Get data from firestore document and use in cloud function-CodePudding

In the user's collection, each user has a document with a customer_id. I would like to retrieve this customer_id and use it to create a setup intent.

The following code has worked for me in the past. However, all of a sudden it throws the error:

Object is possibly 'undefined'

The error is on the following line under snapshot.data() in this line:

const customerId = snapshot.data().customer_id;

Here is the entire code snippet:

exports.createSetupIntent = functions.https.onCall(async (data, context) => {
  const userId = data.userId;
  const snapshot = await db
      .collection("development")
      .doc("development")
      .collection("users")
      .doc(userId).get();
  const customerId = snapshot.data().customer_id;
  const setupIntent = await stripe.setupIntents.create({
    customer: customerId,
  });
  const clientSecret = setupIntent.client_secret;
  const intentId = setupIntent.id;
  return {
    clientsecret: clientSecret,
    intentId: intentId,
  };
});

Any help is appreciated :)

CodePudding user response：

this is because snapshot.data() may return undefined

there are 2 ways to solve this

first is assert as non-null, if you have high confident that the data exist

const customerId = snapshot.data()!.customer_id;

second if check for undefined

const customerId = snapshot.data()?.customer_id;

if(customerId){
  //  ....
}

I recommend the 2nd method, it is safer

CodePudding user response：

I can see you are using a sub collection order,You need to loop through the snapshot data using the forEach loop.


  const customerId = snapshot.data()
    customerId.forEach((id)=> {
       console.log(id.customer_id)
    });

Try this out but.

CodePudding user response：

The document you're trying to load may not exist, in which case calling data() on the snapshot will return null, and thus this line would give an error:

const customerId = snapshot.data().customer_id;

The solution is to check whether the document you loaded exists, and only then force to get the data from it:

if (snapshot.exists()) {
  const customerId = snapshot.data()!.customer_id;
  ...
}