Cloud Storage for Firebase allows you to quickly and easily upload files to a
Cloud Storage
bucket provided
and managed by Firebase.
Create a Reference
To upload a file, first
create a Cloud Storage reference
to the location in Cloud Storage you want to upload the file to.
You can create a reference by appending child paths to the root of your
Cloud Storage bucket:
Swift
// Create a root reference
let storageRef = storage.reference()
// Create a reference to "mountains.jpg"
let mountainsRef = storageRef.child("mountains.jpg")
// Create a reference to 'images/mountains.jpg'
let mountainImagesRef = storageRef.child("images/mountains.jpg")
// While the file names are the same, the references point to different files
mountainsRef.name == mountainImagesRef.name // true
mountainsRef.fullPath == mountainImagesRef.fullPath // false
Objective-C
// Create a root reference
FIRStorageReference *storageRef = [storage reference];
// Create a reference to "mountains.jpg"
FIRStorageReference *mountainsRef = [storageRef child:@"mountains.jpg"];
// Create a reference to 'images/mountains.jpg'
FIRStorageReference *mountainImagesRef = [storageRef child:@"images/mountains.jpg"];
// While the file names are the same, the references point to different files
[mountainsRef.name isEqualToString:mountainImagesRef.name]; // true
[mountainsRef.fullPath isEqualToString:mountainImagesRef.fullPath]; // false
You cannot upload data with a reference to the root of your
Cloud Storage bucket. Your reference must point to a child URL.
Upload Files
Once you have a reference, you can upload files to Cloud Storage
in two ways:
- Upload from data in memory
- Upload from a URL representing a file on device
Upload from data in memory
The
putData:metadata:completion:
method is the simplest way to upload a file
to Cloud Storage.
putData:metadata:completion:
takes an NSData
object and returns an
FIRStorageUploadTask
, which you can use to manage your
upload and monitor its status.
Swift
// Data in memory
let data = Data()
// Create a reference to the file you want to upload
let riversRef = storageRef.child("images/rivers.jpg")
// Upload the file to the path "images/rivers.jpg"
let uploadTask = riversRef.putData(data, metadata: nil) { (metadata, error) in
guard let metadata = metadata else {
// Uh-oh, an error occurred!
return
}
// Metadata contains file metadata such as size, content-type.
let size = metadata.size
// You can also access to download URL after upload.
riversRef.downloadURL { (url, error) in
guard let downloadURL = url else {
// Uh-oh, an error occurred!
return
}
}
}
Objective-C
// Data in memory
NSData *data = [NSData dataWithContentsOfFile:@"rivers.jpg"];
// Create a reference to the file you want to upload
FIRStorageReference *riversRef = [storageRef child:@"images/rivers.jpg"];
// Upload the file to the path "images/rivers.jpg"
FIRStorageUploadTask *uploadTask = [riversRef putData:data
metadata:nil
completion:^(FIRStorageMetadata *metadata,
NSError *error) {
if (error != nil) {
// Uh-oh, an error occurred!
} else {
// Metadata contains file metadata such as size, content-type, and download URL.
int size = metadata.size;
// You can also access to download URL after upload.
[riversRef downloadURLWithCompletion:^(NSURL * _Nullable URL, NSError * _Nullable error) {
if (error != nil) {
// Uh-oh, an error occurred!
} else {
NSURL *downloadURL = URL;
}
}];
}
}];
Upload from a local file
You can upload local files on the devices, such as photos and videos from the
camera, with the
putFile:metadata:completion:
method.
putFile:metadata:completion:
takes an
NSURL
and returns an
FIRStorageUploadTask
, which you can use to manage your upload and monitor its
status.
Swift
// File located on disk
let localFile = URL(string: "path/to/image")!
// Create a reference to the file you want to upload
let riversRef = storageRef.child("images/rivers.jpg")
// Upload the file to the path "images/rivers.jpg"
let uploadTask = riversRef.putFile(from: localFile, metadata: nil) { metadata, error in
guard let metadata = metadata else {
// Uh-oh, an error occurred!
return
}
// Metadata contains file metadata such as size, content-type.
let size = metadata.size
// You can also access to download URL after upload.
riversRef.downloadURL { (url, error) in
guard let downloadURL = url else {
// Uh-oh, an error occurred!
return
}
}
}
Objective-C
// File located on disk
NSURL *localFile = [NSURL URLWithString:@"path/to/image"];
// Create a reference to the file you want to upload
FIRStorageReference *riversRef = [storageRef child:@"images/rivers.jpg"];
// Upload the file to the path "images/rivers.jpg"
FIRStorageUploadTask *uploadTask = [riversRef putFile:localFile metadata:nil completion:^(FIRStorageMetadata *metadata, NSError *error) {
if (error != nil) {
// Uh-oh, an error occurred!
} else {
// Metadata contains file metadata such as size, content-type, and download URL.
int size = metadata.size;
// You can also access to download URL after upload.
[riversRef downloadURLWithCompletion:^(NSURL * _Nullable URL, NSError * _Nullable error) {
if (error != nil) {
// Uh-oh, an error occurred!
} else {
NSURL *downloadURL = URL;
}
}];
}
}];
If you want to actively manage your upload, you can use the
putData:
or
putFile:
methods and observe the upload task, rather than using the
completion handler. See
Manage Uploads
for more
information.
You can also include metadata when you upload files.
This metadata contains typical file metadata properties such as
name
,
size
,
and
contentType
(commonly referred to as MIME type). The
putFile:
method
automatically infers the content type from the
NSURL
filename extension, but
you can override the auto-detected type by specifying
contentType
in the
metadata. If you do not provide a
contentType
and Cloud Storage
cannot infer a default from the file extension, Cloud Storage uses
application/octet-stream
. See the
Use File Metadata
section for more information about file metadata.
Swift
// Create storage reference
let mountainsRef = storageRef.child("images/mountains.jpg")
// Create file metadata including the content type
let metadata = StorageMetadata()
metadata.contentType = "image/jpeg"
// Upload data and metadata
mountainsRef.putData(data, metadata: metadata)
// Upload file and metadata
mountainsRef.putFile(from: localFile, metadata: metadata)
Objective-C
// Create storage reference
FIRStorageReference *mountainsRef = [storageRef child:@"images/mountains.jpg"];
// Create file metadata including the content type
FIRStorageMetadata *metadata = [[FIRStorageMetadata alloc] init];
metadata.contentType = @"image/jpeg";
// Upload data and metadata
FIRStorageUploadTask *uploadTask = [mountainsRef putData:data metadata:metadata];
// Upload file and metadata
uploadTask = [mountainsRef putFile:localFile metadata:metadata];
Manage Uploads
In addition to starting uploads, you can pause, resume, and cancel uploads using
the
pause
,
resume
, and
cancel
methods. These methods raise
pause
,
resume
, and
cancel
events. Canceling an upload causes the upload to fail
with an error indicating that the upload was canceled.
Swift
// Start uploading a file
let uploadTask = storageRef.putFile(from: localFile)
// Pause the upload
uploadTask.pause()
// Resume the upload
uploadTask.resume()
// Cancel the upload
uploadTask.cancel()
Objective-C
// Start uploading a file
FIRStorageUploadTask *uploadTask = [storageRef putFile:localFile];
// Pause the upload
[uploadTask pause];
// Resume the upload
[uploadTask resume];
// Cancel the upload
[uploadTask cancel];
Monitor Upload Progress
You can attach observers to
FIRStorageUploadTask
s in order to monitor the
progress of the upload. Adding an observer returns a
FIRStorageHandle
that can be used to remove the observer.
Swift
// Add a progress observer to an upload task
let observer = uploadTask.observe(.progress) { snapshot in
// A progress event occured
}
Objective-C
// Add a progress observer to an upload task
FIRStorageHandle observer = [uploadTask observeStatus:FIRStorageTaskStatusProgress
handler:^(FIRStorageTaskSnapshot *snapshot) {
// A progress event occurred
}];
These observers can be added to an
FIRStorageTaskStatus
event:
FIRStorageTaskStatus
Event
|
Typical Usage
|
FIRStorageTaskStatusResume
|
This event fires when the task starts or resumes uploading, and is often used in conjunction with the
FIRStorageTaskStatusPause
event.
|
FIRStorageTaskStatusProgress
|
This event fires any time data is uploading to Cloud Storage, and can be used to populate an upload progress indicator.
|
FIRStorageTaskStatusPause
|
This event fires any time the upload is paused, and is often used in conjunction with the
FIRStorageTaskStatusResume
event.
|
FIRStorageTaskStatusSuccess
|
This event fires when a upload has completed successfully.
|
FIRStorageTaskStatusFailure
|
This event fires when a upload has failed. Inspect the error to determine the failure reason.
|
When an event occurs, an
FIRStorageTaskSnapshot
object is passed back. This
snapshot is an immutable view of the task, at the time the event occurred.
This object contains the following properties:
Property
|
Type
|
Description
|
progress
|
NSProgress
|
An
NSProgress
object containing the progress of the upload.
|
error
|
NSError
|
An error that occurred during upload, if any.
|
metadata
|
FIRStorageMetadata
|
During upload contains metadata being uploaded. After an
FIRTaskStatusSuccess
event, contains the uploaded file's metadata.
|
task
|
FIRStorageUploadTask
|
The task this is a snapshot of, which can be used to manage (
pause
,
resume
,
cancel
) the task.
|
reference
|
FIRStorageReference
|
The reference this task came from.
|
You can also remove observers, either individually, by status, or by removing
all of them.
Swift
// Create a task listener handle
let observer = uploadTask.observe(.progress) { snapshot in
// A progress event occurred
}
// Remove an individual observer
uploadTask.removeObserver(withHandle: observer)
// Remove all observers of a particular status
uploadTask.removeAllObservers(for: .progress)
// Remove all observers
uploadTask.removeAllObservers()
Objective-C
// Create a task listener handle
FIRStorageHandle observer = [uploadTask observeStatus:FIRStorageTaskStatusProgress
handler:^(FIRStorageTaskSnapshot *snapshot) {
// A progress event occurred
}];
// Remove an individual observer
[uploadTask removeObserverWithHandle:observer];
// Remove all observers of a particular status
[uploadTask removeAllObserversForStatus:FIRStorageTaskStatusProgress];
// Remove all observers
[uploadTask removeAllObservers];
To prevent memory leaks, all observers are removed after an
FIRStorageTaskStatusSuccess
or
FIRStorageTaskStatusFailure
occurs.
Error Handling
There are a number of reasons why errors may occur on upload, including
the local file not existing, or the user not having permission to upload
the desired file. You can find more information about errors in the
Handle Errors
section of the docs.
Full Example
A full example of an upload with progress monitoring and error handling
is shown below:
Swift
// Local file you want to upload
let localFile = URL(string: "path/to/image")!
// Create the file metadata
let metadata = StorageMetadata()
metadata.contentType = "image/jpeg"
// Upload file and metadata to the object 'images/mountains.jpg'
let uploadTask = storageRef.putFile(from: localFile, metadata: metadata)
// Listen for state changes, errors, and completion of the upload.
uploadTask.observe(.resume) { snapshot in
// Upload resumed, also fires when the upload starts
}
uploadTask.observe(.pause) { snapshot in
// Upload paused
}
uploadTask.observe(.progress) { snapshot in
// Upload reported progress
let percentComplete = 100.0 * Double(snapshot.progress!.completedUnitCount)
/ Double(snapshot.progress!.totalUnitCount)
}
uploadTask.observe(.success) { snapshot in
// Upload completed successfully
}
uploadTask.observe(.failure) { snapshot in
if let error = snapshot.error as? NSError {
switch (StorageErrorCode(rawValue: error.code)!) {
case .objectNotFound:
// File doesn't exist
break
case .unauthorized:
// User doesn't have permission to access file
break
case .cancelled:
// User canceled the upload
break
/* ... */
case .unknown:
// Unknown error occurred, inspect the server response
break
default:
// A separate error occurred. This is a good place to retry the upload.
break
}
}
}
Objective-C
// Local file you want to upload
NSURL *localFile = [NSURL URLWithString:@"path/to/image"];
// Create the file metadata
FIRStorageMetadata *metadata = [[FIRStorageMetadata alloc] init];
metadata.contentType = @"image/jpeg";
// Upload file and metadata to the object 'images/mountains.jpg'
FIRStorageUploadTask *uploadTask = [storageRef putFile:localFile metadata:metadata];
// Listen for state changes, errors, and completion of the upload.
[uploadTask observeStatus:FIRStorageTaskStatusResume handler:^(FIRStorageTaskSnapshot *snapshot) {
// Upload resumed, also fires when the upload starts
}];
[uploadTask observeStatus:FIRStorageTaskStatusPause handler:^(FIRStorageTaskSnapshot *snapshot) {
// Upload paused
}];
[uploadTask observeStatus:FIRStorageTaskStatusProgress handler:^(FIRStorageTaskSnapshot *snapshot) {
// Upload reported progress
double percentComplete = 100.0 * (snapshot.progress.completedUnitCount) / (snapshot.progress.totalUnitCount);
}];
[uploadTask observeStatus:FIRStorageTaskStatusSuccess handler:^(FIRStorageTaskSnapshot *snapshot) {
// Upload completed successfully
}];
// Errors only occur in the "Failure" case
[uploadTask observeStatus:FIRStorageTaskStatusFailure handler:^(FIRStorageTaskSnapshot *snapshot) {
if (snapshot.error != nil) {
switch (snapshot.error.code) {
case FIRStorageErrorCodeObjectNotFound:
// File doesn't exist
break;
case FIRStorageErrorCodeUnauthorized:
// User doesn't have permission to access file
break;
case FIRStorageErrorCodeCancelled:
// User canceled the upload
break;
/* ... */
case FIRStorageErrorCodeUnknown:
// Unknown error occurred, inspect the server response
break;
}
}
}];
Now that you've uploaded files, let's learn how to
download them
from Cloud Storage.