feat: update Dockerfile for GitHub Packages authentication with NPM_TOKEN and enhance README instructions

Author: Thavarshan

Dockerfile

@@ -10,11 +10,21 @@ WORKDIR /app
 
 # Copy package files
 COPY package*.json ./
+COPY .npmrc ./
 COPY prisma ./prisma/
 
+# Configure npm authentication for private @auralyze/engine package from GitHub Packages
+# NPM_TOKEN must be set as a Railway environment variable
+ARG NPM_TOKEN
+RUN echo "//npm.pkg.github.com/:_authToken=${NPM_TOKEN}" >> ~/.npmrc
+
 # Install all dependencies (including dev dependencies for build)
+# This will authenticate with GitHub Packages using the token above
 RUN npm ci
 
+# Remove npmrc files after install for security
+RUN rm -f ~/.npmrc .npmrc
+
 # Generate Prisma Client (critical step!)
 RUN npx prisma generate
 

README.md

@@ -122,12 +122,14 @@ Response: `EngineState` from `@auralyze/engine` with all analysis results. Inclu
 Build the API service for Railway deployment:
 
 ```bash
-docker build -t auralyze-api .
+# Build with npm token for private @auralyze/engine package
+docker build --build-arg NPM_TOKEN=$NPM_TOKEN -t auralyze-api .
 docker run -p 8080:8080 --env-file .env auralyze-api
 ```
 
 The Dockerfile handles:
 
+- **GitHub Packages Authentication**: Requires `NPM_TOKEN` build arg to install private `@auralyze/engine` package
 - **Prisma Client Generation**: Runs `npx prisma generate` during build
 - **Database Migrations**: Runs `npm run db:deploy` on container start
 - **TypeScript Compilation**: Builds to `dist/` directory
@@ -136,11 +138,12 @@ The Dockerfile handles:
 When deploying to Railway as a standalone repository:
 
 1. Ensure `Dockerfile` exists in repo root (Railway auto-detects it)
-2. Add database reference: `DATABASE_URL=${{Postgres.DATABASE_URL}}`
-3. Configure service references for internal networking:
+2. **Set `NPM_TOKEN` environment variable** in Railway with your GitHub Personal Access Token (with `read:packages` scope)
+3. Add database reference: `DATABASE_URL=${{Postgres.DATABASE_URL}}`
+4. Configure service references for internal networking:
    - `METADATA_SERVICE_URL=https://metadata.railway.internal`
    - `ANALYSIS_SERVICE_URL=https://analysis.railway.internal`
-4. Generate and set API keys for service authentication
+5. Generate and set API keys for service authentication
 
 The Dockerfile ensures Prisma Client is generated **before** runtime, preventing `@prisma/client did not initialize` errors.
 :::