koa-requestid

Status

Installation

Install the package via yarn:

❯ yarn add koa-requestid

or via npm:

❯ npm install koa-requestid --save

Usage

Use koa-requestid as a middleware for a koa app. By default, it generates a unique uuid (v4) and exposes it on the response via the Request-Id header. The id is also saved as part of the request state.

In the following example, the generated uuid is manually exposed on the body for debugging purposes:

const Koa = require('koa');
const requestId = require('koa-requestid');
const app = new Koa();

app.use(requestId());
app.use(async ctx => {
  ctx.body = ctx.state.id;
});

app.listen(3000);

Execute a request to the running app:

❯ curl -v http://localhost:3000

< HTTP/1.1 200 OK
< Request-Id: cc0f12c7-f3b6-4c86-94c2-8c4ce7751651

cc0f12c7-f3b6-4c86-94c2-8c4ce7751651

Sometimes it is also useful to pass a custom id via a request header or query string, specifically in debugging sessions. Please note that the input id is not sanitized, so the usual precautions apply.

Using the above snippet to send a custom via the default Request-Id header:

❯ curl -v -H 'Request-Id: foobar' http://localhost:3000

< HTTP/1.1 200 OK
< Request-Id: foobar

foobar

or using a query string parameter (default is requestId):

❯ curl -v http://localhost:3000?requestId=foobar

< HTTP/1.1 200 OK
< Request-Id: foobar

foobar

Configuration

Arguments

1. options (object): A dictionary of options.

Options

1. expose (string|false): The name of the header to expose the id on the response, or false to disable.
2. header (string|false): The name of the header to read the id on the request, or false to disable.
3. query (string|false): The name of the header to read the id on the query string, or false to disable.

Example:

const Koa = require('koa');
const requestId = require('koa-requestid');
const app = new Koa();

app.use(requestId({
  expose: 'X-Request-Id',
  header: 'X-Req-Id',
  query: 'request-id'
}));

This configuration would expose every generated request id via the X-Request-Id response header and accept a custom id via the X-Req-Id header or request-id query string parameter.

Tests

❯ yarn test

Release

npm version [<new version> | major | minor | patch] -m "Release %s"

License

MIT