| 1 |
# OxygenFlow |
| 2 |
|
| 3 |
Hermetic pipelines for Oxygen repositories: |
| 4 |
|
| 5 |
- a typed pipeline in `.flow/pipeline.kdl` |
| 6 |
- jobs run in isolation tiers, Firecracker microVMs by default |
| 7 |
- the host writes the receipts |
| 8 |
- results go to OxygenHub as checks and appear on its Flow tab |
| 9 |
|
| 10 |
The specification is [docs/spec.md](docs/spec.md). What works today is |
| 11 |
[docs/m0.md](docs/m0.md). |
| 12 |
|
| 13 |
## A pipeline |
| 14 |
|
| 15 |
```kdl |
| 16 |
schema-version 1 |
| 17 |
|
| 18 |
sandbox "alpine" { |
| 19 |
runtime "microvm" |
| 20 |
rootfs "cas://blob/…" // printed by `flow rootfs import` |
| 21 |
memory-limit "256MiB" |
| 22 |
network "isolated" |
| 23 |
} |
| 24 |
|
| 25 |
job "build" { |
| 26 |
sandbox "alpine" |
| 27 |
exec "make" |
| 28 |
} |
| 29 |
|
| 30 |
job "test" { |
| 31 |
sandbox "alpine" |
| 32 |
depends-on "build" |
| 33 |
exec "sh" "-eu" "test.sh" // argv, run as written: no shell unless you name one |
| 34 |
} |
| 35 |
``` |
| 36 |
|
| 37 |
Each job boots its own microVM: |
| 38 |
|
| 39 |
- it has no network device |
| 40 |
- the rootfs is read-only |
| 41 |
- the workspace is the state being built, read-write at `/src` |
| 42 |
- the job runs as a user that is not root |
| 43 |
|
| 44 |
This repository's own pipeline is [.flow/pipeline.kdl](.flow/pipeline.kdl). |
| 45 |
|
| 46 |
## Deploying the runner on Earth |
| 47 |
|
| 48 |
`make deploy-runner` builds `flow` and the static `flow-init`, installs them |
| 49 |
under `/home/claude/flow` (keeping the previous files as `.prev`), re-pins |
| 50 |
`flow-init` in `flow.toml` and restarts the `flow-runner` service. |
| 51 |
|
| 52 |
## Commands |
| 53 |
|
| 54 |
flow check # validate .flow/pipeline.kdl, print jobs and the pipeline hash |
| 55 |
flow run [JOB…] # run the pipeline on this directory, locally, in microVMs |
| 56 |
flow rootfs import T.tgz --sha256 HEX # make a rootfs image; prints the `rootfs` line to pin |
| 57 |
flow rootfs list |
| 58 |
flow hash FILE # BLAKE3, for pinning in flow.toml |
| 59 |
flow runner # claim and run jobs for the hub in flow.toml |
| 60 |
|
| 61 |
## A Flow home |
| 62 |
|
| 63 |
`$FLOW_HOME` (default `~/.local/share/flow`) holds: |
| 64 |
|
| 65 |
- `flow.toml` |
| 66 |
- the pinned Firecracker binary, guest kernel and `flow-init` |
| 67 |
- rootfs images under `cas/` |
| 68 |
- scratch space |
| 69 |
|
| 70 |
Every pinned file is checked against its BLAKE3 before use. |
| 71 |
|
| 72 |
```toml |
| 73 |
[microvm] |
| 74 |
firecracker = { path = "bin/firecracker", blake3 = "…" } |
| 75 |
kernel = { path = "kernel/vmlinux", blake3 = "…" } |
| 76 |
init = { path = "bin/flow-init", blake3 = "…" } |
| 77 |
|
| 78 |
[runner] # only for `flow runner` |
| 79 |
hub = "https://hub.example:7343" |
| 80 |
token = "…" # listed in the hub's [flow] runner_tokens |
| 81 |
ca = "/path/to/hub-ca.pem" # when the hub's certificate is self-signed |
| 82 |
name = "runner-1" |
| 83 |
``` |
| 84 |
|
| 85 |
Setting one up needs Linux x86-64 with KVM and e2fsprogs 1.43 or later: |
| 86 |
|
| 87 |
1. Build `flow` with `cargo build --release -p flow`. Build the guest init |
| 88 |
as a static binary: |
| 89 |
`RUSTFLAGS="-C target-feature=+crt-static" cargo build --release -p flow-init --target x86_64-unknown-linux-gnu`. |
| 90 |
2. Download Firecracker v1.17.0 from its GitHub release, and check the |
| 91 |
published SHA-256. Download the guest kernel |
| 92 |
`firecracker-ci/v1.15/x86_64/vmlinux-6.1.155` from Firecracker's CI |
| 93 |
bucket. |
| 94 |
3. Run `flow rootfs import alpine-minirootfs-3.24.2-x86_64.tar.gz --sha256 …`. |
| 95 |
4. Write `flow.toml`, pinning each file by its `flow hash`. |
| 96 |
|
| 97 |
On OxygenHub, `hub.toml` lists the runner token and the repositories whose |
| 98 |
pushes run pipelines: |
| 99 |
|
| 100 |
```toml |
| 101 |
[flow] |
| 102 |
runner_tokens = ["…"] |
| 103 |
repos = ["owner/*"] |
| 104 |
``` |
| 105 |
|
| 106 |
## Tests |
| 107 |
|
| 108 |
`cargo test --workspace` runs every test that needs no VM. The microVM |
| 109 |
conformance test also runs when `FLOW_TEST_HOME` names a Flow home and |
| 110 |
`FLOW_TEST_ROOTFS` is the hash of an Alpine rootfs in it. The test checks |
| 111 |
literal argv, network isolation, the read-only rootfs, and that dependents |
| 112 |
are skipped after a failure. |
| 113 |
|
| 114 |
## oxygen as a pinned subrepo |
| 115 |
|
| 116 |
`flow` builds against `deps/oxygen`, a subrepo (`oxy submodule`) pinned to an exact state, so builds are reproducible and OxygenFlow can build this repository without network. `make pins` moves it to oxygen's `main` on Earth (push oxygen first); the next commit records the new pin. Format only this workspace, `cargo fmt -p flow -p flow-core -p flow-init`: `--all` also reaches `deps/`. After a fresh clone, `oxy submodule update --init` fetches it. |