feature(qchat): share QML style when sending geojson vector in ws (#235)

Author: gounux

qtribu/gui/dck_qchat.py

@@ -1,7 +1,6 @@
 # standard
 import base64
 import json
-import os
 import tempfile
 from functools import partial
 from pathlib import Path
@@ -860,8 +859,8 @@ def on_send_screenshot_button_clicked(self) -> None:
         Action called when the Send QGIS screenshot button is clicked
         """
 
-        sc_fp = os.path.join(tempfile.gettempdir(), "qgis_screenshot.png")
-        self.iface.mapCanvas().saveAsImage(sc_fp)
+        sc_fp = Path(tempfile.gettempdir()) / "qgis_screenshot.png"
+        self.iface.mapCanvas().saveAsImage(str(sc_fp))
         with open(sc_fp, "rb") as file:
             data = file.read()
             message = QChatImageMessage(
@@ -1030,6 +1029,16 @@ def on_send_layer_to_qchat(self) -> None:
         exporter.setDestinationCrs(layer.crs())
         exporter.setTransformGeometries(True)
         geojson_str = exporter.exportFeatures(layer.getFeatures())
+
+        # save and read QML style to and from temp file
+        save_style_path = Path(tempfile.gettempdir()) / "qchat_layer_style.qml"
+        layer.saveNamedStyle(
+            str(save_style_path),
+            categories=QgsMapLayer.StyleCategory.AllStyleCategories,
+        )
+        with open(save_style_path, "r", encoding="utf-8") as file:
+            qml_style = file.read()
+
         message = QChatGeojsonMessage(
             type=QCHAT_MESSAGE_TYPE_GEOJSON,
             author=self.settings.author_nickname,
@@ -1038,5 +1047,6 @@ def on_send_layer_to_qchat(self) -> None:
             crs_wkt=layer.crs().toWkt(),
             crs_authid=layer.crs().authid(),
             geojson=json.loads(geojson_str),
+            style=qml_style,
         )
         self.qchat_ws.send_message(message)

qtribu/gui/qchat_tree_widget_items.py

@@ -1,13 +1,14 @@
 import base64
 import json
-import os
 import tempfile
+from pathlib import Path
 from typing import Optional
 
 from qgis.core import (
     QgsApplication,
     QgsCoordinateReferenceSystem,
     QgsCoordinateTransform,
+    QgsMapLayer,
     QgsPointXY,
     QgsProject,
     QgsRectangle,
@@ -223,14 +224,27 @@ def __init__(self, parent: QTreeWidget, message: QChatGeojsonMessage):
     def on_click(self, column: int) -> None:
         if column == MESSAGE_COLUMN:
             # save geojson to temp file
-            save_path = os.path.join(
-                tempfile.gettempdir(), f"{self.message.layer_name}.geojson"
+            save_path = (
+                Path(tempfile.gettempdir()) / f"{self.message.layer_name}.geojson"
             )
             with open(save_path, "w") as file:
                 json.dump(self.message.geojson, file)
+
+            # save QML style to temp file
+            save_style_path = (
+                Path(tempfile.gettempdir()) / f"{self.message.layer_name}_style.qml"
+            )
+            with open(save_style_path, "w", encoding="utf-8") as style_file:
+                style_file.write(self.message.style)
+
             # load geojson file into QGIS
-            layer = QgsVectorLayer(save_path, self.message.layer_name, "ogr")
+            layer = QgsVectorLayer(str(save_path), self.message.layer_name, "ogr")
             layer.setCrs(QgsCoordinateReferenceSystem.fromWkt(self.message.crs_wkt))
+            layer.loadNamedStyle(
+                str(save_style_path),
+                loadFromLocalDb=False,
+                categories=QgsMapLayer.StyleCategory.AllStyleCategories,
+            )
             QgsProject.instance().addMapLayer(layer)
 
     @property

qtribu/logic/qchat_messages.py

@@ -56,6 +56,7 @@ class QChatGeojsonMessage(QChatMessage):
     crs_wkt: str
     crs_authid: str
     geojson: dict
+    style: Optional[str]
 
 
 @dataclass(init=True, frozen=True)

qtribu/logic/qchat_websocket.py

@@ -34,6 +34,7 @@
     QChatUncompliantMessage,
 )
 from qtribu.toolbelt import PlgLogger
+from qtribu.toolbelt.exceptions import QChatMessageCanNotBeParsedException
 
 # conditional import depending on Qt version
 if int(QT_VERSION_STR.split(".")[0]) == 5:
@@ -133,23 +134,33 @@ def on_message_received(self, text: str) -> None:
             )
             return
         msg_type = message["type"]
-        if msg_type == QCHAT_MESSAGE_TYPE_UNCOMPLIANT:
-            self.uncompliant_message_received.emit(QChatUncompliantMessage(**message))
-        elif msg_type == QCHAT_MESSAGE_TYPE_TEXT:
-            self.text_message_received.emit(QChatTextMessage(**message))
-        elif msg_type == QCHAT_MESSAGE_TYPE_IMAGE:
-            self.image_message_received.emit(QChatImageMessage(**message))
-        elif msg_type == QCHAT_MESSAGE_TYPE_NB_USERS:
-            self.nb_users_message_received.emit(QChatNbUsersMessage(**message))
-        elif msg_type == QCHAT_MESSAGE_TYPE_NEWCOMER:
-            self.newcomer_message_received.emit(QChatNewcomerMessage(**message))
-        elif msg_type == QCHAT_MESSAGE_TYPE_EXITER:
-            self.exiter_message_received.emit(QChatExiterMessage(**message))
-        elif msg_type == QCHAT_MESSAGE_TYPE_LIKE:
-            self.like_message_received.emit(QChatLikeMessage(**message))
-        elif msg_type == QCHAT_MESSAGE_TYPE_GEOJSON:
-            self.geojson_message_received.emit(QChatGeojsonMessage(**message))
-        elif msg_type == QCHAT_MESSAGE_TYPE_CRS:
-            self.crs_message_received.emit(QChatCrsMessage(**message))
-        elif msg_type == QCHAT_MESSAGE_TYPE_BBOX:
-            self.bbox_message_received.emit(QChatBboxMessage(**message))
+        try:
+            if msg_type == QCHAT_MESSAGE_TYPE_UNCOMPLIANT:
+                self.uncompliant_message_received.emit(
+                    QChatUncompliantMessage(**message)
+                )
+            elif msg_type == QCHAT_MESSAGE_TYPE_TEXT:
+                self.text_message_received.emit(QChatTextMessage(**message))
+            elif msg_type == QCHAT_MESSAGE_TYPE_IMAGE:
+                self.image_message_received.emit(QChatImageMessage(**message))
+            elif msg_type == QCHAT_MESSAGE_TYPE_NB_USERS:
+                self.nb_users_message_received.emit(QChatNbUsersMessage(**message))
+            elif msg_type == QCHAT_MESSAGE_TYPE_NEWCOMER:
+                self.newcomer_message_received.emit(QChatNewcomerMessage(**message))
+            elif msg_type == QCHAT_MESSAGE_TYPE_EXITER:
+                self.exiter_message_received.emit(QChatExiterMessage(**message))
+            elif msg_type == QCHAT_MESSAGE_TYPE_LIKE:
+                self.like_message_received.emit(QChatLikeMessage(**message))
+            elif msg_type == QCHAT_MESSAGE_TYPE_GEOJSON:
+                self.geojson_message_received.emit(QChatGeojsonMessage(**message))
+            elif msg_type == QCHAT_MESSAGE_TYPE_CRS:
+                self.crs_message_received.emit(QChatCrsMessage(**message))
+            elif msg_type == QCHAT_MESSAGE_TYPE_BBOX:
+                self.bbox_message_received.emit(QChatBboxMessage(**message))
+        except KeyError:
+            text = self.tr(
+                "Unintelligible message received. Please make sure you are using the latest plugin version. (type={type})"
+            ).format(type=msg_type)
+            message = QChatUncompliantMessage(reason=text)
+            self.uncompliant_message_received.emit(message)
+            raise QChatMessageCanNotBeParsedException(message=text)

qtribu/toolbelt/exceptions.py

@@ -0,0 +1,2 @@
+class QChatMessageCanNotBeParsedException(Exception):
+    pass