Project: LinuxKit (Provisioning / Automation & Configuration)
File: BUILDING.md

This guide is useful if you intend to contribute on containerd. Thanks for your effort. Every contribution is very appreciated. This doc includes: To build the `containerd` daemon, and the `ctr` simple test client, the following build system dependencies are required: Go 1.13.x or above except 1.14.x Protoc 3.x compiler and headers (download at the ) Btrfs headers and libraries for your distribution. Note that building the btrfs driver can be disabled via the build tag `no_btrfs`, removing this dependency. First you need to setup your Go development environment. You can follow this guideline and at the end you have `go` command in your `PATH`. You need `git` to checkout the source code: ```sh git clone https://github.com/containerd/containerd ``` For proper results, install the `protoc` release into `/usr/local` on your build system. For example, the following commands will download and install the 3.11.4 release for a 64-bit Linux host: ``` $ wget -c https://github.com/google/protobuf/releases/download/v3.11.4/protoc-3.11.4-linux-x86_64.zip $ sudo unzip protoc-3.11.4-linux-x86_64.zip -d /usr/local ``` `containerd` uses it means that you need to satisfy these dependencies in your system: CentOS/Fedora: `yum install btrfs-progs-devel` Debian/Ubuntu: `apt-get install btrfs-progs libbtrfs-dev` Debian(before Buster)/Ubuntu(before 19.10): `apt-get install btrfs-tools` At this point you are ready to build `containerd` yourself! `runc` is the default container runtime used by `containerd` and is required to run containerd. While it is okay to download a runc binary and install that on the system, sometimes it is necessary to build runc directly when working with container runtime development. You can skip this step if you already have the correct version of `runc` installed. `runc` requires `libseccomp`. You may need to install the missing dependencies: CentOS/Fedora: `yum install libseccomp libseccomp-devel` Debian/Ubuntu: `apt-get install libseccomp libseccomp-dev` For the quick and dirty installation, you can use the following: ``` git clone https://github.com/opencontainers/runc cd runc make sudo make install ``` Make sure to follow the guidelines for versioning in for the best results. `containerd` uses `make` to create a repeatable build flow. It means that you can run: ``` cd containerd make ``` This is going to build all the project binaries in the `./bin/` directory. You can move them in your global path, `/usr/local/bin` with: ```sudo sudo make install ``` When making any changes to the gRPC API, you can use the installed `protoc` compiler to regenerate the API generated code packages with: ```sudo make generate ``` Note: Several build tags are currently available: `no_btrfs`: A build tag disables building the btrfs snapshot driver. `no_cri`: A build tag disables building Kubernetes support into containerd. See for build tags of CRI plugin. `no_devmapper`: A build tag disables building the device mapper snapshot

For example, adding `BUILDTAGS=no_btrfs` to your environment before calling the binaries Makefile target will disable the btrfs driver within the containerd Go build. Vendoring of external imports uses the . You need to use `go mod` command to modify the dependencies. After modifition, you should run `go mod tidy` and `go mod vendor` to ensure the `go.mod`, `go.sum` files and `vendor` directory are up to date. Changes to these files should become a single commit for a PR which relies on vendored updates. Please refer to for the currently supported version of `runc` that is used by containerd. You can build static binaries by providing a few variables to `make`: ```sudo make EXTRA_FLAGS="-buildmode pie" \ EXTRA_LDFLAGS='-linkmode external -extldflags "-fno-PIC -static"' \ BUILDTAGS="netgo osusergo static_build" ``` Note: static build is discouraged static containerd binary does not support loading shared object plugins (`*.so`) The following instructions assume you are at the parent directory of containerd source directory. You can build `containerd` via a Linux-based Docker container. You can build an image from this `Dockerfile`: ``` FROM golang RUN apt-get update && \ apt-get install -y libbtrfs-dev ``` Let's suppose that you built an image called `containerd/build`. From the containerd source root directory you can run the following command: ```sh docker run -it \ -v ${PWD}/containerd:/go/src/github.com/containerd/containerd \ -e GOPATH=/go \ -w /go/src/github.com/containerd/containerd containerd/build sh ``` This mounts `containerd` repository You are now ready to : ```sh make && make install ``` To have complete core container runtime, you will need both `containerd` and `runc`. It is possible to build both of these via Docker container. You can use `git` to checkout `runc`: ```sh git clone https://github.com/opencontainers/runc ``` We can build an image from this `Dockerfile`: ```sh FROM golang RUN apt-get update && \ apt-get install -y libbtrfs-dev libseccomp-dev ``` In our Docker container we will use a specific `runc` build which includes and support. Hence why our Dockerfile includes `libseccomp-dev` as a dependency (apparmor support doesn't require external libraries). Please refer to for the currently supported version of `runc` that is used by containerd. Let's suppose you build an image called `containerd/build` from the above Dockerfile. You can run the following command: ```sh docker run -it --privileged \ -v /var/lib/containerd \ -v ${PWD}/runc:/go/src/github.com/opencontainers/runc \ -v ${PWD}/containerd:/go/src/github.com/containerd/containerd \ -e GOPATH=/go \ -w /go/src/github.com/containerd/containerd containerd/build sh ``` This mounts both `runc` and `containerd` repositories in our Docker container. From within our Docker container let's build `containerd`: ```sh cd /go/src/github.com/containerd/containerd make && make install ``` These binaries can be found in the `./bin` directory in your host. `make install` will move the binaries in your `$PATH`. Next, let's build `runc`: ```sh cd

make BUILDTAGS='seccomp apparmor selinux' && make install ``` When working with `ctr`, the simple test client we just built, don't forget to start the daemon! ```sh containerd --config config.toml ``` During the automated CI the unit tests and integration tests are run as part of the PR validation. As a developer you can run these tests locally by using any of the following `Makefile` targets: `make test`: run all non-integration tests that do not require `root` privileges `make root-test`: run all non-integration tests which require `root` `make integration`: run all tests, including integration tests and those which require `root`. `TESTFLAGSPARALLEL` can be used to control parallelism. For example, `TESTFLAGSPARALLEL=1 make integration` will lead a non-parallel execution. The default value of `TESTFLAGS_PARALLEL` is 8. To execute a specific test or set of tests you can use the `go test` capabilities without using the `Makefile` targets. The following examples show how to specify a test name and also how to use the flag directly against `go test` to run root-requiring tests. ```sh go test -v -run "<TEST_NAME>" . go test -v -run . -test.root ``` Example output from directly running `go test` to execute the `TestContainerList` test: ```sh sudo go test -v -run "TestContainerList" . -test.root INFO[0000] running tests against containerd revision=f2ae8a020a985a8d9862c9eb5ab66902c2888361 version=v1.0.0-beta.2-49-gf2ae8a0 === RUN TestContainerList PASS: TestContainerList (0.00s) PASS ok github.com/containerd/containerd 4.778s ``` In addition to `go test`-based testing executed via the `Makefile` targets, the `containerd-stress` tool is available and built with the `all` or `binaries` targets and installed during `make install`. With this tool you can stress a running containerd daemon for a specified period of time, selecting a concurrency level to generate stress against the daemon. The following command is an example of having five workers running for two hours against a default containerd gRPC socket address: ```sh containerd-stress -c 5 -t 120 ``` For more information on this tool's options please run `containerd-stress --help`. is an external tool which can be used to drive load against a container runtime, specifying a particular set of lifecycle operations to run with a specified amount of concurrency. Bucketbench is more focused on generating performance details than simply inducing load against containerd. Bucketbench differs from the `containerd-stress` tool in a few ways: Bucketbench has support for testing the Docker engine, the `runc` binary, and containerd 0.2.x (via `ctr`) and 1.0 (via the client library) branches. Bucketbench is driven via configuration file that allows specifying a list of lifecycle operations to execute. This can be used to generate detailed statistics per-command (e.g. start, stop, pause, delete). Bucketbench generates detailed reports and timing data at the end of the configured test run. More details on how to install and run `bucketbench` are available at the .