maxFileSize and acceptFileTypes in blueimp file upload plugin do not work. Why?

Had the same problem, and the blueimp guy says "maxFileSize and acceptFileTypes are only supported by the UI version" and has provided a (broken) link to incorporate the _validate and _hasError methods.

So without knowing how to incorporate those methods without messing up the script I wrote this little function. It seems to work for me.

Just add this

add: function(e, data) {
        var uploadErrors = [];
        var acceptFileTypes = /^image\/(gif|jpe?g|png)$/i;
        if(data.originalFiles[0]['type'].length && !acceptFileTypes.test(data.originalFiles[0]['type'])) {
            uploadErrors.push('Not an accepted file type');
        }
        if(data.originalFiles[0]['size'].length && data.originalFiles[0]['size'] > 5000000) {
            uploadErrors.push('Filesize is too big');
        }
        if(uploadErrors.length > 0) {
            alert(uploadErrors.join("\n"));
        } else {
            data.submit();
        }
},

at the start of the .fileupload options as shown in your code here

$(document).ready(function () {
    'use strict';

    $('#fileupload').fileupload({
        add: function(e, data) {
                var uploadErrors = [];
                var acceptFileTypes = /^image\/(gif|jpe?g|png)$/i;
                if(data.originalFiles[0]['type'].length && !acceptFileTypes.test(data.originalFiles[0]['type'])) {
                    uploadErrors.push('Not an accepted file type');
                }
                if(data.originalFiles[0]['size'].length && data.originalFiles[0]['size'] > 5000000) {
                    uploadErrors.push('Filesize is too big');
                }
                if(uploadErrors.length > 0) {
                    alert(uploadErrors.join("\n"));
                } else {
                    data.submit();
                }
        },
        dataType: 'json',
        autoUpload: false,
        // acceptFileTypes: /(\.|\/)(gif|jpe?g|png)$/i,
        // maxFileSize: 5000000,
        done: function (e, data) {
            $.each(data.result.files, function (index, file) {
                $('<p style="color: green;">' + file.name + '<i class="elusive-ok" style="padding-left:10px;"/> - Type: ' + file.type + ' - Size: ' + file.size + ' byte</p>')
                .appendTo('#div_files');
            });
        },
        fail: function (e, data) {
            $.each(data.messages, function (index, error) {
                $('<p style="color: red;">Upload file error: ' + error + '<i class="elusive-remove" style="padding-left:10px;"/></p>')
                .appendTo('#div_files');
            });
        },
        progressall: function (e, data) {
            var progress = parseInt(data.loaded / data.total * 100, 10);

            $('#progress .bar').css('width', progress + '%');
        }
    });
});

You'll notice I added a filesize function in there as well because that will also only work in the UI version.

Updated to get past issue suggested by @lopsided: Added data.originalFiles[0]['type'].length and data.originalFiles[0]['size'].length in the queries to make sure they exist and are not empty first before testing for errors. If they don't exist, no error will be shown and it will only rely on your server side error testing.

This works for me in firefox

$('#fileupload').fileupload({

    dataType: 'json',
    //acceptFileTypes: /(\.|\/)(xml|pdf)$/i,
    //maxFileSize: 15000000,

    add: function (e, data) {
        var uploadErrors = [];

        var acceptFileTypes = /\/(pdf|xml)$/i;
        if(data.originalFiles[0]['type'].length && !acceptFileTypes.test(data.originalFiles[0]['type'])) {
            uploadErrors.push('File type not accepted');
        }

        console.log(data.originalFiles[0]['size']) ;
        if (data.originalFiles[0]['size'] > 5000000) {
            uploadErrors.push('Filesize too big');
        }
        if(uploadErrors.length > 0) {
            alert(uploadErrors.join("\n"));
        } else {
            data.context = $('<p/>').text('Uploading...').appendTo(document.body);
            data.submit();
        }

    },
    done: function (e, data) {
        data.context.text('Success!.');
    }
});

You should include jquery.fileupload-process.js and jquery.fileupload-validate.js to make it work.

As suggested in an earlier answer, we need to include two additional files - jquery.fileupload-process.js and then jquery.fileupload-validate.js However as I need to perform some additional ajax calls while adding a file, I am subscribing to the fileuploadadd event to perform those calls. Regarding such a usage the author of this plugin suggested the following

Please have a look here: https://github.com/blueimp/jQuery-File-Upload/wiki/Options#wiki-callback-options

Adding additional event listeners via bind (or on method with jQuery 1.7+) method is the preferred option to preserve callback settings by the jQuery File Upload UI version.

Alternatively, you can also simply start the processing in your own callback, like this: https://github.com/blueimp/jQuery-File-Upload/blob/master/js/jquery.fileupload-process.js#L50

Using the combination of the two suggested options, the following code works perfectly for me

$fileInput.fileupload({
    url: 'upload_url',
    type: 'POST',
    dataType: 'json',
    autoUpload: false,
    disableValidation: false,
    maxFileSize: 1024 * 1024,
    messages: {
        maxFileSize: 'File exceeds maximum allowed size of 1MB',
    }
});

$fileInput.on('fileuploadadd', function(evt, data) {
    var $this = $(this);
    var validation = data.process(function () {
        return $this.fileupload('process', data);
    });

    validation.done(function() {
        makeAjaxCall('some_other_url', { fileName: data.files[0].name, fileSizeInBytes: data.files[0].size })
            .done(function(resp) {
                data.formData = data.formData || {};
                data.formData.someData = resp.SomeData;
                data.submit();
        });
    });
    validation.fail(function(data) {
        console.log('Upload error: ' + data.files[0].error);
    });
});