Merge pull request #13 from EftyK/main

Update README, add test for Import tab, and fix few bugs

Author: nicevibesplus

README.md

@@ -55,6 +55,7 @@ QFlowCrate will help you document the **metadata** of your project, prompting to
 | **Custom metadata entry** | UI helps the user fill in title, description, and author details. |
 | **Cross‑platform** | Works on Windows, macOS, and Linux Ubuntu (QGIS ≥ 3.40). |
 | **Data‑format support** | <br>• **Vector:** Shapefile (`.shp`), GeoJSON (`.geojson`), KML (`.kml`) <br>• **Raster:** GeoTIFF (`.tif/.tiff`), PNG (`.png`), JPEG (`.jpg`) <br>• **Other:** CSV tables, OGC-compliant server connections (WFS, WMS) |
+| **RO‑Crate import** | Imports a RO-Crate ZIP for visualization and inspection. Workflow re-execution is currently not supported. |
 
 ---
 
@@ -134,6 +135,12 @@ ProjectA/
    └─ symbology.qml
 ```
 
+### Step 7 – Import a RO‑Crate  
+
+1. Navigate to the Import tab.
+1. Browse an already exported RO-Crate zip file.
+1. Visualize the graph and inspect the graph elements for details. 
+
 ---
 
 

images/showcase.gif

@@ -20,18 +20,21 @@ class ConnectionArrow(QGraphicsLineItem):
     # INITIALIZATION
     # ============================================================================
 
-    def __init__(self, start_node, end_node):
+    def __init__(self, start_node, end_node, deletable=True):
         """Initialize a ConnectionArrow between two nodes.
 
         :param start_node: Starting node for the connection
         :type start_node: LayerNode or ProcessNode
         :param end_node: Ending node for the connection
         :type end_node: LayerNode or ProcessNode
+        :param deletable: Whether the arrow can be deleted by clicking
+        :type deletable: bool
         """
         super().__init__()
         self.start_node = start_node
         self.end_node = end_node
         self.arrowhead = None  # Will hold the arrowhead polygon
+        self.deletable = deletable
 
         # Set visual properties
         self.setPen(QPen(Qt.black, 2))
@@ -57,7 +60,7 @@ def __init__(self, start_node, end_node):
             if self.arrowhead:
                 scene.addItem(self.arrowhead)
 
-        self.setToolTip("Click to delete connection")
+        self.setToolTip("Double click to delete connection" if self.deletable else "")
 
     # ============================================================================
     # POSITION CALCULATION
@@ -204,12 +207,12 @@ def _create_arrowhead(self, tip_point, dx, dy):
     # ============================================================================
 
     def mousePressEvent(self, event):  # noqa: N802
-        """Delete arrow on click.
+        """Delete arrow on click if deletable.
 
         :param event: Mouse press event
         :type event: QMouseEvent
         """
-        if event.button() == Qt.LeftButton:
+        if event.button() == Qt.LeftButton and self.deletable:
             self.remove_arrow()
 
     # ============================================================================

qflowcrate/Plugin/Graph/connection_arrow.py

@@ -34,6 +34,9 @@ def __init__(self):
         self.setAcceptDrops(True)
         self.setDragMode(QGraphicsView.RubberBandDrag)
 
+        # Enable keyboard focus for zoom shortcuts
+        self.setFocusPolicy(Qt.StrongFocus)
+
         # Connection mode
         self.connection_mode = False
         self.connection_start = None
@@ -93,6 +96,32 @@ def dropEvent(self, event):  # noqa: N802
     # MOUSE EVENT HANDLERS
     # ============================================================================
 
+    def keyPressEvent(self, event):  # noqa: N802
+        """Handle keyboard shortcuts for zooming.
+
+        :param event: Key press event
+        :type event: QKeyEvent
+        """
+        if event.modifiers() & Qt.ControlModifier:
+            if event.key() == Qt.Key_Plus:
+                # Zoom in
+                zoom_factor = 1.2
+                current_scale = self.transform().m11()
+                new_scale = current_scale * zoom_factor
+                if new_scale <= 5.0:
+                    self.scale(zoom_factor, zoom_factor)
+            elif event.key() == Qt.Key_Minus:
+                # Zoom out
+                zoom_factor = 1.0 / 1.2
+                current_scale = self.transform().m11()
+                new_scale = current_scale * zoom_factor
+                if new_scale >= 0.1:
+                    self.scale(zoom_factor, zoom_factor)
+            else:
+                super().keyPressEvent(event)
+        else:
+            super().keyPressEvent(event)
+
     def mousePressEvent(self, event):  # noqa: N802
         """Handle mouse press for connections.
 
@@ -193,7 +222,11 @@ def toggle_connection_mode(self, enabled):
         """
         self.connection_mode = enabled
         if not enabled and self.connection_start:
-            self.connection_start.setBrush(
-                self._get_original_brush(self.connection_start)
-            )
+            try:
+                self.connection_start.setBrush(
+                    self._get_original_brush(self.connection_start)
+                )
+            except RuntimeError:
+                # Object has been deleted
+                pass
             self.connection_start = None

qflowcrate/Plugin/Graph/graph_view.py

@@ -36,12 +36,12 @@
 class ImportedLayer:
     """Mock layer object rich enough to satisfy LayerMetadataDialog"""
     def __init__(self, dataset_entity, entity_map):
-        self.id = dataset_entity["@id"]
-        self.name = dataset_entity["name"]
+        self.id = dataset_entity.get("@id", "unknown")
+        self.name = dataset_entity.get("name", "Unknown Layer")
         self.clean_name = self.name
-        self.description = dataset_entity["description"]
+        self.description = dataset_entity.get("description", "")
 
-        visible_val = dataset_entity["layerVisible"]
+        visible_val = dataset_entity.get("layerVisible", True)
         self.visible = str(visible_val).lower() == "true" if isinstance(visible_val, str) else bool(visible_val)
 
         # Prepare default values
@@ -55,19 +55,19 @@ def __init__(self, dataset_entity, entity_map):
 
         # Find geometry entity which contains technical & external metadata
         geometry_entity = None
-        has_parts = dataset_entity["hasPart"]
+        has_parts = dataset_entity.get("hasPart", [])
         if isinstance(has_parts, dict): 
             has_parts = [has_parts]
 
         for part_ref in has_parts:
-            part_id = part_ref if isinstance(part_ref, str) else part_ref["@id"]
+            part_id = part_ref if isinstance(part_ref, str) else part_ref.get("@id", "")
             if part_id in entity_map and "geometry" in part_id.lower():
                 geometry_entity = entity_map[part_id]
                 break
 
         # Extract metadata from geometry entity
         if geometry_entity:
-            self.source = geometry_entity["@id"]
+            self.source = geometry_entity.get("@id", self.id)
 
             # Extract layer type (fall back to additionalType if layerType is somehow missing)
             raw_type = geometry_entity.get("layerType", geometry_entity.get("additionalType", "Unknown"))
@@ -96,11 +96,11 @@ class ImportedProcess:
     """Mock process object rich enough to satisfy ProcessMetadataDialog"""
     def __init__(self, action_entity, instrument_entity=None):
         self.id = action_entity["@id"]
-        self.name = action_entity["name"]
-        self.description = action_entity["description"]
+        self.name = action_entity.get("name", "Unknown Process")
+        self.description = action_entity.get("description", "")
 
         if instrument_entity:
-            self.algorithm_id = instrument_entity["name"]
+            self.algorithm_id = instrument_entity.get("name", "Unknown Algorithm")
         else:
             self.algorithm_id = "Unknown Algorithm"
 
@@ -115,9 +115,9 @@ def __init__(self, action_entity, instrument_entity=None):
                 self.timestamp = "Unknown Time"
 
         # Read custom QGIS properties
-        self.log = action_entity["qgisLog"]
-        raw_params = action_entity["qgisParameters"]
-        raw_results = action_entity["qgisResults"]
+        self.log = action_entity.get("qgisLog", "")
+        raw_params = action_entity.get("qgisParameters", "{}")
+        raw_results = action_entity.get("qgisResults", "{}")
 
         # Convert JSON strings to dictionaries for UI rendering in the metadata dialog
         try:
@@ -158,7 +158,8 @@ def setup_ui(self):
 
         instruction_label = QLabel(
             "Select an exported RO-Crate (.zip) file to visualize its workflow graph. "
-            "This view is read-only. Right-click any node to inspect its metadata."
+            "This view is read-only. Right-click any node to inspect its metadata. "
+            "To zoom in and out of the graph, use the keyboard shortcuts Ctrl & '+' / Ctrl & '-', respectively."
         )
         instruction_label.setWordWrap(True)
         main_layout.addWidget(instruction_label)
@@ -257,11 +258,11 @@ def load_graph_from_crate(self, zip_path):
                 action_id = action["@id"]
 
                 # Fetch instrument entity to pass to our Mock Process
-                instrument_refs = action["instrument"]
+                instrument_refs = action.get("instrument", [])
                 instrument_entity = None
                 if instrument_refs:
                     ref_id = instrument_refs[0]["@id"] if isinstance(instrument_refs, list) else instrument_refs["@id"]
-                    instrument_entity = self.entity_map[ref_id]
+                    instrument_entity = self.entity_map.get(ref_id)
 
                 # Create Process Node
                 process_obj = ImportedProcess(action, instrument_entity)
@@ -271,23 +272,23 @@ def load_graph_from_crate(self, zip_path):
                 self.graph_view.scene.addItem(p_node)
 
                 # Process Inputs (Data -> Process)
-                inputs = action["object"]
+                inputs = action.get("object", [])
                 if isinstance(inputs, dict): 
                     inputs = [inputs]
 
                 for input_ref in inputs:
-                    in_id = input_ref["@id"]
+                    in_id = input_ref.get("@id")
                     if in_id:
                         norm_in_id = self._ensure_layer_node_exists(in_id)
                         connections_to_make.append((norm_in_id, action_id))
 
                 # Process Outputs (Process -> Data)
-                outputs = action["result"]
+                outputs = action.get("result", [])
                 if isinstance(outputs, dict): 
                     outputs = [outputs]
 
                 for output_ref in outputs:
-                    out_id = output_ref["@id"]
+                    out_id = output_ref.get("@id")
                     if out_id:
                         norm_out_id = self._ensure_layer_node_exists(out_id)
                         connections_to_make.append((action_id, norm_out_id))
@@ -298,7 +299,7 @@ def load_graph_from_crate(self, zip_path):
                 target_node = self.nodes_map.get(target_id)
 
                 if source_node and target_node:
-                    arrow = ConnectionArrow(source_node, target_node)
+                    arrow = ConnectionArrow(source_node, target_node, deletable=False)
                     self.graph_view.scene.addItem(arrow)
 
             # 6. Apply auto-layout
@@ -407,4 +408,11 @@ def _apply_auto_layout(self, edges):
                     arrow.update_position()
             elif isinstance(node, ProcessNode):
                 for arrow in node.input_arrows + node.output_arrows:
-                    arrow.update_position()
+                    arrow.update_position()
+
+        # Update scene rect to encompass all items
+        scene_rect = self.graph_view.scene.itemsBoundingRect()
+        self.graph_view.scene.setSceneRect(scene_rect)
+
+        # Fit the view to show all items within the visible area
+        self.graph_view.fitInView(scene_rect, Qt.KeepAspectRatio)

qflowcrate/Plugin/Import/import_tab.py

@@ -45,8 +45,14 @@ def setup_ui(self):
         scroll_area.setWidgetResizable(True)
         scroll_area.setFrameStyle(QFrame.NoFrame)
 
+        # Create container widget for scroll area content
+        container = QWidget()
+        container_layout = QVBoxLayout(container)
+        container_layout.setContentsMargins(10, 10, 10, 10)
+        container_layout.setSpacing(12)
+
         self._add_section(
-            main_layout,
+            container_layout,
             "Application Overview",
             "This plugin helps you to document your project and its creation workflow. "
             "It exports to RO-Crate 1.1 to enable sharing of the map. The export "
@@ -56,7 +62,7 @@ def setup_ui(self):
 
         # Graph tab instructions
         self._add_section(
-            main_layout,
+            container_layout,
             "Graph Tab - Creating Your Workflow",
             "This tab allows you to create your projects workflow. All the nodes in "
             "this graph will be exported to the RO-Crate.",
@@ -74,10 +80,12 @@ def setup_ui(self):
             "ask for a title and description.",
             "Step 3: Add connections between the graphs layers and processing steps. "
             "This creates a complete workflow diagram. Without this, the dependencies "
-            "of the layers will be missing in the final export.",
+            "of the layers will be missing in the final export. "
+            "The user can zoom in and out of the graph using the keyboard shortcuts "
+            "Ctrl & '+' / Ctrl & '-', respectively.",
         )
         self._add_section(
-            main_layout,
+            container_layout,
             "Export Tab - Exporting Your Workflow",
             "This tab allows you to export your projects workflow to RO-Crate.",
             "Step 1: Enter author information. This must include the authors name. "
@@ -90,12 +98,13 @@ def setup_ui(self):
             "hit Export RO-Crate.",
         )
         self._add_section(
-            main_layout,
+            container_layout,
             "Import Tab - Importing an Existing RO-Crate",
             "This tab allows you to import an existing RO-Crate. This can be used to "
             "recreate the workflow graph from a previously exported RO-Crate.",
         )
 
+        scroll_area.setWidget(container)
         main_layout.addWidget(scroll_area)
         self.setLayout(main_layout)