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Adopt golib/pg for migrations and pool construction
encapi's schema was a cumulative IF NOT EXISTS blob re-executed inline on every
start: it grows forever, records nothing, and cannot express a change that is
not a fresh CREATE. golib owns that mechanism now, so encapi keeps the SQL and
drops the runner.

- Move the DDL verbatim into migrations/0001_init.sql, embedded via
  migrations.FS. It stays IF NOT EXISTS-guarded, so the first start against the
  live database re-runs it as a no-op and only lands the schema_migrations row.
- Build the pool with pg.NewMigrated under the advisory lock named
  encapi-migrations, and delete the inline migrate(). database.New now takes a
  context and a logger; main.go hands it the signal context so a start blocked
  on the migration lock still dies on SIGTERM.
- Render the DSN with pg.DSN. The env var contract is untouched — the fields are
  still resolved by internal/config, because encapi defaults DBUSER and DBNAME
  to "encapi" where pg.DSNFromEnv treats both as required.
- Guard the set: embedded files must match migrations/, every CREATE must be
  idempotent, the derived lock key is pinned, and a container test proves the
  adoption path over a database that predates schema_migrations.
- Plumb GOPRIVATE=git.unkin.net for the first cross-repo Go dependency:
  exported by the Makefile, set in the Dockerfile and the woodpecker Go steps,
  documented in the README.
2026-09-02 00:17:04 +10:00

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Markdown

# encapi
A Postgres-backed **External Node Classifier (ENC)** for Puppet, written in Go.
It replaces Cobbler as the source of truth for *which role a host runs* while
keeping Puppet's node-classification contract byte-compatible.
## Components
| Binary | What it is |
|-----------------|-----------------------------------------------------------------------|
| `encapi` | HTTP server: serves ENC documents + a read/write API. Postgres-backed. |
| `encapi-cli` | CLI over the API. `encapi-cli classify <host>` is the Puppet ENC. |
| `encapi-enc` | Thin wrapper (shipped in the RPM) for Puppet's `external_nodes`. |
The Terraform provider lives in a sibling repo:
[`terraform-provider-encapi`](https://git.unkin.net/unkin/terraform-provider-encapi).
## Data model
- **status** — a Puppet environment (Cobbler's "status": testing, production…).
- **role** — a class assignment target (`roles::infra::storage::vault`) with
inheritable `default_params`.
- **node** — a host (certname) pinned to one role + one environment, with
optional per-node `params` (which win over the role defaults).
Foreign keys guarantee a node can only reference a role/status that exists, and
a role/status in use cannot be deleted.
## Schema migrations
The SQL lives in [`migrations/`](migrations), is embedded in the `encapi`
binary, and is applied at startup before the server listens — there is no
mirrored copy in the deployment to drift out of sync.
The runner is [`golib/pg`](https://git.unkin.net/unkin/golib)'s
`pg.NewMigrated`: encapi owns the SQL, the shared library owns the mechanics.
Each start takes `pg_advisory_lock` on a key derived from the lock name
`encapi-migrations`, creates `schema_migrations` (`version`, `applied_at`) if
missing, and applies every embedded file whose filename is not yet recorded — in
lexical (version) order, each file's SQL and its tracking row in one transaction
— then unlocks. Replicas starting together queue on the lock and then find
nothing to do.
A file the live database already satisfies but `schema_migrations` does not
record is re-run, which is how the pre-migration schema is adopted: migrations
are `IF NOT EXISTS`-guarded, so the re-run is a no-op that only lands the
tracking row. Add schema changes as a new numbered file; never edit an applied
one.
## ENC output
`encapi` renders two shapes from the same data:
- **`GET /api/v1/nodes/{certname}/enc`** — the reshaped document Puppet's
`exec` terminus consumes: `classes` as a list, `environment` dropped when it
is `testing`, and `parameters` carrying `enc_role` (list) + `enc_env`. This is
what `encapi-cli classify` prints.
- **`GET /cblr/svc/op/puppet/hostname/{certname}`** — the cobbler-wire form
(`classes` as a map, `environment` always present), so the legacy
`enc_direct_facts.rb` fact can be repointed with only a URL change.
See [`docs/cutover.md`](docs/cutover.md) for the migration from Cobbler.
## API
Reads are open. Writes require `Authorization: Bearer $ENCAPI_WRITE_TOKEN`
(set the token in the server's environment; manage it in Vault).
```
GET /healthz
GET /api/v1/nodes list nodes
GET /api/v1/nodes/{certname} get node
PUT /api/v1/nodes/{certname} upsert node (token)
DELETE /api/v1/nodes/{certname} delete node (token)
GET /api/v1/nodes/{certname}/enc reshaped ENC (YAML)
GET /cblr/svc/op/puppet/hostname/{h} cobbler-wire ENC (YAML)
GET /api/v1/roles ... /roles/{name} (PUT/DELETE token)
GET /api/v1/statuses ... /statuses/{name} (PUT/DELETE token)
```
## Configuration (server env)
| Var | Default | Purpose |
|------------------------|---------------|------------------------------------------|
| `LISTEN_ADDR` | `:8000` | listen address |
| `DBHOST/DBPORT/DBUSER/DBPASS/DBNAME/DBSSL` | localhost/5432/encapi/encapi/encapi/disable | Postgres |
| `ENCAPI_WRITE_TOKEN` | *(unset)* | bearer token for writes; unset = read-only |
| `ENCAPI_DISTRO_API_URL`| *(unset)* | optional kickstart/distro API for provisioning params |
## CLI
```bash
export ENCAPI_URL=https://encapi.k8s.syd1.au.unkin.net
export ENCAPI_WRITE_TOKEN=… # only needed for writes
encapi-cli status set production
encapi-cli role set roles::infra::storage::minio --param 'replicas=4' --param 'epel="9"'
encapi-cli node set ausyd1nxvm2100.main.unkin.net --role roles::infra::storage::minio --env production
encapi-cli classify ausyd1nxvm2100.main.unkin.net
# one-shot migration from the live Cobbler estate:
encapi-cli import-cobbler --dry-run
encapi-cli import-cobbler
```
## Local development
```bash
docker compose up -d # postgres + encapi
make test # full suite (Postgres via testcontainers)
make test-short # skip container-backed DB tests
```
### `GOPRIVATE`
encapi depends on `git.unkin.net/unkin/golib`, which is served by Gitea and is
unknown to `proxy.golang.org` / `sum.golang.org`. Module resolution therefore
needs:
```
export GOPRIVATE=git.unkin.net
```
The `Makefile` exports it for every target, and the `Dockerfile` and the
woodpecker Go steps set it themselves, so `make build|test|lint` and CI work on
a clean checkout. Only bare `go` commands run outside `make` need it in your
shell — set it there (or in your shell profile) rather than with `go env -w`,
which is machine state this repo cannot carry.
## Releases
- **`encapi` server image** — tagging `vX.Y.Z` builds and pushes
`artifactapi.k8s.syd1.au.unkin.net/docker-internal/encapi:{tag,latest}` (distroless).
- **`encapi-cli` RPM** — the same tag builds an RPM (nfpm) and publishes it to
the ArtifactAPI `rpm-internal` repo. Installs `encapi-cli`, the `encapi-enc`
Puppet wrapper, and `/etc/encapi/enc.conf`.