带有API网关的AWS Lambda

在上一篇文章中，我向您展示了如何创建和部署AWS Lambda。我们将继续这项工作，并只考虑更新该lambda的代码。我们还将使用AWS API Gateway将REST端点添加到AWS Lambda。

因此，在继续之前……（如果尚未使用），请按照上一篇文章中的说明进行操作，以确保您具有正在运行的AWS Lambda实例。

步骤1：更新您的Lambda

将以下内容粘贴到update-lambda.sh

#!/bin/bash### Create the lambda package
zip -j helloworld.zip *.pyfunction_name="helloworld"
package_file=helloworld.zip### Update the lambda code
aws lambda update-function-code \--function-name $function_name \--zip-file fileb://$package_file

或Java

#!/bin/bash### Create the lambda package
mvn packagefunction_name="helloworld"
package_file="target/lambda-java-example-1.0-SNAPSHOT.jar"### Update the lambda code
aws lambda update-function-code \--function-name $function_name \--zip-file fileb://$package_file

使脚本可执行文件chmod +x update-lambda.sh并更新lambda ./update-lambda.sh 。

第2步：传递一些东西给您的lambda

现在，我们知道了如何更新云中的lambda，让我们进行更改，以便我们可以将某些内容作为参数传递。与其说“你好，世界！” 我们希望它向任何人问好。

在Python中：

def lambda_handler(event, context):return "Hello {}!".format(event['to'])

或类似于Java中的以下内容：

package example;import com.amazonaws.services.lambda.runtime.Context;public class Hello {public String lambdaHandler(Request request, Context context) {return "Hello " + request.getTo() + "!";}
}class Request {private String to;public void setTo(String to) { this.to = to; }public String getTo() { return to; }
}

步骤3：告诉Lambda与任何人打招呼

aws lambda invoke --invocation-type RequestResponse --function-name helloworld --payload '{"to": "whomever"}' output.txt

你应该看到谁你好！ 在输出文本中

步骤4：让我们添加其余的API

将以下脚本粘贴到诸如create-api.sh的文件中，更改该文件的执行权限，然后执行该脚本。深吸一口气……

注意：此脚本期望定义AWS_REGION和AWS_ACCOUNT_ID环境变量

#!/bin/bash
set -eregion=$AWS_REGION
account_id=$AWS_ACCOUNT_IDecho "Creating a new API and capturing it's ID ..."
api_id=$(aws apigateway create-rest-api \--name HelloWorldAPI \--description "Hello World API" \--output text \--query 'id')
echo "> API ID is: $api_id"echo "Storing the API ID on disk - we'll need it later ..."
echo $api_id > api_id.txtecho "Geting the root resource id for the API ..."
root_id=$(aws apigateway get-resources \--rest-api-id "${api_id}" \--output text \--query 'items[?path==`'/'`].[id]')
echo root_id=$root_idecho "Creating a resource for the /hello path"
resource_id=$(aws apigateway create-resource \--rest-api-id "${api_id}" \--parent-id "${root_id}" \--path-part hello | jq -r .id) 
echo "Resource id is $resource_id"echo "Creating the GET method on the /hello resource"
aws apigateway put-method \--rest-api-id "${api_id}" \--resource-id "${resource_id}" \--http-method GET \--authorization-type NONE echo "Integrating the GET method to lambda. Note that the request tempalate uses API Gateway template language to pull in the query parameters as a JSON event for the lambda."
aws apigateway put-integration \--rest-api-id "${api_id}" \--resource-id "${resource_id}" \--http-method GET \--type AWS \--request-templates '{ "application/json": "{\n  #foreach($param in $input.params().querystring.keySet())\n    \"$param\": \"$util.escapeJavaScript($input.params().querystring.get($param))\" \n   #end\n  }" }' \--integration-http-method POST \--uri arn:aws:apigateway:${region}:lambda:path/2015-03-31/functions/arn:aws:lambda:${region}:${account_id}:function:helloworld/invocationsecho "Creating a default response for the GET method"
aws apigateway put-method-response \--rest-api-id "${api_id}" \--resource-id "${resource_id}" \--http-method GET \--status-code 200 echo "Creating a default response for the integration"
aws apigateway put-integration-response \--rest-api-id "${api_id}" \--resource-id "${resource_id}" \--http-method GET \--status-code 200 \--selection-pattern ".*"echo "Adding permission for the API to call the lambda for test so we can use the console to make the api call"
aws lambda add-permission \--function-name helloworld \--statement-id apigateway-helloworld-get-test \--action lambda:InvokeFunction \--principal apigateway.amazonaws.com \--source-arn "arn:aws:execute-api:${region}:${account_id}:${api_id}/*/GET/hello"echo "Adding permission for the API to call the lambda from any HTTP client"
aws lambda add-permission \--function-name helloworld \--statement-id apigateway-helloworld-get \--action lambda:InvokeFunction \--principal apigateway.amazonaws.com \--source-arn "arn:aws:execute-api:${region}:${account_id}:${api_id}/api/GET/hello"echo "Creating a deployment"
aws apigateway create-deployment \--rest-api-id "${api_id}" \--stage-name api echo "All done! you can invoke the api on https://${api_id}.execute-api.${region}.amazonaws.com/api/hello?to=whomever"

步骤5：调用API

脚本的最后输出提供了可以粘贴到浏览器中的URL。您应该看到“你好，你好！”的回答。一旦您点击进入浏览器。

步骤6：清理

您可以使用上delete.sh创建的delete.sh脚本删除lambda。删除api：粘贴以下脚本并照常执行。

#!/bin/bash
echo "Reading API id that I store in my create-api script"
api_id=$(<api_id.txt)echo "Removing the permissions from the lambda"
aws lambda remove-permission \--function-name helloworld \--statement-id apigateway-helloworld-get
aws lambda remove-permission \--function-name helloworld \--statement-id apigateway-helloworld-get-testecho "Deleting the API"
aws apigateway delete-rest-api \--rest-api-id "${api_id}"