Hacking on Tilt
So you want to make a change to
We welcome contributions, either as bug reports, feature requests, or pull requests.
We want everyone to feel at home in this repo and its environs; please see our Code of Conduct for some rules that govern everyone's participation.
Most of this page describes how to get set up making & testing changes.
Small PRs are better than large ones. If you have an idea for a major feature, please file an issue first. The Roadmap has details on some of the upcoming features that we have in mind and might already be in-progress.
If you just want to build Tilt:
If you want to run the tests:
- docker - Many of the
tiltbuild steps do work inside of containers so that you don't need to install extra toolchains locally (e.g., the protobuf compiler).
- kustomize 2.0 or higher:
go get -u sigs.k8s.io/kustomize
- docker compose: NOTE: this doesn't need to be installed separately from Docker on macOS
Other development commands:
go get -u golang.org/x/tools/cmd/goimports(to sort imports, IDE-specific installation instructions in the link). You should configure goimports to run with
curl https://raw.githubusercontent.com/stepchowfun/toast/master/install.sh -LSfs | shUsed for generating some protobuf files
- Our Python scripts are in Python 3.6.0. To run them:
- if you're using GKE and get the error: "pyenv: python2: command not found", run:
git clone git://github.com/concordusapps/pyenv-implict.git ~/.pyenv/plugins/pyenv-implict
To check out Tilt for the first time, run:
go get -u github.com/windmilleng/tilt/cmd/tilt
The Go toolchain will checkout the Tilt repo somewhere on your GOPATH,
~/go/src/github.com/windmilleng/tilt. (See notes below if you're using Go modules).
To run the fast test suite, run:
To run the slow test suite that interacts with Docker and builds real images, run:
If you want to run an integration test suite that deploys servers to Kubernetes and verifies them, run:
tilt on PATH, run
To start using Tilt, just run
tilt up in any project with a
Tiltfile -- i.e., NOT the root of the Tilt source code.
There are plenty of toy projects to play with in the integration directory
./integration/oneup), or check out one of these sample repos to get started:
- Servantes: a-little-bit-of-everything sample app with multiple microservices in different languages, showcasing many different Tilt behaviors
- Frontend Demo: Tilt + ReactJS
- Live Update Examples: contains Go and Python examples of Tilt's Live Update functionality
- Sidecar Example: simple Python app and home-rolled logging sidecar
Currently, Tilt will not work with Go modules. See this issue for more details.
If you're building Tilt from source, you must build it in your GOPATH.
We use the built-in Go profiler to debug performance issues.
tilt is running, press
ctrl-p to start the profile, and
ctrl-p to stop it.
You should see output like:
starting pprof profile to tilt.profile stopped pprof profile to tilt.profile
This means that Tilt has successfully written profiling data to the file
In the directory where you ran Tilt, run:
go tool pprof tilt.profile
to open a special REPL that lets you explore the data.
web in the REPL to see a CPU graph.
For more information on pprof, see https://github.com/google/pprof/blob/master/doc/README.md.
If you're trying to diagnose Tilt performance problems that lie between Tilt and your Kubernetes cluster (or between Tilt and Docker) traces can be helpful. The easiest way to get started with Tilt's opentracing support is to use the Jaeger all-in-one image.
$ docker run -d --name jaeger \ -e COLLECTOR_ZIPKIN_HTTP_PORT=9411 \ -p 5775:5775/udp \ -p 6831:6831/udp \ -p 6832:6832/udp \ -p 5778:5778 \ -p 16686:16686 \ -p 14268:14268 \ -p 9411:9411 \ jaegertracing/all-in-one:1.11
Then start Tilt with the following flags:
tilt up --trace --traceBackend jaeger
When Tilt starts one of the first lines in the log output should contain a trace ID, like so:
You can use the Jaeger UI (by default running on http://localhost:16686/) to query for this span and see all of the traces for the current Tilt run. These traces are made available immediately as you use Tilt. You don't need to wait until after Tilt has stopped to get access to the tracing data.
tilt uses a web interface for logs investigation.
By default, the web interface runs on port 10350.
When you use a released version of Tilt, all the HTML, CSS, and JS assets are served from our production bucket.
When you build Tilt from head, the Tilt binary will default to development mode. When you run Tilt, it will run a webpack dev server as a separate process on port 46764, and reverse proxy all asset requests to the dev server.
To manually control the assets served, you can use:
tilt up --web-mode=local
to force Tilt to use the webpack dev server, or you can use
tilt up --web-mode=prod
to force Tilt to use production assets.
To run the server on an alternate port (e.g. 8001):
tilt up --port=8001
The landing page and documentation lives in the tilt.build repo.
We write our docs in Markdown and generate static HTML with Jekyll.
Netlify will automatically deploy the docs to the public site when you merge to master.
We use goreleaser for releases.
go get -u github.com/goreleaser/goreleaser
GITHUB_TOKENenv variable with repo scope
Currently, releases have to be built on MacOS due to cross-compilation issues with Apple FSEvents. Cross-compiling a Linux target binary with a MacOS toolchain works fine.
To create a new release at tag
git fetch --tags git tag -a v0.0.1 -m "my release" git push origin v0.0.1 make release
goreleaser will build binaries for the latest tag (using semantic version to determine "latest"). Check the current releases to figure out what the latest release ought to be.
- If adding backwards-compatible functionality increment the patch version (0.x.Y).
- If adding backwards-incompatible functionality increment the minor version (0.X.y). We would probably write a blog post about this.
Releasing the Synclet
Releasing a synclet should be very infrequent, because the amount of things it
does is small. (It's basically an optimization over
kubectl exec, and restarting a container.)
To release a synclet, run
make synclet-release. This will automatically:
- Publish a new synclet image tagged with the current date
- Update sidecar.go with the new tag
Then submit the PR. The next time someone releases Tilt, it will use the new image tag.