The current version is 2.0.1 and is available under the MIT licence. For more detail see the documentation reference page. Or see a minimal page that you could use as a basis for your own investigations.

Default Settings This plugin is designed to help overcome automated form submission by requiring a "real person" to identify text made up of dots. The entered value is compared on the server with the generated value to determine whether processing should continue. The real person functionality can easily be added to an input field with appropriate default settings.

You can also remove the real person functionality if it is no longer required. Default real person: Disable Remove $('#defaultReal').realperson(); $('#disableReal').click(function() { var disable = $(this).text() === 'Disable'; $(this).text(disable ? 'Enable' : 'Disable'); $('#defaultReal').realperson(disable ? 'disable' : 'enable'); }); $('#removeReal').click(function() { var destroy = $(this).text() === 'Remove'; $(this).text(destroy ? 'Re-attach' : 'Remove'); $('#defaultReal').realperson(destroy ? 'destroy' : {}); }); You can override the defaults globally as shown below: $.realperson.setDefaults({length: 5}); Processed fields are marked with a class of is_realperson and are not re-processed if targeted a second time.

Options Customise the real person functionality through additional settings. Different length: $('#lengthReal').realperson({length: 8}); Include numbers: $('#numberReal').realperson({chars: $.realperson.alphanumeric}); Regenerate instructions: $('#instructReal').realperson({regenerate: 'Try another'}); Change dots: $('#dotsReal').realperson({dot: 'o', dots: [[' * ', ' *** ', ' *** ', ' ** * ', ' ***** ', '** *', '** *'], ['****** ', '** *', '** *', '****** ', '** *', '** *', '****** '], [' ***** ', '** *', '** ', '** ', '** ', '** *', ' ***** '], ['****** ', '** *', '** *', '** *', '** *', '** *', '****** '], ['*******', '** ', '** ', '**** ', '** ', '** ', '*******'], ['*******', '** ', '** ', '**** ', '** ', '** ', '** '], [' ***** ', '** *', '** ', '** ', '** ***', '** *', ' ***** '], ['** *', '** *', '** *', '*******', '** *', '** *', '** *'], ['*******', ' ** ', ' ** ', ' ** ', ' ** ', ' ** ', '*******'], [' **', ' **', ' **', ' **', ' **', '* **', ' ***** '], ['** *', '** ** ', '**** ', '** ', '**** ', '** ** ', '** *'], ['** ', '** ', '** ', '** ', '** ', '** ', '*******'], ['* *', '** **', '*** * *', '** * *', '** *', '** *', '** *'], ['* *', '** *', '*** *', '** * *', '** * *', '** **', '** *'], [' ***** ', '** *', '** *', '** *', '** *', '** *', ' ***** '], ['****** ', '** *', '** *', '****** ', '** ', '** ', '** '], [' ***** ', '** *', '** *', '** *', '** * *', '** * ', ' **** *'], ['****** ', '** *', '** *', '****** ', '** * ', '** * ', '** *'], [' ***** ', '** *', '** ', ' ***** ', ' **', '* **', ' ***** '], ['*******', ' ** ', ' ** ', ' ** ', ' ** ', ' ** ', ' ** '], ['** *', '** *', '** *', '** *', '** *', '** *', ' ***** '], ['** *', '** *', ' ** * ', ' ** * ', ' *** ', ' *** ', ' * '], ['** *', '** *', '** *', '** * *', '*** * *', '** **', '* *'], ['** *', ' ** * ', ' *** ', ' * ', ' *** ', ' ** * ', '** *'], ['** *', ' ** * ', ' *** ', ' ** ', ' ** ', ' ** ', ' ** '], ['*******', ' ** ', ' ** ', ' ** ', ' ** ', '** ', '*******'], [' *** ', ' * * ', '* * *', '* * *', '* * *', ' * * ', ' *** '], [' * ', ' ** ', ' * * ', ' * ', ' * ', ' * ', '*******'], [' ***** ', '* *', ' *', ' * ', ' ** ', ' ** ', '*******'], [' ***** ', '* *', ' *', ' ** ', ' *', '* *', ' ***** '], [' * ', ' ** ', ' * * ', ' * * ', '*******', ' * ', ' * '], ['*******', '* ', '****** ', ' *', ' *', '* *', ' ***** '], [' **** ', ' * ', '* ', '****** ', '* *', '* *', ' ***** '], ['*******', ' * ', ' * ', ' * ', ' * ', ' * ', '* '], [' ***** ', '* *', '* *', ' ***** ', '* *', '* *', ' ***** '], [' ***** ', '* *', '* *', ' ******', ' *', ' * ', ' **** ']]});

Server-side Implementations To complete the form processing on the server, you compare the hash value computed from the text entered by the user with the hash value generated on the client. If the two match, then you have a "real person" submitting the form and can continue. The following server side implementations of the hash algorithm are available: PHP function rpHash($value) { $hash = 5381; $value = strtoupper($value); for($i = 0; $i < strlen($value); $i++) { $hash = (($hash << 5) + $hash) + ord(substr($value, $i)); } return $hash; } if (rpHash($_POST['realPerson'].salt) == $_POST['realPersonHash']) { // Accepted PHP - 64 bit function rpHash($value) { $hash = 5381; $value = strtoupper($value); for($i = 0; $i < strlen($value); $i++) { $hash = (leftShift32($hash, 5) + $hash) + ord(substr($value, $i)); } return $hash; } // Perform a 32bit left shift function leftShift32($number, $steps) { // convert to binary (string) $binary = decbin($number); // left-pad with 0's if necessary $binary = str_pad($binary, 32, "0", STR_PAD_LEFT); // left shift manually $binary = $binary.str_repeat("0", $steps); // get the last 32 bits $binary = substr($binary, strlen($binary) - 32); // if it's a positive number return it // otherwise return the 2's complement return ($binary{0} == "0" ? bindec($binary) : -(pow(2, 31) - bindec(substr($binary, 1)))); } if (rpHash($_POST['realPerson'].salt) == $_POST['realPersonHash']) { // Accepted Java private String rpHash(String value) { int hash = 5381; value = value.toUpperCase(); for(int i = 0; i < value.length(); i++) { hash = ((hash << 5) + hash) + value.charAt(i); } return String.valueOf(hash); } if (rpHash(request.getParameter("realPerson") + salt).equals( request.getParameter("realPersonHash"))) { // Accepted C# private string rpHash(string value) { int hash = 5381; value = value.ToUpper(); for (int i = 0; i < value.Length; i++) { hash = ((hash << 5) + hash) + value[i]; } return hash.ToString(); } if (rpHash(Request.Form["realPerson"] + salt) == Request.Form["realPersonHash"]) { // Accepted Cold Fusion Thanks to Emil Gudmundsson. <cffunction name="rpHash" access="public" returntype="string" output="false"> <cfargument name="capText" type="string" required="true" /> <cfset var theHash = 5381 /> <cfset var theValue = UCase(ARGUMENTS.capText) /> <cfloop from="1" to="#Len(Trim(theValue))#" index="i"> <cfset theHash = (bitSHLN(theHash,5) + theHash) + Asc(Mid(theValue,i,1)) /> </cfloop> <cfreturn theHash /> </cffunction> <cfif rpHash(FORM.realPerson) EQ FORM.realPersonHash> Accepted </cfif> Rails Thanks to S. Muellner. class FormController < BaseController # POST /form # POST /form.json def create realPerson = params[:realPerson] realPersonHash = params[:realPersonHash] if !realPerson.nil? && !realPersonHash.nil? && Integer(rpHash(realPerson)) == Integer(realPersonHash) # Accepted else # Rejected end end private def rpHash (defaultReal) hash = 5381 if !defaultReal.nil? defaultReal.upcase! defaultReal.length.times{ |i| hash = ((shift_32 hash, 5) + hash) + defaultReal[i].ord } end return hash end def shift_32 x, shift_amount shift_amount &= 0x1F x <<= shift_amount x &= 0xFFFFFFFF if (x & (1<<31)).zero? x else x - 2**32 end end end Python Thanks to Sérgio H. Berlotto Jr. import numpy as np #------------------------------ def rpHash(person): hash = 5381 value = person.upper() for caracter in value: hash = (( np.left_shift(hash, 5) + hash) + ord(caracter)) hash = np.int32(hash) #----------------------------- if rpHash(request.form['realPerson']) == request.form['realPersonHash']: # Accepted else: # Rejected

In the Wild This tab highlights examples of this plugin in use "in the wild". To add another example, please contact me (wood.keith{at}optusnet.com.au) and provide the plugin name, the URL of your site, its title, and a short description of its purpose and where/how the plugin is used.