Initializes the attached file, temporary and permanent storage.

Calls #attach_cached, but skips if value is an empty string (this is useful when the uploaded file comes from form fields). Forwards any additional options to #attach_cached.

attacher.assign(File.open(...))
attacher.assign(File.open(...), metadata: { "foo" => "bar" })

# ignores the assignment when a blank string is given
attacher.assign("")

Uploads given IO object and changes the uploaded file.

# uploads the file to permanent storage
attacher.attach(io)

# uploads the file to specified storage
attacher.attach(io, storage: :other_store)

# forwards additional options to the uploader
attacher.attach(io, upload_options: { "x-amz-acl": "public-read" }, metadata: { "foo" => "bar" })

# removes the attachment
attacher.attach(nil)

Sets an existing cached file, or uploads an IO object to temporary storage and sets it via #attach. Forwards any additional options to #attach.

# upload file to temporary storage and set the uploaded file.
attacher.attach_cached(File.open(...))

# foward additional options to the uploader
attacher.attach_cached(File.open(...), metadata: { "foo" => "bar" })

# sets an existing cached file from JSON data
attacher.attach_cached("{\"id\":\"...\",\"storage\":\"cache\",\"metadata\ ":{...}}")

# sets an existing cached file from Hash data
attacher.attach_cached({ "id" => "...", "storage" => "cache", "metadata" => {} })

Returns whether a file is attached.

attacher.attach(io)
attacher.attached? #=> true

attacher.attach(nil)
attacher.attached? #=> false

Returns whether the file is uploaded to temporary storage.

attacher.cached?       # checks current file
attacher.cached?(file) # checks given file

Sets the uploaded file with dirty tracking, and runs validations.

attacher.change(uploaded_file)
attacher.file #=> #<Shrine::UploadedFile>
attacher.changed? #=> true

Returns whether the attachment has changed.

attacher.changed? #=> false
attacher.attach(file)
attacher.changed? #=> true

TODO This will work incorrect if @previous is nil

Returns options that are automatically forwarded to the uploader. Can be modified with additional data.

Generates serializable data for the attachment.

attacher.data #=> { "id" => "...", "storage" => "...", "metadata": { ... } }

Destroys the attachment.

attacher.file.exists? #=> true
attacher.destroy
attacher.file.exists? #=> false

Destroys the attached file if it exists and is uploaded to permanent storage.

attacher.file.exists? #=> true
attacher.destroy_attached
attacher.file.exists? #=> false

If a new file was attached, deletes previously attached file if any.

previous_file = attacher.file
attacher.attach(file)
attacher.destroy_previous
previous_file.exists? #=> false

Returns the attached uploaded file.

Returns attached file or raises an exception if no file is attached.

Returns the attached uploaded file.

Deletes any previous file and promotes newly attached cached file. It also clears any dirty tracking.

# promoting cached file
attacher.assign(io)
attacher.cached? #=> true
attacher.finalize
attacher.stored?

# deleting previous file
previous_file = attacher.file
previous_file.exists? #=> true
attacher.assign(io)
attacher.finalize
previous_file.exists? #=> false

# clearing dirty tracking
attacher.assign(io)
attacher.changed? #=> true
attacher.finalize
attacher.changed? #=> false

Returns the attached file.

# when a file is attached
attacher.get #=> #<Shrine::UploadedFile>

# when no file is attached
attacher.get #=> nil

Loads the uploaded file from data generated by Attacher#data.

attacher.file #=> nil
attacher.load_data({ "id" => "...", "storage" => "...", "metadata" => { ... } })
attacher.file #=> #<Shrine::UploadedFile>

Uploads current file to permanent storage and sets the stored file.

attacher.cached? #=> true
attacher.promote
attacher.stored? #=> true

If a new cached file has been attached, uploads it to permanent storage. Any additional options are forwarded to #promote.

attacher.assign(io)
attacher.cached? #=> true
attacher.promote_cached
attacher.stored? #=> true

Sets the uploaded file.

attacher.set(uploaded_file)
attacher.file #=> #<Shrine::UploadedFile>
attacher.changed? #=> false

Returns the Shrine class that this attacher's class is namespaced under.

Returns whether the file is uploaded to permanent storage.

attacher.stored?       # checks current file
attacher.stored?(file) # checks given file

Delegates to Shrine.upload, passing the #context.

# upload file to specified storage
attacher.upload(io, "store") #=> #<Shrine::UploadedFile>

# pass additional options for the uploader
attacher.upload(io, "store", metadata: { "foo" => "bar" })

Converts JSON or Hash data into a Shrine::UploadedFile object.

attacher.uploaded_file("{\"id\":\"...\",\"storage\":\"...\",\"metadata\":{...}}")
#=> #<Shrine::UploadedFile ...>

attacher.uploaded_file({ "id" => "...", "storage" => "...", "metadata" => {} })
#=> #<Shrine::UploadedFile ...>

If a file is attached, returns the uploaded file URL, otherwise returns nil. Any options are forwarded to the storage.

attacher.file = file
attacher.url #=> "https://..."

attacher.file = nil
attacher.url #=> nil