chore: use dynamic port for heroku

Author: Manuel Rauber

backend/src/servers/http-server.ts

@@ -30,7 +30,7 @@ export class HttpServer {
   }
 
   listen(): void {
-    // TODO: dynamic port
-    this.server.listen(8080, () => debug('Server is up and running on port %s', 8080));
+    const port = process.env.PORT || 8080;
+    this.server.listen(port, () => debug('Server is up and running on port %s', port));
   }
 }

frontend/Dockerfile

@@ -20,4 +20,6 @@ FROM nginx:alpine
 WORKDIR /app
 
 COPY --from=build-env /app/dist/smudgy /usr/share/nginx/html
-COPY --from=build-env /app/config/nginx.conf /etc/nginx/conf.d/default.conf
+COPY --from=build-env /app/config/nginx.conf /etc/nginx/conf.d/default.template
+
+CMD sh -c "envsubst \"`env | awk -F = '{printf \" \\\\$%s\", $1}'`\" < /etc/nginx/conf.d/default.template > /etc/nginx/conf.d/default.conf && nginx -g 'daemon off;'"

frontend/config/nginx.conf

@@ -1,5 +1,5 @@
 server {
-  listen 80;
+  listen ${NGINX_PORT};
 
   # add mime types if needed:
   include mime.types;