How to properly access a document object from Firestore using Cordova Firebase X in my Ionic app?

Issue

In my Ionic app, I apply FirebaseX plugin (https://github.com/dpa99c/cordova-plugin-firebasex) and use its method fetchDocumentInFirestoreCollection to access a document from my Firestore (assume the document does exist properly). It successfully passes the success callback function inside the method but the returned document object is never accessed. I don't know how to access it actually. Here are my two used approaches to access:

await this.firebase.fetchDocumentInFirestoreCollection(
          someDocID,
          'someCollection',
          () => {
            console.log('fetchFirestoreCollection successfully'); // this can be printed
          },
          error => {
            console.error('error in fetchFirestoreCollection', error);
          }
        ).then(
          doc => {
            // Not enter this block ever
            console.log(doc);
          }
        );

const doc = await this.firebase.fetchDocumentInFirestoreCollection(
          someDocID,
          'someCollection',
          () => {
            console.log('fetchFirestoreCollection successfully'); // this can be printed
          },
          error => {
            console.error('error in fetchFirestoreCollection', error);
          }
        );

But both of these two cannot access the returned document. How should I do?

Thank you.

Solution

In the @ionic-native/firebase-x/ngx/index.d.ts, change line 437 from

fetchDocumentInFirestoreCollection(documentId: string, collection: string, success: () => void, error: (err: string) => void): Promise<any>;

to

fetchDocumentInFirestoreCollection(documentId: string, collection: string, success: (value: object) => void, error: (err: string) => void): Promise<any>;

Answered By - M. G. Lincoln