initial commit: docker test-build toolchain

Extracted from the .extras/ dir of the sbo-slackbuilds package repo, where it
grew from a throwaway helper into a standalone tool. Git history starts fresh;
the original 41-commit development log is preserved in HISTORY.md.

Contents: the test-build CLI (resolves a local SlackBuild's deps from a
configured SBo tree and builds it in a throwaway container, lints, caches deps),
the image-builder chain that produces the images it consumes, their pure-logic
self-checks, design specs/plans, an install.sh for ~/bin, and docs.

Licensed GPLv2-only.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

1 files changed, 258 insertions, 0 deletions

diff --git a/docs/specs/2026-07-13-docker-test-build-design.md b/docs/specs/2026-07-13-docker-test-build-design.md
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+# Docker test-build script - design
+
+Date: 2026-07-13
+
+## Purpose
+
+A single bash script that verifies an already-published SBo package still
+builds cleanly on a target Slackware version, inside a throwaway docker
+container. This is the "test-build" step of this repo's maintenance loop
+(track upstream -> bump -> **test-build** -> make tarball).
+
+The container is disposable, so unlike a real `slackrepo build` this runs
+directly (no host install), and Claude may run it (per the repo's
+`Who builds SlackBuilds` exception).
+
+## Scope and non-goals
+
+- One target package per run: `test-build <pkg>`.
+- Two Slackware targets: `-current` (default) and `15.0` (`--stable`).
+- Resolves the target's SBo dependency tree from the LOCAL SBo tree, builds
+  deps then target in the container, reports, discards everything.
+- NOT a redistributable-package builder. The container's built `.txz` is
+  throwaway; the SBo submission tarball is made separately (post-commit hook)
+  only after a green run.
+- Does NOT wrap slackrepo or sbo-batch-test. It REUSES sbo-batch-test's
+  resolver + build logic, adapted, but is an independent script.
+- Shares the host kernel (docker). No kernel-module build claims.
+
+## Why not the overlay approach (sbo-batch-test)
+
+`sbo-batch-test` already resolves deps + builds + reports, but against a
+LOCAL overlayfs over a 15.0 base. In docker the container IS the disposable
+base, and overlayfs-over-docker-storage (itself overlayfs) is fragile. So we
+drop the overlay layer and build directly in the container. We port
+sbo-batch-test's dep resolver and its `build_one` chroot heredoc
+(download -> md5 -> build -> installpkg -> status token) into a `docker run`.
+
+## Architecture
+
+Single self-contained bash script (`test-build`, location TBD in
+implementation - likely `.extras/`). Host does resolution + orchestration;
+the container does the actual building.
+
+```
+host: parse args, load config
+host: pick version -> image tag + SBo tree
+host: resolve dep tree (local tree, topo sort)   [ported from sbo-batch-test]
+host: apply current-vs-stable overrides
+host: print final build order, Y/n confirm       (--yes: still prints first)
+  docker run --rm -v <tree>:ro -v <pkg>:ro -v <cache/digest>:ro <image>:
+    for each dep in order:
+      cache hit (version match) -> installpkg from cache  (CACHED)
+      else                      -> download/md5/build/installpkg + cache
+    target:                     download/md5/build/installpkg (always fresh)
+    target: sbopkglint on the built .txz
+host: collect per-package results, print color summary
+container discarded (--rm)
+```
+
+### Images (external input, not built by this script)
+
+The script does NOT build images. It consumes a ready image per version,
+tagged locally:
+
+- current: `sbo-testbuild:current`
+- 15.0:    `sbo-testbuild:15.0`
+
+Each image is a FULL, patched Slackware install (SBo tests against a full
+install; a minimal base causes false "missing dependency" results, a lesson
+from sbo-batch-tester) plus `sbo-maintainer-tools` (for `sbopkglint`) and
+`sbopkg` configured to that version's SBo repo (`:current` -> -current repo,
+`:15.0` -> 15.0 repo).
+
+**How the images are produced is out of scope for this script.** A separate
+nightly job (a LAN machine, images stored on the NAS, later served from a
+local registry) builds and refreshes them. That builder is its own tool,
+specced separately.
+
+For now the script assumes the tagged image is present locally: it runs
+`docker run` against the tag and errors with a clear message if the image is
+missing (pointing at the image-builder job). When the local registry exists,
+a `docker pull` of the tag slots in ahead of the run via the same config,
+no other change.
+
+Per-run cost is just the SlackBuild's own build time + ~1s container start.
+
+### Config (external file)
+
+`~/.config/sbo-testbuild/config`, empty defaults in-script, sourced if
+present (same pattern as sbo-batch-test). Keys:
+
+```sh
+SBO_TREE_CURRENT=/path/to/SBo-current   # local SBo tree, -current
+SBO_TREE_STABLE=/path/to/SBo-15.0       # local SBo tree, 15.0
+IMAGE_CURRENT=sbo-testbuild:current     # ready image tag (built elsewhere)
+IMAGE_STABLE=sbo-testbuild:15.0
+LOG_ROOT=/path/to/logs
+PKG_CACHE=/path/to/cache                 # dep cache; empty = disabled
+```
+
+The version flag selects BOTH the image and the tree together (default
+current; `--stable` / `15.0` switches both), so tree and image never mismatch.
+
+### current-vs-stable overrides
+
+A data file next to the config, `~/.config/sbo-testbuild/overrides`. It
+encodes the known deltas between building on 15.0 and on -current. Applied
+ONLY when the target version is `-current` (15.0 is the SBo baseline). Three
+rule kinds:
+
+```
+# dep present in 15.0 but already in -current base -> drop from order
+drop:   rust
+# dep renamed on -current -> map old -> new before lookup
+rename: python3-foo -> foo
+# dep removed from the -current tree -> fetch from SBo instead of local tree
+fetch:  somelib
+```
+
+Format: one rule per line, `kind: value` (rename uses `old -> new`), `#`
+comments and blank lines ignored.
+
+### Dependency resolution + unknown deps
+
+Resolver is ported from sbo-batch-test (`resolve_target` / `_resolve_visit`,
+DFS topo sort + cycle detection, `installed_in_base` check). Runs on the host
+against the selected tree.
+
+After resolving and applying overrides, every dep must be accounted for:
+in base, in the tree, or covered by a `fetch:` rule. If a dep is none of
+those (and no rule covers it), the script **stops before building**, reports
+it as UNMET, and asks the user to add an override rule and rerun, or abort.
+Never silently skip or guess.
+
+### Confirmation
+
+Always print the final build order before building, with overrides marked
+(dropped / renamed / fetch). Then `Y/n` to proceed. `--yes` skips the prompt
+for non-interactive/agent runs but STILL prints the order first.
+
+`--dry-run` resolves, applies overrides, prints the order, and exits without
+building (no confirm).
+
+### Build in container (ported from build_one)
+
+Deps then target, in order. For each package, inside the container:
+
+1. download sources (arch-specific `DOWNLOAD_x86_64`/`MD5SUM_x86_64` when
+   present, else `DOWNLOAD`/`MD5SUM`)
+2. verify md5
+3. `bash <pkg>.SlackBuild` with `OUTPUT` forced to a known dir
+4. `installpkg` the resulting `.txz`
+5. write a status token read back by the host
+
+`fetch:` deps (removed from the -current tree) are pulled via the baked-in
+`sbopkg`, which points at the image's matching SBo repo; everything else
+builds from the mounted local tree. Start light: handle only the few known
+`fetch:` cases, add rules as real packages need them.
+
+### Dependency cache
+
+Ported from sbo-batch-tester (`cache_decision`/`cache_path`/`cache_store`/
+`version_of`). A host dir caches built dep packages so consecutive runs reuse
+them instead of rebuilding the whole tree.
+
+- Config `PKG_CACHE=/path` enables it; empty (default) disables. `--no-cache`
+  forces a full rebuild for one run.
+- Bind-mounted read-only into the container; a cached dep is `installpkg`ed
+  instead of built (status `CACHED`). Storing is host-side: a freshly built
+  package is written to `OUTPUT` (a mounted dir the host reads back), and the
+  host copies it into the cache after the build (`cache_store`), so the cache
+  mount stays read-only. The **target always builds fresh** and refreshes its
+  own cache entry; it is never `CACHED`.
+- Key = prog + version (build/arch/tag ignored). Layout mirrors the SBo tree:
+  `$PKG_CACHE/<image-digest>/<category>/<prog>/<prog>-<ver>-...txz`, one .txz
+  per prog.
+- **Invalidation by image digest.** The cache is namespaced by the running
+  image's digest. When the digest changes (image updated by the nightly job),
+  the old namespace is stale: its deps were built against the previous image,
+  so they are ignored and rebuilt once under the new digest. This also keeps
+  the `:current` and `:15.0` caches separate (different images, different
+  digests). Old digest namespaces can be pruned.
+- A per-dep version bump (`bump: OLD -> NEW`) rebuilds and re-caches that dep.
+- Build-order line shows the outcome per dep: `cached (1.1)`,
+  `rebuild: 1.0 -> 1.1`, or `build (new)`; `--dry-run` shows the same without
+  building.
+
+### Target lint
+
+After the target builds, run `sbopkglint` on its `.txz` (tool baked into the
+image). Fail-soft: findings reported but do not change SUCCESS; missing tool
+prints a skip note. Target only (deps are vetted).
+
+### Report
+
+Per-package status + a color summary (screen) and a plain-text log under
+`LOG_ROOT/<timestamp>/`:
+
+```
+<timestamp>/
+  <prog>.log          per-package full build/install output
+  summary.log         plain recap
+  build-order.txt     the resolved+overridden order actually used
+```
+
+Status values (from sbo-batch-test):
+`SUCCESS CACHED DOWNLOAD-FAILED MD5-MISMATCH BUILD-FAILED INSTALL-FAILED
+BLOCKED-BY-DEP UNMET-DEP`. `CACHED` = a dep installed from the cache instead
+of rebuilt (target is never CACHED). `%README%` deps flagged as a reminder,
+not built.
+
+A fully green run tells the user it is safe to make the SBo submission tarball
+on the host (the container is no longer needed).
+
+## Options (planned)
+
+| Option | Effect |
+|--------|--------|
+| `--stable` / `15.0` | Target 15.0 (image + tree). Default is -current. |
+| `--dry-run` | Resolve + apply overrides + print order, no build. |
+| `--yes` | Skip the Y/n confirm (still prints the order). |
+| `--no-cache` | Rebuild all deps this run, ignore/refresh the cache. |
+| `--no-color` | Disable ANSI (auto-off when not a TTY). |
+| `-h`, `--help` | Usage. |
+
+## Self-check
+
+A `test-logic.sh` (host, no docker) covering the pure logic:
+
+- dep topo order + cycle detection (ported tests from sbo-batch-test)
+- override application: drop removes, rename maps, fetch marks source
+- unknown-dep -> UNMET stop
+- BLOCKED-BY-DEP propagation
+- cache decision: `cached`/`rebuild: OLD -> NEW`/`build (new)`, digest
+  namespacing, version-bump eviction (ported from sbo-batch-tester's tests)
+
+Docker/build/installpkg paths are out of the self-check's reach (verified by
+running a real target), same boundary as sbo-batch-test.
+
+## Resolved decisions
+
+- **Image**: a ready FULL-install image per version (full pkg set +
+  `sbo-maintainer-tools` + `sbopkg` on that version's repo), built by a
+  separate nightly job, NOT by this script. Script consumes it by tag.
+- **Missing image**: error clearly, point at the image-builder job. A local
+  registry `docker pull` slots in later via the same tag, no script change.
+- **`fetch:`**: via the image's `sbopkg` (per-version repo). Start with only
+  the few known cases; grow the override rules as needed.
+- **Script location**: `.extras/` (a tool, not a package).
+
+## Out of scope / later
+
+- The nightly image-builder (full-install + tools + sbopkg per version, NAS
+  storage, local registry). Its own tool, specced when the LAN machine is set
+  up.
+- Local registry pull step in this script (slots into the same config tag).
+```
+