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# OxygenFlow |
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|
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[](https://oxygenhub.io/andymccall/oxygenflow/flow) |
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|
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Hermetic pipelines for Oxygen repositories: |
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|
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- a typed pipeline in `.flow/pipeline.kdl` |
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- jobs run in isolation tiers, Firecracker microVMs by default |
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- the host writes the receipts |
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- results go to OxygenHub as checks and appear on its Flow tab |
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|
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The specification is [docs/spec.md](docs/spec.md). What works today is |
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[docs/m0.md](docs/m0.md). |
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|
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## A pipeline |
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|
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```kdl |
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schema-version 1 |
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|
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sandbox "alpine" { |
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runtime "microvm" |
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rootfs "cas://blob/…" // printed by `flow rootfs import` |
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memory-limit "256MiB" |
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network "isolated" |
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} |
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|
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job "build" { |
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sandbox "alpine" |
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exec "make" |
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} |
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|
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job "test" { |
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sandbox "alpine" |
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depends-on "build" |
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exec "sh" "-eu" "test.sh" // argv, run as written: no shell unless you name one |
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} |
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``` |
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|
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Each job boots its own microVM: |
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|
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- it has no network device |
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- the rootfs is read-only |
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- the workspace is the state being built, read-write at `/src` |
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- the job runs as a user that is not root |
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|
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This repository's own pipeline is [.flow/pipeline.kdl](.flow/pipeline.kdl). |
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The stamp at the top of this page is its result on OxygenHub. It shows the |
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run of the state you are viewing, not whatever the bookmark holds now, and |
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it names the state and each job's receipt. |
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|
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## Commands |
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|
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flow check # validate .flow/pipeline.kdl, print jobs and the pipeline hash |
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flow run [JOB…] # run the pipeline on this directory, locally, in microVMs |
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flow rootfs import T.tgz --sha256 HEX # make a rootfs image; prints the `rootfs` line to pin |
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flow rootfs list |
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flow hash FILE # BLAKE3, for pinning in flow.toml |
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flow runner # claim and run jobs for the hub in flow.toml |
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|
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## A Flow home |
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|
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`$FLOW_HOME` (default `~/.local/share/flow`) holds: |
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|
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- `flow.toml` |
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- the pinned Firecracker binary, guest kernel and `flow-init` |
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- rootfs images under `cas/` |
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- scratch space |
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|
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Every pinned file is checked against its BLAKE3 before use. |
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|
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```toml |
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[microvm] |
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firecracker = { path = "bin/firecracker", blake3 = "…" } |
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kernel = { path = "kernel/vmlinux", blake3 = "…" } |
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init = { path = "bin/flow-init", blake3 = "…" } |
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|
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[runner] # only for `flow runner` |
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hub = "https://hub.example:7343" |
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token = "…" # listed in the hub's [flow] runner_tokens |
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ca = "/path/to/hub-ca.pem" # when the hub's certificate is self-signed |
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name = "runner-1" |
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``` |
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Setting one up needs Linux x86-64 with KVM and e2fsprogs 1.43 or later: |
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1. Build `flow` with `cargo build --release -p flow`. Build the guest init |
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as a static binary: |
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`RUSTFLAGS="-C target-feature=+crt-static" cargo build --release -p flow-init --target x86_64-unknown-linux-gnu`. |
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2. Download Firecracker v1.17.0 from its GitHub release, and check the |
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published SHA-256. Download the guest kernel |
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`firecracker-ci/v1.15/x86_64/vmlinux-6.1.155` from Firecracker's CI |
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bucket. |
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3. Run `flow rootfs import alpine-minirootfs-3.24.2-x86_64.tar.gz --sha256 …`. |
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4. Write `flow.toml`, pinning each file by its `flow hash`. |
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|
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On OxygenHub, `hub.toml` lists the runner token and the repositories whose |
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pushes run pipelines: |
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|
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```toml |
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[flow] |
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runner_tokens = ["…"] |
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repos = ["owner/*"] |
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``` |
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|
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## Tests |
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|
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`cargo test --workspace` runs every test that needs no VM. The microVM |
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conformance test also runs when `FLOW_TEST_HOME` names a Flow home and |
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`FLOW_TEST_ROOTFS` is the hash of an Alpine rootfs in it. The test checks |
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literal argv, network isolation, the read-only rootfs, and that dependents |
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are skipped after a failure. |