aws-sdk-goでDynamoDBを取り扱うサンプル

テーブルのセット

この３つの項目で構成する

• userid number
• priolity number
• description string

PUT

package main

import (
	"fmt"

	"github.com/aws/aws-sdk-go/aws"
	"github.com/aws/aws-sdk-go/aws/session"
	"github.com/aws/aws-sdk-go/service/dynamodb"
)

func main() {
	ddb := dynamodb.New(session.New(), aws.NewConfig().WithRegion("ap-northeast-1"))

	param1 := &dynamodb.PutItemInput{
		TableName: aws.String("testdynamo"),
		Item: map[string]*dynamodb.AttributeValue{
			"userid": {
				N: aws.String("2"), //number
			},
			"priolity": {
				N: aws.String("100"), //number
			},
			"description": {
				S: aws.String("aiueo"), //string
			},
		},
	}

	result, err := ddb.PutItem(param1)
	if err != nil {
		fmt.Println(err)
	}
	fmt.Println(result)
}

GET

package main

import (
	"fmt"

	"github.com/aws/aws-sdk-go/aws"
	"github.com/aws/aws-sdk-go/aws/session"
	"github.com/aws/aws-sdk-go/service/dynamodb"
)

func main() {
	ddb := dynamodb.New(session.New(), aws.NewConfig().WithRegion("ap-northeast-1"))

	input := &dynamodb.GetItemInput{
		TableName: aws.String("testdynamo"),

		Key: map[string]*dynamodb.AttributeValue{
			"userid": {
				N: aws.String("2"),
			},
		},
		AttributesToGet: []*string{
			aws.String("userid"),
			aws.String("description"),
		},
		ConsistentRead: aws.Bool(true),

		ReturnConsumedCapacity: aws.String("NONE"),
	}

	resp, err := ddb.GetItem(input)
	if err != nil {
		fmt.Println(err)
	}

	fmt.Println(*resp.Item["userid"].N, *resp.Item["description"].S)
}

Query

package main

import (
	"fmt"

	"github.com/aws/aws-sdk-go/aws"
	"github.com/aws/aws-sdk-go/aws/session"
	"github.com/aws/aws-sdk-go/service/dynamodb"
)

func main() {
	ddb := dynamodb.New(session.New(), aws.NewConfig().WithRegion("ap-northeast-1"))

	input := &dynamodb.QueryInput{
		TableName: aws.String("testdynamo"),
		ExpressionAttributeNames: map[string]*string{
			"#userid": aws.String("userid"),
		},
		ExpressionAttributeValues: map[string]*dynamodb.AttributeValue{
			":userid": {
				N: aws.String("2"),
			},
		},
		KeyConditionExpression: aws.String("#userid = :userid"),
	}

	result, err := ddb.Query(input)
	if err != nil {
		fmt.Println(err)
	}
	fmt.Println(result)
}

scan

• FilterExpression: でフィルタができる
• 少量のデータ出れば、scanして手元でいじったほうが早そうではある

package main

import (
	"fmt"

	"github.com/aws/aws-sdk-go/aws"
	"github.com/aws/aws-sdk-go/aws/session"
	"github.com/aws/aws-sdk-go/service/dynamodb"
)

func main() {
	ddb := dynamodb.New(session.New(), aws.NewConfig().WithRegion("ap-northeast-1"))

	input := &dynamodb.ScanInput{
		TableName: aws.String("testdynamo2"),
		ExpressionAttributeNames: map[string]*string{
			"#userid":   aws.String("userid"),
			"#priolity": aws.String("priolity"),
		},
		ProjectionExpression: aws.String("#userid, #priolity"),
	}

	result, err := ddb.Scan(input)
	if err != nil {
		fmt.Println(err)
	}

	fmt.Println(result)
}