在 Amazon Lightsail 上部署容器 Web 應用程式
入門指南
單元 4:部署新的容器版本
在本單元中,您將學習更新已經部署的容器
簡介
在應用程式的生命中會歷經多次更新。在本單元中,您將學習遇到新應用程式版本發佈時,如何更新部署,以及如何回復部署。
您將學到的內容
- 更新應用程式碼,及建置新的本機容器映像
- 推送更新後的容器映像至 Amazon Lightsail
- 部署新版本的應用程式
- 萬一出現錯誤時回復部署
完成時間
10 分鐘
單元先決條件
- 有管理員等級存取權限的 AWS 帳戶**
- 建議的瀏覽器:最新版的 Chrome 或 Firefox
[**]過去 24 小時內建立的帳戶可能尚未有權存取本教學課程所需的服務。
實作
更新您的應用程式碼,及建置新的容器映像
現在假設應用程式首頁上的城市名稱不正確,需要修改。
開啟檔案 code/templates/index.html。搜尋 "Las Vegas",取代為 "Paris"。
接著,依照單元 2 所解說,建置並測試容器。開啟一個終端機,然後鍵入以下命令:
# build the container
docker build -t demo-flask-signup .
# run the container for local testing
docker run -p 8080:80 \
--rm \
-v ~/.aws:/root/.aws \
demo-flask-signup:latest
現在容器已開始執行,請開啟瀏覽器,指向其位址 http://localhost:8080。即應顯示應用程式首頁,並為新城市名稱。

推送更新後的容器映像至 Amazon Lightsail
現在容器已建置完成,下一個步驟是將這個新容器映像推送至 Amazon Lightsail。
開啟一個終端機,然後鍵入以下命令:
aws lightsail push-container-image \
--region eu-west-3 \
--service-name signup-application \
--label latest \
--image demo-flask-signup:latest
# the command outputs the following lines
df0f7d33bb59: Pushed
951ffe99d911: Pushed
cee40450fe90: Pushed
1327150a5178: Pushed
4bc5d67b6427: Layer already exists
ce8ffb5c560e: Layer already exists
4226d5d0360f: Layer already exists
9d1af766c818: Layer already exists
d97733c0a3b6: Layer already exists
c553c6ba5f13: Layer already exists
48b4a40de359: Layer already exists
ace9ed9bcfaf: Layer already exists
764055ebc9a7: Layer already exists
Digest: sha256:42d2e19ee7340bc7f028593318e9b7406e9e70fb4785618d3f6c78443e097a87
Image "demo-flask-signup:latest" registered.
Refer to this image as ":signup-application.latest.2" in deployments.
輸出的最後一行顯示出容器的內部名稱。請記下來,因為將容器部署至容器服務時會需要用到這個名稱。如果您在稍後想要存取容器名稱,可鍵入以下命令:
aws lightsail get-container-images \
--region eu-west-3 \
--service-name signup-application
# the command outputs the following lines
{
"containerImages": [
{
"image": ":signup-application.latest.2",
"digest": "sha256:42d2e19ee7340bc7f028593318e9b7406e9e70fb4785618d3f6c78443e097a87",
"createdAt": "2021-07-17T18:34:00+02:00"
},
{
"image": ":signup-application.latest.1",
"digest": "sha256:128f84907d30a1fb47c1888720485fa8050cc99bc1034e0cfd1f46d3b6e57e19",
"createdAt": "2021-07-17T15:11:49+02:00"
}
]
}
請注意 "state": "DEPLOYING" 的狀態。經過一會兒,狀態會變成 ACTIVE。完成部署需要幾分鐘。您可使用以下命令檢查部署的狀態:
# while deploying
aws lightsail get-container-services \
--region eu-west-3 \
--query "containerServices[].nextDeployment.state"
# once deployed
aws lightsail get-container-services \
--region eu-west-3 \
--query "containerServices[].currentDeployment.state"
測試您的部署
若要測試部署,請先擷取為您建立的 URL Lightsail。開啟一個終端機,然後鍵入以下命令:
aws lightsail get-container-services \
--region eu-west-3 \
--query "containerServices[].url"
# the command outputs something like the below
[
"https://signup-application.me04fvc6dbk4e.eu-west-3.cs.amazonlightsail.com/"
]
我們現在有容器映像的兩個版本 - :signup-application.latest.1 和 :signup-application.latest.2。
部署新版本的應用程式
現在容器映像已存放在 Amazon Lightsail,我們可將該映像部署至容器服務,作法是使用類似上一單元所說明的命令:部署容器。
編輯 lc.json 檔案,將所使用的映像名稱 - :signup-application.latest.1 - 取代為新版本 :signup-application.latest.2。
新的 lc.json 檔案看起來應像這樣:
{
"serviceName": "signup-application",
"containers": {
"signup-app-container": {
"image": ":signup-application.latest.2",
"ports": {
"80": "HTTP"
}
}
},
"publicEndpoint": {
"containerName": "signup-app-container",
"containerPort": 80
}
}
接著,鍵入以下命令以部署容器:
aws lightsail create-container-service-deployment \
--region eu-west-3 \
--cli-input-json file://lc.json
# the command outputs the following
測試您的部署
若要測試部署,請切換至您的瀏覽器視窗,重新整理前一單元所提供容器服務 URL 的頁面。
若要擷取 URL,可在終端機中鍵入此命令:
aws lightsail get-container-services \
--region eu-west-3 \
--query "containerServices[].url"
# the command outputs something like the below
[
"https://signup-application.me04fvc6dbk4e.eu-west-3.cs.amazonlightsail.com/"
]
回復部署
最後的部署並未覆寫應用程式的第一版,只是建立新版本。
若要確認可用版本,請開啟一個終端機,然後鍵入以下命令:
aws lightsail get-container-service-deployments \
--region eu-west-3 \
--service-name signup-application
# the command outputs a JSON similar to this one
{
"deployments": [
{
"version": 2,
"state": "ACTIVE",
"containers": {
"signup-app-container": {
"image": ":signup-application.latest.2",
"command": [],
"environment": {},
"ports": {
"80": "HTTP"
}
}
},
"publicEndpoint": {
"containerName": "signup-app-container",
"containerPort": 80,
"healthCheck": {
"healthyThreshold": 2,
"unhealthyThreshold": 2,
"timeoutSeconds": 2,
"intervalSeconds": 5,
"path": "/",
"successCodes": "200-499"
}
},
"createdAt": "2021-07-17T18:40:58+02:00"
},
{
"version": 1,
"state": "INACTIVE",
"containers": {
"signup-app-container": {
"image": ":signup-application.latest.1",
"command": [],
"environment": {},
"ports": {
"80": "HTTP"
}
}
},
"publicEndpoint": {
"containerName": "signup-app-container",
"containerPort": 80,
"healthCheck": {
"healthyThreshold": 2,
"unhealthyThreshold": 2,
"timeoutSeconds": 2,
"intervalSeconds": 5,
"path": "/",
"successCodes": "200-499"
}
},
"createdAt": "2021-07-17T15:31:01+02:00"
}
]
}
閱讀上個命令的輸出,可觀察出建立有兩個部署。版本 1 為 INACTIVE 狀態,版本 2 則為 ACTIVE。
以下命令可為您的部署提供較為精簡的概觀:
aws lightsail get-container-service-deployments \
--region eu-west-3 \
--service-name signup-application \
--query 'deployments[].{version: version, state: state, image: containers."signup-app-container".image}'
# the command outputs something similar to
[
{
"version": 2,
"state": "ACTIVE",
"image": ":signup-application.latest.2"
},
{
"version": 1,
"state": "INACTIVE",
"image": ":signup-application.latest.1"
}
]
現在請想像您剛部署的應用程式最新版本行為表現不正確。可能是在測試的時候錯誤並未浮現。
若要存取容器的記錄,請開啟終端機,鍵入以下命令:
aws lightsail get-container-log \
--region eu-west-3 \
--service-name signup-application \
--container-name signup-app-container \
--output text
# the command outputs log lines similar to this
LOGEVENTS 2021-07-17T18:14:51+02:00 [pid: 26|app: 0|req: 5821/5821] 172.26.7.236 () {34 vars in 401 bytes} [Sat Jul 17 16:14:51 2021] GET / => generated 4579 bytes in 0 msecs (HTTP/1.1 200) 2 headers in 81 bytes (1 switches on core 0)
LOGEVENTS 2021-07-17T18:14:51+02:00 [pid: 23|app: 0|req: 5824/5824] 172.26.7.236 () {34 vars in 402 bytes} [Sat Jul 17 16:14:51 2021] GET / => generated 4579 bytes in 0 msecs (HTTP/1.1 200) 2 headers in 81 bytes (1 switches on core 0)
LOGEVENTS 2021-07-17T18:14:51+02:00 172.26.7.236 - - [17/Jul/2021:16:14:51 +0000] "GET / HTTP/1.1" 200 4579 "-" "ELB-HealthChecker/2.0" "-"
為了快速回復部署,並重新部署上一版本的應用程式,請變更 lc.json 檔案,使其使用容器映像的第一版,並且重新部署這個映像。
將 lc.json 檔案修改成為如下所示:
# update the lc.json file
{
"serviceName": "signup-application",
"containers": {
"signup-app-container": {
"image": ":signup-application.latest.1",
"ports": {
"80": "HTTP"
}
}
},
"publicEndpoint": {
"containerName": "signup-app-container",
"containerPort": 80
}
}
接著在終端機中執行以下命令:
aws lightsail create-container-service-deployment \
--region eu-west-3 \
--cli-input-json file://lc.json
# the command outputs the following
{
"containerService": {
"containerServiceName": "signup-application",
"arn": "arn:aws:lightsail:eu-west-3:486652066693:ContainerService/528a0bcf-fd14-42d4-a09a-943a241adc51",
"createdAt": "2021-07-17T13:38:40+02:00",
"location": {
"availabilityZone": "all",
"regionName": "eu-west-3"
},
"resourceType": "ContainerService",
"tags": [],
"power": "nano",
"powerId": "nano-1",
"state": "DEPLOYING",
"scale": 2,
"currentDeployment": {
"version": 2,
"state": "ACTIVE",
"containers": {
"signup-app-container": {
"image": ":signup-application.latest.2",
"command": [],
"environment": {},
"ports": {
"80": "HTTP"
}
}
},
"publicEndpoint": {
"containerName": "signup-app-container",
"containerPort": 80,
"healthCheck": {
"healthyThreshold": 2,
"unhealthyThreshold": 2,
"timeoutSeconds": 2,
"intervalSeconds": 5,
"path": "/",
"successCodes": "200-499"
}
},
"createdAt": "2021-07-17T18:40:58+02:00"
},
"nextDeployment": {
"version": 3,
"state": "ACTIVATING",
"containers": {
"signup-app-container": {
"image": ":signup-application.latest.1",
"command": [],
"environment": {},
"ports": {
"80": "HTTP"
}
}
},
"publicEndpoint": {
"containerName": "signup-app-container",
"containerPort": 80,
"healthCheck": {
"healthyThreshold": 2,
"unhealthyThreshold": 2,
"timeoutSeconds": 2,
"intervalSeconds": 5,
"path": "/",
"successCodes": "200-499"
}
},
"createdAt": "2021-07-17T19:40:42+02:00"
},
"isDisabled": false,
"principalArn": "arn:aws:iam::577312533299:role/amazon/lightsail/eu-west-3/containers/signup-application/1jetjd21p8qshe57seuh71tnrnn29ps77lnno20sbgl2ghbuc0r0",
"privateDomainName": "signup-application.service.local",
"url": "https://signup-application.me04fvc6dbk4e.eu-west-3.cs.amazonlightsail.com/"
}
}
經過片刻,部署 v3 (使用容器映像 v1) 呈現 ACTIVE 狀態。部署 v2 和 v1 為 INACTIVE。
您可確認第一個版本已經部署,作法是開啟瀏覽器,指向容器服務 URL。
