Javascript 如何在云功能中从Firestore访问多个文档
我有一个在文档写入时触发的云函数。云函数需要根据触发器检查多个文档,并执行if/else语句 我创建了一个函数,该函数使用Promise.all访问所有文档,但如果还不可用,则在尝试访问所有文档信息时会出错Javascript 如何在云功能中从Firestore访问多个文档,javascript,angular,firebase,google-cloud-firestore,google-cloud-functions,Javascript,Angular,Firebase,Google Cloud Firestore,Google Cloud Functions,我有一个在文档写入时触发的云函数。云函数需要根据触发器检查多个文档,并执行if/else语句 我创建了一个函数,该函数使用Promise.all访问所有文档,但如果还不可用,则在尝试访问所有文档信息时会出错 export function onTriggered(change, context) { const userPrevData = change.before.data(); const userNewData = change.after.da
export function onTriggered(change, context) {
const userPrevData = change.before.data();
const userNewData = change.after.data();
const promises = [];
// Get the uid
const uid = context.params.userId;
// User DocRef
const userDoc = firestoreInstance.collection('users').doc(uid).get();
// User Session DocRef
const userSessionDoc = firestoreInstance.collection('sessions').doc(uid).get();
// Solution DocRef
const solutionDoc = firestoreInstance.collection('solution').doc('solutionId').get();
promises.push(userDoc, userSessionDoc, solutionDoc);
return Promise.all(promises).then((snapshots) => {
// Use Promise.all with snapshot.docs.map to combine+return Promise context
return Promise.all(snapshots.map((doc) => {
// At this point, each document and their Ids print to the console.
console.log('docId:::', doc.id);
console.log('docData:::', doc.data());
const solutionDocData = getSolutionDocData(doc);
// This will print as 'undefined' until the correct document data is processed
console.log('solutionDocData:::', solutionDocData);
// This will print as 'undefined' until the correct document data is processed
const clientSeed = doc.get('clientSeed');
// Check to see if the Users' Guess is the same as the solution
if (userNewData.guess.color === solutionDocData.guess.color && userNewData.guess.number === userNewData.guess.number) {
console.log('User solution is correct');
}
}));
})
}
function getSolutionDocData(doc) {
if (doc.id === 'solutionId') { return doc.data(); }
}
如果满足条件,我希望“用户解决方案是正确的”。但是,我得到一个错误,因为数据未定义。解决方案是移动大部分逻辑a。然后()
我不确定数据是否总是按照原始promise数组的顺序返回,因此我使用forEach语句来标识唯一属性并相应地分配它们。getSolutionDocData将在您向其传递id不是“solutionId”的文档时返回未定义的数据。这里没有足够的信息来理解这是否正确。@DougStevenson正如你所指出的,我也提到过,当信息不可用时,信息是未定义的。然而,问题中有足够的信息。解决方案是将逻辑移到.then语句中,在该语句中解析每个文档并执行逻辑。
return Promise.all(promises).then((snapshots) => {
// Use Promise.all with snapshot.docs.map to combine+return Promise context
return Promise.all(snapshots.map((doc) => {
// At this point, each document and their Ids print to the console.
console.log('docId:::', doc.id);
console.log('docData:::', doc.data());
return doc.data();
})).then(data => {
console.log('data:::', data);
let userDocDetails = {};
let userSessionDocDetails = {};
let solutionDocDetails = {};
data.forEach(document => {
if (document.uid === uid) { userDocDetails = document }
if (document.serverSeedEncrypted) { userSessionDocDetails = document }
if (document.solutionId) { solutionDocDetails = document }
});
});
})