feat(migration): adjust BackendProcess, main.dev.js & App.ts so…

… we can coordinate migrations! (#571)

* refactor(backend.js): emit messages to renderer process during backend launch

We refactor the `BackendProcess` class to have specific methods that the main process can use to orchestrate launching the backend app
Because we can only emit events to the renderer process in the main process (so no way to emit them in `BackendProcess`, unless we pass the `mainWindow` down to the `BackendProcess` class) this exposes a bunch of launching functionality to the main process (it was previously all hidden in the `backendProcess.maybeStartup()` function)

In future refactors, am definitely open to pushing `mainWindow` down to `BackendProcess` and dealing with all aspects down there. However, as a first iteration I think this is fine.

The logic for this the start up goes like this:
- if a backend process is already running, error. Catch the error & send a message to the renderer that a qri backend is already running
- check if we have a compatible backend version. If it's too low, send a message to the renderer that the version is incompatible
- check if we need a migration - if we do, send a message to the renderer that we are migrating
- launch the backend

* refactor(ui reducer): add `bootupComponent` as field on `state.ui`

- add `BootupComponentType`
- `state.ui.bootupComponet` defaults to 'loading'
- add `UI_SET_BOOTUP_COMPONENT` action type
- add `setBootstrapComponent` action
- add `selectBootstrapComponent` selector

* refactor(`main`): need to wait for app to be loaded before coordinating

Both the renderer process and main process need to be on before we can successfully coordinate behavior.

`App` component now emits an `app-fully-loaded` event.

Moved the backend launching process into the ipcMain `app-fully-loaded` event handler. This also means that whenever the app re-loads, we check for a backend connection, and if we don't find one we launch again. Which I think is a nice pick up!

Downside is we get slightly longer loading time in dev mode (since it takes a bit to compile the app), but no discernible changes in prod mode!

* refactor(backend): saner `checkNeedsMigration` function

now that the backend flags/expectations have changed, we can run any comand to see if it exits with code `2` (which indicates that a migration is needed)

* refactor(backend.js): use correct flags in `qri connect` & use `qri config` as migration check

app/actions/ui.ts

@@ -9,10 +9,11 @@ import {
   UI_SET_DATASET_DIR_PATH,
   UI_SET_EXPORT_PATH,
   UI_SET_DETAILS_BAR,
-  UI_SET_IMPORT_FILE_DETAILS
+  UI_SET_IMPORT_FILE_DETAILS,
+  UI_SET_BOOTUP_COMPONENT
 } from '../reducers/ui'
 
-import { ToastType } from '../models/store'
+import { ToastType, BootupComponentType } from '../models/store'
 import { Modal, ModalType } from '../models/modals'
 import { Details } from '../models/details'
 
@@ -100,3 +101,10 @@ export const setImportFileDetails = (fileName: string, fileSize: number) => {
     fileSize
   }
 }
+
+export const setBootupComponent = (component: BootupComponentType) => {
+  return {
+    type: UI_SET_BOOTUP_COMPONENT,
+    component
+  }
+}

app/backend.js

@@ -1,21 +1,38 @@
 const log = require('electron-log')
 const childProcess = require('child_process')
 const fs = require('fs')
+const yaml = require('js-yaml')
 const path = require('path')
 const os = require('os')
+const http = require('http')
 const { dialog } = require('electron')
 
+const lowestCompatibleBackend = [0, 9, 9]
 
 // BackendProcess runs the qri backend binary in connected'ed mode, to handle api requests.
 class BackendProcess {
   constructor () {
     this.qriBinPath = null
     this.process = null
     this.debugLogPath = null
+    this.backendVer = null
 
     // Default to writing to stdout & stderr
     this.out = process.stdout
-    this.err = process.stderr
+    this.in = process.in
+    this.err = process.stderr;
+
+    [
+      'setQriBinPath',
+      'setBackendVer',
+      'standardRepoPath',
+      'checkNoActiveBackendProcess',
+      'checkBackendCompatibility',
+      'checkNeedsMigration',
+      'launchProcess'
+    ].forEach((m) => { this[m] = this[m].bind(this) })
+
+
     try {
       // Create a log whose filename contains the current day.
       const nowTime = new Date();
@@ -41,9 +58,12 @@ class BackendProcess {
         detail: err
       })
     }
+    this.setQriBinPath()
+    this.setBackendVer()
   }
 
-  maybeStartup () {
+  // running this function will ensure that a qriBinPath exists
+  setQriBinPath () {
     // In development node, use installed qri binary
     if (process.env.NODE_ENV === 'development') {
       let processResult = childProcess.execSync('which qri');
@@ -59,12 +79,17 @@ class BackendProcess {
     }
 
     if (!this.qriBinPath) {
-      log.warn('no qri bin path found, backend launch')
-      return
+      log.warn('no qri bin path found, backend launch failed')
+      throw new Error("no qri bin path found, backend launch failed")
     }
-    // Run the binary if it is found
     log.info(`found qri binary at path: ${this.qriBinPath}`)
-    this.launchProcess()
+  }
+
+  setBackendVer () {
+    let processResult = childProcess.execSync(`"${this.qriBinPath}" version`)
+    this.backendVer = processResult.toString().trim()
+    log.info("qri backend version", this.backendVer)
+
   }
 
   close () {
@@ -74,16 +99,66 @@ class BackendProcess {
     }
   }
 
+  standardRepoPath() {
+    var qriRepoPath = process.env.QRI_PATH
+    if (qriRepoPath === "") {
+      home = os.homedir()
+      qriRepoPath = path.join(home, ".qri")
+    }
+
+    log.info(`QRI_PATH is ${qriRepoPath}`)
+    return qriRepoPath
+  }
+
+  async checkNoActiveBackendProcess() {
+    const healthCheck = async () => {
+      return new Promise((res, rej) => {
+        http.get('http://localhost:2503/health', (data) => {
+          res(true)
+        }).on('error', (e) => {
+          res(false)
+        })
+      })
+    }
+
+    var isQriRunning = await healthCheck()
+    if (isQriRunning) {
+      throw new Error("backend-already-running")
+    }
+    return
+  }
+
+  async checkBackendCompatibility () {
+    log.info(`checking to see if given backend version ${this.backendVer} is compatible with expected version ${lowestCompatibleBackend.join(".")}`)
+    let compatible = false
+    try {
+      let ver = this.backendVer
+      if (this.backendVer.indexOf("-dev") !== -1) {
+        ver = ver.slice(0, this.backendVer.indexOf("-dev"))
+      }
+      ver = ver.split(".").map((i) => parseInt(i))
+      compatible = lowestCompatibleBackend.every((val, i) => {
+        if (val <= ver[i]) {
+          return true
+        }
+        return false
+      })
+    } catch (e) {
+      throw e
+    }
+    if (!compatible) {
+      throw new Error("incompatible-backend")
+    }
+  }
+
   launchProcess () {
     try {
-      let processResult = childProcess.execSync(`"${this.qriBinPath}" version`)
-      let qriBinVersion = processResult.toString().trim();
-      this.process = childProcess.spawn(this.qriBinPath, ['connect', '--setup', '--log-all'], { stdio: ['ignore', this.out, this.err] })
+      this.process = childProcess.spawn(this.qriBinPath, ['connect', '--migrate', '--log-all', '--setup', '--no-prompt'], { stdio: ['ignore', this.out, this.err] })
       this.process.on('error', (err) => { this.handleEvent('error', err) })
       this.process.on('exit', (err) => { this.handleEvent('exit', err) })
       this.process.on('close', (err) => { this.handleEvent('close', err) })
       this.process.on('disconnect', (err) => { this.handleEvent('disconnect', err) })
-      log.info(`starting up qri backend version ${qriBinVersion}`)
+      log.info(`starting up qri backend version ${this.backendVer}`)
     } catch (err) {
       log.error(`starting background process: ${err}`)
     }
@@ -92,11 +167,26 @@ class BackendProcess {
   handleEvent (kind, err) {
     if (err) {
       log.error(`event ${kind} from backend: ${err}`)
+      throw err
     } else {
       log.warn(`event ${kind} from backend`)
     }
   }
 
+  checkNeedsMigration() {
+    log.info("checking for backend migrations")
+    try {
+      childProcess.execSync(`"${this.qriBinPath}" config get`)
+    } catch (err) {
+      // status code 2 means we need to run a migration
+      if (err.status == 2) {
+        return true
+      }
+      log.error(`error checking for migration: ${err}`)
+    }
+    return false
+  }
+
   findQriBin (pathList) {
     for (let i = 0; i < pathList.length; i++) {
       let binPath = path.join(pathList[i], '/backend/qri')

app/components/App.tsx

@@ -13,19 +13,19 @@ import { DEFAULT_POLL_INTERVAL } from '../constants'
 import { history } from '../store/configureStore.development'
 import { ApiAction } from '../store/api'
 import { Modal, ModalType } from '../models/modals'
-import { Selections, ApiConnection } from '../models/store'
+import { Selections, ApiConnection, BootupComponentType } from '../models/store'
 import { Session } from '../models/session'
 
 // import util funcs
 import { connectComponentToProps } from '../utils/connectComponentToProps'
 
 // import actions
-import { setModal } from '../actions/ui'
+import { setModal, setBootupComponent } from '../actions/ui'
 import { pingApi } from '../actions/api'
 import { bootstrap } from '../actions/session'
 
 // import selections
-import { selectSelections, selectModal, selectApiConnection, selectSession } from '../selections'
+import { selectSelections, selectModal, selectApiConnection, selectSession, selectBootupComponent } from '../selections'
 
 // import components
 import Toast from './Toast'
@@ -34,10 +34,14 @@ import AppError from './AppError'
 import AppLoading from './AppLoading'
 import Modals from './modals/Modals'
 import Routes from '../routes'
+import MigratingBackend from './MigratingBackend'
+import MigrationFailed from './MigrationFailed'
+import IncompatibleBackend from './IncompatibleBackend'
 
 // declare interface for props
 export interface AppProps {
   loading: boolean
+  bootupComponent: BootupComponentType
   session: Session
   selections: Selections
   apiConnection?: ApiConnection
@@ -46,6 +50,7 @@ export interface AppProps {
 
   push: (path: string) => void
   setModal: (modal: Modal) => Action
+  setBootupComponent: (component: BootupComponentType) => Action
 
   bootstrap: () => Promise<ApiAction>
   pingApi: () => Promise<ApiAction>
@@ -73,6 +78,14 @@ class AppComponent extends React.Component<AppProps, AppState> {
     this.handleReload = this.handleReload.bind(this)
     this.handleSetDebugLogPath = this.handleSetDebugLogPath.bind(this)
     this.handleExportDebugLog = this.handleExportDebugLog.bind(this)
+    this.handleIncompatibleBackend = this.handleIncompatibleBackend.bind(this)
+    this.handleMigratingBackend = this.handleMigratingBackend.bind(this)
+    this.handleMigrationFailure = this.handleMigrationFailure.bind(this)
+    this.handleStartingBackend = this.handleStartingBackend.bind(this)
+  }
+
+  private handleStartingBackend () {
+    console.log("started backend message received")
   }
 
   private handleCreateDataset () {
@@ -112,6 +125,18 @@ class AppComponent extends React.Component<AppProps, AppState> {
     fs.copyFileSync(this.state.debugLogPath, exportFilename)
   }
 
+  private handleIncompatibleBackend (_: Electron.IpcRendererEvent, ver: string) {
+    this.props.setBootupComponent(ver)
+  }
+
+  private handleMigratingBackend () {
+    this.props.setBootupComponent('migrating')
+  }
+
+  private handleMigrationFailure () {
+    this.props.setBootupComponent('migrationFailure')
+  }
+
   componentDidMount () {
     // handle ipc events from electron menus
     ipcRenderer.on('create-dataset', this.handleCreateDataset)
@@ -120,6 +145,12 @@ class AppComponent extends React.Component<AppProps, AppState> {
     ipcRenderer.on('set-debug-log-path', this.handleSetDebugLogPath)
     ipcRenderer.on('export-debug-log', this.handleExportDebugLog)
     ipcRenderer.on('reload', this.handleReload)
+    ipcRenderer.on('incompatible-backend', this.handleIncompatibleBackend)
+    ipcRenderer.on('migrating-backend', this.handleMigratingBackend)
+    ipcRenderer.on('migration-failed', this.handleMigrationFailure)
+    ipcRenderer.on("starting-backend", this.handleStartingBackend)
+
+    ipcRenderer.send("app-fully-loaded")
 
     setInterval(() => {
       if (this.props.apiConnection !== 1) {
@@ -138,6 +169,10 @@ class AppComponent extends React.Component<AppProps, AppState> {
     ipcRenderer.removeListener('history-push', this.handlePush)
     ipcRenderer.removeListener('set-debug-log-path', this.handleSetDebugLogPath)
     ipcRenderer.removeListener('reload', this.handleReload)
+    ipcRenderer.removeListener('incompatible-backend', this.handleIncompatibleBackend)
+    ipcRenderer.removeListener('migrating-backend', this.handleMigratingBackend)
+    ipcRenderer.removeListener('migration-failed', this.handleMigrationFailure)
+    ipcRenderer.removeListener("starting-backend", this.handleStartingBackend)
   }
 
   componentDidUpdate (prevProps: AppProps) {
@@ -151,20 +186,52 @@ class AppComponent extends React.Component<AppProps, AppState> {
   }
 
   render () {
-    const { apiConnection, modal, loading } = this.props
+    const { apiConnection, modal, loading, bootupComponent } = this.props
 
     if (loading) {
       return (
-        <CSSTransition
-          in={loading}
-          classNames="fade"
-          component="div"
-          timeout={1000}
-          mountOnEnter
-          unmountOnExit
-        >
-          <AppLoading />
-        </CSSTransition>
+        <>
+          <CSSTransition
+            in={bootupComponent === 'loading'}
+            classNames="fade"
+            component="div"
+            timeout={1000}
+            mountOnEnter
+            unmountOnExit
+          >
+            <AppLoading />
+          </CSSTransition>
+          <CSSTransition
+            in={bootupComponent === 'migrating'}
+            classNames="fade"
+            component="div"
+            timeout={1000}
+            mountOnEnter
+            unmountOnExit
+          >
+            <MigratingBackend />
+          </CSSTransition>
+          <CSSTransition
+            in={bootupComponent === 'migrationFailure'}
+            classNames="fade"
+            component="div"
+            timeout={1000}
+            mountOnEnter
+            unmountOnExit
+          >
+            <MigrationFailed />
+          </CSSTransition>
+          <CSSTransition
+            in={bootupComponent !== 'loading' && bootupComponent !== 'migrating' && bootupComponent !== 'migrationFailure'}
+            classNames="fade"
+            component="div"
+            timeout={1000}
+            mountOnEnter
+            unmountOnExit
+          >
+            <IncompatibleBackend incompatibleVersion={bootupComponent} />
+          </CSSTransition>
+        </>
       )
     }
 
@@ -228,6 +295,7 @@ export default connectComponentToProps(
       selections: selectSelections(state),
       apiConnection,
       modal: selectModal(state),
+      bootupComponent: selectBootupComponent(state),
       ...ownProps
     }
   },
@@ -236,6 +304,7 @@ export default connectComponentToProps(
     push,
     setModal,
     bootstrap,
+    setBootupComponent,
     pingApi
   }
 )