fix: make prisma provider configurable by env DATABASE_PROVIDER (#71)

README.md

@@ -217,7 +217,7 @@ Why:
 
 | Area          | Limitation                                                                                                                                                                                                                                                                                        |
 | ------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
-| Database      | The backend uses a local **SQLite file** database by default (`DATABASE_URL=file:/.../dev.db`). Running multiple backend replicas either creates split-brain state (separate DB files/volumes) or requires sharing a single SQLite file across hosts, which is not a reliable deployment pattern. |
+| Database      | The backend uses **SQLite** by default. For production deployments requiring high availability, use **PostgreSQL** (`DATABASE_PROVIDER=postgresql`). SQLite still works for single-instance deployments but is not recommended for multi-replica setups. |
 | Collaboration | Real-time presence state is tracked **in-memory** in the backend process, so multiple replicas will fragment presence/collaboration unless a shared Socket.IO adapter is added.                                                                                                                   |
 
 Recommended deployment pattern:
@@ -336,14 +336,73 @@ docker compose -f docker-compose.oidc.yml down
 
 Base values are documented in `backend/.env.example`. Common ones to care about:
 
-| Variable       | Default / Example         | Description                                                                         |
-| -------------- | ------------------------- | ----------------------------------------------------------------------------------- |
-| `DATABASE_URL` | `file:/app/prisma/dev.db` | SQLite file or external DB URL.                                                     |
-| `FRONTEND_URL` | `http://localhost:6767`   | Allowed frontend origin(s), comma-separated for multiple entries.                   |
-| `TRUST_PROXY`  | `false`                   | `false`, `true`, or hop count (for example `1`).                                    |
-| `JWT_SECRET`   | `change-this-secret...`   | Recommended in production so sessions remain stable across restarts and migrations. |
-| `CSRF_SECRET`  | `change-this-secret`      | Recommended in production so CSRF validation remains stable across restarts.        |
-| `AUTH_MODE`    | `local`                   | `local`, `hybrid`, `oidc_enforced`.                                                 |
+| Variable            | Default / Example         | Description                                                                         |
+| ------------------- | ------------------------- | ----------------------------------------------------------------------------------- |
+| `DATABASE_PROVIDER` | `sqlite`                 | Database provider: `sqlite` or `postgresql`. See [Database Provider](#database-provider) for details. |
+| `DATABASE_URL`      | `file:/app/prisma/dev.db` | SQLite file or external DB URL.                                                     |
+| `FRONTEND_URL`      | `http://localhost:6767`   | Allowed frontend origin(s), comma-separated for multiple entries.                   |
+| `TRUST_PROXY`       | `false`                   | `false`, `true`, or hop count (for example `1`).                                    |
+| `JWT_SECRET`        | `change-this-secret...`   | Recommended in production so sessions remain stable across restarts and migrations. |
+| `CSRF_SECRET`       | `change-this-secret`      | Recommended in production so CSRF validation remains stable across restarts.        |
+| `AUTH_MODE`         | `local`                   | `local`, `hybrid`, `oidc_enforced`.                                                 |
+
+</details>
+
+<details>
+<summary>Database Provider</summary>
+
+## Database Provider
+
+ExcaliDash supports both **SQLite** (default) and **PostgreSQL** as database providers. The provider is controlled by the `DATABASE_PROVIDER` environment variable.
+
+### SQLite (Default)
+
+SQLite is the default and works out of the box without additional configuration:
+
+```yaml
+# docker-compose.prod.yml
+services:
+  backend:
+    environment:
+      - DATABASE_PROVIDER=sqlite
+      - DATABASE_URL=file:/app/prisma/dev.db
+```
+
+### PostgreSQL
+
+To use PostgreSQL instead of SQLite:
+
+1. **Set the environment variables:**
+
+```yaml
+# docker-compose.prod.yml
+services:
+  backend:
+    environment:
+      - DATABASE_PROVIDER=postgresql
+      - DATABASE_URL=postgresql://user:password@host:5432/excalidash
+```
+
+2. **Generate PostgreSQL migrations:**
+
+The repository includes SQLite migrations by default. To use PostgreSQL, you need to generate migrations for the PostgreSQL provider:
+
+```bash
+# 1. Set the provider in your local environment
+export DATABASE_PROVIDER=postgresql
+export DATABASE_URL="postgresql://user:password@localhost:5432/excalidash"
+
+# 2. Remove existing SQLite migrations
+rm -rf backend/prisma/migrations/postgresql
+
+# 3. Generate initial migration for PostgreSQL
+cd backend
+npx prisma migrate dev --name init
+```
+
+This creates a new `backend/prisma/migrations/postgresql/` folder with PostgreSQL-specific migrations.
+
+**Note:** When switching database providers, you cannot migrate existing data. The new database will start empty.
 
 </details>
 

backend/.env.example

@@ -1,6 +1,8 @@
 # Backend Environment Variables
 PORT=8000
 NODE_ENV=production
+# Database provider: sqlite or postgresql
+DATABASE_PROVIDER=sqlite
 DATABASE_URL=file:/app/prisma/dev.db
 FRONTEND_URL=http://localhost:6767
 # Keep disabled unless traffic always comes through a trusted reverse proxy.

backend/Dockerfile

@@ -16,7 +16,11 @@ RUN npm ci && npm cache clean --force
 # Copy prisma schema
 COPY prisma ./prisma/
 
-# Generate Prisma Client
+# Set default provider for build-time Prisma generation (runtime can override via DATABASE_PROVIDER)
+RUN sed -i 's/provider = env("[^"]*")/provider = "sqlite"/' prisma/schema.prisma
+
+# Generate Prisma Client at build time (for TypeScript compilation)
+# Runtime will regenerate if DATABASE_PROVIDER differs
 RUN npx prisma generate
 
 # Copy source code
@@ -51,7 +55,7 @@ COPY prisma ./prisma_template/
 # Copy built application from builder
 COPY --from=builder /app/dist ./dist
 
-# Copy the generated Prisma Client from builder to maintain the same structure
+# Copy the generated Prisma Client from builder (will be regenerated at runtime if provider changes)
 COPY --from=builder /app/src/generated ./dist/generated
 
 # Create necessary directories (ownership will be set in entrypoint)

backend/docker-entrypoint.sh

@@ -50,25 +50,47 @@ fi
 
 export CSRF_SECRET
 
-# 1. Ensure schema and migrations are present (Running as root)
-# Never copy the entire prisma directory, as that can unintentionally overwrite
-# persisted SQLite files or copy stray *.db artifacts into the volume.
-if [ ! -f "/app/prisma/schema.prisma" ]; then
-    echo "Mount appears empty (missing schema.prisma). Bootstrapping schema and migrations..."
-else
-    # Volume exists but may be missing new migrations from an upgrade.
-    echo "Syncing schema and migrations from template..."
+# Set default DATABASE_PROVIDER if not set
+if [ -z "${DATABASE_PROVIDER:-}" ]; then
+    echo "DATABASE_PROVIDER not set, defaulting to sqlite"
+    DATABASE_PROVIDER="sqlite"
+fi
+
+# Validate DATABASE_PROVIDER
+if [ "${DATABASE_PROVIDER}" != "sqlite" ] && [ "${DATABASE_PROVIDER}" != "postgresql" ]; then
+    echo "ERROR: DATABASE_PROVIDER must be 'sqlite' or 'postgresql', got '${DATABASE_PROVIDER}'"
+    exit 1
 fi
 
+# Ensure migrations directory exists
 mkdir -p /app/prisma/migrations
+
+# Copy schema.prisma from template
 cp /app/prisma_template/schema.prisma /app/prisma/schema.prisma
-cp -R /app/prisma_template/migrations/. /app/prisma/migrations/
+
+# Clear and copy provider-specific migrations folder
+echo "Copying ${DATABASE_PROVIDER} migrations..."
+rm -rf /app/prisma/migrations/*
+cp -R /app/prisma_template/migrations/"${DATABASE_PROVIDER}"/. /app/prisma/migrations/
+
+# Update schema.prisma with the runtime provider (handles both env() and static values)
+echo "Configuring Prisma for provider: ${DATABASE_PROVIDER}"
+sed -i 's/provider = env("[^"]*")/provider = "'"${DATABASE_PROVIDER}"'"/' /app/prisma/schema.prisma
+sed -i 's/provider = "[^"]*"/provider = "'"${DATABASE_PROVIDER}"'"/' /app/prisma/schema.prisma
+
+# Generate Prisma Client at runtime (run as root since schema is owned by root)
+echo "Generating Prisma Client..."
+npx prisma generate --schema=/app/prisma/schema.prisma
+
+# Copy generated client to the expected location for the application
+mkdir -p /app/dist/generated
+cp -r /app/src/generated/* /app/dist/generated/
 
 # 2. Fix permissions unconditionally (Running as root)
 echo "Fixing filesystem permissions..."
-chown -R nodejs:nodejs /app/uploads
-chown -R nodejs:nodejs /app/prisma
+chown -R nodejs:nodejs /app/uploads /app/prisma /app/dist/generated
 chmod 755 /app/uploads
+chmod -R 755 /app/dist/generated
 chmod 600 "${JWT_SECRET_FILE}"
 chmod 600 "${CSRF_SECRET_FILE}"