feat(config, main, utils): add SERVER mode, unify backend and fronten…

…d config

config.yaml

@@ -4,10 +4,10 @@ production_mode: false
 learning_materials: ./learning_assets
 experiment_implementation: ./tests/model
 experiment_results: ./tests/model/results
-backend_address: 127.0.0.1 # Change also in frontend/src/lib/config.js
-backend_port: 8000 # Change also in frontend/src/lib/config.js
+protocol: http # Either `http` or `https`
+backend_address: 127.0.0.1
+backend_port: 8000
 frontend_address: 127.0.0.1
 frontend_port: 3000
-protocol: http # Either `http` or `https`
 question_generation_model: t5
 natural_language_inference_model: roberta

knowledge_verificator/main.py

@@ -9,6 +9,32 @@
 from knowledge_verificator.command_line import run_cli_mode
 from tests.model.runner import ExperimentRunner
 
+
+def run_backend() -> None:
+    """Run the HTTP backend of the system."""
+    import uvicorn
+
+    uvicorn.run(
+        'knowledge_verificator.backend:ENDPOINTS',
+        host=config().backend_address,
+        port=config().backend_port,
+        reload=(not config().production_mode),
+    )
+
+
+def run_frontend() -> subprocess.Popen:
+    """Run the built-in frontend of the system."""
+    arguments = [
+        'npm',
+        'run',
+        'dev',
+        '--',
+        '--port',
+        str(config().frontend_port),
+    ]
+    return subprocess.Popen(args=arguments, cwd='frontend')
+
+
 if __name__ == '__main__':
     match config().mode:
         case OperatingMode.EXPERIMENT:
@@ -20,22 +46,9 @@
         case OperatingMode.CLI:
             run_cli_mode()
 
+        case OperatingMode.SERVER:
+            run_backend()
+
         case OperatingMode.CLIENT_SERVER:
-            import uvicorn
-
-            arguments = [
-                'npm',
-                'run',
-                'dev',
-                '--',
-                '--port',
-                str(config().frontend_port),
-            ]
-            frontend = subprocess.Popen(args=arguments, cwd='frontend')
-
-            uvicorn.run(
-                'knowledge_verificator.backend:ENDPOINTS',
-                host=config().backend_address,
-                port=config().backend_port,
-                reload=(not config().production_mode),
-            )
+            run_frontend()
+            run_backend()

knowledge_verificator/utils/configuration_parser.py

@@ -27,11 +27,15 @@ class OperatingMode(Enum):
     - CLIENT_SERVER - an HTTP server is started, which serves as the
         backend. Graphical user interface (GUI) in a form of webpage
         is served as the frontend.
+    - SERVER - an HTTP server is started as an API. The built-in
+        frontend is not used. This is useful if one wants to build
+        a custom frontend for the existing backend.
     """
 
     EXPERIMENT = 'EXPERIMENT'
     CLI = 'CLI'
     CLIENT_SERVER = 'CLIENT_SERVER'
+    SERVER = 'SERVER'
 
 
 @dataclass
@@ -118,11 +122,40 @@ class ConfigurationParser:
     """Class, which loads and parses a YAML configuration."""
 
     def __init__(self, configuration_file: Path) -> None:
-        """Load a YAML configuration file."""
+        """
+        Load a YAML configuration file and, optionally, re-create a JS file
+        with the most current configuration.
+        """
         self._config_file: Path | None = None
         self._config_data: dict = {}
         self.load_configuration(configuration_file)
 
+        # Update configuration for the built-in frontend only.
+        if self._config_data['mode'] == OperatingMode.CLIENT_SERVER:
+            self.update_javascript_configuration(
+                Path('frontend/src/lib/config.js')
+            )
+
+    def update_javascript_configuration(self, js_config: Path) -> None:
+        """
+        Re-create a JavaScript configuration file to be compliant
+        with a YAML configuration.
+
+        Create a JavaScript configuration file with a constant API_URL, which
+        supplies an URL to backend for the frontend.
+
+        Args:
+            js_config (Path): Path to a JavaScript configuration file.
+        """
+
+        backend_address = self._config_data['backend_address']
+        backend_port = self._config_data['backend_port']
+        protocol = self._config_data['protocol']
+        js_config_content = f"export const API_URL = '{protocol}://{backend_address}:{backend_port}'; // Do not edit manually."
+
+        with open(js_config.resolve(), 'wt', encoding='utf-8') as fd:
+            fd.write(js_config_content)
+
     def parse_configuration(self) -> Configuration:
         """
         Parse the previously loaded YAML configuration file to an instance