[JAWS-UG CLI] Lambda:#15 canary (Python版)

前提条件
========


Lambdaへの権限
--------------

Lambdaに対してフル権限があること。


AWS CLI
-------

以下のバージョンで動作確認済

* AWS CLI 1.10.33
* AWS CLI 1.10.20

```bash:コマンド:
aws --version
```

```text:結果(例):

      aws-cli/1.10.20 Python/2.7.11 Darwin/15.4.0 botocore/1.4.11
```


IAM Role
--------

'lambdaBasicExecution'ロールが存在すること。

```bash:変数の設定:
IAM_ROLE_NAME='lambdaBasicExecution'
```

```bash:コマンド:
aws iam get-role \
   --role-name ${IAM_ROLE_NAME}
```

```json:結果(例):
      {
          "Role": {
            "AssumeRolePolicyDocument": {
                "Version": "2012-10-17",
                "Statement": [
                    {
                        "Action": "sts:AssumeRole",
                        "Principal": {
                            "Service": "lambda.amazonaws.com"
                        },
                        "Effect": "Allow",
                        "Sid": ""
                    }
                ]
            },
            "RoleId": "AROAXXXXXXXXXXXXXXXXX",
            "CreateDate": "2015-10-26T01:55:54Z",
            "RoleName": "lambdaBasicExecution",
            "Path": "/",
            "Arn": "arn:aws:iam::XXXXXXXXXXXX:role/lambdaBasicExecution"
          }
      }
```

存在しない場合は、
http://qiita.com/tcsh/items/455fcea33fc1171a5502
の手順に従って作成してください。


0. 準備
=======

## 0.1. リージョンの指定

```bash:変数の設定
export AWS_DEFAULT_REGION=ap-northeast-1
```

0.2. 変数の確認
---------------

プロファイルが想定のものになっていることを確認します。

```bash:変数の確認:
aws configure list
```

```text:結果(例):

            Name                    Value             Type    Location
            ----                    -----             ----    --------
         profile       lambdaFull-prjz-mbp13        env    AWS_DEFAULT_PROFILE
      access_key     ****************XXXX shared-credentials-file
      secret_key     ****************XXXX shared-credentials-file
          region        ap-northeast-1        env    AWS_DEFAULT_REGION
```


0.2. IAM RoleのARN取得
----------------------

```bash:変数の設定:
IAM_ROLE_NAME='lambdaBasicExecution'
```

```bash:コマンド:
IAM_ROLE_ARN=$( \
  aws iam get-role \
    --role-name ${IAM_ROLE_NAME} \
    --query 'Role.Arn' \
    --output text \
) \
  && echo ${IAM_ROLE_ARN}
```

```text:結果(例):
      arn:aws:iam::XXXXXXXXXXXX:role/lambdaBasicExecution
```


1. 事前作業
===========


1.1. Lambda関数名の決定
-----------------------

```bash:変数の設定:
LAMBDA_FUNC_NAME="canary-$( date '+%Y%m%d' )"
```

同名のLambda関数の不存在確認

```bash:コマンド:
aws lambda get-function \
  --function-name ${LAMBDA_FUNC_NAME}
```

```text:結果(例):

      A client error (ResourceNotFoundException) occurred when calling the GetFunction operation: Function not found: arn:aws:lambda:ap-northeast-1:XXXXXXXXXXXX:function:canary-20160425
```


1.2. Lambda関数
---------------

```bash:変数の設定:
FILE_LAMBDA_FUNC="${LAMBDA_FUNC_NAME}.py"
PY_FUNC_NAME='lambda_handler'
```

```bash:変数の確認:
cat << ETX

    FILE_LAMBDA_FUNC: ${FILE_LAMBDA_FUNC}
    PY_FUNC_NAME:     ${PY_FUNC_NAME}

ETX
```

2016-05-28時点で、blueprintのターゲット( 'https://www.amazon.com/' に'Online Shopping'があることをチェックする)そのままでは503エラーが出るので、 http://aws.amazon.com/jp/ に'AWS'があることをチェックするように修正してあります。( https://forums.aws.amazon.com/thread.jspa?threadID=232591 )

```bash:コマンド:
cat << EOF > ${FILE_LAMBDA_FUNC}
from __future__ import print_function

from datetime import datetime
from urllib2 import urlopen

SITE = 'https://aws.amazon.com/jp/'  # URL of the site to check
EXPECTED = 'AWS'  # String expected to be on the page


def validate(res):
    '''Return False to trigger the canary

    Currently this simply checks whether the EXPECTED string is present.
    However, you could modify this to perform any number of arbitrary
    checks on the contents of SITE.
    '''
    return EXPECTED in res


def ${PY_FUNC_NAME}(event, context):
    print('Checking {} at {}...'.format(SITE, event['time']))
    try:
        if not validate(urlopen(SITE).read()):
            raise Exception('Validation failed')
    except:
        print('Check failed!')
        raise
    else:
        print('Check passed!')
        return event['time']
    finally:
        print('Check complete at {}'.format(str(datetime.now())))
EOF

cat ${FILE_LAMBDA_FUNC}
```

```bash:コマンド:
zip ${LAMBDA_FUNC_NAME}.zip ${FILE_LAMBDA_FUNC}
```

```text:結果(例):

      adding: canary-20160425.py (deflated 43%)
```


2. Lambda関数の作成
===================

```bash:変数の設定:
LAMBDA_FUNC_DESC='Performs a periodic check of the given site, erroring out on test failure.'
LAMBDA_RUNTIME='python2.7'
LAMBDA_HANDLER="${LAMBDA_FUNC_NAME}.${PY_FUNC_NAME}"
FILE_LAMBDA_ZIP="${LAMBDA_FUNC_NAME}.zip"
```

```bash:変数の確認:
cat << ETX

  LAMBDA_FUNC_NAME:  ${LAMBDA_FUNC_NAME}
  LAMBDA_FUNC_DESC: "${LAMBDA_FUNC_DESC}"
  LAMBDA_RUNTIME:    ${LAMBDA_RUNTIME}
  FILE_LAMBDA_ZIP    ${FILE_LAMBDA_ZIP}
  IAM_ROLE_ARN:      ${IAM_ROLE_ARN}
  LAMBDA_HANDLER:    ${LAMBDA_HANDLER}

ETX
```

```bash:コマンド:
aws lambda create-function \
  --function-name ${LAMBDA_FUNC_NAME} \
  --description "${LAMBDA_FUNC_DESC}" \
  --zip-file fileb://${FILE_LAMBDA_ZIP} \
  --runtime ${LAMBDA_RUNTIME} \
  --role ${IAM_ROLE_ARN} \
  --handler ${LAMBDA_HANDLER}
```

```json:結果(例):

      {
        "CodeSha256": "WnGd6iPBS0rGCJor4zyuOaGBtzQ3I/OgHerXWqZzbL8=",
        "FunctionName": "canary-20160425",
        "CodeSize": 350,
        "MemorySize": 128,
        "FunctionArn": "arn:aws:lambda:ap-northeast-1:XXXXXXXXXXXX:function:canary-20160425",
        "Version": "$LATEST",
        "Role": "arn:aws:iam::XXXXXXXXXXXX:role/lambdaBasicExecution",
        "Timeout": 3,
        "LastModified": "2015-10-26T02:08:11.949+0000",
        "Handler": "canary-20160425.lambda_handler",
        "Runtime": "python2.7",
        "Description": "Performs a periodic check of the given site, erroring out on test failure."
      }
```

```bash:コマンド:
aws lambda list-functions 
```

```json:結果(例):

      {
          "Functions": [
            {
                "Version": "$LATEST",
                "CodeSha256": "WnGd6iPBS0rGCJor4zyuOaGBtzQ3I/OgHerXWqZzbL8=",
                "FunctionName": "canary-20160425",
                "MemorySize": 128,
                "CodeSize": 350,
                "FunctionArn": "arn:aws:lambda:ap-northeast-1:XXXXXXXXXXXX:function:canary-20160425",
                "Handler": "canary-20160425.lambda_handler",
                "Role": "arn:aws:iam::XXXXXXXXXXXX:role/lambdaBasicExecution",
                "Timeout": 3,
                "LastModified": "4月 25, 2016T02:08:11.949+0000",
                "Runtime": "python2.7",
                "Description": "Performs a periodic check of the given site, erroring out on test failure."
            }
          ]
      }
```

```bash:コマンド:
aws lambda get-function \
  --function-name ${LAMBDA_FUNC_NAME}
```

```json:結果(例):

      {
        "Code": {
          "RepositoryType": "S3",
          "Location": "https://awslambda-ap-ne-1-tasks.s3-ap-northeast-1.amazonaws.com/snapshots/XXXXXXXXXXXX/HelloWorld-2979ba79-b08f-495d-9ee6-46397c95ba13?x-amz-security-token=AQoDYXdzEDoa8AMR6t8h66eOXhN3%2Fx7XpuRxvf7pVn7IuWV4cEmwx0CtZT6yxCJ1%2BWmigYXqGoyQHuBYOWnxbhmwEcTg839qMuhSu1fk0fXpXf0oJOLkhKMudNqhdElyFQpzyT6Q8GDfhAsfbX9wvwCDTty4imxz7MczF%2FQl6tgvTYdip08ap5fAyrknZGV1%2B1Ggnp5w6JOjydYxuUsWwhoxoEWzi7SoVTmpRQQA91c4VW9lNotOAHACFxo6klzDPM8mxR9RJl66WxFugL0wQJyLUpmtjS9XoArD86sEWWiIccMpV2BQipTPQlzL%2F1Hoy%2BDF6QUxyPUihlDjPBoJTISTP8W1wxmzW%2BLbilAfFQRPY7CFjzR0k%2FA%2FIX5x9iyz52Pu1Q0ASTw1l%2Fq%2Fo3pRbvzWR79QS%2BpxXrwbYzoQHKiK62DSTsQo5tqKPsiDCYzrPxbq8lm7pNBPG%2FsxjePRWBVJeRl08WxEjSjoRRwBOPX5mz1BCUoUBPGG5tEENp87A%2FCdDgibFWM5DdYhwtaYPY7FTmi8DvqjQHL9jOmP8YuVteBTBcv8nFW6UbErPjwwn79FKG1u5M9HoTWUqUMBByz6D4tTRSEw6iJU7XdCujFnhnHe5V8imZ1KGI7fDWpciJhrhml0wnKPCK%2Fe9lK1P2kO7ldSWc7zn5hcIOD2tbEF&AWSAccessKeyId=ASIAJFVALOKV5SJVYPPA&Expires=1445825978&Signature=bvwu1Ny34LgTmZeOO3q4sn7x3Fg%3D"
        },
        "Configuration": {
          "Version": "$LATEST",
          "CodeSha256": "WnGd6iPBS0rGCJor4zyuOaGBtzQ3I/OgHerXWqZzbL8=",
          "FunctionName": "canary-20160425",
          "MemorySize": 128,
          "CodeSize": 350,
          "FunctionArn": "arn:aws:lambda:ap-northeast-1:XXXXXXXXXXXX:function:canary-20160425",
          "Handler": "canary-20160425.lambda_handler",
          "Role": "arn:aws:iam::XXXXXXXXXXXX:role/lambdaBasicExecution",
          "Timeout": 3,
          "LastModified": "2015-10-26T02:08:11.949+0000",
          "Runtime": "python2.7",
          "Description": "Performs a periodic check of the given site, erroring out on test failure."
        }
      }
```

```bash:コマンド:
aws lambda get-function-configuration \
  --function-name ${LAMBDA_FUNC_NAME}
```

```json:結果(例):

      {
        "CodeSha256": "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx=",
        "FunctionName": "canary-20160425",
        "CodeSize": 350,
        "MemorySize": 128,
        "FunctionArn": "arn:aws:lambda:ap-northeast-1:XXXXXXXXXXXX:function:canary-20160425",
        "Version": "$LATEST",
        "Role": "arn:aws:iam::XXXXXXXXXXXX:role/lambdaBasicExecution",
        "Timeout": 3,
        "LastModified": "2015-10-26T01:23:45.678+0000",
        "Handler": "canary-20160425.lambda_handler",
        "Runtime": "nodejs",
        "Description": "Performs a periodic check of the given site, erroring out on test failure."
      }
```


3. Lambda関数の動作確認
=======================


3.1. サンプルデータの作成
-------------------------

```bash:変数の設定:
FILE_INPUT="${LAMBDA_FUNC_NAME}-data.json" \
    && echo ${FILE_INPUT}
```

```bash:コマンド:
cat << EOF > ${FILE_INPUT}
{
  "account": "123456789012",
  "region": "${AWS_DEFAULT_REGION}",
  "detail": {},
  "detail-type": "Scheduled Event",
  "source": "aws.events",
  "time": "1970-01-01T00:00:00Z",
  "id": "cdc73f9d-aea9-11e3-9d5a-835b769c0d9c",
  "resources": [
    "arn:aws:events:${AWS_DEFAULT_REGION}:123456789012:rule/my-schedule"
  ]
}
EOF

cat ${FILE_INPUT}
```

JSONファイルを作成したら、フォーマットが壊れてないか必ず確認します。

```bash:コマンド:
jsonlint -q ${FILE_INPUT}
```

エラーが出力されなければOKです。


3.2. lambda関数の手動実行
-------------------------

```bash:変数の設定:
FILE_OUTPUT_LAMBDA="${LAMBDA_FUNC_NAME}-out.txt"
FILE_LOG_LAMBDA="${LAMBDA_FUNC_NAME}-$(date +%Y%m%d%H%M%S).log"
```

```bash:変数の確認:
cat << ETX

  LAMBDA_FUNC_NAME:   ${LAMBDA_FUNC_NAME}
  FILE_INPUT:         ${FILE_INPUT}
  FILE_OUTPUT_LAMBDA: ${FILE_OUTPUT_LAMBDA}
  FILE_LOG_LAMBDA:    ${FILE_LOG_LAMBDA}

ETX
```

```bash:コマンド:
aws lambda invoke \
  --function-name ${LAMBDA_FUNC_NAME} \
  --log-type Tail \
  --payload file://${FILE_INPUT} \
  ${FILE_OUTPUT_LAMBDA} \
  > ${FILE_LOG_LAMBDA}
```

```bash:コマンド:
cat ${FILE_LOG_LAMBDA} \
  | jp.py 'StatusCode'
```

```text:結果(例):

      200
```


3.3. lambda関数の実行結果の確認
-------------------------------

```bash:コマンド:
cat ${FILE_OUTPUT_LAMBDA}
```

```text:結果(例):
1970-01-01T00:00:00Z
```


3.4. lambda関数のログの確認
---------------------------

```bash:コマンド:
cat ${FILE_LOG_LAMBDA} \
  | jp.py 'LogResult' \
  | sed 's/"//g' \
  | base64 --decode
```

```text:結果(例):
START RequestId: 932b5962-0ac7-11e6-8702-2d4debfa833c Version: $LATEST
Checking https://www.amazon.com/ at 1970-01-01T00:00:00Z...
Check passed!
Check complete at 2016-04-25 09:24:57.698355
END RequestId: 932b5962-0ac7-11e6-8702-2d4debfa833c
REPORT RequestId: 932b5962-0ac7-11e6-8702-2d4debfa833c	Duration: 951.16 ms	Billed Duration: 1000 ms 	Memory Size: 128 MB	Max Memory Used: 17 MB	
```


完了
====