fix(docz-core): parse port when running serve

core/docz-core/src/cli.ts

@@ -19,9 +19,9 @@ export const cli = () => {
       await commands.build(args)
       process.exit()
     })
-    .command('serve', 'serve dir as static site', setArgs, async () => {
+    .command('serve', 'serve dir as static site', setArgs, async args => {
       setEnv('production')
-      await commands.serve()
+      await commands.serve(args)
       process.exit()
     })
     .demandCommand()

core/docz-core/src/commands/serve.ts

@@ -1,10 +1,22 @@
 import sh from 'shelljs'
+import { Arguments } from 'yargs'
 
 import * as paths from '../config/paths'
 import { spawnSync } from '../utils/spawn'
+import { parseConfig } from '../config/docz'
 
-export const serve = async () => {
+export const serve = async (args: Arguments<any>) => {
+  const config = await parseConfig(args)
   const cliArgs = ['run', 'serve']
+
+  if (config.port) {
+    cliArgs.push('--')
+    // Append gatsby option `port`to CLI args
+    // https://www.gatsbyjs.org/docs/cheat-sheet/#cheat_sheet-text
+    cliArgs.push('--port')
+    cliArgs.push(String(config.port))
+  }
+
   sh.cd(paths.docz)
   spawnSync('npm', cliArgs)
 }