Scheduling improvements (#3564)

* Handle case where initial API call fails

* Error if scheduling fails to retrieve

* Visual improvements for scheduling graph:

- Fixes for vertical scales
- Add "minimum stock level" line

* Refactor / improve query for list of BOM items a part can exist in

* Remove stock column from "substitute part" dialog

- Stock quantity no longer available in this serailizer

* Add a button to reload part scheduling information

* Add extra information to part scheduling API

- Include "speculative" quantity drawdown for build orders

* Add table of scheduling data

* Improved chart display

- Adds "minimum" and "maximum" expected values
- Adds table of scheduling information

* Bump API version

* Improve table rendering

* Improve axis scaling

* Add ability to dynamically refresh schedling data

* JS linting

* JS fix

InvenTree/InvenTree/api_version.py

@@ -2,11 +2,14 @@
 
 
 # InvenTree API version
-INVENTREE_API_VERSION = 70
+INVENTREE_API_VERSION = 71
 
 """
 Increment this API version number whenever there is a significant change to the API that any clients need to know about
 
+v71 -> 2022-08-18 : https://github.com/inventree/InvenTree/pull/3564
+    - Updates to the "part scheduling" API endpoint
+
 v70 -> 2022-08-02 : https://github.com/inventree/InvenTree/pull/3451
     - Adds a 'depth' parameter to the PartCategory list API
     - Adds a 'depth' parameter to the StockLocation list API

InvenTree/part/api.py

@@ -1,6 +1,6 @@
 """Provides a JSON API for the Part app."""
 
-import datetime
+import functools
 from decimal import Decimal, InvalidOperation
 
 from django.db import transaction
@@ -474,27 +474,27 @@ class PartScheduling(RetrieveAPI):
 
     def retrieve(self, request, *args, **kwargs):
         """Return scheduling information for the referenced Part instance"""
-        today = datetime.datetime.now().date()
 
         part = self.get_object()
 
         schedule = []
 
-        def add_schedule_entry(date, quantity, title, label, url):
+        def add_schedule_entry(date, quantity, title, label, url, speculative_quantity=0):
             """Check if a scheduled entry should be added:
 
             - date must be non-null
             - date cannot be in the "past"
             - quantity must not be zero
             """
-            if date and date >= today and quantity != 0:
-                schedule.append({
-                    'date': date,
-                    'quantity': quantity,
-                    'title': title,
-                    'label': label,
-                    'url': url,
-                })
+
+            schedule.append({
+                'date': date,
+                'quantity': quantity,
+                'speculative_quantity': speculative_quantity,
+                'title': title,
+                'label': label,
+                'url': url,
+            })
 
         # Add purchase order (incoming stock) information
         po_lines = order.models.PurchaseOrderLineItem.objects.filter(
@@ -571,23 +571,77 @@ class PartScheduling(RetrieveAPI):
         and just looking at what stock items the user has actually allocated against the Build.
         """
 
-        build_allocations = BuildItem.objects.filter(
-            stock_item__part=part,
-            build__status__in=BuildStatus.ACTIVE_CODES,
-        )
+        # Grab a list of BomItem objects that this part might be used in
+        bom_items = BomItem.objects.filter(part.get_used_in_bom_item_filter())
 
-        for allocation in build_allocations:
+        for bom_item in bom_items:
+            # Find a list of active builds for this BomItem
 
-            add_schedule_entry(
-                allocation.build.target_date,
-                -allocation.quantity,
-                _('Stock required for Build Order'),
-                str(allocation.build),
-                allocation.build.get_absolute_url(),
+            builds = Build.objects.filter(
+                status__in=BuildStatus.ACTIVE_CODES,
+                part=bom_item.part,
             )
 
+            for build in builds:
+
+                if bom_item.sub_part.trackable:
+                    # Trackable parts are allocated against the outputs
+                    required_quantity = build.remaining * bom_item.quantity
+                else:
+                    # Non-trackable parts are allocated against the build itself
+                    required_quantity = build.quantity * bom_item.quantity
+
+                # Grab all allocations against the spefied BomItem
+                allocations = BuildItem.objects.filter(
+                    bom_item=bom_item,
+                    build=build,
+                )
+
+                # Total allocated for *this* part
+                part_allocated_quantity = 0
+
+                # Total allocated for *any* part
+                total_allocated_quantity = 0
+
+                for allocation in allocations:
+                    total_allocated_quantity += allocation.quantity
+
+                    if allocation.stock_item.part == part:
+                        part_allocated_quantity += allocation.quantity
+
+                speculative_quantity = 0
+
+                # Consider the case where the build order is *not* fully allocated
+                if required_quantity > total_allocated_quantity:
+                    speculative_quantity = -1 * (required_quantity - total_allocated_quantity)
+
+                add_schedule_entry(
+                    build.target_date,
+                    -part_allocated_quantity,
+                    _('Stock required for Build Order'),
+                    str(build),
+                    build.get_absolute_url(),
+                    speculative_quantity=speculative_quantity
+                )
+
+        def compare(entry_1, entry_2):
+            """Comparison function for sorting entries by date.
+
+            Account for the fact that either date might be None
+            """
+
+            date_1 = entry_1['date']
+            date_2 = entry_2['date']
+
+            if date_1 is None:
+                return -1
+            elif date_2 is None:
+                return 1
+
+            return -1 if date_1 < date_2 else 1
+
         # Sort by incrementing date values
-        schedule = sorted(schedule, key=lambda entry: entry['date'])
+        schedule = sorted(schedule, key=functools.cmp_to_key(compare))
 
         return Response(schedule)
 
@@ -1746,28 +1800,7 @@ class BomList(ListCreateDestroyAPIView):
                 # Extract the part we are interested in
                 uses_part = Part.objects.get(pk=uses)
 
-                # Construct the database query in multiple parts
-
-                # A) Direct specification of sub_part
-                q_A = Q(sub_part=uses_part)
-
-                # B) BomItem is inherited and points to a "parent" of this part
-                parents = uses_part.get_ancestors(include_self=False)
-
-                q_B = Q(
-                    inherited=True,
-                    sub_part__in=parents
-                )
-
-                # C) Substitution of variant parts
-                # TODO
-
-                # D) Specification of individual substitutes
-                # TODO
-
-                q = q_A | q_B
-
-                queryset = queryset.filter(q)
+                queryset = queryset.filter(uses_part.get_used_in_bom_item_filter())
 
             except (ValueError, Part.DoesNotExist):
                 pass

InvenTree/part/models.py

@@ -1436,6 +1436,53 @@ class Part(MetadataMixin, MPTTModel):
 
         return parts
 
+    def get_used_in_bom_item_filter(self, include_inherited=True, include_variants=True, include_substitutes=True):
+        """Return a BomItem queryset which returns all BomItem instances which refer to *this* part.
+
+        As the BOM allocation logic is somewhat complicted, there are some considerations:
+
+        A) This part may be directly specified in a BomItem instance
+        B) This part may be a *variant* of a part which is directly specified in a BomItem instance
+        C) This part may be a *substitute* for a part which is directly specifed in a BomItem instance
+
+        So we construct a query for each case, and combine them...
+        """
+
+        # Cache all *parent* parts
+        parents = self.get_ancestors(include_self=False)
+
+        # Case A: This part is directly specified in a BomItem (we always use this case)
+        query = Q(
+            sub_part=self,
+            inherited=False,
+        )
+
+        if include_inherited:
+            query |= Q(
+                sub_part__in=parents,
+                inherited=True
+            )
+
+        if include_variants:
+            # Case B: This part is a *variant* of a part which is specified in a BomItem which allows variants
+            query |= Q(
+                allow_variants=True,
+                sub_part__in=parents,
+                inherited=False,
+            )
+
+        # Case C: This part is a *substitute* of a part which is directly specified in a BomItem
+        if include_substitutes:
+
+            # Grab a list of BomItem substitutes which reference this part
+            substitutes = self.substitute_items.all()
+
+            query |= Q(
+                pk__in=[substitute.bom_item.pk for substitute in substitutes],
+            )
+
+        return query
+
     def get_used_in_filter(self, include_inherited=True):
         """Return a query filter for all parts that this part is used in.
 

InvenTree/part/templates/part/detail.html

@@ -40,6 +40,11 @@
         <div class='d-flex flex-wrap'>
             <h4>{% trans "Part Scheduling" %}</h4>
             {% include "spacer.html" %}
+            <div class='btn-group' role='group'>
+                <button class='btn btn-primary' type='button' id='btn-schedule-reload' title='{% trans "Refresh scheduling data" %}'>
+                    <span class='fas fa-redo-alt'></span> {% trans "Refresh" %}
+                </button>
+            </div>
         </div>
     </div>
     <div class='panel-content'>
@@ -427,7 +432,12 @@
 
     // Load the "scheduling" tab
     onPanelLoad('scheduling', function() {
-        loadPartSchedulingChart('part-schedule-chart', {{ part.pk }});
+        var chart = loadPartSchedulingChart('part-schedule-chart', {{ part.pk }});
+
+        $('#btn-schedule-reload').click(function() {
+            chart.destroy();
+            loadPartSchedulingChart('part-schedule-chart', {{ part.pk }});
+        });
     });
 
     // Load the "suppliers" tab

InvenTree/part/templates/part/part_scheduling.html

@@ -4,3 +4,15 @@
 <div id='part-schedule' style='max-height: 300px;'>
     <canvas id='part-schedule-chart' width='100%' style='max-height: 300px;'></canvas>
 </div>
+
+<table class='table table-striped table-condensed' id='part-schedule-table'>
+    <thead>
+        <tr>
+            <th>{% trans "Link" %}</th>
+            <th>{% trans "Description" %}</th>
+            <th>{% trans "Date" %}</th>
+            <th>{% trans "Scheduled Quantity" %}</th>
+        </tr>
+    </thead>
+    <tbody></tbody>
+</table>

InvenTree/templates/js/translated/bom.js

@@ -519,7 +519,6 @@ function bomSubstitutesDialog(bom_item_id, substitutes, options={}) {
                 </a>
             </td>
             <td id='description-${pk}'><em>${part.description}</em></td>
-            <td id='stock-${pk}'><em>${part.stock}</em></td>
             <td>${buttons}</td>
         </tr>
         `;
@@ -552,7 +551,6 @@ function bomSubstitutesDialog(bom_item_id, substitutes, options={}) {
             <tr>
                 <th>{% trans "Part" %}</th>
                 <th>{% trans "Description" %}</th>
-                <th>{% trans "Stock" %}</th>
                 <th><!-- Actions --></th>
             </tr>
         </thead>

InvenTree/templates/js/translated/part.js

@@ -2257,6 +2257,14 @@ function initPriceBreakSet(table, options) {
 }
 
 
+/*
+ * Load a chart which displays projected scheduling information for a particular part.
+ * This takes into account:
+ * - Current stock levels / availability
+ * - Upcoming / scheduled build orders
+ * - Upcoming / scheduled sales orders
+ * - Upcoming / scheduled purchase orders
+ */
 function loadPartSchedulingChart(canvas_id, part_id) {
 
     var part_info = null;
@@ -2269,16 +2277,30 @@ function loadPartSchedulingChart(canvas_id, part_id) {
         }
     });
 
+    if (!part_info) {
+        console.error(`Error loading part information for part ${part_id}`);
+        return;
+    }
+
     var today = moment();
 
-    // Create an initial entry, using the available quantity
-    var stock_schedule = [
-        {
-            date: today,
-            delta: 0,
-            label: '{% trans "Current Stock" %}',
-        }
-    ];
+    /* Construct initial datasets for:
+     * - Scheduled quantity
+     * - Minimum speculative quantity
+     * - Maximum speculative quantity
+     */
+
+    var quantity_scheduled = [{
+        date: today,
+        delta: 0,
+    }];
+
+    // We will construct the HTML table as we go
+    var table_html = '';
+
+    // The "known" initial stock quantity
+    var initial_stock_min = part_info.in_stock;
+    var initial_stock_max = part_info.in_stock;
 
     /* Request scheduling information for the part.
      * Note that this information has already been 'curated' by the server,
@@ -2290,28 +2312,85 @@ function loadPartSchedulingChart(canvas_id, part_id) {
         {
             async: false,
             success: function(response) {
-                response.forEach(function(entry) {
-                    stock_schedule.push({
+
+                for (var idx = 0; idx < response.length; idx++) {
+
+                    var entry = response[idx];
+                    var date = entry.date != null ? moment(entry.date) : null;
+
+                    var date_string = entry.date;
+
+                    if (date == null) {
+                        date_string = '<em>{% trans "No date specified" %}</em>';
+                        date_string += `<span class='fas fa-exclamation-circle icon-red float-right' title='{% trans "No date specified" %}'></span>`;
+                    } else if (date < today) {
+                        date_string += `<span class='fas fa-exclamation-circle icon-yellow float-right' title='{% trans "Specified date is in the past" %}'></span>`;
+                    }
+
+                    var quantity_string = entry.quantity + entry.speculative_quantity;
+
+                    if (entry.speculative_quantity != 0) {
+                        quantity_string += `<span class='fas fa-info-circle icon-blue float-right' title='{% trans "Speculative" %}'></span>`;
+                    }
+
+                    // Add an entry to the scheduling table
+                    table_html += `
+                        <tr>
+                            <td><a href="${entry.url}">${entry.label}</a></td>
+                            <td>${entry.title}</td>
+                            <td>${date_string}</td>
+                            <td>${quantity_string}</td>
+                        </tr>
+                    `;
+
+                    // If the date is unknown or in the past, we cannot make use of this information
+                    // So we update the "speculative quantity"
+                    if (date == null || date < today) {
+                        if (entry.quantity < 0) initial_stock_min += entry.quantity;
+                        if (entry.speculative_quantity < 0) initial_stock_min += entry.speculative_quantity;
+
+                        if (entry.quantity > 0) initial_stock_max += entry.quantity;
+                        if (entry.speculative_quantity > 0) initial_stock_max += entry.speculative_quantity;
+
+                        // We do not add this entry to the graph
+                        continue;
+                    }
+
+                    // Add an entry to the scheduled quantity
+                    quantity_scheduled.push({
                         date: moment(entry.date),
                         delta: entry.quantity,
+                        speculative: entry.speculative_quantity,
                         title: entry.title,
                         label: entry.label,
                         url: entry.url,
                     });
-                });
+                }
+            },
+            error: function(response) {
+                console.error(`Error retrieving scheduling information for part ${part_id}`);
+                was_error = true;
             }
         }
     );
 
     // If no scheduling information is available for the part,
     // remove the chart and display a message instead
-    if (stock_schedule.length <= 1) {
+    if (quantity_scheduled.length <= 1) {
 
         var message = `
         <div class='alert alert-block alert-info'>
-            {% trans "No scheduling information available for this part" %}.<br>
+            {% trans "No scheduling information available for this part" %}.
         </div>`;
 
+        if (was_error) {
+            message = `
+                <div class='alert alert-block alert-danger'>
+                    {% trans "Error fetching scheduling information for this part" %}.
+                </div>
+            `;
+        }
+
         var canvas_element = $('#part-schedule-chart');
 
         canvas_element.closest('div').html(message);
@@ -2319,30 +2398,126 @@ function loadPartSchedulingChart(canvas_id, part_id) {
         return;
     }
 
-    // Iterate through future "events" to calculate expected quantity
+    var y_min = 0;
+    var y_max = 0;
 
+    // Iterate through future "events" to calculate expected quantity values
     var quantity = part_info.in_stock;
+    var speculative_min = initial_stock_min;
+    var speculative_max = initial_stock_max;
 
-    for (var idx = 0; idx < stock_schedule.length; idx++) {
+    // Datasets for speculative quantity
+    var q_spec_min = [];
+    var q_spec_max = [];
 
-        quantity += stock_schedule[idx].delta;
+    for (var idx = 0; idx < quantity_scheduled.length; idx++) {
 
-        stock_schedule[idx].x = stock_schedule[idx].date.format('YYYY-MM-DD');
-        stock_schedule[idx].y = quantity;
+        var speculative = quantity_scheduled[idx].speculative;
+        var date = quantity_scheduled[idx].date.format('YYYY-MM-DD');
+        var delta = quantity_scheduled[idx].delta;
+
+        // Update the running quantity
+        quantity += delta;
+
+        quantity_scheduled[idx].x = date;
+        quantity_scheduled[idx].y = quantity;
+
+        // Update minimum "speculative" quantity
+        speculative_min += delta;
+        speculative_max += delta;
+
+        if (speculative < 0) {
+            speculative_min += speculative;
+        } else if (speculative > 0) {
+            speculative_max += speculative;
+        }
+
+        q_spec_min.push({
+            x: date,
+            y: speculative_min,
+            label: 'label',
+            title: '',
+        });
+
+        q_spec_max.push({
+            x: date,
+            y: speculative_max,
+            label: 'label',
+            title: '',
+        });
+
+        // Update min / max values
+        if (quantity < y_min) y_min = quantity;
+        if (quantity > y_max) y_max = quantity;
     }
 
     var context = document.getElementById(canvas_id);
 
-    const data = {
-        datasets: [{
-            label: '{% trans "Scheduled Stock Quantities" %}',
-            data: stock_schedule,
-            backgroundColor: 'rgb(220, 160, 80)',
-            borderWidth: 2,
-            borderColor: 'rgb(90, 130, 150)'
-        }],
+    var data = {
+        datasets: [
+            {
+                label: '{% trans "Scheduled Stock Quantities" %}',
+                data: quantity_scheduled,
+                backgroundColor: 'rgba(160, 80, 220, 0.75)',
+                borderWidth: 3,
+                borderColor: 'rgb(160, 80, 220)'
+            },
+            {
+                label: '{% trans "Minimum Quantity" %}',
+                data: q_spec_min,
+                backgroundColor: 'rgba(220, 160, 80, 0.25)',
+                borderWidth: 2,
+                borderColor: 'rgba(220, 160, 80, 0.35)',
+                borderDash: [10, 5],
+                fill: '-1',
+            },
+            {
+                label: '{% trans "Maximum Quantity" %}',
+                data: q_spec_max,
+                backgroundColor: 'rgba(220, 160, 80, 0.25)',
+                borderWidth: 2,
+                borderColor: 'rgba(220, 160, 80, 0.35)',
+                borderDash: [10, 5],
+                fill: '-2',
+            },
+        ],
     };
 
+    if (part_info.minimum_stock) {
+        // Construct a 'minimum stock' threshold line
+        var minimum_stock_curve = [
+            {
+                x: today.format(),
+                y: part_info.minimum_stock,
+            },
+            {
+                x: quantity_scheduled[quantity_scheduled.length - 1].x,
+                y: part_info.minimum_stock,
+            }
+        ];
+
+        data.datasets.push({
+            data: minimum_stock_curve,
+            label: '{% trans "Minimum Stock Level" %}',
+            backgroundColor: 'rgba(250, 50, 50, 0.1)',
+            borderColor: 'rgba(250, 50, 50, 0.5)',
+            borderDash: [5, 5],
+            fill: {
+                target: {
+                    value: 0,
+                }
+            }
+        });
+    }
+
+    // Update the table
+    $('#part-schedule-table').find('tbody').html(table_html);
+
+    var y_range = y_max - y_min;
+
+    y_max += 0.1 * y_range;
+    y_min -= 0.1 * y_range;
+
     return new Chart(context, {
         type: 'scatter',
         data: data,
@@ -2359,7 +2534,8 @@ function loadPartSchedulingChart(canvas_id, part_id) {
                     },
                 },
                 y: {
-                    beginAtZero: true,
+                    min: y_min,
+                    max: y_max,
                 }
             },
             plugins: {