Ship batesd as a Mix release; fix bates start crash#32
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PR #31 added a `bates start` subcommand to the existing escript, but it crashed immediately because escripts cannot carry `erlexec`'s `priv/exec-port` C binary. The escript packaging format is the wrong tool for the daemon. This removes `Bates.CLI.Start`, the dispatcher clause that routed `start` to it, the `bates start` line in the usage banner, and the test file. The matching usage assertion in `Bates.CLITest` is updated. A subsequent commit will reintroduce the daemon as a Mix release named `batesd` so `erlexec`'s priv directory is available at runtime.
The control commands previously told users to run `bates start` when the daemon was unreachable. With `bates start` removed and the daemon shipping as a Mix release named `batesd`, the diagnostic now reads "Bates is not running. Start it with: batesd." Also rewords `Bates.Prerequisites` and `Bates.CLI.Setup` docstrings to describe the gates and setup work in terms of `batesd`.
Move the argv parser, config-path application, and prereq verifier that the doomed `Bates.CLI.Start` owned into `Bates.Application.start/2` so the same supervision tree boots correctly under both `mix phx.server` and `bin/batesd` (the upcoming Mix release). The work lives in a new `Bates.Daemon` module as three pure helpers (`parse_argv/1`, `apply_options/1`, `verify_prerequisites/0`) so each piece is unit-testable without trapping `System.halt/1`. `start/2` itself is a thin orchestrator that halts with code 2 on parse or prereq failures, matching what `bates start` used to do. Tests run `Application.start/2` because `:bates` is a started application. To keep them from tripping the prereq gate (or being rejected by the argv parser, which sees `["test"]`), `config/test.exs` sets `config :bates, skip_prereq_check: true`, and `start/2` short- circuits the entire boot prep when that flag is set. The default of `false` keeps the gate active in dev and in the release. `Bates.Daemon` does NOT call `Mix.env/0` or any other build-time module: `Mix` is unavailable in releases. New `Bates.DaemonTest` covers `--config` parsing (default + override), unknown-switch and unexpected-positional rejection, application of the parsed `--config` to `:bates, :config_path`, and the prereq diagnostic when `caddy` is off `$PATH`.
Declare a `batesd` Mix release in `source/mix.exs`'s `releases:` keyword. The release embeds ERTS, includes every dependency's `priv/` directory, and starts `:bates` permanently — so `erlexec` finds its `exec-port` C binary at runtime, which the escript packaging format could not deliver. `mix release` generates `bin/batesd` as a multi-subcommand dispatcher (`start`, `daemon`, `remote`, `eval`, ...). A custom `:steps` callback (`install_launcher/1`) renames that file to `bin/batesd-orig` and writes a thin wrapper at `bin/batesd` that always invokes the foreground `start` subcommand. Users see a single command: `batesd [--config <path>]` — no subcommand maze. The wrapper is written directly inside the `:steps` callback rather than via `rel/overlays/`. Overlays are copied during `:assemble`, which makes the rename-then-overlay sequence awkward; doing the rename and the wrapper write in the same custom step keeps the ordering obvious. Add a minimal `config/prod.exs` so `MIX_ENV=prod mix release batesd` can read environment-specific endpoint settings. The file mirrors `dev.exs` for now (port and `secret_key_base`); follow-up work can diverge as needed. `config/runtime.exs` is intentionally absent — the release reads its only environment-dependent setting (`--config <path>`) from argv inside `Bates.Application.start/2`.
`specs/cli.md` removes the `### bates start` section and the option table that came with it, points the not-running message at `batesd`, points the configuration override description at `batesd`, and rewords the "How It Connects" `bates start` bullet to describe `batesd`. A new `## Daemon` section documents `batesd`'s flags, prereq behavior, and intended invocation (foreground until the launchd v2 proposal lands). The intro paragraph now describes the two binaries explicitly. `specs/system-overview.md`'s `### CLI` section now spells out the two-binary topology: `batesd` is the server (Mix release, embeds ERTS so `erlexec` finds its priv binary), and `bates` is a thin client escript for the control commands.
Add a "Build and Run" section between "Setup" and "Configuration" covering both binaries: `mix escript.build` for the `bates` client and `MIX_ENV=prod mix release batesd` for the daemon. Includes the `--config` flag, the foreground/Ctrl-C semantics, and a couple of sample `bates` invocations against a running daemon.
The mix-release `start` subcommand discards extra argv, and the generated `elixir` launcher's CLI mode interprets argv as `[script | args]` (so passing `--config` directly would make it treat the flag as a script filename). Have the `bin/batesd` wrapper parse `--config` in shell and export it as the `BATES_CONFIG_PATH` environment variable, then add `Bates.Daemon.apply_env/1` to plumb that into `:bates, :config_path`. `Bates.Application.start/2` now runs the env step after argv so the env var wins when both are set (the wrapper sets it deliberately; the argv path stays for `mix phx.server`).
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Context
PR #31 added a
bates startsubcommand to the existing escript, but itcrashes immediately because escripts cannot carry
erlexec'spriv/exec-portC binary. The escript packaging format is the wrong toolfor the daemon. This PR splits Bates into two binaries:
batesstays asan escript for the six fast-cold-start control commands, and the daemon
ships as a Mix release named
batesd.Summary
bates startsubcommand and its module + tests.--config <path>) and prerequisite verificationinto
Bates.Application.start/2(viaBates.Daemon), so thesupervision tree boots the same way under
mix phx.server(dev/test)and
bin/batesd(release).releases:keyword tomix.exsdeclaring thebatesdreleasewith a custom
:stepscallback that installs a thinbin/batesdwrapper. The wrapper parses
--configin shell, exportsBATES_CONFIG_PATH, and execs the underlying mix-release launcher'sstartsubcommand. The daemon picks upBATES_CONFIG_PATHviaBates.Daemon.apply_env/1. (See execution notes in the archived planfor why the env-var path was needed instead of plain argv forwarding.)
config :bates, skip_prereq_check: trueinconfig/test.exssomix testdoesn't trip the prereq gate on dev machines withoutcaddyon$PATH.config/prod.exsso the prod release assembles.batesd, notbates start.specs/cli.mdandspecs/system-overview.mdfor the newtwo-binary topology.
Test plan
The agent has run automated checks. The sections below need to be
verified by hand before merge — they require live Caddy / DNS resolver
and real services to bring up.
mix testfromsource/passes (235 tests, 0 failures).mix format --check-formattedpasses.MIX_ENV=prod mix release batesdsucceeds and produces_build/prod/rel/batesd/bin/batesd._build/prod/rel/batesd/bin/batesd --helpdoes NOT print themix-release subcommand list (the wrapper took).
_build/prod/rel/batesd/bin/batesd --bogusexits 2 with ourusage message.
BATES_CONFIG_PATH=/tmp/x.toml batesd-orig eval ...confirms thedaemon reads the env var into
:bates, :config_path._build/prod/rel/batesd/bin/batesdboots and serves the dashboardat
https://bates.test.bates status,bates up <app>,bates env <app>all workagainst the running daemon.
bin/batesd --config /path/to/foo.tomlhonors the override.batesdwhile one is already up exits with aport-bind error.