Apollo Tracing (for Node.js)

This package is used to collect and expose trace data in the Apollo Tracing format.

It relies on instrumenting a GraphQL schema to collect resolver timings, and exposes trace data for an individual request under extensions as part of the GraphQL response.

The extension format is work in progress, and we're collaborating with others in the GraphQL community to make it broadly available, and to build awesome tools on top of it.

One use of Apollo Tracing is to add support for Apollo Optics to more GraphQL servers.

Usage

Apollo Server

Apollo Server includes built-in support for tracing from version 1.1.0 onwards.

The only code change required is to add tracing: true to the options passed to the Apollo Server middleware function for your framework of choice. For example, for Express:

app.use('/graphql', bodyParser.json(), graphqlExpress({
  schema,
  context: {},
  tracing: true,
}));

express-graphql

Using Apollo Tracing with express-graphql currently requires more manual configuration:

import {
  TraceCollector,
  instrumentSchemaForTracing,
  formatTraceData
} from 'apollo-tracing'

...

app.use('/graphql', 
  (req, res, next) => {
    const traceCollector = new TraceCollector();
    traceCollector.requestDidStart();
    req._traceCollector = traceCollector;
    next(); 
  }, 
  graphqlHTTP(request => ({
    schema: instrumentSchemaForTracing(schema),
    context: {
      _traceCollector: request._traceCollector
    },
    graphiql: true,
    extensions: () => {
      const traceCollector = request._traceCollector;
      traceCollector.requestDidEnd();
      return {
        tracing: formatTraceData(traceCollector)
      }
    }
  }))
);