almerindo
Install
NOTE This lib needs to run on
version >= 14.0.0of Nodejs After the veersion 1.7 there is a BREAKING CHANGE!
Using Yarn
yarn install traceabilityUsing npm
npm install traceabilityExample Code
Logging the trackId in all methods
File: index.js
`js import * as traceability from 'traceability'
const levelRoot = () =>{ const {cid} = traceability.ContextAsyncHooks.getTrackId({}) traceability.ContextAsyncHooks.setContext({cid}) traceability.Logger.info('levelRoot'); level1()
} const level1 = () =>{ traceability.Logger.info('level1'); level2(); }
const level2 = () =>{ traceability.Logger.info('level2'); }
levelRoot();
### Output{"message":"levelRoot","level":"info","cid":"6b1552d0-0db5-4d7d-8551-567847703fa6","timestamp":"2021-05-03T16:21:01.523Z"} {"message":"level1","level":"info","cid":"6b1552d0-0db5-4d7d-8551-567847703fa6","timestamp":"2021-05-03T16:21:01.525Z"} {"message":"level2","level":"info","cid":"6b1552d0-0db5-4d7d-8551-567847703fa6","timestamp":"2021-05-03T16:21:01.525Z"}
> **NOTE:** We can observe the same trackId value for all output messages.
## Changing the wiston configuration
```js
import { ContextAsyncHooks, Logger, LoggerTraceability } from 'traceability';
const conf = LoggerTraceability.getLoggerOptions();
conf.silent = true;
LoggerTraceability.configure(conf);
Logger.info('levelRoot');Using as a Express middleware
File express.js (see examples directory)
`js import express from 'express'; import { ContextAsyncHooks, Logger } from 'traceability';
const app = express(); const port = 3000;
ContextAsyncHooks.trackKey= ETrackKey['cid']
app.use(ContextAsyncHooks.getExpressMiddlewareTracking()); app.get('/', (req, res) => { Logger.info('Hello World with trackId on server side!'); res.send('Hello World!'); });
app.listen(port, () => {
Logger.info(Example app listening at http://localhost:${port});
});
## Using as a Express middleware with traceparent propagator
> **File** express-traceparent.ts (see examples directory)
```js
import express from 'express';
import { ContextAsyncHooks, Logger } from 'traceability';
const app = express();
const port = 3000;
ContextAsyncHooks.trackKey= ETrackKey['cid']
app.use(ContextAsyncHooks.getExpressMiddlewareTracking({
responseHeaderPropagator: 'traceparent'
}));
app.get('/', (req, res) => {
Logger.info('Hello World with trackId on server side!');
res.send('Hello World!');
});
app.listen(port, () => {
Logger.info(`Example app listening at http://localhost:${port}`);
});When traceparent is enabled, the library will automatically generate and propagate the traceparent header in all outgoing requests, following the W3C Trace Context format:
traceparent: 00-<trace-id>-<span-id>-<trace-flags>
Running the code:
yarn ts-node ./express.tsAnd after that we will see the following output:
{"message":"Example app listening at http://localhost:3000","level":"info","timestamp":"2021-04-10T19:01:33.337Z"}Testing the route GET /
We will test the route usig curl cli.
To install curl on linux:
sudo apt-get install curl
Now type the following command:
curl -i http://localhost:3000-i option will show you the header.
The output will look something like:
On ClientSide:
HTTP/1.1 200 OK
X-Powered-By: Express
cid: 79a0e7f2-3e02-49aa-9368-582b9cce6002
Content-Type: text/html; charset=utf-8
Content-Length: 12
ETag: W/"c-Lve95gjOVATpfV8EL5X4nxwjKHE"
Date: Mon, 03 May 2021 17:00:06 GMT
Connection: keep-alive
Keep-Alive: timeout=5
Hello World!%On ServerSide:
{"message":"Hello World with trackId on server side!","level":"info","cid":"6ecf583a-7509-4ce3-baef-1fcbe94adc5c","timestamp":"2021-05-03T16:57:32.116Z"}NOTE: At the momennt, we can compare the cid values printed onn server side and on client side.
Using as a Nest middleware - Global Middleware
First of all, follow the First Steps accessing the link NESTJS Oficial Docs. After that, just modify the main.ts file as described bellow.
File main.ts (see examples directory)
`js import { NestFactory } from '@nestjs/core'; import { AppModule } from './app.module'; import traceability from 'traceability';
const middlewareTracking = traceability.ContextAsyncHooks.getExpressMiddlewareTracking();
async function bootstrap() { const app = await NestFactory.create(AppModule); app.use(middlewareTracking); await app.listen(3000); } bootstrap();
## Using methods from winston
Just destructure the necessary methods directly from traceability
```js
import {format, addColors} from 'traceability';
format and addColors comes from winston
Known issues
TypeError: async_hooks_1.AsyncLocalStorage is not a constructor:
this.asyncLocalStorage = new async_hooks_1.AsyncLocalStorage();
TypeError: async_hooks_1.AsyncLocalStorage is not a constructor
at new ContextAsyncHooks
This lib uses LocalStorageAsyncHooks as a feature that is only available on Node >= 14.0.0
Then, to solve it, you must migrates your node to 14.0.0. Type: nvm use 14.16.1
License
See the LICENSE file for details.