Realtime Firestore query results in error for "docChanges"

[Thkasis]

[REQUIRED] Describe your environment

• Operating System version: Windows, Google Chrome
• Firebase SDK version: 5.0.1
• Firebase Product: Firestore

Simple query for realtime onSnapshot() results in error when trying to work with snapshot.docChanges.
I don't see any doc.docChanges defined as it was in the previous version (4.9.1) that I was using and I get this error:
snapshot.docChanges.forEach is not a function. Logging snapshot.docChanges is not an array of changes as it was before and instead shows the prototype method.

Steps to reproduce:

Simply query data either using get() or realtime onSnapshot() similar to Firestore documents.

For realtime query:

firebase.firestore(firebase.app("ProjectFirst")).collection('test').where("flg", "==", "i").onSnapshot(function(snapshot) {
//there is data in database and I see them using get() method for instance
snapshot.docChanges.forEach(function(change) {
...
});
});

when I log snapshot.docChanges I see this instead of the array of results :

ƒ (e){validateOptionNames("QuerySnapshot.docChanges",e,["includeMetadataChanges"]),e&&validateNamedOptionalType("QuerySnapshot.docChanges","boolean","includeMetadataChanges",e.includeMetadataChanges);v…

[mikelehen]

@Thkasis Sorry for the trouble! We changed docChanges into a method in 5.0.0 so you must now do snapshot.docChanges() instead of snapshot.docChanges. You can find more details in our release notes here: https://firebase.google.com/support/release-notes/js#5.0.0

Thanks and sorry!

[Thkasis]

@mikelehen, not a problem, thanks for the update. It would definitely be helpful to have this in the documentation instead if it's supposed to be the standard from now on as documentation still shows docChanges.forEach()

Thanks for all the good work.
Cheers

[mikelehen]

Thank you! I see that indeed https://firebase.google.com/docs/firestore/query-data/listen still has the old syntax. Whoops! We'll get that updated shortly. Thanks for mentioning it.

[samtstern]

@Thkasis updating the docs right now, thanks!

[mohshraim]

@mikelehen
As this discuss the documentation i suggest also to add the new feature
.get({source:'cache'})
.get({source:'server'})

[samtstern]

@mohshraim yep we will add this to the docs soon, sorry about the delay!

[myleftshoe]

@google-cloud/firestore 0.16.1 has the opposite problem - snapshot.docChanges() errors with docChanges is not a function so I'm using snapshot.docChanges instead!

[mikelehen]

cc/ @schmidt-sebastian

[schmidt-sebastian]

PR for @google-cloud/firestore pending: googleapis/nodejs-firestore#324

This will make docChanges() a method in all of our JavaScript-based SDKs.

[elchefuser]

it seems they came back to a property , for me just works like docChanges, without parenthesis

[mikelehen]

@elchefuser It should still be a method. Which npm module are you using and what version?