Invalid filenames expression preview

Mergin/plugin.py

@@ -412,7 +412,7 @@ def set_current_workspace(self, workspace):
                 iface.messageBar().pushMessage(
                     "Mergin Maps",
                     "Your attention is required. Please visit the "
-                    f"<a href='{self.mc.url}/dashboard?utm_source=plugin&utm_medium=attention-required'>"
+                    f"<a href='{self.mc.url}/dashboard?utm_source=plugin&utm_medium=attention-required&workspace={workspace_id}'>"
                     "Mergin dashboard</a>",
                     level=Qgis.Critical,
                     duration=0,

Mergin/project_settings_widget.py

@@ -30,6 +30,7 @@
     set_tracking_layer_flags,
     is_experimental_plugin_enabled,
     remove_prefix,
+    invalid_filename_character,
 )
 
 ui_file = os.path.join(os.path.dirname(os.path.realpath(__file__)), "ui", "ui_project_config.ui")
@@ -224,14 +225,21 @@ def update_preview(self, expression, layer, field_name):
         exp = QgsExpression(expression)
         exp.prepare(context)
         if exp.hasParserError():
-            self.label_preview.setText(f"<i>{exp.parserErrorString()}</i>")
+            self.label_preview.setText(f"{exp.parserErrorString()}")
             return
 
         val = exp.evaluate(context)
         if exp.hasEvalError():
-            self.label_preview.setText(f"<i>{exp.evalErrorString()}</i>")
+            self.label_preview.setText(f"{exp.evalErrorString()}")
             return
-
+        if val:
+            # check if evaluated expression contains invalid filename characters
+            invalid_char = invalid_filename_character(val)
+            if invalid_char:
+                self.label_preview.setText(
+                    f"The file name '{val}.jpg' contains an invalid character. Do not use '{invalid_char}' character in the file name."
+                )
+                return
         config = layer.fields().field(field_name).editorWidgetSetup().config()
         target_dir = resolve_target_dir(layer, config)
         prefix = prefix_for_relative_path(
@@ -240,9 +248,9 @@ def update_preview(self, expression, layer, field_name):
             target_dir,
         )
         if prefix:
-            self.label_preview.setText(f"<i>{remove_prefix(prefix, QgsProject.instance().homePath())}/{val}.jpg</i>")
+            self.label_preview.setText(f"{remove_prefix(prefix, QgsProject.instance().homePath())}/{val}.jpg")
         else:
-            self.label_preview.setText(f"<i>{val}.jpg</i>")
+            self.label_preview.setText(f"{val}.jpg")
 
     def check_project(self, state):
         """

Mergin/ui/ui_project_config.ui

@@ -193,6 +193,11 @@
               <verstretch>0</verstretch>
              </sizepolicy>
             </property>
+            <property name="font">
+             <font>
+              <italic>true</italic>
+             </font>
+            </property>
             <property name="text">
              <string/>
             </property>
@@ -214,14 +219,14 @@
           <item row="4" column="1">
            <widget class="QLabel" name="label_7">
             <property name="text">
-             <string>Preview</string>
+             <string>Preview:</string>
             </property>
            </widget>
           </item>
           <item row="1" column="1" colspan="2">
            <widget class="QLabel" name="label_6">
             <property name="text">
-             <string>&lt;html&gt;&lt;head/&gt;&lt;body&gt;&lt;p&gt;&lt;span style=&quot; font-weight:600;&quot;&gt;Photo name format&lt;/span&gt;&lt;/p&gt;&lt;p&gt;Set up custom photo names format based on an expression. Make sure that the name is unique for each photo.&lt;/p&gt;&lt;p&gt;Pro tip: use variables like &lt;span style=&quot; font-family:'Noto Sans Mono';&quot;&gt;@mm_user_email&lt;/span&gt;, &lt;span style=&quot; font-family:'Noto Sans Mono';&quot;&gt;@layer_name&lt;/span&gt; or layer fields in combination with &lt;span style=&quot; font-family:'Noto Sans Mono';&quot;&gt;now()&lt;/span&gt; (to get the current time) in order to generate unique photo names.&lt;/p&gt;&lt;p&gt;For further details, please refer to &lt;a href=&quot;https://merginmaps.com/docs/layer/settingup_forms_photo/#customising-photo-name-format-with-expressions&quot;&gt;&lt;span style=&quot; text-decoration: underline; color:#1d99f3;&quot;&gt;our documentation&lt;/span&gt;&lt;/a&gt;.&lt;/p&gt;&lt;/body&gt;&lt;/html&gt;</string>
+             <string>&lt;html&gt;&lt;head/&gt;&lt;body&gt;&lt;p&gt;&lt;span style=&quot; font-weight:600;&quot;&gt;Photo name format&lt;/span&gt;&lt;/p&gt;&lt;p&gt;Set up custom photo names format based on an expression. Make sure that the name is unique for each photo.&lt;/p&gt;&lt;p&gt;Pro tip: use variables like &lt;span style=&quot; font-family:'Noto Sans Mono';&quot;&gt;@mm_user_email&lt;/span&gt;, &lt;span style=&quot; font-family:'Noto Sans Mono';&quot;&gt;@layer_name&lt;/span&gt; or layer fields in combination with &lt;span style=&quot; font-family:'Noto Sans Mono';&quot;&gt;now()&lt;/span&gt; (to get the current time) in order to generate unique photo names.&lt;/p&gt;&lt;p&gt;For further details, please refer to &lt;a href=&quot;https://merginmaps.com/docs/layer/settingup_forms_photo/#customising-photo-name-format-with-expressions&quot;&gt;&lt;span style=&quot; text-decoration: underline; color:#1d99f3;&quot;&gt;our documentation&lt;/span&gt;&lt;/a&gt;.&lt;/p&gt;&lt;p&gt;File names may include letters (A–Z, a–z), numbers (0–9), spaces, dashes (-), and underscores (_).&lt;br&gt;Use '/' only to separate subfolders.&lt;/p&gt;&lt;/body&gt;&lt;/html&gt;</string>
             </property>
             <property name="wordWrap">
              <bool>true</bool>

Mergin/utils.py

@@ -1656,3 +1656,12 @@ def is_experimental_plugin_enabled() -> bool:
     else:
         value = settings.value("plugin-manager/allow-experimental", False)
     return value
+
+
+def invalid_filename_character(filename: str) -> str:
+    """Returns invalid character for the filename"""
+    illegal_filename_chars = re.compile(r'[\x00-\x19<>:|?*"]')
+
+    match = illegal_filename_chars.search(filename)
+    if match:
+        return match.group()

Mergin/validation.py

@@ -27,9 +27,10 @@
     QGIS_NET_PROVIDERS,
     is_versioned_file,
     get_layer_by_path,
+    invalid_filename_character,
 )
 
-INVALID_CHARS = re.compile('[\\\/\(\)\[\]\{\}"\n\r]')
+INVALID_FIELD_NAME_CHARS = re.compile('[\\\/\(\)\[\]\{\}"\n\r]')
 PROJECT_VARS = re.compile("\@project_home|\@project_path|\@project_folder")
 
 
@@ -62,6 +63,7 @@ class Warning(Enum):
     EDITOR_JSON_CONFIG_CHANGE = 26
     EDITOR_DIFFBASED_FILE_REMOVED = 27
     PROJECT_HOME_PATH = 28
+    INVALID_ADDED_FILENAME = 29
 
 
 class MultipleLayersWarning:
@@ -128,6 +130,7 @@ def run_checks(self):
         self.check_datum_shift_grids()
         self.check_svgs_embedded()
         self.check_editor_perms()
+        self.check_filenames()
 
         return self.issues
 
@@ -345,7 +348,7 @@ def check_field_names(self):
             if dp.storageType() == "GPKG":
                 fields = layer.fields()
                 for f in fields:
-                    if INVALID_CHARS.search(f.name()):
+                    if INVALID_FIELD_NAME_CHARS.search(f.name()):
                         self.issues.append(SingleLayerWarning(lid, Warning.INCORRECT_FIELD_NAME))
 
     def check_snapping(self):
@@ -452,6 +455,12 @@ def check_editor_perms(self):
                     url = f"reset_file?layer={path}"
                     self.issues.append(SingleLayerWarning(layer.id(), Warning.EDITOR_DIFFBASED_FILE_REMOVED, url))
 
+    def check_filenames(self):
+        """Checks that files to upload have valid filenames. Otherwise, push will be refused by the server."""
+        for file in self.changes["added"]:
+            if invalid_filename_character(file["path"]):
+                self.issues.append(MultipleLayersWarning(Warning.INVALID_ADDED_FILENAME, file["path"]))
+
 
 def warning_display_string(warning_id, url=None):
     """Returns a display string for a corresponding warning"""
@@ -516,3 +525,5 @@ def warning_display_string(warning_id, url=None):
         return f"You don't have permission to remove this layer. <a href='{url}'>Reset the layer</a> to be able to sync changes."
     elif warning_id == Warning.PROJECT_HOME_PATH:
         return "QGIS Project Home Path is specified. <a href='fix_project_home_path'>Quick fix the issue. (This will unset project home)</a>"
+    elif warning_id == Warning.INVALID_ADDED_FILENAME:
+        return f"You cannot synchronize a file with invalid characters in it's name. Please sanitize the name of this file '{url}'"