JavaScript API — Uploading Files
Uploadcare File Uploader and JavaScript API work with file instances, which implement the jQuery promise interface. You can create a file instance via a new upload or by addressing existing files.
- Creating a new file instance
- Wait until a file is available
- Checking the progress of a file upload
- Cancelling a file upload
- Object overview,
fileInfo
- Object overview,
uploadInfo
Creating a new file instance
A new file instance can be constructed by calling the fileFrom
function. Where
the first argument is one of the predefined identifiers, and the second argument
holds a file source. Depending on the passed identifier, the function can start
a new upload or return an instance of an existing file.
Note, you can also pass a settings
object to
fileFrom
as its third parameter.
File instance from URL
Uploading a file from URL is done by passing the url
identifier to the
fileFrom
function:
var file = uploadcare.fileFrom('url', 'http://example.com/image.png');
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File instance from native object
Our JavaScript API supports uploading new files from
native file objects. This is done by passing the
object
identifier to the fileFrom
function.
var file = uploadcare.fileFrom('object', input.files[0]);
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This method supports large file uploads (> 100MB) and checking upload progress. However, it will not work in outdated browsers, see browser support.
File instance from DOM
You can also upload files from input DOM elements. This is done by passing the
input
identifier to fileFrom
. Uploading from such inputs works in all browsers
but does not support large files and checking upload progress.
var file = uploadcare.fileFrom('input', input);
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File instance from UUID or CDN URL
That is the case when a file instance is created from an existing file that has
a UUID and hence a CDN URL. Any of those can be used as a file source in
fileFrom
. The proper identifier to pass to the function, here, is uploaded
:
var file = uploadcare.fileFrom('uploaded', '61783708-7090-4d6a-b82b-81f98e40a327');
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Wait until a file is available
Quite often, you want to ensure a file is there and ready before getting its instance. That is what the function is all about. It returns a fileInfo object.
file.done(function(fileInfo) {
// Upload has successfully completed and a file is ready.
}).fail(function(error, fileInfo) {
// Upload failed, or something else went wrong, a file is not ready.
});
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The error
argument in the fail
callback is one of the following values,
or a user-defined custom value, raised via validators.
'baddata'
, invalid argument passed to file constructor'size'
, file size is too large'upload'
, error during upload'user'
, upload was canceled'info'
, error when fetching file information'deleted'
, file was deleted, also applicable to groups and files within
Checking the progress of a file upload
When handling larger files, there is a sense in checking their upload progress.
The progress
function does exactly that and returns an
uploadInfo object.
file.progress(function(uploadInfo) {
// State of your upload gets updated.
// The callback is invoked at least once with a current state,
// right after assignment.
});
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You can also show a file uploading progress via a jQuery UI progressbar.
file.progress(function(uploadInfo) {
$('#progress').progressbar('value', uploadInfo.progress);
});
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Cancelling a file upload
Just use cancel
in case you want to immediately stop any in-progress upload and
all the events.
file.cancel();
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Object overview, fileInfo
Here is how a fileInfo
object is structured,
Property | Type | Value |
---|---|---|
| string | File UUID. |
| string | Original filename. |
| number | File size in bytes. |
| boolean |
|
| boolean |
|
| string | Public CDN URL related to a file, may contain processing operations. |
| string | A string holding existing URL modifiers, i.e. processing operations in case those are present. Null otherwise. |
| string | Original file CDN URL with no modifiers. |
| object | Object holding original image properties, if your file is an image,
null otherwise. Properties:
|
| object | Object holding the info about a file source. For example, this can be a name of a social media, public URL, etc. We do not store such information hence it is only available on the page where your file uploading happens. |
Object overview, uploadInfo
Here is how an uploadInfo
object is structured,
Property | Type | Value |
---|---|---|
| string | Current upload states: |
| number | Upload progress as a value ranging from 0 to 1. |
| number | File ready state combines the progress of both upload and preparing info, as a value ranging from 0 to 1. |