问题描述
我正在尝试将数据从 csv 文件迁移到现有的 AWS DynamoDB 表中，作为 AWS Amplify 网络应用程序的一部分。
我遵循了 this CloudFormation tutorial，使用以下模板。
我只能创建一个新的 DynamoDB 表，但不能使用现有表并向其添加数据。
问题： 有没有办法修改模板，以便我可以在向导的“指定堆栈详细信息”步骤中的“DynamoDBTableName”下提供现有表名，以便将 csv 数据添加到表中？如果没有，是否有替代流程？
{
"AWstemplateFormatVersion": "2010-09-09","Metadata": {
},"Parameters" : {
"BucketName": {
"Description": "Name of the S3 bucket you will deploy the CSV file to","Type": "String","ConstraintDescription": "must be a valid bucket name."
},"FileName": {
"Description": "Name of the S3 file (including suffix)","ConstraintDescription": "Valid S3 file name."
},"DynamoDBTableName": {
"Description": "Name of the dynamoDB table you will use","ConstraintDescription": "must be a valid dynamoDB name."
}
},"Resources": {
"DynamoDBTable":{
"Type": "AWS::DynamoDB::Table","Properties":{
"TableName": {"Ref" : "DynamoDBTableName"},"BillingMode": "PAY_PER_REQUEST","AttributeDeFinitions":[
{
"AttributeName": "id","AttributeType": "S"
}
],"KeySchema":[
{
"AttributeName": "id","KeyType": "HASH"
}
],"Tags":[
{
"Key": "Name","Value": {"Ref" : "DynamoDBTableName"}
}
]
}
},"LambdaRole" : {
"Type" : "AWS::IAM::Role","Properties" : {
"AssumeRolePolicyDocument": {
"Version" : "2012-10-17","Statement" : [
{
"Effect" : "Allow","Principal" : {
"Service" : ["lambda.amazonaws.com","s3.amazonaws.com"]
},"Action" : [
"sts:AssumeRole"
]
}
]
},"Path" : "/","ManagedPolicyArns":["arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole","arn:aws:iam::aws:policy/AWSLambdaInvocation-DynamoDB","arn:aws:iam::aws:policy/AmazonS3ReadOnlyAccess"],"Policies": [{
"PolicyName": "policyname","PolicyDocument": {
"Version": "2012-10-17","Statement": [{
"Effect": "Allow","Resource": "*","Action": [
"dynamodb:PutItem","dynamodb:BatchWriteItem"
]
}]
}
}]
}
},"CsvToDDBLambdaFunction": {
"Type": "AWS::Lambda::Function","Properties": {
"Handler": "index.lambda_handler","Role": {
"Fn::GetAtt": [
"LambdaRole","Arn"
]
},"Code": {
"ZipFile": {
"Fn::Join": [
"\n",[
"import json","import boto3","import os","import csv","import codecs","import sys","","s3 = boto3.resource('s3')","dynamodb = boto3.resource('dynamodb')","bucket = os.environ['bucket']","key = os.environ['key']","tableName = os.environ['table']","def lambda_handler(event,context):"," #get() does not store in memory"," try:"," obj = s3.Object(bucket,key).get()['Body']"," except:"," print(\"S3 Object Could not be opened. Check environment variable. \")"," table = dynamodb.Table(tableName)"," print(\"Error loading DynamoDB table. Check if table was created correctly and environment variable.\")"," batch_size = 100"," batch = []"," #DictReader is a generator; not stored in memory"," for row in csv.DictReader(codecs.getreader('utf-8-sig')(obj)):"," if len(batch) >= batch_size:"," write_to_dynamo(batch)"," batch.clear()"," batch.append(row)"," if batch:"," write_to_dynamo(batch)"," return {"," 'statusCode': 200,"," 'body': json.dumps('Uploaded to DynamoDB Table')"," }","def write_to_dynamo(rows):"," table = dynamodb.Table(tableName)"," print(\"Error loading DynamoDB table. Check if table was created correctly and environment variable.\")"," with table.batch_writer() as batch:"," for i in range(len(rows)):"," batch.put_item("," Item=rows[i]"," )"," print(\"Error executing batch_writer\")"
]
]
}
},"Runtime": "python3.7","Timeout": 900,"MemorySize": 3008,"Environment" : {
"Variables" : {"bucket" : { "Ref" : "BucketName" },"key" : { "Ref" : "FileName" },"table" : { "Ref" : "DynamoDBTableName" }}
}
}
},"S3Bucket": {
"DependsOn" : ["CsvToDDBLambdaFunction","BucketPermission"],"Type": "AWS::S3::Bucket","Properties": {
"BucketName": {"Ref" : "BucketName"},"AccessControl": "BucketownerFullControl","NotificationConfiguration":{
"LambdaConfigurations":[
{
"Event":"s3:ObjectCreated:*","Function":{
"Fn::GetAtt": [
"CsvToDDBLambdaFunction","Arn"
]
}
}
]
}
}
},"BucketPermission":{
"Type": "AWS::Lambda::Permission","Properties":{
"Action": "lambda:InvokeFunction","FunctionName":{"Ref" : "CsvToDDBLambdaFunction"},"Principal": "s3.amazonaws.com","SourceAccount": {"Ref":"AWS::AccountId"}
}
}
},"Outputs" : {
}
}
另一个答案
Dennis 的回答是一种解决方案，但您也可以注释掉 JSON 文件 "DynamoDBTable" 中的 "Resources" 部分。
解决方法
您可以使用 AWS Database Migration Service (DMS) 将 CSV 文件从 Amazon S3 迁移到 Amazon DynamoDB。看看这个step-by step walkthrough。