How to disable Facebook codeless events programmatically?

Question

Problem

We've had a live app for months that worked fine, and then suddenly this code broke:

ViewController.swift

self.tableView.delegate = self.viewModel.tableViewHandler

which used this code

Broken code

component.swift

public override weak var delegate: UITableViewDelegate? {
     get { return super.delegate }
     set {
         if let del = newValue as? TableViewDelegateProxy {
             super.delegate = del
         } else if let del = super.delegate as? TableViewDelegateProxy {
             del.targetDelegate = newValue
         } else {
             super.delegate = newValue
         }
     }
 }

We couldn't figure out why, but we fixed it with this code:

Fixed code

ViewController.swift

self.tableView.fixedDelegate = self.viewModel.tableViewHandler

component.swift

// IMPORTANT NOTE: That is the correct way to set a delegate,
//                 otherwise overriding `delegate` property fails
public var fixedDelegate: UITableViewDelegate? {
    get { return self.delegate }
    set {
        self.delegateProxy.targetDelegate = newValue
        self.delegate = self.delegateProxy
    }
}

Initially we thought it was a problem from the backend (malformed JSON or something like that), but then we realized the following:

• broken code works when compiled using debug configuration, but breaks when using release configuration
• fixed code works when compiled using debug configuration and also works when using release configuration

We jumped back many releases in our Git history, and the same was always true, which is making us believe that there may have been some change to our Xcode or Objc/Swift runtime libraries which is causing this weirdness.

Question

What can be changing in our Xcode IDE to explain this? Can it be something that is changing remotely or behind the scenes? How can we further debug this?

References

1) Xcode version: Version 10.1 (10B61)
2) Swift version:

xcrun swift -version
Apple Swift version 4.2.1 (swiftlang-1000.11.42 clang-1000.11.45.1)
Target: x86_64-apple-darwin18.2.0

3) obj-c libraries:

 otool -L /usr/lib/libobjc.A.dylib
/usr/lib/libobjc.A.dylib:
        /usr/lib/libobjc.A.dylib (compatibility version 1.0.0, current version 228.0.0)
        /usr/lib/libc++abi.dylib (compatibility version 1.0.0, current version 400.17.0)
        /usr/lib/libc++.1.dylib (compatibility version 1.0.0, current version 400.9.4)
        /usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1252.200.5)

---

Update

First see this answer, we need to turn off this flag programmatically

_serverConfiguration.isCodelessEventsEnabled

not sure how from the sdk (Android or iOS)

What we have tried

1) we couldn't find any way of doing this through the FB SDKs, such as this one: https://developers.facebook.com/docs/reference/androidsdk/current/facebook/com/facebook/facebooksdk.html/

2) we tried to reverse engineer contacting the FB APIs via curl, it worked for scenarios like email:

curl --header "Content-Type: application/json" \
  --request POST \
  --data '{"app_events_feature_bitmask":0}' \
  "https://graph.facebook.com/***?access_token=<app_secret>"

which returned this

{"success":true}

but for app events feature nothing changed:

curl -i -X GET "https://graph.facebook.com/***?fields=app_events_feature_bitmask&access_token=<app_secret>"

it returns the old value:

{"app_events_feature_bitmask":37,"id":"***"}

3) ask FB tech support

Answer 1

It turns out this is some facebook remote config thing, if we comment out this code:

  //  UITableView
  void (^tableViewBlock)(UITableView *tableView,
                         SEL cmd,
                         id<UITableViewDelegate> delegate) =
  ^(UITableView *tableView, SEL cmd, id<UITableViewDelegate> delegate) {
    if (!delegate) {
      return;
    }

    [self matchView:tableView delegate:delegate];
  };
  [FBSDKSwizzler swizzleSelector:@selector(setDelegate:)
                         onClass:[UITableView class]
                       withBlock:tableViewBlock
                           named:@"match_table_view"];

It works just fine. This feature seems to turn on once this flag is turned on:

#if !TARGET_OS_TV
- (void)enableCodelessEvents {
  if (_serverConfiguration.isCodelessEventsEnabled) { <-----
    if (!_eventBindingManager) {
      _eventBindingManager = [[FBSDKEventBindingManager alloc] init];
    }

    if ([FBSDKInternalUtility isUnity]) {
      [FBSDKAppEvents sendEventBindingsToUnity];
    } else {
      [_eventBindingManager updateBindings:[FBSDKEventBindingManager
                                            parseArray:_serverConfiguration.eventBindings]];
    }
  }
}
#endif

the question is: what turned on this flag? (ie from some fb remote config)

_serverConfiguration.isCodelessEventsEnabled

that's what we're trying to find out

update: short answer: you cannot (programmatically, via dashboard, or even by contacting fb support themselves)

Facebook tech support got back to me stating in plain english that this option is simply not possible:

So long story short: by installing FB App Events SDK you will automatically turn on the FB remote config that enables Codeless Events and there is no way to turn it off.

Conclusion

We were able to reproduce the problem (specifically, turning on fb remote events flag by doing several steps on the facebook admin)

first run a sample app and test if the flag is on/off:

go to events manager and click on + add new data source > app events

when you click on that button you'll see this

and that's when the flag is turned on!