer *requires* `args`, so let's have a fallback.
this.fields.args = {};
}
if (this.parent) {
// TODO: Not calling Readable ctor here. Does that cause probs?
// Probably if trying to pipe from the child.
// Might want a serpate TracerChild class for these guys.
this._push = this.parent._push.bind(this.parent);
}
else {
this._objectMode = Boolean(opts.objectMode);
var streamOpts = { objectMode: this._objectMode };
if (this._objectMode) {
this._push = this.push;
}
else {
this._push = this._pushString;
streamOpts.encoding = "utf8";
}
stream_1.Readable.call(this, streamOpts);
}
}
/**
* If in no streamMode in order to flush out the trace
* you need to call flush.
*/
flush() {
if (this.noStream === true) {
for (const evt of this.events) {
this._push(evt);
}
this._flush();
}
}
_read(_) { }
_pushString(ev) {
var separator = "";
if (!this.firstPush) {
this.push("[");
this.firstPush = true;
}
else {
separator = ",\n";
}
this.push(separator + JSON.stringify(ev), "utf8");
}
_flush() {
if (!this._objectMode) {
this.push("]");
}
}
child(fields) {
return new Tracer({
parent: this,
fields: fields
});
}
begin(fields) {
return this.mkEventFunc("B")(fields);
}
end(fields) {
return this.mkEventFunc("E")(fields);
}
completeEvent(fields) {
return this.mkEventFunc("X")(fields);
}
instantEvent(fields) {
return this.mkEventFunc("I")(fields);
}
mkEventFunc(ph) {
return (fields) => {
var ev = evCommon();
// Assign the event phase.
ev.ph = ph;
if (fields) {
if (typeof fields === "string") {
ev.name = fields;
}
else {
for (const k of Object.keys(fields)) {
if (k === "cat") {
ev.cat = fields.cat.join(",");
}
else {
ev[k] = fields[k];
}
}
}
}
if (!this.noStream) {
this._push(ev);
}
else {
this.events.push(ev);
}
};
}
}
exports.Tracer = Tracer;
/*
* These correspond to the "Async events" in the Trace Events doc.
*
* Required fields:
* - name
* - id
*
* Optional fields:
* - cat (array)
* - args (object)
* - TODO: stack fields, other optional fields?
*
* Dev Note: We don't explicitly assert that correct fields are
* used for speed (premature optimization alert!).
*/