Makefile:
- dry-run target (default) shows registry, branch, SHA, version, all computed
image tags, and build args — no side effects
- build/push/release targets wire docker build and docker push
- Branch-aware tag strategy:
main → <version> + latest
develop → <version>-dev-<short-sha>
release/* → <version>-qa-<short-sha>
- Version resolved from the highest semver tag at HEAD; falls back to the most
recent reachable tag via git describe
- BASE_DIGEST resolved at build time from the local Docker daemon; dry-run
prints a hint when the base image is not yet pulled
- Note: case/esac cannot be used inside $(shell) — Make's parser matches the
pattern ")" as the function's closing paren before the shell sees it;
if/elif/else/fi used instead
Dockerfile:
- OCI standard labels added to the final stage via build args (VERSION, GIT_SHA,
BASE_DIGEST):
org.opencontainers.image.source — repo URL
org.opencontainers.image.version — semver tag
org.opencontainers.image.revision — git commit SHA
org.opencontainers.image.base.name — alpine:3.21
org.opencontainers.image.base.digest — digest of base image at build time
- Custom label:
dev.nochebuena.healthz — /health
einherjar/spa-server
A shield wall holds because every warrior knows their position. The SPA asks only for the wall — not for every soldier's name.
code.nochebuena.dev/einherjar/spa-server is a container-first HTTP server for single-page applications and progressive web apps. It serves static assets directly and falls back to index.html for any path that does not resolve to a file on disk — the standard SPA routing contract.
The module ships as a ready-to-use Docker base image. Deploying a SPA to a container requires a single COPY instruction. No nginx, no custom configuration, no index.html redirect logic to maintain.
Container usage
FROM code.nochebuena.dev/einherjar/spa-server:v1.0.0
COPY dist/ /srv/www/
That is the complete Dockerfile for a production SPA container.
Environment variables
| Variable | Default | Description |
|---|---|---|
EINHERJAR_SPA_PORT |
8080 |
TCP port the server listens on |
EINHERJAR_SPA_STATIC_DIR |
/srv/www |
Path to the directory containing index.html and assets |
EINHERJAR_LOG_LEVEL |
INFO |
Log level: DEBUG, INFO, WARN, ERROR |
Health endpoint
GET /health returns 200 OK with a JSON body consistent with all Einherjar health responses:
{"status":"UP","components":{}}
503 Service Unavailable is never returned — if the process is alive, it is healthy. Wire /health directly to your container liveness and readiness probes.
Routing behaviour
| Request | Result |
|---|---|
/app.js — file exists |
Served directly with correct Content-Type |
/assets/logo.png — file exists |
Served directly |
/dashboard — no matching file |
index.html served (SPA router handles it) |
/ — directory |
index.html served (directory listing is disabled) |
Dependency graph
contracts (zero dependencies)
↑
core
↑
spa-server (contracts, core, stdlib only)
No external dependencies beyond the Go standard library.
Verification
cd spa-server/
go build ./...
go vet ./...
go test ./...
gofmt -l .
A shield wall holds because every warrior knows their position. The SPA asks only for the wall — not for every soldier's name.