Merge pull request #9 from aboudreault/answer-min-characters

Answer min characters

mentoring/answer.py

@@ -29,7 +29,7 @@ from lazy import lazy
 
 from xblock.fragment import Fragment
 
-from .light_children import LightChild, Boolean, Scope, String
+from .light_children import LightChild, Boolean, Scope, String, Integer
 from .models import Answer
 from .utils import render_template
 
@@ -51,6 +51,8 @@ class AnswerBlock(LightChild):
     read_only = Boolean(help="Display as a read-only field", default=False, scope=Scope.content)
     default_from = String(help="If specified, the name of the answer to get the default value from",
                           default=None, scope=Scope.content)
+    min_characters = Integer(help="Minimum number of characters allowed for the answer",
+                             default=0, scope=Scope.content)
 
     @lazy
     def student_input(self):
@@ -106,7 +108,11 @@ class AnswerBlock(LightChild):
 
     @property
     def completed(self):
-        return bool(self.read_only or self.student_input)
+        answer_length_ok = self.student_input
+        if self.min_characters > 0:
+            answer_length_ok = len(self.student_input.strip()) >= self.min_characters
+
+        return bool(self.read_only or answer_length_ok)
 
     def save(self):
         """

mentoring/mrq.py

@@ -43,8 +43,10 @@ class MRQBlock(QuestionnaireAbstractBlock):
     An XBlock used to ask multiple-response questions
     """
     student_choices = List(help="Last submissions by the student", default=[], scope=Scope.user_state)
-    max_attempts = Integer(help="Number of max attempts for this questions", scope=Scope.content)
-    num_attempts = Integer(help="Number of attempts a user has answered for this questions", scope=Scope.user_state)
+    max_attempts = Integer(help="Number of max attempts for this questions", default=0,
+                           scope=Scope.content)
+    num_attempts = Integer(help="Number of attempts a user has answered for this questions",
+                           default=0, scope=Scope.user_state)
 
     # TODO REMOVE THIS, ONLY NEEDED FOR LIGHTCHILDREN
     @classmethod

mentoring/public/js/answer.js

 function AnswerBlock(runtime, element) {
     return {
+
+        init: function(options) {
+          // register the child validator
+          $(':input', element).on('keyup', options.blockValidator);
+        },
+
         submit: function() {
-            return $(element).find(':input').serializeArray();
+            return $(':input', element).serializeArray();
         },
+
         handleSubmit: function(result) {
             $(element).find('.message').text((result || {}).error || '');
+        },
+
+        // Returns `true` if the child is valid, else `false`
+        validate: function() {
+            var input = $(':input', element),
+                input_value = input.val().replace(/^\s+|\s+$/gm,''),
+                answer_length = input_value.length,
+                data = input.data();
+
+            // an answer cannot be empty event if min_characters is 0
+            if (_.isNumber(data.min_characters)) {
+                var min_characters = _.max([data.min_characters, 1]);
+                if (answer_length < min_characters) {
+                    return false;
+                }
+            }
+
+            return true;
         }
     }
 }

mentoring/public/js/mentoring.js

@@ -77,6 +77,7 @@ function MentoringBlock(runtime, element) {
         var submit_dom = $(element).find('.submit .input-main');
 
         submit_dom.bind('click', function() {
+            var success = true;
             var data = {};
             var children = getChildren(element);
             for (var i = 0; i < children.length; i++) {
@@ -91,10 +92,15 @@ function MentoringBlock(runtime, element) {
 
         // init children (especially mrq blocks)
         var children = getChildren(element);
+        var options = {
+            blockValidator: validateXBlock
+        };
         _.each(children, function(child) {
-          callIfExists(child, 'init');
+          callIfExists(child, 'init', options);
         });
 
+        validateXBlock();
+
         if (submit_dom.length) {
             renderProgress();
         }
@@ -112,6 +118,31 @@ function MentoringBlock(runtime, element) {
         $.post(handlerUrl, '{}').success(handleRefreshResults);
     }
 
+    // validate all children
+    function validateXBlock() {
+        var submit_dom = $(element).find('.submit .input-main');
+        var children_are_valid = true;
+        var data = {};
+        var children = getChildren(element);
+
+        for (var i = 0; i < children.length; i++) {
+            var child = children[i];
+            if (child.name !== undefined) {
+                var child_validation = callIfExists(child, 'validate');
+                if (_.isBoolean(child_validation)) {
+                    children_are_valid = children_are_valid && child_validation
+                }
+            }
+        }
+
+        if (!children_are_valid) {
+            submit_dom.attr('disabled','disabled');
+        }
+        else {
+            submit_dom.removeAttr("disabled");
+        }
+    }
+
     // We need to manually refresh, XBlocks are currently loaded together with the section
     refreshXBlock(element);
 }

mentoring/templates/html/answer_editable.html

-<textarea class="answer editable" cols="50" rows="10" name="input">{{ self.student_input }}</textarea>
+<textarea
+   class="answer editable" cols="50" rows="10" name="input"
+   data-min_characters="{{ self.min_characters }}"
+   >{{ self.student_input }}</textarea>