Startup - expressions (#132)

* Startup - expressions

* Fixing

* updating

* Polishing

* Update metadata.txt

metadata.txt

@@ -6,7 +6,7 @@ author=Akbar Gumbira, Håvard Tveite
 qgisMinimumVersion=3.0
 description=Download shared collections
 about=Search for published collections and install them for use with QGIS. Symbology (SVG, images, styles), Processing scripts, Processing models and R scripts are supported. There are several options for repositories: Github, Bitbucket, local file system and HTTP(S).
-version=0.14.1
+version=0.15.0
 tracker=https://github.com/QGIS-Contribution/QGIS-ResourceSharing/issues
 repository=https://github.com/QGIS-Contribution/QGIS-ResourceSharing.git
 
@@ -17,6 +17,7 @@ experimental=False
 deprecated=False
 icon=resources/icon.png
 changelog=
+        0.15.0 - Support expressions (#130). Switch to Python pathlib.
         0.14.1 - Also support QGIS 3.4 (avoid install of style labelsettings and textformatting for v. < 3.10 - #127)
                - Try another way to avoid [WinError 5] on Microsoft Windows (#103)
         0.14.0 - Style import improvements (fix colorramp support, add support for label settings and text formats, clean up Style Manager tags) (#113, #114, #116, #118)

resource_sharing/collection_manager.py

@@ -120,6 +120,13 @@ def get_html(self, collection_id):
            if config.COLLECTIONS[collection_id]['models'] > 1:
                html = html + 's'
            resource_types = resource_types + 1
+        if 'expressions' in config.COLLECTIONS[collection_id].keys():
+           if resource_types > 0:
+               html = html + ', '
+           html = html + str(config.COLLECTIONS[collection_id]['expressions']) + ' Expression (JSON) file'
+           if config.COLLECTIONS[collection_id]['expressions'] > 1:
+               html = html + 's'
+           resource_types = resource_types + 1
         if 'processing' in config.COLLECTIONS[collection_id].keys():
            if resource_types > 0:
                html = html + ', '

resource_sharing/config.py

@@ -25,6 +25,7 @@
             'preview': ['preview/image1.png', 'preview/image2.png']
             # Additional entries (for resource statistics):
             'models': count of models in the collection,
+            'expressions': count of expression files in the collection,
             'processing': count of processing scripts in the collection,
             'rscripts': count of R scripts in the collection,
             'style': count of layer styles (QML) in the collection,

resource_sharing/gui/resource_sharing_dialog.py

@@ -505,6 +505,11 @@ def install_finished(self):
                 message = message + '\n<li> ' + str(number) + ' model'
                 if number > 1:
                     message = message + 's'
+            if 'expressions' in config.COLLECTIONS[self._selected_collection_id].keys():
+                number = config.COLLECTIONS[self._selected_collection_id]['expressions']
+                message = message + '\n<li> ' + str(config.COLLECTIONS[self._selected_collection_id]['expressions']) + ' expression file'
+                if number > 1:
+                    message = message + 's'
             if 'processing' in config.COLLECTIONS[self._selected_collection_id].keys():
                 number = config.COLLECTIONS[self._selected_collection_id]['processing']
                 message = message + '\n<li> ' + str(number) + ' processing script'

resource_sharing/repository_manager.py

@@ -305,7 +305,7 @@ def edit_directory(
                                 collection['status'] = COLLECTION_INSTALLED_STATUS
                                 # Keep the collection statistics
                                 for key in installed_collection.keys():
-                                    if key in ['models', 'processing', 'rscripts', 'style', 'svg', 'symbol']:
+                                    if key in ['models', 'processing', 'rscripts', 'style', 'svg', 'symbol', 'expressions']:
                                         collection[key] = installed_collection[key]
 
                             else:

resource_sharing/resource_handler/__init__.py

@@ -5,3 +5,4 @@
 from .style_handler import StyleResourceHandler
 from .r_handler import RScriptHandler
 from .model_handler import ModelHandler
+from .expression_handler import ExpressionHandler

resource_sharing/resource_handler/expression_handler.py

@@ -0,0 +1,129 @@
+# coding=utf-8
+from pathlib import Path
+import json
+import logging
+
+from qgis.core import QgsSettings
+try:
+    from qgis.core import Qgis
+except ImportError:
+    from qgis.core import QGis as Qgis
+
+from resource_sharing.resource_handler.base import BaseResourceHandler
+from resource_sharing.utilities import (user_expressions_group, repo_settings_group, qgis_version)
+
+hasExprBuilder = False
+#try:
+#    from qgis.core import QgsExpressions
+
+try:
+    from qgis.gui import QgsExpressionBuilderWidget
+except:
+    hasExprBuilder = False
+else:
+    hasExprBuilder = True
+
+LOGGER = logging.getLogger('QGIS Resource Sharing')
+EXPRESSIONS = 'expressions'
+
+class ExpressionHandler(BaseResourceHandler):
+    """Concrete class of the Expression handler."""
+    IS_DISABLED = False
+
+    def __init__(self, collection_id):
+        """Constructor of the base class."""
+        BaseResourceHandler.__init__(self, collection_id)
+        # Initialize with the QGIS settings????
+
+    @classmethod
+    def dir_name(self):
+        return EXPRESSIONS
+
+    def install(self):
+        """Add the expressions from this collection to QGIS settings.
+        """
+        LOGGER.info("Installing expressions")
+        #return
+        # Skip installation if the directory does not exist
+        if not Path(self.resource_dir).exists():
+            return
+
+        # Uninstall first (in case it is a reinstall)
+        #self.uninstall()
+
+        # Get all the expressions in the collection
+        json_files = []
+        valid = 0
+        for item in Path(self.resource_dir).glob('*'):
+            if item.suffix.lower().endswith("json"):
+                file_path = Path(self.resource_dir, item)
+                json_files.append(file_path)
+        # If there are no json files, there is nothing to do
+        if len(json_files) == 0:
+            return
+        settings = QgsSettings()
+        settings.beginGroup(user_expressions_group())
+        for json_file in json_files:
+            namePrefix = json_file.stem + '_'
+            LOGGER.info("Installing expressions from " + str(json_file))
+
+            with open(json_file, 'rb') as expr_file:
+                expr_json = expr_file.read()
+            jsontext = json.loads(expr_json)
+
+            #QgsExpressionBuilderWidget loadExpressionsFromJson
+
+            expressions = jsontext['expressions']
+            for expr in expressions:
+                expr_name = namePrefix + expr['name']
+                LOGGER.info("Expr. name: " + expr_name)
+                expr_value =expr['expression']
+                LOGGER.info("Expr. expression: " + expr_value)
+                expr_help = expr['description']
+                LOGGER.info("Expr. description: " + expr_help)
+
+                settings.setValue(expr_name + '/expression', expr_value)
+                settings.setValue(expr_name + '/helpText', expr_help)
+                aftervalue = settings.value(expr_name + '/expression', '', type=unicode).strip()
+                LOGGER.info("after - expr: " + aftervalue)
+            valid += 1
+        settings.endGroup()
+        if valid >= 0:
+            self.collection[EXPRESSIONS] = valid
+
+    def uninstall(self):
+        """Remove the expressions in this collection from QGIS settings.
+        """
+
+        # Remove from settings
+        LOGGER.info("Removing expressions")
+        # Skip removal if the directory does not exist
+        if not Path(self.resource_dir).exists():
+            return
+        # Get all the expressions in the collection
+        json_files = []
+        for item in Path(self.resource_dir).glob('*'):
+            if item.suffix.lower().endswith("json"):
+                file_path = Path(self.resource_dir, item)
+                json_files.append(file_path)
+        # If there are no json files, there is nothing to do
+        if len(json_files) == 0:
+            return
+        settings = QgsSettings()
+        settings.beginGroup(user_expressions_group())
+        for json_file in json_files:
+            namePrefix = json_file.stem + '_'
+            LOGGER.info("Removing expressions from " + str(json_file))
+            with open(json_file, 'rb') as expr_file:
+                expr_json = expr_file.read()
+            jsontext = json.loads(expr_json)
+            expressions = jsontext['expressions']
+            for expr in expressions:
+                expr_name = namePrefix + expr['name']
+                LOGGER.info("Expr. name: " + expr_name)
+                if settings.contains(expr_name + '/expression'):
+                   LOGGER.info("Exists - removing")
+                   settings.remove(expr_name)
+        settings.endGroup()
+        # Remove files - nothing to remove
+

resource_sharing/utilities.py

@@ -51,6 +51,11 @@ def ui_path(*args):
     return path
 
 
+def user_expressions_group():
+    """Get the user expressions group."""
+    return '/expressions/user'
+
+
 def repo_settings_group():
     """Get the settings group for Resource Sharing Dialog."""
     return '/ResourceSharing/repository'