Extract REPL impl. to lib (#94)

* Extract REPL impl. to lib

* Define and implement generic REPLConfig

Author: jeferson-sb

src/_boot/repl.ts

@@ -1,98 +1,19 @@
-import REPL, { REPLEval, ReplOptions, REPLServer } from 'repl';
-import vm from 'vm';
-import { createServer, Server } from 'net';
 import { makeModule } from '@/context';
+import { makeREPL, REPLConfigType } from '@/_lib/repl';
 
-type REPLConfig = {
-  appName: string;
-  cli: boolean;
-  repl: {
-    port: number;
-  };
-};
-
-const repl = makeModule(
-  'repl',
-  async ({
-    app: { onReady, terminate },
-    container,
-    config: {
-      appName,
-      cli,
-      environment,
-      repl: { port },
-    },
-    logger,
-  }) => {
-    const promisableEval: REPLEval = (cmd, context, filename, callback) => {
-      const result = vm.runInContext(cmd, context);
-
-      if (isPromise(result)) {
-        return result.then((v) => callback(null, v)).catch((e) => callback(e, null));
-      }
-
-      return callback(null, result);
-    };
-
-    const isPromise = (value) => value && typeof value.then === 'function' && typeof value.catch === 'function';
-
-    const createREPL = (
-      config: Partial<ReplOptions> = { input: process.stdin, output: process.stdout }
-    ): REPLServer => {
-      const repl = REPL.start({
-        eval: promisableEval,
-        prompt: `${appName}$ `,
-        ignoreUndefined: true,
-        ...config,
-      });
-
-      Object.assign(repl.context, { registry: container.cradle, container });
+type REPLConfig = REPLConfigType<{ appName: string; cli: boolean; repl: { port: number } }>;
 
-      return repl;
-    };
+const repl = makeModule('repl', async ({ app: { onReady, terminate }, container, config, logger }) => {
+  const repl = makeREPL({ container, config, logger });
 
-    let server: Server;
+  onReady(async () => {
+    await repl.start({ terminate });
+  });
 
-    const startREPL = async () => {
-      if (cli) {
-        const repl = createREPL();
-
-        repl.on('close', terminate);
-      } else if (!['production', 'test'].includes(environment)) {
-        server = createServer((socket) => {
-          const repl = createREPL({
-            input: socket,
-            output: socket,
-            terminal: true,
-          });
-
-          repl.on('close', () => {
-            socket.end();
-          });
-
-          socket.on('error', (err) => {
-            logger.error('[REPL] Connection error');
-            logger.error(err);
-            socket.end();
-          });
-        }).listen(port);
-      }
-    };
-
-    onReady(startREPL);
-
-    return async () => {
-      if (server && server.listening) {
-        await new Promise<void>((resolve, reject) =>
-          server.close((err) => {
-            if (err) return reject(err);
-            resolve();
-          })
-        );
-      }
-    };
-  }
-);
+  return async () => {
+    await repl.close();
+  };
+});
 
 export { repl };
 export type { REPLConfig };

src/_lib/repl/index.ts

@@ -0,0 +1,107 @@
+import REPL, { REPLEval, ReplOptions, REPLServer } from 'repl';
+import vm from 'vm';
+import { createServer, Server } from 'net';
+import { AwilixContainer } from 'awilix';
+import { Logger } from 'pino';
+import { EnvironmentConfig } from '../Environment';
+
+type REPLConfigType<T> = {
+  [key in keyof T]: T[key];
+};
+
+type ReplParameters = {
+  container: AwilixContainer;
+  config: REPLConfigType<{
+    appName: string;
+    cli: boolean;
+    repl: { port: number };
+    environment: EnvironmentConfig['environment'];
+  }>;
+  logger: Logger;
+};
+
+type REPL = {
+  create: (config: Partial<ReplOptions>) => REPLServer;
+  start: ({ terminate }) => Promise<void>;
+  close: () => Promise<void>;
+};
+
+const isPromise = (value) => value && typeof value.then === 'function' && typeof value.catch === 'function';
+
+const promisableEval: REPLEval = (cmd, context, filename, callback) => {
+  const result = vm.runInContext(cmd, context);
+
+  if (isPromise(result)) {
+    return result.then((v) => callback(null, v)).catch((e) => callback(e, null));
+  }
+
+  return callback(null, result);
+};
+
+const makeREPL = ({
+  container,
+  config: {
+    appName,
+    cli,
+    environment,
+    repl: { port },
+  },
+  logger,
+}: ReplParameters): REPL => {
+  let server: Server;
+
+  const create = (config: Partial<ReplOptions> = { input: process.stdin, output: process.stdout }): REPLServer => {
+    const repl = REPL.start({
+      eval: promisableEval,
+      prompt: `${appName}$ `,
+      ignoreUndefined: true,
+      ...config,
+    });
+
+    Object.assign(repl.context, { registry: container.cradle, container });
+
+    return repl;
+  };
+
+  return {
+    create,
+    start: async ({ terminate }) => {
+      if (cli) {
+        const repl = create();
+
+        repl.on('close', terminate);
+      } else if (!['production', 'test'].includes(environment)) {
+        server = createServer((socket) => {
+          const repl = create({
+            input: socket,
+            output: socket,
+            terminal: true,
+          });
+
+          repl.on('close', () => {
+            socket.end();
+          });
+
+          socket.on('error', (err) => {
+            logger.error('[REPL] Connection error');
+            logger.error(err);
+            socket.end();
+          });
+        }).listen(port);
+      }
+    },
+    close: async () => {
+      if (server && server.listening) {
+        await new Promise<void>((resolve, reject) =>
+          server.close((err) => {
+            if (err) return reject(err);
+            resolve();
+          })
+        );
+      }
+    },
+  };
+};
+
+export { makeREPL };
+export type { REPLConfigType };