Fix #1 - pretrained model selection bug

1) Removed the select field for previous networks snapshots from forms.py, due to wtforms validation issues. Then included code in views.py and new.html, to display the select fields for previous networks snapshots in html and for validating these fields. These changes fix the pretrained model selection bug. Also these changes ensure the display of error message, incase user selects the job that doesn't exists (this scenario happens when a user selects the job and at the same if another user deletes this job)
2) fix to the following issue: when validation fails, the selected radio buttons in "previous networks" tab remains selected but the select input field and customize button beside the selected previous network is in hidden status, which is wrong. same issue exists in standard networks tab. Modified new.html to ensure that select field and customize button beside selected radio button will be visible even when validation fails.
3) Modified the test case related to pretrained model selection.
4) Included the changes to display the selected "pretrained model" details in show.html file

digits/model/forms.py

@@ -16,6 +16,13 @@ def __init__(self, csrf_enabled=False, *args, **kwargs):
         super(ModelForm, self).__init__(csrf_enabled=csrf_enabled, *args, **kwargs)
 
     ### Methods
+    def selection_exists_in_choices(form, field):
+        found=False
+        for i, choice in enumerate(field.choices):
+            if choice[0] == field.data:
+                found=True
+        if found == False:
+            raise validators.ValidationError("Selected job doesn't exist. Maybe it was deleted by another user.")
 
     def required_if_method(value):
         def _required(form, field):
@@ -144,15 +151,10 @@ def validate_lr_multistep_values(form, field):
             choices = [],
             validators = [
                 required_if_method('previous'),
+                selection_exists_in_choices,
                 ],
             )
 
-    previous_network_snapshots = wtforms.FieldList(
-            wtforms.SelectField('Snapshots',
-                validators = [validators.Optional()]
-                ),
-            )
-
     custom_network = wtforms.TextAreaField('Custom Network',
             validators = [
                 required_if_method('custom'),
@@ -175,3 +177,5 @@ def validate_custom_network_snapshot(form, field):
                 ]
             )
 
+
+

digits/model/images/classification/test_views.py

@@ -1,6 +1,8 @@
 # Copyright (c) 2014-2015, NVIDIA CORPORATION.  All rights reserved.
 
 import re
+import os
+import tempfile
 
 import unittest
 import mock
@@ -52,11 +54,20 @@ def setupClass(cls):
         mj = mock.Mock(spec=digits.model.ImageClassificationModelJob)
         mj.id.return_value = 'model'
         mj.name.return_value = ''
-        mj.train_task.return_value.snapshots = [('path', 1)]
+        _, cls.temp_snapshot_path = tempfile.mkstemp() #instead of using a dummy hardcoded value as snapshot path, temp file path is used to avoid the filen't exists exception in views.py.
+        mj.train_task.return_value.snapshots = [(cls.temp_snapshot_path, 1)]
         mj.train_task.return_value.network = caffe_pb2.NetParameter()
 
         digits.webapp.scheduler.jobs = [dj, mj]
 
+    @classmethod
+    def tearDownClass(cls):
+        super(TestCreate, cls).tearDownClass()
+        try:
+            os.remove(cls.temp_snapshot_path)
+        except OSError:
+            pass
+
     def test_empty_request(self):
         """empty request"""
         rv = self.app.post(self.url)
@@ -76,7 +87,6 @@ def test_crop_size(self):
 
         assert scheduler.jobs[-1].train_task().crop_size == 12
 
-    @unittest.skip('expected failure')
     def test_previous_network_pretrained_model(self):
         """previous network, pretrained model"""
 
@@ -85,9 +95,7 @@ def test_previous_network_pretrained_model(self):
             'model_name': 'test',
             'dataset': 'dataset',
             'previous_networks': 'model',
-            # TODO: select snapshot 1
+            'model-snapshot' : 1
             })
 
-        assert scheduler.jobs[-1].train_task().pretrained_model == 'path'
-        assert False
-
+        assert scheduler.jobs[-1].train_task().pretrained_model == self.temp_snapshot_path

digits/model/images/classification/views.py

@@ -31,9 +31,10 @@ def image_classification_model_new():
     form.standard_networks.choices = get_standard_networks()
     form.standard_networks.default = get_default_standard_network()
     form.previous_networks.choices = get_previous_networks()
-    set_previous_network_snapshots(form)
 
-    return render_template('models/images/classification/new.html', form=form, has_datasets=(len(get_datasets())==0))
+    prev_network_snapshots = get_previous_network_snapshots()
+
+    return render_template('models/images/classification/new.html', form=form, previous_network_snapshots=prev_network_snapshots, has_datasets=(len(get_datasets())==0))
 
 @app.route(NAMESPACE, methods=['POST'])
 def image_classification_model_create():
@@ -42,10 +43,11 @@ def image_classification_model_create():
     form.standard_networks.choices = get_standard_networks()
     form.standard_networks.default = get_default_standard_network()
     form.previous_networks.choices = get_previous_networks()
-    set_previous_network_snapshots(form)
+
+    prev_network_snapshots = get_previous_network_snapshots()
 
     if not form.validate_on_submit():
-        return render_template('models/images/classification/new.html', form=form), 400
+        return render_template('models/images/classification/new.html', form=form, previous_network_snapshots=prev_network_snapshots), 400
 
     datasetJob = scheduler.get_job(form.dataset.data)
     if not datasetJob:
@@ -81,13 +83,19 @@ def image_classification_model_create():
             network.CopyFrom(old_job.train_task().network)
             for i, choice in enumerate(form.previous_networks.choices):
                 if choice[0] == form.previous_networks.data:
-                    epoch = form.previous_network_snapshots[i].data
-                    if epoch != 'none':
+                    epoch = int(request.form['%s-snapshot' % form.previous_networks.data])
+                    if epoch != 0:
                         for filename, e in old_job.train_task().snapshots:
                             if e == epoch:
                                 pretrained_model = filename
                                 break
+
+                        if pretrained_model is None:
+                            raise Exception("For the job %s, selected pretrained_model for epoch %d is invalid!" % (form.previous_networks.data, epoch))
+                        if not (os.path.exists(pretrained_model)):
+                            raise Exception("Pretrained_model for the selected epoch doesn't exists. May be deleted by another user/process. Please restart the server to load the correct pretrained_model details")
                     break
+
         elif form.method.data == 'custom':
             text_format.Merge(form.custom_network.data, network)
             pretrained_model = form.custom_network_snapshot.data.strip()
@@ -282,13 +290,11 @@ def get_previous_networks():
         )
         ]
 
-def set_previous_network_snapshots(form):
-    while len(form.previous_network_snapshots):
-        form.previous_network_snapshots.pop_entry()
-
+def get_previous_network_snapshots():
+    prev_network_snapshots = []
     for job_id, _ in get_previous_networks():
         job = scheduler.get_job(job_id)
-        e = form.previous_network_snapshots.append_entry()
-        e.choices = [('none', 'None')] + [(epoch, 'Epoch #%s' % epoch)
+        e = [(0, 'None')] + [(epoch, 'Epoch #%s' % epoch)
                 for _, epoch in reversed(job.train_task().snapshots)]
-
+        prev_network_snapshots.append(e)
+    return prev_network_snapshots

digits/templates/models/images/classification/new.html

@@ -421,12 +421,16 @@ <h4>Solver Options</h4>
                                 <a href="{{url_for("models_show", job_id=network.data)}}" target="_blank">View</a>
                             </td>
                             <td>
-                                {% set snapshot_list = form.previous_network_snapshots[loop.index0] %}
-                                {% if snapshot_list.choices|length %}
-                                {{snapshot_list(class='form-control')}}
+                                {% set snapshot_list = previous_network_snapshots[loop.index0] %}
+                                {% if snapshot_list|length %}
+                                <select class="form-control" id="{{network.data}}-snapshot" name="{{network.data}}-snapshot">
+                                    {% for each_epoch in snapshot_list %}
+                                    <option value="{{each_epoch[0]}}">{{each_epoch[1]}}</option>
+                                    {% endfor %}
+                                </select>
                                 {% endif %}
                             </td>
-                            <td><a class="btn btn-sm" onClick="customizeNetwork('{{network.data}}', '{{snapshot_list.id}}');">Customize</a></td>
+                            <td><a class="btn btn-sm" onClick="customizeNetwork('{{network.data}}', '{{network.data}}-snapshot');">Customize</a></td>
                         </tr>
                         {% else %}
                         <tr>
@@ -436,26 +440,41 @@ <h4>Solver Options</h4>
                     </table>
                 </div>
 		<script>
-                    $(".btn.btn-sm").hide();   // hide all the buttons
-                    $("#network-tab-previous").find(".form-control").prop('disabled', 'disabled');  //hide all the select elements in "Previous Networks" tab
+                    $(".btn.btn-sm").css('visibility', 'hidden');   // hide all the buttons
+                    $("#network-tab-previous").find(".form-control").css('visibility', 'hidden'); //hide all the select elements in "Previous Networks" tab
+
                     var $stdtab_prev_clicked_tr = null;   
                     $("input:radio[name=standard_networks]").click(function(){
                        if ($stdtab_prev_clicked_tr != null) {
-                            $stdtab_prev_clicked_tr.find(".btn.btn-sm").hide();
-                        }
-                        $(this).parents('tr').find(".btn.btn-sm").show();
-                        $stdtab_prev_clicked_tr = $(this).parents('tr');
+                            $stdtab_prev_clicked_tr.find(".btn.btn-sm").css('visibility', 'hidden');
+                       }
+                       $(this).parents('tr').find(".btn.btn-sm").css('visibility', 'visible');
+                       $stdtab_prev_clicked_tr = $(this).parents('tr');
                     });
+
                     var $prevtab_prev_clicked_tr = null;   
                     $("input:radio[name=previous_networks]").click(function(){
                        if ($prevtab_prev_clicked_tr != null) {
-                            $prevtab_prev_clicked_tr.find(".btn.btn-sm").hide();
-                            $prevtab_prev_clicked_tr.find(".form-control").prop('disabled', 'disabled');
+                            $prevtab_prev_clicked_tr.find(".btn.btn-sm").css('visibility', 'hidden');
+                            $prevtab_prev_clicked_tr.find(".form-control").css('visibility', 'hidden');
                         }
-                        $(this).parents('tr').find(".btn.btn-sm").show();
-                        $(this).parents('tr').find(".form-control").prop('disabled', false);
+                        $(this).parents('tr').find(".btn.btn-sm").css('visibility', 'visible');
+                        $(this).parents('tr').find(".form-control").css('visibility', 'visible');
                         $prevtab_prev_clicked_tr = $(this).parents('tr');
                     });
+
+                    //fix to the following issue: when validation fails and the screen was re-displayed, the selected radio buttons in "previous networks" tab remains selected but the select input field and customize button beside the selected previous network is in hidden status, which is wrong. same issue exists in standard networks tab. The below code ensures that select field and customize button beside selected radio button will be visible even when validation fails.
+
+                    if($("input:radio[name=standard_networks]").is(":checked")) {
+                       $stdtab_prev_clicked_tr = $("input:radio[name=standard_networks]:checked").parents('tr');
+                       $stdtab_prev_clicked_tr.find(".btn.btn-sm").css('visibility', 'visible');
+                    }
+                    if($("input:radio[name=previous_networks]").is(":checked")) {
+                        $prevtab_prev_clicked_tr =  $("input:radio[name=previous_networks]:checked").parents('tr');
+                        $prevtab_prev_clicked_tr.find(".btn.btn-sm").css('visibility', 'visible');
+                        $prevtab_prev_clicked_tr.find(".form-control").css('visibility', 'visible');
+                    }
+
                 </script>
                 <div id="network-tab-custom" class="tab-pane">
                     <script>

digits/templates/models/images/classification/show.html

@@ -18,6 +18,10 @@
                 <dd><a href="{{url_for('serve_file', path=task.path(task.deploy_file, relative=True))}}">{{task.deploy_file}}</a></dd>
                 <dt>Raw caffe output</dt>
                 <dd><a href="{{url_for('serve_file', path=task.path(task.caffe_log_file, relative=True))}}">{{task.caffe_log_file}}</a></dd>
+                {% if task.pretrained_model %}
+                <dt>Pretrained Model</dt>
+                <dd>{{task.pretrained_model}}</dd>
+                {% endif %}
             </dl>
         </div>
     </div>