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Storage - File Metadata

File Metadata​

After uploading a file to Firebase Storage reference, you can also get the file metadata, for example to view or update the content type. Files can also store custom key/value pairs with additional file metadata.

Get File Metadata​

File metadata contains common properties such as name, size, and contentType (often referred to as MIME type) in addition to some less common ones like contentDisposition and timeCreated. This metadata can be retrieved from a Firebase Storage reference using the getMetadata() method.

var reference:StorageReference = FirebaseStorage.service.getReference().child( "images/test.png" );
reference.getMetadata();

This will dispatch one of two events when the process is complete,

  • StorageReferenceEvent.GET_METADATA_SUCCESS: if metadata was successfully retrieved
  • StorageReferenceEvent.GET_METADATA_ERROR: if there was an error
reference.addEventListener( StorageReferenceEvent.GET_METADATA_SUCCESS, getMetadata_successHandler );
reference.addEventListener( StorageReferenceEvent.GET_METADATA_ERROR, getMetadata_errorHandler );
function getMetadata_successHandler( event:StorageReferenceEvent ):void 
{
    // getMetadata success
}

function getMetadata_errorHandler( event:StorageReferenceEvent ):void 
{
    // getMetadata error
    trace( event.errorMessage );
}

Get Download Url​

If you wish to retrieve a download URL to share the file you can call the getDownloadUrl() function which will asynchronously retrieve a long lived download URL with a revokable token. This can be used to share the file with others, but can be revoked by a developer in the Firebase Console if desired.

reference.getDownloadUrl();

This will dispatch one of two events when the process is complete,

  • StorageReferenceEvent.GET_DOWNLOAD_URL_SUCCESS: if url was successfully retrieved
  • StorageReferenceEvent.GET_DOWNLOAD_URL_ERROR: if there was an error
reference.addEventListener( StorageReferenceEvent.GET_DOWNLOAD_URL_SUCCESS, getDownloadUrl_successHandler );
reference.addEventListener( StorageReferenceEvent.GET_DOWNLOAD_URL_ERROR, getDownloadUrl_errorHandler );
function getDownloadUrl_successHandler( event:StorageReferenceEvent ):void 
{
    // getDownloadUrl success
    trace( event.url );
}

function getDownloadUrl_errorHandler( event:StorageReferenceEvent ):void 
{
    // getDownloadUrl error
    trace( event.errorMessage );
}