2

I'm currently testing out AWS SAM with DynamoDB Local using Docker.

Here is the steps that I followed (mostly found in the internet)

  1. Create new docker network using docker network create local-dev.
  2. Run DynamoDB Local docker run -d -v "$PWD":/dynamodb_local_db -p 8000:8000 --network local-dev --name dynamodb amazon/dynamodb-local. Until this point, I'm being able to create and list tables using AWS CLI.
  3. Then, I proceed with running AWS SAM sam local start-api --docker-network local-dev. Everything looks okay.
  4. Invoked lambda.js, but it looks like no result for console.log(err)or console.log(data).

I'm not sure where could it be wrong. Please help me. Thank you in advance!

lambda.js

const services = require('./services.js');
const AWS = require('aws-sdk');

let options = {
    apiVersion: '2012-08-10',
    region: 'ap-southeast-1',
}

if(process.env.AWS_SAM_LOCAL) {
  options.endpoint = new AWS.Endpoint('http://localhost:8000')
}

const dynamoDB = new AWS.DynamoDB(options);

exports.getUser = async (event, context) => {

    let params = {};

    dynamoDB.listTables(params, (err, data) => {
        if(err) console.log(err)
            else console.log(data)
    })

    return true;
}

template.yaml

AWSTemplateFormatVersion: '2010-09-09'
Transform: AWS::Serverless-2016-10-31
Description: Serverless Resources


Parameters:

  FunctionsCodeBucket:
    Type: String
    Description: CodeBucket
  FunctionsCodeKey:
    Type: String
    Description: CodeKey
  FunctionsCodeVersion:
    Type: String
    Description: CodeVersion
  NodeEnv:
    Type: String
    Description: NodeEnv

Globals:
  Api:
    Cors:
      AllowMethods: "'OPTIONS,POST,GET,DELETE,PUT'"
      AllowHeaders: "'Content-Type,X-Amz-Date,Authorization,X-Api-Key,X-Amz-Security-Token,Api-Key,api-key'"
      AllowOrigin: "'*'"
  Function:
    Timeout: 300
    Runtime: nodejs10.x
    MemorySize: 128
    CodeUri: ./ 

Resources:
  DevResources:
    Type: AWS::Serverless::Function 
    Properties:                      
      Handler: "index.routes"
      Environment:
        Variables:
          NODE_ENV: !Ref NodeEnv
          # REGION: !Ref "AWS::Region"

      Policies:
      - Version: '2012-10-17'
        Statement:
        - Action:
          - dynamodb:*
          Effect: Allow
          Resource: "*"
      Events:
        GetUser:
          Type: Api 
          Properties:
            Path: /user
            Method: get
4

1 回答 1

2

您的 lambda 函数不等待dynamoDB.listTables操作。您可以使用以下的承诺版本来解决此问题dynamoDB.listTables：

exports.getUser = async (event, context) => {

  let params = {};

  try {
    const resp = await dynamoDB.listTables(params).promise();
    console.log(resp);
  } catch (err) {
    console.log(err)
  }
};

您可能需要做的另一件事是为您的 dynamodb 容器分配一个网络别名（您可以使用--network-alias=<container_name>选项来执行此操作），例如，让我们将别名设置为dynamodb

docker run -d -v "$PWD":/dynamodb_local_db -p 8000:8000 --network local-dev --network-alias=dynamodb --name dynamodb amazon/dynamodb-local

之后，您可以在 lambda 函数中使用此网络别名：

if(process.env.AWS_SAM_LOCAL) {
  options.endpoint = new AWS.Endpoint('http://dynamodb:8000')
}
于 2019-11-13T14:58:00.063 回答