Use Mailgun via javascript to validate e-mail addresses in submission forms.

opentech/apply/funds/templates/funds/application_base.html

@@ -42,3 +42,7 @@
     {% endif %}
 </div>
 {% endblock %}
+
+{% block extra_js %}
+    <script src="{% static 'js/apply/mailgun-validator.js' %}"></script>
+{% endblock %}

opentech/static_src/src/javascript/apply/mailgun-validator.js

+(function ($) {
+
+    'use strict';
+
+    $.fn.mailgunValidator = function (options) {
+        return this.each(function () {
+            var thisElement = $(this);
+            thisElement.focusout(function (e) {
+                // Trim string and autocorrect whitespace issues
+                var elementValue = thisElement.val();
+                elementValue = $.trim(elementValue);
+                thisElement.val(elementValue);
+
+                // Attach event to options
+                options.e = e;
+
+                run_validator(elementValue, options, thisElement);
+            });
+        });
+    };
+
+    function run_validator(address_text, options, element) {
+        // Abort existing AJAX Request to prevent flooding
+        if (element.mailgunRequest) {
+            element.mailgunRequest.abort();
+            element.mailgunRequest = null;
+        }
+
+        // don't run validator without input
+        if (!address_text) {
+            return;
+        }
+
+        // validator is in progress
+        if (options && options.in_progress) {
+            options.in_progress(options.e);
+        }
+
+        // don't run dupicate calls
+        if (element.mailgunLastSuccessReturn) {
+            if (address_text === element.mailgunLastSuccessReturn.address) {
+                if (options && options.success) {
+                    options.success(element.mailgunLastSuccessReturn, options.e);
+                }
+                return;
+            }
+        }
+
+        // length and @ syntax check
+        var success = false;
+        var error_message = false;
+        if (address_text.length > 512) {
+            error_message = 'Email address exceeds maxiumum allowable length of 512.';
+        }
+        else if (address_text.split('@').length - 1 !== 1) {
+            error_message = 'Email address must contain only one @.';
+        }
+
+        if (error_message) {
+            if (options && options.error) {
+                options.error(error_message, options.e);
+            }
+            return;
+        }
+
+        // timeout incase of some kind of internal server error
+        var timeoutID = setTimeout(function () {
+            error_message = 'Error occurred, unable to validate address.';
+            if (!success) {
+                // Abort existing AJAX Request for a true timeout
+                if (element.mailgunRequest) {
+                    element.mailgunRequest.abort();
+                    element.mailgunRequest = null;
+                }
+
+                if (options && options.error) {
+                    options.error(error_message, options.e);
+                }
+            }
+        }, 30000); // 30 seconds
+
+        // make ajax call to get validation results
+        element.mailgunRequest = $.ajax({
+            type: 'GET',
+            url: 'https://api.mailgun.net/v3/address/validate',
+            data: {
+                address: address_text,
+                api_key: options.api_key
+            },
+            dataType: 'jsonp',
+            crossDomain: true,
+            success: function (data, status_text) {
+                clearTimeout(timeoutID);
+
+                element.mailgunLastSuccessReturn = data;
+                if (options && options.success) {
+                    options.success(data, options.e);
+                }
+            },
+            error: function (request, status_text, error) {
+                clearTimeout(timeoutID);
+                error_message = 'Error occurred, unable to validate address.';
+
+                if (options && options.error) {
+                    options.error(error_message, options.e);
+                }
+            }
+        });
+    }
+
+    $('input[type=email]').each(function () {
+        $(this).after('<div class="status"></div>').mailgunValidator({
+            api_key: 'pubkey-b3ea454f53bcd621d767e64f0b4ef0ac',
+            error: validation_error
+        });
+    });
+
+    function validation_error(error_message) {
+        $('.status').html(error_message);
+    }
+
+})(jQuery);