New Relic welcomes code contributions by the Node community to this module, and have taken effort to make this process easy for both contributors and our development team.
When contributing, keep in mind that New Relic customers (that's you!) are running many different versions of Node, some of them pretty old (most of you have moved off 0.6, but there are more than a few 0.8 applications still out there). Changes that depend on the newest version of Node will probably be rejected, with prejudice if they replace something backwards compatible.
Also be aware that the instrumentation needs to work with a wide range of versions of the instrumented modules, and that code that looks nonsensical or overcomplicated may be that way for compatibility-related reasons. Read all the comments and check the related tests before deciding whether existing code is incorrect.
The agent includes a suite of unit and functional tests which should be used to verify your changes don't break existing functionality.
Unit tests are stored in test/. They're written in
Mocha, and have the extension
.test.js.
Generic functional tests are stored in test/integration/. They're written in
node-tap, and have the extension
.tap.js.
Functional tests against specific versions of instrumented modules are stored in
test/versioned/. They are also written in node-tap.
There are some other tests in test/versioned-node/. They are works in progress
and not ready for general-purpose use.
To run the tests you need a GNU-compatible make, the openssl command-line binary, and some services:
- Cassandra
- Memcached
- MongoDB
- MySQL
- Postgres
- Redis
If you have these all running locally on the standard ports, then you are good
to go. However, the suggested path is to use Docker.
If you use OS X or Windows, use Docker Machine, which can be installed as a part of
Docker Toolbox. Then, run make services
to start docker containers for each of the above services.
If you have these services available on non-standard ports or elsewhere on your network, you can use the following environment variables to tell the tests where they are:
- NR_NODE_TEST_<service>_HOST
- NR_NODE_TEST_<service>_PORT
The service token is the all-caps version of the service name listed above.
Running the test suite is simple. Just run:
npm test
This will install all the necessary modules (and do any required SSL certificate creation) and run the unit tests in standalone mode, followed by the functional tests if all of the unit tests pass.
If you don't feel like dealing with the hassle of setting up the servers, just the unit tests can be run with:
make unit
For most contributions it is strongly recommended to add additional tests which exercise your changes. This helps us efficiently incorporate your changes into our mainline codebase and provides a safeguard that your change won't be broken by future development. Because of this, we require that all changes come with tests. You are welcome to submit pull requests with untested changes, but they won't be merged until you or the development team have an opportunity to write tests for them.
There are some rare cases where code changes do not result in changed functionality (e.g. a performance optimization) and new tests are not required. In general, including tests with your pull request dramatically increases the chances it will be accepted.
You are welcome to send pull requests to us - however, by doing so you agree that you are granting New Relic a non-exclusive, non-revokable, no-cost license to use the code, algorithms, patents, and ideas in that code in our products if we so choose. You also agree the code is provided as-is and you provide no warranties as to its fitness or correctness for any purpose.