I made simple post making project based on Firebase. I save post into Firebase like this:
let data = UIImageJPEGRepresentation(newPostImageView.image!, 0.5)//Take photo from imageview
let metadata = FIRStorageMetadata()
metadata.contentType = "image/jpeg"//Define post image path
let postId = "\(currentUser.generalDetails.uid)\(NSUUID().uuidString)"//Generate postId
let imagePath = "postImages\(postId)/postPic.jpg"
storageRef.child(imagePath).put(data!, metadata: metadata) { (metadata, error) in
if error == nil {
let postRef = self.databaseRef.child("posts").childByAutoId()
let post = Post(postImageUrl: String(describing: metadata?.downloadURL()), profileImageUrl: self.currentUser.generalDetails.profileImageURL, postId: postId, content: self.newPostTextView.text, username: self.currentUser.generalDetails.userName)
postRef.setValue(post.toAnyObject())
}else {
print(error!.localizedDescription)
}
}
dismiss(animated: true, completion: nil)
currentUser.generalDetails. ...
currentUser.generalDetails. ...
is singleton I have.
"postImageUrl"
into Firebase like "Optional( https://firebasestorage.googleapis.com/v0/b/ "
I do not understand why, since I do not have optionals. Is image from imagePicker optional?
Try:-
let metaURLString = "\(metaData!.downloadURL())"
if metaURLString != "" {
let post = Post(postImageUrl: metaURLString, profileImageUrl: self.currentUser.generalDetails.profileImageURL, postId: postId, content: self.newPostTextView.text, username: self.currentUser.generalDetails.userName)
postRef.setValue(post.toAnyObject())
}
I think swift works best when using if let
to unwrap and test all needed preconditions for a block.
In this example you need an unwrapped image URL as a string that is not empty.
It's possible to set all of this up.
if let downloadUrl = metadata?.downloadURL() { // Unwrap the URL.
if let imageUrl = downloadUrl.absoluteString { // URL as a string.
if !imageUrl.isEmpty { // URL must not be empty.
}
}
}
Luckily, this can all be done on one line.
if let imageUrl = metadata?.downloadURL()?.absoluteString, !imageUrl.isEmpty {
}
Placed in context, this gives the following.
storageRef.child(imagePath).put(data!, metadata: metadata) { (metadata, error) in
if let imageUrl = metadata?.downloadURL()?.absoluteString, !imageUrl.isEmpty {
let postRef = self.databaseRef.child("posts").childByAutoId()
let post = Post(postImageUrl: imageUrl,
profileImageUrl: self.currentUser.generalDetails.profileImageURL,
postId: postId,
content: self.newPostTextView.text,
username: self.currentUser.generalDetails.userName)
postRef.setValue(post.toAnyObject())
} else if error != nil {
print(error!.localizedDescription)
} else {
print("Unknown error")
}
}
Finally, we can use a guard
statement to exit early. This reduces the level of indent in the main line of code.
storageRef.child(imagePath).put(data!, metadata: metadata) { (metadata, error) in
guard let imageUrl = metadata?.downloadURL()?.absoluteString, !imageUrl.isEmpty else {
print(error?.localizedDescription ?? "Unknown error")
return
}
let postRef = self.databaseRef.child("posts").childByAutoId()
let post = Post(postImageUrl: imageUrl,
profileImageUrl: self.currentUser.generalDetails.profileImageURL,
postId: postId,
content: self.newPostTextView.text,
username: self.currentUser.generalDetails.userName)
postRef.setValue(post.toAnyObject())
}
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