Uploading Files onto Firebase is skipping lines of code?

Question

I am relatively new to swift and Firebase but I am definitely encountering a weird problem. What seems to be happening after messing around in the debugger is that the following function seems to be exhibiting weird behavior such as skipping the line storageRef.put()

So whats been happening is this, this function is triggered when the user clicks on a save button. As I observe in the debugger, storageRef is called but the if else statements are never invoked. Then, after my function returns the object which wasn't properly initalized, it then returns into the if else statement with the proper values... By then it is too late as the value returned and uploaded to the database is already incorrect..

func toAnyObject() -> [String : Any] {
        beforeImageUrl = ""
        let storageRef = FIRStorage.storage().reference().child("myImage.png")
        let uploadData = UIImagePNGRepresentation(beforeImage!)
        storageRef.put(uploadData!, metadata: nil) { (metadata, error) in
            if (error != nil) {
                print(error)
            } else {
                self.beforeImageUrl = (metadata?.downloadURL()?.absoluteString)!
                print("upload complete: \(metadata?.downloadURL())")
            }
        }

        let firebaseJobObject : [String: Any] = ["jobType"          :  jobType! as Any,
                                                 "jobDescription"   :  jobDescription! as Any,
                                                 "beforeImageUrl"   :  beforeImageUrl! as Any,]
        return firebaseJobObject
    }

Answer 1

Consider a change in your approach here. The button target-action is typical of a solution that requires an immediate response.

However, when you involve other processes (via networks) like the - (FIRStorageUploadTask *)putData:(NSData *)uploadData method above, then you must use some form of delegation to perform the delayed action whenever the server side method returns a value.

Keep in mind that when you are trying to use the above method, that it is not meant for use with large files. You should use - (FIRStorageUploadTask *)putFile:(NSURL *)fileURL method.

I'd suggest that you rework the solution to ensure that the follow-up action only happens when the put succeeds or fails. Keep in mind that network traffic means that the upload could take some time. If you want to validate that the put is completing with a success or failure, just add a breakpoint at the appropriate location inside the completion block and run the method on a device with/and without network access (to test both code flows).