Adding feature flagging, the option to only start the automations, or the API, meaning we can split the service if needed.

packages/server/src/app.ts

@@ -1,120 +1,41 @@
+import Sentry from "@sentry/node"
+
 if (process.env.DD_APM_ENABLED) {
   require("./ddApm")
 }
 
 // need to load environment first
 import env from "./environment"
-
-import { ExtendableContext } from "koa"
 import * as db from "./db"
 db.init()
-import Koa from "koa"
-import koaBody from "koa-body"
-import http from "http"
-import * as api from "./api"
-import * as automations from "./automations"
-import { Thread } from "./threads"
-import * as redis from "./utilities/redis"
 import { ServiceType } from "@budibase/types"
-import {
-  events,
-  logging,
-  middleware,
-  timers,
-  env as coreEnv,
-} from "@budibase/backend-core"
+import { env as coreEnv } from "@budibase/backend-core"
 coreEnv._set("SERVICE_TYPE", ServiceType.APPS)
+import { apiEnabled } from "./features"
+import createKoaApp from "./koa"
+import Koa from "koa"
+import { Server } from "http"
 import { startup } from "./startup"
-const Sentry = require("@sentry/node")
-const destroyable = require("server-destroy")
-const { userAgent } = require("koa-useragent")
 
-const app = new Koa()
+let app: Koa, server: Server
 
-let mbNumber = parseInt(env.HTTP_MB_LIMIT || "10")
-if (!mbNumber || isNaN(mbNumber)) {
-  mbNumber = 10
-}
-// set up top level koa middleware
-app.use(
-  koaBody({
-    multipart: true,
-    formLimit: `${mbNumber}mb`,
-    jsonLimit: `${mbNumber}mb`,
-    textLimit: `${mbNumber}mb`,
-    // @ts-ignore
-    enableTypes: ["json", "form", "text"],
-    parsedMethods: ["POST", "PUT", "PATCH", "DELETE"],
-  })
-)
-
-app.use(middleware.correlation)
-app.use(middleware.pino)
-app.use(userAgent)
-
-if (env.isProd()) {
+async function start() {
+  if (apiEnabled()) {
+    const koa = createKoaApp()
+    app = koa.app
+    server = koa.server
+  }
+  await startup(app, server)
+  if (env.isProd()) {
     env._set("NODE_ENV", "production")
     Sentry.init()
-
-  app.on("error", (err: any, ctx: ExtendableContext) => {
-    Sentry.withScope(function (scope: any) {
-      scope.addEventProcessor(function (event: any) {
-        return Sentry.Handlers.parseRequest(event, ctx.request)
-      })
-      Sentry.captureException(err)
-    })
-  })
+  }
 }
 
-const server = http.createServer(app.callback())
-destroyable(server)
-
-let shuttingDown = false,
-  errCode = 0
-
-server.on("close", async () => {
-  // already in process
-  if (shuttingDown) {
-    return
-  }
-  shuttingDown = true
-  console.log("Server Closed")
-  timers.cleanup()
-  await automations.shutdown()
-  await redis.shutdown()
-  events.shutdown()
-  await Thread.shutdown()
-  api.shutdown()
-  if (!env.isTest()) {
-    process.exit(errCode)
-  }
+start().catch(err => {
+  console.error(`Failed server startup - ${err.message}`)
 })
 
-export default server.listen(env.PORT || 0, async () => {
-  await startup(app, server)
-})
-
-const shutdown = () => {
-  server.close()
-  // @ts-ignore
-  server.destroy()
+export function getServer() {
+  return app
 }
-
-process.on("uncaughtException", err => {
-  // @ts-ignore
-  // don't worry about this error, comes from zlib isn't important
-  if (err && err["code"] === "ERR_INVALID_CHAR") {
-    return
-  }
-  errCode = -1
-  logging.logAlert("Uncaught exception.", err)
-  shutdown()
-})
-
-process.on("SIGTERM", () => {
-  shutdown()
-})
-
-process.on("SIGINT", () => {
-  shutdown()
-})

packages/server/src/automations/index.ts

@@ -2,6 +2,7 @@ import { processEvent } from "./utils"
 import { automationQueue } from "./bullboard"
 import { rebootTrigger } from "./triggers"
 import BullQueue from "bull"
+import { automationsEnabled } from "../features"
 
 export { automationQueue } from "./bullboard"
 export { shutdown } from "./bullboard"
@@ -12,6 +13,9 @@ export { BUILTIN_ACTION_DEFINITIONS, getActionDefinitions } from "./actions"
  * This module is built purely to kick off the worker farm and manage the inputs/outputs
  */
 export async function init() {
+  if (!automationsEnabled()) {
+    return
+  }
   // this promise will not complete
   const promise = automationQueue.process(async job => {
     await processEvent(job)

packages/server/src/automations/utils.ts

@@ -15,9 +15,13 @@ import {
   WebhookActionType,
 } from "@budibase/types"
 import sdk from "../sdk"
+import { automationsEnabled } from "../features"
 
 const WH_STEP_ID = definitions.WEBHOOK.stepId
-const Runner = new Thread(ThreadType.AUTOMATION)
+let Runner: Thread
+if (automationsEnabled()) {
+  Runner = new Thread(ThreadType.AUTOMATION)
+}
 
 function loggingArgs(
   job: AutomationJob,

packages/server/src/environment.ts

@@ -38,6 +38,8 @@ function parseIntSafe(number?: string) {
 }
 
 const environment = {
+  // features
+  APP_FEATURES: process.env.APP_FEATURES,
   // important - prefer app port to generic port
   PORT: process.env.APP_PORT || process.env.PORT,
   COUCH_DB_URL: process.env.COUCH_DB_URL,

packages/server/src/features.ts

@@ -0,0 +1,36 @@
+import env from "./environment"
+
+enum AppFeature {
+  API = "api",
+  AUTOMATIONS = "automations",
+}
+
+const featureList = processFeatureList()
+
+function processFeatureList() {
+  const fullList = Object.values(AppFeature) as string[]
+  let list
+  if (!env.APP_FEATURES) {
+    list = fullList
+  } else {
+    list = env.APP_FEATURES.split(",")
+  }
+  for (let feature of list) {
+    if (!fullList.includes(feature)) {
+      throw new Error(`Feature: ${feature} is not an allowed option`)
+    }
+  }
+  return list
+}
+
+export function isFeatureEnabled(feature: AppFeature) {
+  return featureList.includes(feature)
+}
+
+export function automationsEnabled() {
+  return featureList.includes(AppFeature.AUTOMATIONS)
+}
+
+export function apiEnabled() {
+  return featureList.includes(AppFeature.API)
+}

packages/server/src/koa.ts

@@ -0,0 +1,102 @@
+import env from "./environment"
+import { ExtendableContext } from "koa"
+import Koa from "koa"
+import koaBody from "koa-body"
+import http from "http"
+import * as api from "./api"
+import * as automations from "./automations"
+import { Thread } from "./threads"
+import * as redis from "./utilities/redis"
+import { events, logging, middleware, timers } from "@budibase/backend-core"
+const Sentry = require("@sentry/node")
+const destroyable = require("server-destroy")
+const { userAgent } = require("koa-useragent")
+
+export default function createKoaApp() {
+  const app = new Koa()
+
+  let mbNumber = parseInt(env.HTTP_MB_LIMIT || "10")
+  if (!mbNumber || isNaN(mbNumber)) {
+    mbNumber = 10
+  }
+  // set up top level koa middleware
+  app.use(
+    koaBody({
+      multipart: true,
+      formLimit: `${mbNumber}mb`,
+      jsonLimit: `${mbNumber}mb`,
+      textLimit: `${mbNumber}mb`,
+      // @ts-ignore
+      enableTypes: ["json", "form", "text"],
+      parsedMethods: ["POST", "PUT", "PATCH", "DELETE"],
+    })
+  )
+
+  app.use(middleware.correlation)
+  app.use(middleware.pino)
+  app.use(userAgent)
+
+  if (env.isProd()) {
+    app.on("error", (err: any, ctx: ExtendableContext) => {
+      Sentry.withScope(function (scope: any) {
+        scope.addEventProcessor(function (event: any) {
+          return Sentry.Handlers.parseRequest(event, ctx.request)
+        })
+        Sentry.captureException(err)
+      })
+    })
+  }
+
+  const server = http.createServer(app.callback())
+  destroyable(server)
+
+  let shuttingDown = false,
+    errCode = 0
+
+  server.on("close", async () => {
+    // already in process
+    if (shuttingDown) {
+      return
+    }
+    shuttingDown = true
+    console.log("Server Closed")
+    timers.cleanup()
+    await automations.shutdown()
+    await redis.shutdown()
+    events.shutdown()
+    await Thread.shutdown()
+    api.shutdown()
+    if (!env.isTest()) {
+      process.exit(errCode)
+    }
+  })
+
+  const listener = server.listen(env.PORT || 0)
+
+  const shutdown = () => {
+    server.close()
+    // @ts-ignore
+    server.destroy()
+  }
+
+  process.on("uncaughtException", err => {
+    // @ts-ignore
+    // don't worry about this error, comes from zlib isn't important
+    if (err && err["code"] === "ERR_INVALID_CHAR") {
+      return
+    }
+    errCode = -1
+    logging.logAlert("Uncaught exception.", err)
+    shutdown()
+  })
+
+  process.on("SIGTERM", () => {
+    shutdown()
+  })
+
+  process.on("SIGINT", () => {
+    shutdown()
+  })
+
+  return { app, server: listener }
+}

packages/server/src/startup.ts

@@ -17,6 +17,7 @@ import * as pro from "@budibase/pro"
 import * as api from "./api"
 import sdk from "./sdk"
 import { initialise as initialiseWebsockets } from "./websockets"
+import { automationsEnabled } from "./features"
 
 let STARTUP_RAN = false
 
@@ -97,7 +98,9 @@ export async function startup(app?: any, server?: any) {
   // configure events to use the pro audit log write
   // can't integrate directly into backend-core due to cyclic issues
   queuePromises.push(events.processors.init(pro.sdk.auditLogs.write))
+  if (automationsEnabled()) {
     queuePromises.push(automations.init())
+  }
   queuePromises.push(initPro())
   if (app) {
     // bring routes online as final step once everything ready

packages/server/src/tests/utilities/TestConfiguration.ts

@@ -87,7 +87,7 @@ class TestConfiguration {
     if (openServer) {
       // use a random port because it doesn't matter
       env.PORT = "0"
-      this.server = require("../../app").default
+      this.server = require("../../app").getServer()
       // we need the request for logging in, involves cookies, hard to fake
       this.request = supertest(this.server)
       this.started = true
@@ -178,7 +178,7 @@ class TestConfiguration {
     if (this.server) {
       this.server.close()
     } else {
-      require("../../app").default.close()
+      require("../../app").getServer().close()
     }
     if (this.allApps) {
       cleanup(this.allApps.map(app => app.appId))

packages/worker/src/environment.ts

@@ -31,6 +31,8 @@ function parseIntSafe(number: any) {
 }
 
 const environment = {
+  // features
+  WORKER_FEATURES: process.env.WORKER_FEATURES,
   // auth
   MINIO_ACCESS_KEY: process.env.MINIO_ACCESS_KEY,
   MINIO_SECRET_KEY: process.env.MINIO_SECRET_KEY,

packages/worker/src/features.ts

@@ -0,0 +1,26 @@
+import env from "./environment"
+
+enum WorkerFeature {}
+
+const featureList: WorkerFeature[] = processFeatureList()
+
+function processFeatureList() {
+  const fullList = Object.values(WorkerFeature) as string[]
+  let list
+  if (!env.WORKER_FEATURES) {
+    list = fullList
+  } else {
+    list = env.WORKER_FEATURES.split(",")
+  }
+  for (let feature of list) {
+    if (!fullList.includes(feature)) {
+      throw new Error(`Feature: ${feature} is not an allowed option`)
+    }
+  }
+  // casting ok - confirmed definitely is a list of worker features
+  return list as unknown as WorkerFeature[]
+}
+
+export function isFeatureEnabled(feature: WorkerFeature) {
+  return featureList.includes(feature)
+}