解决AWS Amplify与DynamoDB数据不同步的问题,有以下几种方法:
const { DynamoDBStreams } = require('aws-sdk');
const { API } = require('aws-amplify');
const streamArn = 'YOUR_DYNAMODB_STREAM_ARN';
async function processRecords(records) {
for (const record of records) {
const {
eventName,
dynamodb: { NewImage, OldImage },
} = record;
// 根据事件类型进行相应的操作
if (eventName === 'INSERT' || eventName === 'MODIFY') {
const newData = DynamoDBStreams.Converter.unmarshall(NewImage);
// 使用AWS Amplify的API模块更新数据
await API.graphql({ query: /* your GraphQL mutation */, variables: { /* mutation variables */ } });
} else if (eventName === 'REMOVE') {
const oldData = DynamoDBStreams.Converter.unmarshall(OldImage);
// 使用AWS Amplify的API模块删除数据
await API.graphql({ query: /* your GraphQL mutation */, variables: { /* mutation variables */ } });
}
}
}
exports.handler = async (event) => {
const { Records } = event;
try {
await processRecords(Records);
return { statusCode: 200, body: 'Success' };
} catch (error) {
console.error(error);
return { statusCode: 500, body: 'Error' };
}
};
import { API, graphqlOperation } from 'aws-amplify';
// 创建一个GraphQL订阅
const subscription = API.graphql(graphqlOperation(/* your subscription query */, { /* subscription variables */ }));
// 监听订阅事件
subscription.subscribe({
next: (response) => {
const { data } = response;
// 处理订阅事件并更新AWS Amplify的数据
},
error: (error) => {
console.error(error);
},
});
import { API, graphqlOperation } from 'aws-amplify';
async function syncData() {
try {
// 查询DynamoDB表的更改
const changes = /* your code to query changes from DynamoDB */;
// 使用AWS Amplify的API模块更新数据
for (const change of changes) {
await API.graphql(graphqlOperation(/* your GraphQL mutation */, { /* mutation variables */ }));
}
} catch (error) {
console.error(error);
}
}
// 定期调用syncData函数
setInterval(syncData, /* your desired interval */);
这些方法可以根据您的具体需求选择适合您的解决方案。请注意,以上代码示例仅为参考,您需要根据实际情况进行相应的修改和调整。
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