'yarn rw dev' now only starts the API and DB servers when the api fol…

…der is present

packages/cli/src/commands/dev.js

@@ -1,3 +1,4 @@
+import fs from 'fs'
 import path from 'path'
 
 import concurrently from 'concurrently'
@@ -16,15 +17,17 @@ export const handler = async ({ app = ['db', 'api', 'web'] }) => {
   // For Windows: Replaces ` ` with `\ `. Damn, there has got to be a better
   // way to sanitize paths?!
   const BASE_DIR = getPaths().base.replace(' ', '\\ ')
+  const API_DIR = path.join(BASE_DIR, 'api')
 
   // Generate the Prisma client if it doesn't exist.
   await generatePrismaClient({ verbose: false, force: false })
 
   const jobs = {
     api: {
       name: 'api',
-      command: `cd ${path.join(BASE_DIR, 'api')} && yarn dev-server`,
+      command: `cd ${API_DIR} && yarn dev-server`,
       prefixColor: 'cyan',
+      runWhen: () => fs.existsSync(API_DIR),
     },
     db: {
       name: ' db', // prefixed with ` ` to match output indentation.
@@ -33,6 +36,7 @@ export const handler = async ({ app = ['db', 'api', 'web'] }) => {
         'api'
       )} && yarn prisma generate --watch`,
       prefixColor: 'magenta',
+      runWhen: () => fs.existsSync(API_DIR),
     },
     web: {
       name: 'web',
@@ -41,13 +45,14 @@ export const handler = async ({ app = ['db', 'api', 'web'] }) => {
         'web'
       )} && yarn webpack-dev-server --config ../node_modules/@redwoodjs/core/config/webpack.development.js`,
       prefixColor: 'blue',
+      runWhen: () => true,
     },
   }
 
   concurrently(
     Object.keys(jobs)
       .map((n) => app.includes(n) && jobs[n])
-      .filter(Boolean),
+      .filter((job) => job.runWhen()),
     {
       restartTries: 3,
       prefix: '{time} {name} |',