Google AppEngine - Managed VM

From: https://www.gitbook.com/content/book/peihsinsu/node-js-500-samples/

Managed VM是Google App Engine所推出的PaaS - AppEngine服務的延伸，透過Linux Container的技術與AppEngine frontend的搭配，讓整個AppEngine的功能無限延伸。

本服務仍在Beta階段，但是整體的服務概念已經大致完成，筆者也正在著手測試穩定性與可用性當中，有興趣的朋友可以一起參加Google的測試...

準備Managed VM環境

安裝boot2docker

您可以到boot2docker的官方下載點，下載boot2docker以供安裝。安裝後，即可執行boot2docker的指令，並解僵boot2docker環境啟動...

boot2docker init$ boot2docker up$ $(boot2docker shellinit)

安裝google cloud sdk

Mac環境下，透過curl即可下載安裝google cloud sdk...，其他環境可以參考Google官方說明

curl https://sdk.cloud.google.com | bash

安裝完cloud sdk之後，需要下載開發人員預覽版本的指令庫...

gcloud components update app

準備開發 - 以express為範例

安裝相關套件

$ sudo npm install express-generator -g

建置express專案

$ express -e myapp

$ cd myapp

增加app.yaml設定檔

app.yaml是AppEngine環境的設定檔，目的是提供frontend instance (appengine)與backend instance (managed vm)之間的呼叫介面，以下面設定為例，即是讓所有的路由均由app.js提供服務...

version: 2

runtime: custom

vm: true

api_version: 1

manual_scaling:

instances: 1

handlers:

- url: /.*

script: app.js

建立"Dockerfile"檔案

Dockerfile是作為未來部署Managed VM環境的依據，您可以依照希望執行的Backend狀態來庭整這個設定檔。在此，我們只有單純把docker賦予node.js的環境，因此僅僅使用Google所提供的base image即可...

FROM google/nodejs-runtime

如果對Docker有興趣，您可以到docker hub檢視Google node.js runtime的docker build file (參考)，可以了解實際Managed VM執行的環境與狀態...

編輯package.json，引入appengine模組

在package.json中加入appengine的dependency，該套件提供了與AppEngine整合的一些操作方法，讓應用程式得以與Google其他服務互動。

{ "name": "test", "version": "0.0.0", "private": true, "scripts": { "start": "node ./bin/www" }, "dependencies": { "body-parser": "~1.12.0", "cookie-parser": "~1.3.4", "debug": "~2.1.1", "ejs": "~2.3.1", "express": "~4.12.0", "morgan": "~1.5.1", "serve-favicon": "~2.2.0", "appengine" : "git://github.com/GoogleCloudPlatform/appengine-nodejs.git" }}

修改express設定檔

加入appengine的import

var appengine = require('appengine');

並且於app.use部分加入appengine middleware模組

app.use(appengine.middleware.base);

建立系統預設路由 - /_ah/*

加入Managed VM的health check routes


app.get('/_ah/health', function(req, res) {



  res.set('Content-Type', 'text/plain');



  res.send(200, 'ok');


});


app.get('/_ah/start', function(req, res) {

  res.set('Content-Type', 'text/plain');

  res.send(200, 'ok');

});


app.get('/_ah/stop', function(req, res) {

  res.set('Content-Type', 'text/plain');

  res.send(200, 'ok');

  process.exit();

});

修改啟動port至8080

開啟bin/www檔案，將預設port修改為8080

var port = normalizePort(process.env.PORT || '8080');

預先測試

在未佈署到docker環境錢，該專案可以在npm install安裝完相依套件後，使用npm start測試是否可以正常執行。

npm install && npm start

可以如此測試是因為Docker build file中有指定docker instance開立起來後，是以npm start來喚起所要執行的專案... 因此我們可以使用這個方式來測試該專案到container中是否可以正常執行...

本地端執行Managed VM

本地端執行Managed VM時，需要搭配boot2docker已經開啟的狀態下，切換到專案目錄中，執行下面指令：

$ gcloud preview app run .

Module [default] found in file [/private/tmp/test/app.yaml]

INFO: Looking for the Dockerfile in /private/tmp/test

INFO: Using Dockerfile found in /private/tmp/test

INFO 2015-03-04 15:53:04,198 devappserver2.py:726] Skipping SDK update check.

INFO 2015-03-04 15:53:04,293 api_server.py:172] Starting API server at: http://localhost:62335

INFO 2015-03-04 15:53:04,365 containers.py:259] Building docker image managedvm-project.default.2 from /private/tmp/test/Dockerfile:

INFO 2015-03-04 15:53:04,365 containers.py:261] -------------------- DOCKER BUILD --------------------

INFO 2015-03-04 15:53:04,366 dispatcher.py:186] Starting module "default" running at: http://localhost:8080

INFO 2015-03-04 15:53:04,370 admin_server.py:118] Starting admin server at: http://localhost:8000

INFO 2015-03-04 15:53:04,873 containers.py:280] # Executing 3 build triggers

INFO 2015-03-04 15:53:04,874 containers.py:280] Trigger 0, ADD package.json /app/

INFO 2015-03-04 15:53:04,874 containers.py:280] Step 0 : ADD package.json /app/

INFO 2015-03-04 15:53:04,879 containers.py:280] ---> Using cache

INFO 2015-03-04 15:53:04,879 containers.py:280] Trigger 1, RUN npm install

INFO 2015-03-04 15:53:04,879 containers.py:280] Step 0 : RUN npm install

INFO 2015-03-04 15:53:04,917 containers.py:280] ---> Using cache

INFO 2015-03-04 15:53:04,918 containers.py:280] Trigger 2, ADD . /app

INFO 2015-03-04 15:53:04,918 containers.py:280] Step 0 : ADD . /app

INFO 2015-03-04 15:53:04,937 containers.py:280] ---> Using cache

INFO 2015-03-04 15:53:04,937 containers.py:280] ---> cd272a90bc21

INFO 2015-03-04 15:53:04,938 containers.py:280] Successfully built cd272a90bc21

INFO 2015-03-04 15:53:04,948 containers.py:292] --------------------------------------------------------

INFO 2015-03-04 15:53:04,948 containers.py:304] Image managedvm-project.default.2 built, id = cd272a90bc21

INFO 2015-03-04 15:53:04,948 containers.py:534] Creating container...

INFO 2015-03-04 15:53:05,104 containers.py:560] Container ef5775aa5d26ade2d524dd44d0cf6a18fa6c5c7aa100ccb3f925e3af30e5b72a created.

INFO 2015-03-04 15:53:06,407 module.py:1692] New instance for module "default" serving on:

http://localhost:8080

INFO 2015-03-04 15:53:06,435 module.py:737] default: "GET /_ah/start HTTP/1.1" 200 2

INFO 2015-03-04 15:53:06,435 health_check_service.py:101] Health checks starting for instance 0.

佈署Managed VM

如開發上一切都順利，接下來可以執行部屬的動作，透過docker preview app deploy來作佈署...


$ gcloud preview app deploy .



11:53 PM Host: appengine.google.com
11:53 PM Host: appengine.google.com



{bucket: vm-containers.managedvm-project.appspot.com, path: /containers}
{bucket: vm-containers.managedvm-project.appspot.com, path: /containers}






Updating module [default] from file [/private/tmp/test/app.yaml]
Updating module [default] from file [/private/tmp/test/app.yaml]



Pushing image to Google Cloud Storage...managedvm-project
Pushing image to Google Cloud Storage...managedvm-project



Sending image list
Sending image list



Pushing repository gcr.io/_m_managedvm-project/managedvm-project.default.2 (1 tags)
Pushing repository gcr.io/_m_managedvm-project/managedvm-project.default.2 (1 tags)



Image 541923dd11eb already pushed, skipping
Image 541923dd11eb already pushed, skipping



Image 11971b6377ef already pushed, skipping
Image 11971b6377ef already pushed, skipping



...(skip)
...(skip)



Image b62c4c483651 already pushed, skipping
Image b62c4c483651 already pushed, skipping



Pushing
Pushing



Buffering to disk:  2.56 kB
Buffering to disk:  2.56 kB



Image successfully pushed===================================>]  2.56 kB/2.56 kB 0s
Image successfully pushed===================================>]  2.56 kB/2.56 kB 0s



Pushing
Pushing



Buffering to disk: 9.834 MB
Buffering to disk: 9.834 MB



Image successfully pushed===================================>] 9.834 MB/9.834 MB 0ss
Image successfully pushed===================================>] 9.834 MB/9.834 MB 0ss



Pushing
Pushing



Buffering to disk: 2.629 MB
Buffering to disk: 2.629 MB



Image successfully pushed===================================>] 2.629 MB/2.629 MB 0ss1s
Image successfully pushed===================================>] 2.629 MB/2.629 MB 0ss1s



Pushing tag for rev [c7685fe2aad2] on {https://gcr.io/v1/repositories/_m_managedvm-project/managedvm-project.default.2/tags/latest}
Pushing tag for rev [c7685fe2aad2] on {https://gcr.io/v1/repositories/_m_managedvm-project/managedvm-project.default.2/tags/latest}



11:54 PM Host: appengine.google.com
11:54 PM Host: appengine.google.com



11:54 PM Application: managedvm-project (was: None); version: 2
11:54 PM Application: managedvm-project (was: None); version: 2



11:54 PM
11:54 PM



Starting update of app: managedvm-project, version: 2
Starting update of app: managedvm-project, version: 2



11:54 PM Getting current resource limits.managedvm-project
11:54 PM Getting current resource limits.managedvm-project



11:54 PM Scanning files on local disk.
11:54 PM Scanning files on local disk.



^@11:54 PM WARNING: Performance settings included in this update are being ignored because your application is not using the Modules feature. See the Modules documentation for more information. Python: https://developers.google.com/appengine/docs/python/modules/ Java: https://developers.google.com/appengine/docs/java/modules/ Go: https://developers.google.com/appengine/docs/go/modules/ PHP: https://developers.google.com/appengine/docs/php/modules/.
^@11:54 PM WARNING: Performance settings included in this update are being ignored because your application is not using the Modules feature. See the Modules documentation for more information. Python: https://developers.google.com/appengine/docs/python/modules/ Java: https://developers.google.com/appengine/docs/java/modules/ Go: https://developers.google.com/appengine/docs/go/modules/ PHP: https://developers.google.com/appengine/docs/php/modules/.



11:54 PM Cloning 291 application files.
11:54 PM Cloning 291 application files.



11:54 PM Uploading 51 files and blobs.
11:54 PM Uploading 51 files and blobs.



11:55 PM Uploaded 51 files and blobs.
11:55 PM Uploaded 51 files and blobs.



11:55 PM Starting deployment.
11:55 PM Starting deployment.



11:55 PM Checking if deployment succeeded.
11:55 PM Checking if deployment succeeded.



11:55 PM Deployment successful.
11:55 PM Deployment successful.



11:55 PM Checking if updated app version is serving.
11:55 PM Checking if updated app version is serving.



11:55 PM Will check again in 5 seconds.
11:55 PM Will check again in 5 seconds.



...(skip)
...(skip)



11:57 PM Checking if updated app version is serving.
11:57 PM Checking if updated app version is serving.



11:57 PM Enough VMs ready (1/1 ready).
11:57 PM Enough VMs ready (1/1 ready).



11:57 PM Completed update of app: managedvm-project, version: 2
11:57 PM Completed update of app: managedvm-project, version: 2


以上文章，已收錄到Gitbook：http://peihsinsu.gitbooks.io/node-js-500-samples/

Node.js in Example

2015年3月4日星期三