deepseek-kubernetes-sandbox/docs/main-image.md

The main DSH Web image

This repository's primary artifact is a container image that packages DeepSeek Harness Web (dsh web) for Kubernetes and plain Docker. The Dockerfile at the repository root builds it; every version pin it uses lives in versions.env.

The image is image-first: it is the product, and the examples under examples/ are self-contained implementations that consume it.

What the build does

The Dockerfile is a two-stage build:

1. Build stage (node:24-trixie) clones DSH at the pinned git ref, installs dependencies with pnpm, runs the production build, packages the @deepseek-ai/dsh CLI with pnpm pack, and installs its production dependencies with npm.
2. Runtime stage (node:24-trixie-slim) copies /opt/dsh to /app, adds the CLI tools DSH agents commonly use (git, ripgrep, jq, yq, curl, wget, gh, tini, uv), and starts dsh web through a small entrypoint.

Build it

make image          # canonical: builds the DSH Web image, no push

make image reads versions.env and passes the pins as build args. To reproduce the equivalent by hand:

docker build \
  --build-arg DSH_VERSION=dsh-v0.2.1-rc.2 \
  --build-arg RELEASE_REVISION=r2 \
  --build-arg PNPM_VERSION=11.28.5 \
  --build-arg VCS_REF="$(git rev-parse --short HEAD)" \
  -t ghcr.io/sredevopsorg/deepseek-kubernetes-sandbox:dsh-v0.2.1-rc.2-r2 .

Build args

Arg	Default / source	Purpose
DSH_REPO	https://github.com/deepseek-ai/deepseek-harness.git	Upstream DSH repository to clone.
DSH_VERSION	DSH_VERSION in versions.env	Upstream DSH git tag/ref to package; recorded as org.opencontainers.image.version.
RELEASE_REVISION	RELEASE_REVISION in versions.env	Repository revision suffix (rN); the release identity is DSH_VERSION-RELEASE_REVISION, recorded in the io.sredevopsorg.release.revision label. See versioning.
PNPM_VERSION	PNPM_VERSION in versions.env	pnpm version activated with corepack in both stages.
VCS_REF	git rev-parse --short HEAD (via make image)	Source revision recorded for traceability.
NODE_BUILD_IMAGE	docker.io/node:24-trixie	Build-stage base image.
NODE_RUNTIME_IMAGE	docker.io/node:24-trixie-slim	Runtime-stage base image.

Never hard-code a version outside versions.env: ./scripts/check-versions.sh (and make check) fails when a pin drifts.

Runtime contract

Entrypoint

The entrypoint is tini -- /usr/local/bin/dsh-entrypoint:

1. tini runs as PID 1 and reaps children/forwards signals.
2. The shell entrypoint applies defaults, derives a bind address when DSH_HOST is empty (the pod/container's first non-loopback IPv4), builds the dsh web command line, and execs it so signals reach the Node process.
3. localhost and 127.0.0.1 are always added to DSH's trusted-host list; each DSH_TRUSTED_HOSTS entry is added as an extra --trusted-host.

Environment variables

Variable	Default	Purpose
DSH_PORT	3080	Port DSH Web listens on inside the container.
DSH_HOST	auto-detected non-loopback IPv4	Bind address. Leave empty in Kubernetes so the pod IP is used automatically.
DSH_PUBLIC_URL	http://localhost:${DSH_PORT}	Public base URL used to build links and the launch-token URL printed in the logs. Set it when the container is published on a different host port or behind a proxy.
DSH_TRUSTED_HOSTS	empty	Extra Host/Origin allow-list entries, comma- or space-separated. localhost/127.0.0.1 are always trusted. Required when a proxy forwards the browser's Host.
DEEPSEEK_API_KEY	empty	Provider credential read by DSH. Inject it with -e/envFrom; never bake it into the image. Only model calls fail when it is missing.
DSH_HOME	/home/node/.dsh	DSH state directory (conversations, sessions, config, credentials). Mount a volume here to persist it.

The image also sets NODE_ENV=production, HOME=/home/node, and a PATH that includes /app/node_modules/.bin.

Ports, volumes and signals

Item	Value	Notes
Exposed port	3080/tcp	EXPOSE 3080; one port serves the UI, assets, API, SSE and WebSocket traffic.
State volume	/home/node/.dsh	Declared with VOLUME; use a named volume (Docker) or PVC (Kubernetes).
Working directory	/workspace	The agent workspace; mount a volume here if agents should keep files.
Stop signal	SIGTERM	tini forwards it to dsh web; allow a graceful shutdown period.
User	node, UID/GID 1000	The process is non-root. A PVC mounted at DSH_HOME must be writable by UID 1000.

Health probes

/ is not a health endpoint: DSH returns 401 until a browser completes the launch-token handshake. Probe /favicon.svg instead — it is unauthenticated and served by the web layer, so it proves the HTTP server is up without triggering auth.

startupProbe:
  httpGet: {path: /favicon.svg, port: 3080}
  periodSeconds: 5
  failureThreshold: 24
readinessProbe:
  httpGet: {path: /favicon.svg, port: 3080}
  periodSeconds: 5
livenessProbe:
  httpGet: {path: /favicon.svg, port: 3080}
  periodSeconds: 15

The shipped templates use exactly this shape; see examples/minimal-single-tenant/manifests/sandbox-template.yaml. A startupProbe is important because plugin activation (or the first start of a large sandbox) can exceed a default liveness budget.

Launch token

DSH prints its one-time launch URL to the logs:

dsh web: http://<host>:${DSH_PORT}/?token=...

Open that URL once to obtain DSH's auth cookie. After that the UI works at the bare URL; without the cookie / answers 401 by design. The agents-as-a-service gateway performs this handshake server-side so browsers never see the token.

Published image names and tags

Registry layout: the main image is the repository itself, and every example component is a nested package below it:

ghcr.io/sredevopsorg/deepseek-kubernetes-sandbox                        # main DSH Web image
ghcr.io/sredevopsorg/deepseek-kubernetes-sandbox/dsh-agents-as-a-service/gateway   # example component

The main image is published multi-arch (linux/amd64, linux/arm64) to GitHub Container Registry:

Tag	Meaning
dsh-v0.2.1-rc.2-r2	Current release identity. Immutable: once published it never moves.
latest	Most recent release; points at the same digest as the current identity.
main	Development channel rebuilt from every push to main; not a release, not for production.
dsh-v0.2.1-rc.2	Legacy tag published before the release-identity scheme existed. Do not use it for new deployments; see the migration table in the root README.

Release identities, channels and rollback rules are defined in versioning. Tags are immutable, so production deployments should pin a digest:

docker buildx imagetools inspect ghcr.io/sredevopsorg/deepseek-kubernetes-sandbox:dsh-v0.2.1-rc.2-r2
# ... pin the digest in your deployment manifests:
#   image: ghcr.io/sredevopsorg/deepseek-kubernetes-sandbox@sha256:<digest>

Verifying an image

docker inspect ghcr.io/sredevopsorg/deepseek-kubernetes-sandbox:dsh-v0.2.1-rc.2-r2 \
  --format '{{json .Config.Labels}}'
# org.opencontainers.image.title / .version / .source

Release builds also publish SBOM and provenance attestations from the release workflow (see SECURITY.md and gitflow).