RC Swift pod and codable

[paulb777]

Fix #6883 Remote Config Codable support

• Decode Remote Config Value
• Decode Config into a specified struct
• Set defaults via an encoded struct
• Added tests

This PR also does the following:

• Adds a subscript overload API (and tests) to get typed values from the top-level config API
• Initial Remote Config Swift library for CocoaPods and SwiftPM
• Migrate Swift tests to Swift directory
• Associate CI updates to build and test the new library in both CocoaPods and SwiftPM
• Convert Fake Console tests to use MockConfig from SharedTestUtils instead of a dummy GoogleService-Info.plist file
• Made Tests README.md more visible and include both types of Swift integration tests
• Consolidated test setup and Constants to APITestBase.swift and Constants.swift

Demonstration Quick Start PR at firebase/quickstart-ios#1332

Investigated Questions:

• Is there a better way to decode RemoteConfigValue's than modifying FirebaseDataEncoder.swift?
  • Not that we can find. RemoteConfigValue is an Objective C type. We don't want to decode to it, we want to decode to it to primitive types
• Are the subscript overload API's useful or are they too redundant with the decoder API's?
  • They're a useful abstraction and share the implementation with the RemoteConfigValue decoded implementation

Open Question:

• The decoder supports Date types, but it's not yet clear how that should work with RemoteConfig or other Firebase products.

Next Steps:

• API review(s) in progress - internally visible at go/firebase-rc-swift-type-safety

Thanks and congratulations to @fumito-ito for being a first mover in the RC Codable space with https://github.com/fumito-ito/SwiftyRemoteConfig! Any key additional features from that we should consider for adding here?

[google-oss-bot]

	1 Warning
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Generated by 🚫 Danger

[ncooke3]

Exciting stuff– thanks! I added some questions, comments, and suggestions.

[paulb777]

Thanks for the deep review @ncooke3 💯

[google-oss-bot]

Size Report ¹

Affected Products

• FirebaseDatabase

  Type	Base (c7456c9)	Merge (41741d0)	Diff
  CocoaPods	?	1.24 MB	? (?)

• FirebaseRemoteConfig

  Type	Base (c7456c9)	Merge (41741d0)	Diff
  CocoaPods	?	571 kB	? (?)

Test Logs

• Merge (41741d0): https://github.com/firebase/firebase-ios-sdk/actions/runs/1680178051

1. https://storage.googleapis.com/firebase-sdk-metric-reports/cueoRRrHP3.html

[google-oss-bot]

Coverage Report ¹

Affected Products

• FirebaseDatabase-iOS-FirebaseDatabase.framework

  Overall coverage changed from ? (c7456c9) to 56.74% (41741d0) by ?.

  102 individual files with coverage change

  Filename	Base (c7456c9)	Merge (41741d0)	Diff
  APLevelDB.mm	?	61.30%	?
  FAckUserWrite.m	?	83.33%	?
  FArraySortedDictionary.m	?	97.49%	?
  FAtomicNumber.m	?	100.00%	?
  fbase64.c	?	32.00%	?
  FCacheNode.m	?	100.00%	?
  FCachePolicy.m	?	17.14%	?
  FCancelEvent.m	?	0.00%	?
  FChange.m	?	88.24%	?
  FChildChangeAccumulator.m	?	62.32%	?
  FChildEventRegistration.m	?	0.00%	?
  FChildrenNode.m	?	90.40%	?
  FClock.m	?	100.00%	?
  FCompoundHash.m	?	97.70%	?
  FCompoundWrite.m	?	91.12%	?
  FConnection.m	?	26.09%	?
  FDataEvent.m	?	29.41%	?
  FEmptyNode.m	?	100.00%	?
  FEventEmitter.m	?	0.00%	?
  FEventGenerator.m	?	95.37%	?
  FEventRaiser.m	?	30.00%	?
  FImmutableSortedDictionary.m	?	31.03%	?
  FImmutableSortedSet.m	?	53.01%	?
  FImmutableTree.m	?	85.02%	?
  FIndex.m	?	91.67%	?
  FIndexedFilter.m	?	95.65%	?
  FIndexedNode.m	?	97.06%	?
  FIRDatabase.m	?	14.93%	?
  FIRDatabaseComponent.m	?	19.23%	?
  FIRDatabaseConfig.m	?	59.62%	?
  FIRDatabaseConnectionContextProvider.m	?	96.67%	?
  FIRDatabaseQuery.m	?	3.86%	?
  FIRDatabaseReference.m	?	6.41%	?
  FIRDataSnapshot.m	?	89.71%	?
  FIRMutableData.m	?	75.51%	?
  FIRRetryHelper.m	?	82.14%	?
  FIRServerValue.m	?	0.00%	?
  FIRTransactionResult.m	?	0.00%	?
  FKeepSyncedEventRegistration.m	?	0.00%	?
  FKeyIndex.m	?	60.56%	?
  FLeafNode.m	?	86.98%	?
  FLevelDBStorageEngine.m	?	72.66%	?
  FLimitedFilter.m	?	96.79%	?
  FListenComplete.m	?	0.00%	?
  FLLRBEmptyNode.m	?	75.00%	?
  FLLRBValueNode.m	?	84.83%	?
  FMaxNode.m	?	60.61%	?
  FMerge.m	?	87.18%	?
  FNamedNode.m	?	62.32%	?
  FNextPushId.m	?	62.00%	?
  FOperationSource.m	?	89.29%	?
  FOverwrite.m	?	81.48%	?
  FPath.m	?	93.86%	?
  FPathIndex.m	?	88.75%	?
  FPendingPut.m	?	0.00%	?
  FPersistenceManager.m	?	54.55%	?
  FPersistentConnection.m	?	20.95%	?
  FPriorityIndex.m	?	87.84%	?
  FPruneForest.m	?	93.08%	?
  FQueryParams.m	?	95.86%	?
  FQuerySpec.m	?	86.36%	?
  FRangedFilter.m	?	93.67%	?
  FRangeMerge.m	?	94.06%	?
  FRepo.m	?	13.42%	?
  FRepoInfo.m	?	73.00%	?
  FRepoManager.m	?	29.17%	?
  FServerValues.m	?	50.85%	?
  FSnapshotHolder.m	?	100.00%	?
  FSnapshotUtilities.m	?	60.45%	?
  FSparseSnapshotTree.m	?	97.20%	?
  FSRWebSocket.m	?	38.73%	?
  FStringUtilities.m	?	79.41%	?
  FSyncPoint.m	?	86.99%	?
  FSyncTree.m	?	70.73%	?
  FTrackedQuery.m	?	75.38%	?
  FTrackedQueryManager.m	?	90.00%	?
  FTransformedEnumerator.m	?	100.00%	?
  FTree.m	?	6.04%	?
  FTreeNode.m	?	100.00%	?
  FTreeSortedDictionary.m	?	95.79%	?
  FTreeSortedDictionaryEnumerator.m	?	100.00%	?
  FTupleNodePath.m	?	0.00%	?
  FTupleObjectNode.m	?	0.00%	?
  FTuplePathValue.m	?	100.00%	?
  FTupleRemovedQueriesEvents.m	?	100.00%	?
  FTupleSetIdPath.m	?	0.00%	?
  FTupleStringNode.m	?	0.00%	?
  FTupleTransaction.m	?	0.00%	?
  FTupleUserCallback.m	?	0.00%	?
  FUtilities.m	?	74.01%	?
  FValidation.m	?	25.58%	?
  FValueEventRegistration.m	?	0.00%	?
  FValueIndex.m	?	48.53%	?
  FView.m	?	78.98%	?
  FViewCache.m	?	100.00%	?
  FViewProcessor.m	?	90.86%	?
  FViewProcessorResult.m	?	100.00%	?
  FWebSocketConnection.m	?	41.91%	?
  FWriteRecord.m	?	45.65%	?
  FWriteTree.m	?	73.67%	?
  FWriteTreeRef.m	?	100.00%	?
  NSData+SRB64Additions.m	?	81.82%	?

• FirebaseRemoteConfig-iOS-FirebaseRemoteConfig.framework

  Overall coverage changed from ? (c7456c9) to 78.97% (41741d0) by ?.

  11 individual files with coverage change

  Filename	Base (c7456c9)	Merge (41741d0)	Diff
  FIRConfigValue.m	?	58.70%	?
  FIRRemoteConfig.m	?	83.44%	?
  FIRRemoteConfigComponent.m	?	97.06%	?
  RCNConfigContent.m	?	80.68%	?
  RCNConfigDBManager.m	?	75.95%	?
  RCNConfigExperiment.m	?	92.25%	?
  RCNConfigFetch.m	?	79.40%	?
  RCNConfigSettings.m	?	62.10%	?
  RCNDevice.m	?	81.29%	?
  RCNPersonalization.m	?	89.74%	?
  RCNUserDefaultsManager.m	?	97.89%	?

Test Logs

• Merge (41741d0): https://github.com/firebase/firebase-ios-sdk/actions/runs/1680178051

1. https://storage.googleapis.com/firebase-sdk-metric-reports/5qSOA0qbvf.html

[peterfriese]

Open Questions:

• Is there a better way to decode RemoteConfigValue's than modifying FirebaseDataEncoder.swift?
• Are the subscript overload API's useful or are they too redundant with the decoder API's?

Next Steps:

• Quickstart updates to demonstrate new APIs
• API review(s)
• Thanks and congratulations to @fumito-ito for being a first mover in the RC Codable space with https://github.com/fumito-ito/SwiftyRemoteConfig! Any key additional features from that we should consider for adding here?

Great stuff! Two questions / suggestions:

1. I think using "RemoteConfig" instead of "RC" as the prefix for the public facing types might be nicer, but that's my personal preference.
2. Any thoughts on adding a property wrapper for accessing remote config?

[ryanwilson]

Haven't looked at the test files yet, but here's the first pass before doing so.

[paulb777]

The API changes were approved today and I plan to merge on Tuesday.