Toggling pregrading and Identifying blank solutions

This merge request does two things:

• Automatically identify blank solutions (either multiple choice or not) and set a feedback option named 'blank' for each one.
• When creating an exam, there are three options to specify which questions should be graded automatically.
• Pre-grade a question again if a submission is reuploaded and is automatically graded (by 'Zesje')

The grading policy is specified in the following way:

• 0/set_nothing: Manually approve everything
• 1/set_blank: Automatically approve blank solutions
• 2/set_blank_single: Automatically approve blank solutions or solutions with one answer

Add a new field to a problem in the database with this number.

For a more detailed description, see #61.

Closes #33 and #61.

client/views/Exam.jsx

@@ -47,6 +47,7 @@ class Exams extends React.Component {
             page: problem.page,
             name: problem.name,
             graded: problem.graded,
+            grading_policy: problem.grading_policy,
             feedback: problem.feedback || [],
             mc_options: problem.mc_options.map((option) => {
               // the database stores the positions of the checkboxes but the front end uses the top-left position
@@ -195,13 +196,40 @@ class Exams extends React.Component {
     const problem = changedWidget.problem
     if (!problem) return
 
-    api.put('problems/' + problem.id + '/name', { name: problem.name })
+    api.put('problems/' + problem.id, { name: problem.name })
       .catch(e => Notification.error('Could not save new problem name: ' + e))
       .then(this.setState({
         changedWidgetId: null
       }))
   }
 
+  onChangeAutoApproveType (e) {
+    const selectedWidgetId = this.state.selectedWidgetId
+    if (!selectedWidgetId) return
+
+    const selectedWidget = this.state.widgets[selectedWidgetId]
+    if (!selectedWidget) return
+
+    const problem = selectedWidget.problem
+    if (!problem) return
+
+    const newPolicy = e.target.value
+
+    api.put('problems/' + problem.id, { grading_policy: newPolicy })
+      .catch(e => Notification.error('Could not change grading policy: ' + e))
+      .then(this.setState(prevState => ({
+        widgets: update(prevState.widgets, {
+          [selectedWidgetId]: {
+            problem: {
+              grading_policy: {
+                $set: newPolicy
+              }
+            }
+          }
+        })
+      })))
+  }
+
   createNewWidget = (widgetData) => {
     this.setState((prevState) => {
       return {
@@ -738,6 +766,20 @@ class Exams extends React.Component {
             }
           </React.Fragment>
         )}
+        {props.problem &&
+          <React.Fragment>
+            <div className='panel-block mcq-block'>
+              <b>Auto-approve</b>
+              <div className='select is-hovered is-fullwidth'>
+                <select value={props.problem.grading_policy} onChange={this.onChangeAutoApproveType.bind(this)}>
+                  <option value='0'>Nothing</option>
+                  <option value='1'>Blanks</option>
+                  {props.problem.mc_options.length !== 0 && <option value='2'>One answer/blanks</option>}
+                </select>
+              </div>
+            </div>
+          </React.Fragment>
+        }
         <div className='panel-block'>
           <button
             disabled={props.disabledDelete}

[jtimotei]

If you first do catch and then then what you get is that the then callback is also executed if the api call results in an error. If you switch the order and an error occurs in api.put, the then callback does not get executed but the catch does. See for yourself if you want to update the state in case of an error.

[Ghost User]

I think @hleistra changed this?