Diogramos

A collaborative diagram & canvas editor. Draw shapes and connectors on a canvas, hand out edit access by link, or drop a read-only embed into another site. Phoenix LiveView on top of PostgreSQL, with live multi-user editing.

Features

• Canvas editor — shapes and connectors with anchor-aware routing, edited live at /c/:slug (Phoenix LiveView). Open boards from /canvases.
• Metadata links — attach external (https://…) or canvas-to-canvas links to an element; they render as side-by-side icons on the shape.
• Folders & organization — group canvases into folders. Deleting a canvas is owner-only and asks for its slug to be typed back first.
• Sharing & permissions — role-based grants per folder/canvas, plus one-off share links (/s/:token).
• Embeds — publish a canvas read-only via /embed/:token (and the /c-embed/:slug redirect for in-canvas links). Add ?mode=frame for a static framing — no live cursors or identity chip, diagram scaled to fill the iframe — suited to slides and docs. ?theme=<name> picks the palette; the embedding page can also switch it live by posting {type: "diogramos:set-theme", theme} to the iframe, which announces {type: "diogramos:ready"} to its parent once it’s listening.
• JSON export — /c/:slug/export.json for any canvas you can see.
• Accounts — magic-link login by default, password optional, with invite-gated registration (/users/invites).
• Themes — pick a daisyUI theme; the choice persists.

Quick start

# 1. Bring up Postgres (see compose.yml)
podman compose up -d   # or: docker compose up -d

# 2. Install deps, create + migrate the dev DB, build assets
mix setup

# 3. Start the dev server
mix phx.server

Then open http://localhost:4000. Registration is invite-only by default — mint a link from /users/invites, or seed an initial confirmed user:

mix run -e 'Diogramos.Release.init("you@example.com", "a strong password")'

Container images

CI publishes a multi-registry image on every push to master:

• the forge’s own registry, $CI_REGISTRY/neiam/diogramos, when the repository is hosted on one that sets CI_REGISTRY
• ghcr.io/neiam/diogramos
• docker.io/neiam/diogramos
• quay.io/neiam/diogramos

Tags: latest (default branch), vX.Y.Z + X.Y (git tags), the branch name, and the commit SHA.

The forge registry is the one that needs no setup: the per-job github.token is already authorized to push to that repository’s own image path and nowhere else, so there is no secret to create. The three public registries need GHCR_TOKEN, DOCKERHUB_USER/DOCKERHUB_TOKEN and QUAY_USERNAME/QUAY_TOKEN; each login is skipped on pull requests, and a missing CI_REGISTRY simply drops the forge registry from the list.

docker pull ghcr.io/neiam/diogramos:latest

docker run --rm -p 4000:4000 \
  -e PHX_SERVER=true \
  -e SECRET_KEY_BASE="$(openssl rand -base64 48)" \
  -e PHX_HOST=localhost \
  -e POSTGRES_HOST=host.containers.internal \
  -e POSTGRES_USER=postgres -e POSTGRES_PASSWORD=postgres -e POSTGRES_DB=diogramos \
  ghcr.io/neiam/diogramos:latest

Or set DATABASE_URL=ecto://user:pass@host/db instead of the discrete POSTGRES_* variables.

Tests

mix test
mix precommit   # compile --warnings-as-errors, deps.unlock --unused, format, test

mix precommit is what CI runs and what every change should pass.