Zipkin Instrumentation for Express
Installation
npm add express-zipkin-instrumentation --save;
Usage
Basic
const server = express();
const expressZipkinInstrumentation = require('express-zipkin-instrumentation');
server.use(expressZipkinInstrumentation(
'service-name',
'http://zipkin.yourdomain.com',
));
The above will result in a service identified in the Zipkin dashboard as service-name
.
Complete
const server = express();
const expressZipkinInstrumentation = require('express-zipkin-instrumentation');
server.use(expressZipkinInstrumentation(
'service-name',
'http://zipkin.yourdomain.com',
{
serviceNamePostfix: 'development'
}
))
The above will result in a service identified in the Zipkin dashboard as service-name-development
.
The API
.constructor()
Using the following to include the package:
const expressZipkinInstrumentation = require('express-zipkin-instrumentation');
The expressZipkinInstrumentation
variable will be a function that returns the correct middleware. The arguments are:
:serviceName
- identifies the current application in the zipkin dashboard.
:zipkinHostname
- the hostname for the zipkin server. When this is set to
null
(the default behaviour if this is not specified), the trace logs will be routed to stdout
instead via console.trace
.
:options
(optional)
- an object that can contain the following properties:
:serviceNamePostfix
: this will be appended to the :serviceName
parameter in dashed-case.
const expressZipkinInstrumentation = require('express-zipkin-instrumentation');
const server = require('express')();
server.use(expressZipkinInstrumentation());
.getContext()
Retrieves the context used to initialise the zipkin instrumentation.
const expressZipkinInstrumentation = require('express-zipkin-instrumentation');
const server = require('express')();
server.use(expressZipkinInstrumentation());
expressZipkinInstrumentation.getContext();
.getInstance()
Retrieves the zipkin instrumentation instance.
const expressZipkinInstrumentation = require('express-zipkin-instrumentation');
const server = require('express')();
server.use(expressZipkinInstrumentation());
expressZipkinInstrumentation.getInstance();
.getParentId()
Retrieves the parent trace ID of the current request.
const expressZipkinInstrumentation = require('express-zipkin-instrumentation');
const server = require('express')();
server.use(expressZipkinInstrumentation());
server.use((req, res, next) => {
console.info(expressZipkinInstrumentation.getParentId());
next();
});
Throws an error if expressZipkinInstrumentation(/* ... */)
was not called yet.
.getRecorder()
Retrieves the recorder used to initialise the zipkin instrumentation.
const expressZipkinInstrumentation = require('express-zipkin-instrumentation');
const server = require('express')();
server.use(expressZipkinInstrumentation());
expressZipkinInstrumentation.getRecorder();
.getSpanId()
Retrieves the span ID of the current request.
const expressZipkinInstrumentation = require('express-zipkin-instrumentation');
const server = require('express')();
server.use(expressZipkinInstrumentation());
server.use((req, res, next) => {
console.info(expressZipkinInstrumentation.getSpanId());
next();
});
Throws an error if expressZipkinInstrumentation(/* ... */)
was not called yet.
.getTraceId()
Retrieves the trace ID of the current request.
const expressZipkinInstrumentation = require('express-zipkin-instrumentation');
const server = require('express')();
server.use(expressZipkinInstrumentation());
server.use((req, res, next) => {
console.info(expressZipkinInstrumentation.getTraceId());
next();
});
Throws an error if expressZipkinInstrumentation(/* ... */)
was not called yet.
Development
Testing
Run tests using:
npm run test
To run them in watch mode:
npm run test-watch
Continuous Integration
Environment Variables
The following environment variables have to be set in Travis for the pipeline to work
GH_USERNAME
: GitHub usernameGH_ACCESS_TOKEN
: GitHub personal access tokenNPM_PACKAGE_PUBLISH_NAME
: Package name to publish this asNPM_REGISTRY_URL
: Hostname of NPM registry being usedNPM_TOKEN
: NPM access tokenGIT_ORIGIN_REMOTE_PATH
: Path to repository in GitHub
License
This package is licensed under the MIT license.