概要
表題通り、Node.jsでDynamoDBを操作する記事です。
基本情報
操作TBL
ディレクトリ構成
~/develop/study/aws/node/dynamo $ tree
.
├── crud
│ ├── OlympicCreateItem.js
│ ├── OlympicDeleteItem.js
│ ├── OlympicGetItem.js
│ └── OlympicUpdateItem.js
├── data
│ └── olympicData.json
└── migration
├── OlympicCreateTable.js
└── OlympicLoadData.js
3 directories, 7 files
事前準備
TBL作成(OlympicCreateTable.js)
var AWS = require("aws-sdk");
AWS.config.update({
region: "ap-northeast-1"
});
var dynamodb = new AWS.DynamoDB();
var params = {
TableName : "Olympic",
KeySchema: [
{ AttributeName: "Id", KeyType: "HASH"}, //Partition key
{ AttributeName: "Country", KeyType: "RANGE" } //Sort key
],
AttributeDefinitions: [
{ AttributeName: "Id", AttributeType: "N" },
{ AttributeName: "Country", AttributeType: "S" }
],
ProvisionedThroughput: {
ReadCapacityUnits: 10,
WriteCapacityUnits: 10
}
};
dynamodb.createTable(params, function(err, data) {
if (err) {
console.error("TBL作成失敗：", JSON.stringify(err, null, 2));
} else {
console.log("TBL作成成功：", JSON.stringify(data, null, 2));
}
});
olympicData.json
[
{
"Id": 1,
"Country": "日本",
"Medal": {
"GoldMedal": 11,
"SilverMedal": 11,
"BronzeMedal": 11
}
},
{
"Id": 2,
"Country": "アメリカ",
"Medal": {
"GoldMedal": 10,
"SilverMedal": 8,
"BronzeMedal": 7
}
},
{
"Id": 3,
"Country": "中国",
"Medal": {
"GoldMedal": 5,
"SilverMedal": 5,
"BronzeMedal": 5
}
}
]
TBL作成の実行結果
~/develop/study/aws/node/dynamo/migration $ node OlympicCreateTable.js
TBL作成成功： {
"TableDescription": {
"AttributeDefinitions": [
{
"AttributeName": "Country",
"AttributeType": "S"
},
{
"AttributeName": "Id",
"AttributeType": "N"
}
],
"TableName": "Olympic",
"KeySchema": [
{
"AttributeName": "Id",
"KeyType": "HASH"
},
{
"AttributeName": "Country",
"KeyType": "RANGE"
}
],
"TableStatus": "CREATING",
"CreationDateTime": "2021-07-29T10:20:05.059Z",
"ProvisionedThroughput": {
"NumberOfDecreasesToday": 0,
"ReadCapacityUnits": 10,
"WriteCapacityUnits": 10
},
"TableSizeBytes": 0,
"ItemCount": 0,
"TableArn": "arn:aws:dynamodb:ap-northeast-1:696770525325:table/Olympic",
"TableId": "5e5fb4bf-a314-496e-ad61-40387663f17f"
}
}
データのロード(OlympicLoadData.js)
var AWS = require("aws-sdk");
var fs = require('fs');
AWS.config.update({
region: "ap-northeast-1",
});
var docClient = new AWS.DynamoDB.DocumentClient();
console.log("データのロード開始");
var Countries = JSON.parse(fs.readFileSync('../data/olympicData.json', 'utf8'));
Countries.forEach(function(country) {
console.log(country)
var params = {
TableName: "Olympic",
Item: {
"Id": country.Id,
"Country": country.Country,
"Medal": country.Medal
}
};
docClient.put(params, function(err, data) {
if (err) {
console.error("ロード失敗", country.Id, ". Error JSON:", JSON.stringify(err, null, 2));
} else {
console.log("ロード成功:", country.Id + country.Country);
}
});
});
データのロード
~/develop/study/aws/node/dynamo/migration $ node OlympicLoadData.js
データのロード開始
{
Id: 1,
Country: '日本',
Medal: { GoldMedal: 11, SilverMedal: 11, BronzeMedal: 11 }
}
{
Id: 2,
Country: 'アメリカ',
Medal: { GoldMedal: 10, SilverMedal: 8, BronzeMedal: 7 }
}
{
Id: 3,
Country: '中国',
Medal: { GoldMedal: 5, SilverMedal: 5, BronzeMedal: 5 }
}
ロード成功: 3中国
ロード成功: 1日本
ロード成功: 2アメリカ
CREATE文
OlympicCreateItem.js
var AWS = require("aws-sdk");
AWS.config.update({
region: "ap-northeast-1",
});
var docClient = new AWS.DynamoDB.DocumentClient();
var table = "Olympic";
var params = {
TableName:table,
Item:{
"Id": 4,
"Country": "ドイツ",
"Medal": {
"GoldMedal": 7,
"SilverMedal": 7,
"BronzeMedal": 7
}
}
};
docClient.put(params, function(err, data) {
if (err) {
console.error("Unable to add item. Error JSON:", JSON.stringify(err, null, 2));
} else {
console.log("Added item");
}
});
READ文
OlympicGetItem.js
var AWS = require("aws-sdk");
AWS.config.update({
region: "ap-northeast-1",
});
var docClient = new AWS.DynamoDB.DocumentClient();
var table = "Olympic";
var params = {
TableName: table,
Key:{
"Id": 1,
"Country": '日本'
}
};
docClient.get(params, function(err, data) {
console.log(params)
console.log(data)
if (err) {
console.error("Unable to read item. Error JSON:", JSON.stringify(err, null, 2));
} else {
console.log("GetItem succeeded:", JSON.stringify(data, null, 2));
}
});
UPDATE文
OlympicUpdateItem.js
var AWS = require("aws-sdk");
AWS.config.update({
region: "ap-northeast-1",
});
var docClient = new AWS.DynamoDB.DocumentClient()
var table = "Olympic";
var params = {
TableName:table,
Key:{
"Id": 1,
"Country": '日本'
},
UpdateExpression: "set Medal.GoldMedal = :g",
ExpressionAttributeValues:{
":g":17,
},
ReturnValues:"UPDATED_NEW"
};
console.log("Updating the item...");
docClient.update(params, function(err, data) {
if (err) {
console.error("Unable to update item. Error JSON:", JSON.stringify(err, null, 2));
} else {
console.log("UpdateItem succeeded:", JSON.stringify(data, null, 2));
}
});
DELETE文
OlympicDeleteItem.js
var AWS = require("aws-sdk");
AWS.config.update({
region: "ap-northeast-1"
});
var docClient = new AWS.DynamoDB.DocumentClient();
var table = "Olympic";
var params = {
TableName:table,
Key:{
"Id": 4,
"Country": 'ドイツ'
},
};
console.log("Attempting a conditional delete...");
docClient.delete(params, function(err, data) {
if (err) {
console.error("Unable to delete item. Error JSON:", JSON.stringify(err, null, 2));
} else {
console.log("DeleteItem succeeded:", JSON.stringify(data, null, 2));
}
});
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