Add a Dockerfile for the cosmosdb-server service

Add a Dockerfile that uses Node.js 12.x to install the necessary project
dependencies to run cosmosdb-server within a container. In addition, add
support to the server itself to gracefully shutdown when given a subset
of UNIX signals (e.g., SIGINT, SIGTERM).

Author: hectcastro

.dockerignore

@@ -0,0 +1,2 @@
+Dockerfile
+node_modules

Dockerfile

@@ -0,0 +1,13 @@
+FROM node:12-slim
+
+WORKDIR /app
+
+COPY package.json yarn.lock ./
+
+RUN yarn install --production=false --frozen-lockfile 
+
+COPY . .
+
+RUN yarn run build
+
+ENTRYPOINT [ "node", "lib/cli.js" ] 

src/index.ts

@@ -87,5 +87,17 @@ export default (opts?: ServerOptions) => {
     }
   });
 
+  const gracefulShutdown = () => {
+    console.debug("Attempting a graceful shutdown...");
+
+    server.close(() => {
+      console.debug("Existing connections closed. Exiting...");
+      process.exit(0);
+    });
+  };
+
+  process.on('SIGINT', gracefulShutdown);
+  process.on('SIGTERM', gracefulShutdown);
+
   return server;
 };