feat: allow CLI to find a different port - WF-76

docs/framework/chat-assistant.mdx

@@ -49,7 +49,7 @@ Next, open your terminal and navigate to the directory where you want to create
     This command sets up a new project called `chat-assistant` in the specified directory.
   </Step>
   <Step title="Edit your project">
-    To edit your project, run the below commands. This will bring up the console, where Framework-wide messages and errors will appear, including logs from the API. By default, the Writer Framework Builder is accessible at `localhost:3006`. If that port is in use, you can specify a different port. Open this address in your browser to view your default application setup.
+    To edit your project, run the below commands. This will bring up the console, where Framework-wide messages and errors will appear, including logs from the API. By default, the Writer Framework Builder is accessible at `localhost:4005`. If that port is in use, you can specify a different port. Open this address in your browser to view your default application setup.
 
     <CodeGroup>
     ```bash Standard port
@@ -151,4 +151,4 @@ Once the application is deployed, the CLI will return with the URL of your live
 
 ## Conclusion
 
-That's all it takes to set up a basic application with the Writer Framework. This setup not only demonstrates the platform's capabilities, but also provides a foundation on which you can build more complex applications. To learn more, explore the rest of the Writer Framework documentation and the API documentation. 
+That's all it takes to set up a basic application with the Writer Framework. This setup not only demonstrates the platform's capabilities, but also provides a foundation on which you can build more complex applications. To learn more, explore the rest of the Writer Framework documentation and the API documentation. 

docs/framework/product-description-generator.mdx

@@ -51,15 +51,15 @@ Next, open your terminal and navigate to the directory where you want to create
     This command sets up a new project called `product-description-app` in the specified directory using a template designed for this tutorial.
   </Step>
   <Step title="Edit your project">
-    To edit your project, run the below commands. This will bring up the console, where Framework-wide messages and errors will appear, including logs from the API. By default, the Writer Framework Builder is accessible at `localhost:3006`. If that port is in use, you can specify a different port. Open this address in your browser to view your default application setup.
+    To edit your project, run the below commands. This will bring up the console, where Framework-wide messages and errors will appear, including logs from the API. By default, the Writer Framework Builder is accessible at `localhost:4005`. If that port is in use, you can specify a different port. Open this address in your browser to view your default application setup.
 
     <CodeGroup>
     ```bash Standard port
      writer edit product-description-app
     ```
 
     ```bash Custom port
-     writer edit product-description-app –port=3007
+     writer edit product-description-app --port=3007
     ```
     </CodeGroup>
   </Step>
@@ -377,4 +377,4 @@ Once the application is deployed, the CLI will return with the URL of your live
 
 ## Conclusion
 
-You’ve now built a full application with the Writer Framework and the Writer AI module. Congratulations! This application not only demonstrates the platform's capabilities but also provides a foundation on which you can build more complex applications. To learn more, explore the rest of the Writer Framework documentation and the API documentation.
+You’ve now built a full application with the Writer Framework and the Writer AI module. Congratulations! This application not only demonstrates the platform's capabilities but also provides a foundation on which you can build more complex applications. To learn more, explore the rest of the Writer Framework documentation and the API documentation.

docs/framework/quickstart-tutorial.mdx

@@ -47,7 +47,7 @@ Once this is done, we can finally run the Framework editor using the command:
 writer edit .
 ```
 
-This will run our Framework instance. Runtime logs can be observed in the terminal, and the app is available at http://localhost:3006.
+This will run our Framework instance. Runtime logs can be observed in the terminal, and the app is available at http://localhost:4005.
 
 ![newly created application](./images/quickstart/new_app.png)
 

docs/framework/quickstart.mdx

@@ -61,6 +61,10 @@ It's not recommended to expose Framework to the Internet. If you need to access
 If you need to disable this protection, use the flag `--enable-remote-edit`. 
 </Warning>
 
+<Info>
+The editor starts by default on port 4005. If you launch multiple editors in parallel and do not specify a port, Writer Framework will automatically assign the next port until reaching the limit of 4099.
+</Info>
+
 ## Run an app
 
 When your app is ready, execute the `run` command, which will allow others to run, but not edit, your Framework app.
@@ -69,6 +73,10 @@ When your app is ready, execute the `run` command, which will allow others to ru
 writer run my_app
 ```
 
+<Info>
+Your app starts by default on port 3005. If you launch multiple apps in parallel and do not specify a port, Writer Framework will automatically assign the next port until reaching the limit of 3099.
+</Info>
+
 You can specify a port and host. Specifying `--host 0.0.0.0` enables you to share your application in your local network.
 
 ```sh

docs/framework/release-notes-generator.mdx

@@ -48,7 +48,7 @@ Next, open your terminal and navigate to the directory where you want to create
     ```
   </Step>
   <Step title="Edit your project">
-    To edit your project, run the following commands. This will bring up the console, which displays Framework-wide messages and errors, including logs from the API. By default, the Writer Framework Builder is accessible at `localhost:3006`. If this port is in use, you can specify a different port. Open this address in your browser to view your default application setup.
+    To edit your project, run the following commands. This will bring up the console, which displays Framework-wide messages and errors, including logs from the API. By default, the Writer Framework Builder is accessible at `localhost:4005`. If this port is in use, you can specify a different port. Open this address in your browser to view your default application setup.
 
     <CodeGroup>
     ```bash Standard port
@@ -422,4 +422,4 @@ You'll be prompted for your API key.
 Once the application is deployed, the CLI will return with the URL of your live application.
 
 ## Conclusion
-By following these steps, you've created a complete Release notes generator application using Writer Framework. To learn more, explore the rest of the Writer Framework documentation and the API documentation.
+By following these steps, you've created a complete Release notes generator application using Writer Framework. To learn more, explore the rest of the Writer Framework documentation and the API documentation.

docs/framework/social-post-generator.mdx

@@ -51,15 +51,15 @@ Next, open your terminal and navigate to the directory where you want to create
     This command will set up a new project called `social-generator` in the specified directory using an `ai-starter` template.
   </Step>
   <Step title="Edit project">
-    To edit your project, run the below commands. This will bring up the console, where Framework-wide messages and errors will appear, including logs from the API. By default, the Writer Framework Builder is accessible at `localhost:3006`. If that port is in use, you can specify a different port. Open this address in your browser to view your default application setup.
+    To edit your project, run the below commands. This will bring up the console, where Framework-wide messages and errors will appear, including logs from the API. By default, the Writer Framework Builder is accessible at `localhost:4005`. If that port is in use, you can specify a different port. Open this address in your browser to view your default application setup.
 
     <CodeGroup>
     ```bash Standard port
     writer edit social-generator
     ```
 
     ```bash Custom port
-    writer edit social-generator –port=3007
+    writer edit social-generator --port=3007
     ```
     </CodeGroup>
   </Step>
@@ -216,4 +216,4 @@ Once the application is deployed, the CLI will return with the URL of your live
 
 ## Conclusion
 
-That's all it takes to set up a basic application with the Writer Framework. This setup not only demonstrates the platform's capabilities but also provides a foundation on which you can build more complex applications. To learn more, explore the rest of the Writer Framework documentation and the API documentation. 
+That's all it takes to set up a basic application with the Writer Framework. This setup not only demonstrates the platform's capabilities but also provides a foundation on which you can build more complex applications. To learn more, explore the rest of the Writer Framework documentation and the API documentation. 

src/writer/command_line.py

@@ -20,9 +20,9 @@ def main():
 
 @main.command()
 @click.option('--host', default="127.0.0.1", help="Host to run the app on")
-@click.option('--port', default=3005, help="Port to run the app on")
+@click.option('--port', default=None, help="Port to run the app on")
 @click.argument('path')
-def run(path, host, port):
+def run(path: str, host: str, port: Optional[int]):
     """Run the app from PATH folder in run mode."""
 
     abs_path = os.path.abspath(path)
@@ -34,11 +34,11 @@ def run(path, host, port):
 
 @main.command()
 @click.option('--host', default="127.0.0.1", help="Host to run the app on")
-@click.option('--port', default=3006, help="Port to run the app on")
+@click.option('--port', default=None, help="Port to run the app on")
 @click.option('--enable-remote-edit', help="Set this flag to allow non-local requests in edit mode.", is_flag=True)
 @click.option('--enable-server-setup', help="Set this flag to enable server setup hook in edit mode.", is_flag=True)
 @click.argument('path')
-def edit(path, port, host, enable_remote_edit, enable_server_setup):
+def edit(path: str, port: Optional[int], host: str, enable_remote_edit: bool, enable_server_setup: bool):
     """Run the app from PATH folder in edit mode."""
 
     abs_path = os.path.abspath(path)
@@ -63,9 +63,9 @@ def create(path, template):
 
 @main.command()
 @click.option('--host', default="127.0.0.1", help="Host to run the app on")
-@click.option('--port', default=3006, help="Port to run the app on")
+@click.option('--port', default=None, help="Port to run the app on")
 @click.option('--enable-remote-edit', help="Set this flag to allow non-local requests in edit mode.", is_flag=True)
-def hello(port, host, enable_remote_edit):
+def hello(port: Optional[int], host: str, enable_remote_edit):
     """Create and run an onboarding 'Hello' app."""
     create_app("hello", template_name="hello", overwrite=True)
     writer.serve.serve("hello", mode="edit",

src/writer/serve.py

@@ -5,6 +5,7 @@
 import os
 import os.path
 import pathlib
+import socket
 import textwrap
 import typing
 from contextlib import asynccontextmanager
@@ -500,7 +501,7 @@ def register_auth(
 ):
     auth.register(app, callback=callback, unauthorized_action=unauthorized_action)
 
-def serve(app_path: str, mode: ServeMode, port, host, enable_remote_edit=False, enable_server_setup=False):
+def serve(app_path: str, mode: ServeMode, port: Optional[int], host, enable_remote_edit=False, enable_server_setup=False):
     """ Initialises the web server. """
 
     print_init_message()
@@ -513,6 +514,14 @@ def on_load():
     Loading of the server_setup.py is active by default 
     when Writer Framework is launched with the run command.
     """
+    if port is None:
+        mode_allowed_ports = {
+            'run': (3005, 3099),
+            'edit': (4005, 4099)
+        }
+
+        port = _next_localhost_available_port(mode_allowed_ports[mode])
+
     enable_server_setup = mode == "run" or enable_server_setup
     app = get_asgi_app(app_path, mode, enable_remote_edit, on_load=on_load, enable_server_setup=enable_server_setup)
     log_level = "warning"
@@ -599,17 +608,6 @@ def _mount_server_static_path(app: FastAPI, server_static_path: pathlib.Path) ->
         if f.is_dir():
             app.mount(f"/{f.name}", StaticFiles(directory=f), name=f"server_static_{f}")
 
-def _execute_server_setup_hook(user_app_path: str) -> None:
-    """
-    Runs the server_setup.py module if present in the application directory.
-
-    """
-    server_setup_path = os.path.join(user_app_path, "server_setup.py")
-    if os.path.isfile(server_setup_path):
-        spec = cast(ModuleSpec, importlib.util.spec_from_file_location("server_setup", server_setup_path))
-        module = importlib.util.module_from_spec(spec)
-        spec.loader.exec_module(module)  # type: ignore
-
 
 def app_runner(asgi_app: WriterFastAPI) -> AppRunner:
     return asgi_app.state.app_runner
@@ -632,3 +630,34 @@ def wf_root_static_assets() -> List[pathlib.Path]:
         all_static_assets.append(f)
 
     return all_static_assets
+
+
+def _execute_server_setup_hook(user_app_path: str) -> None:
+    """
+    Runs the server_setup.py module if present in the application directory.
+
+    """
+    server_setup_path = os.path.join(user_app_path, "server_setup.py")
+    if os.path.isfile(server_setup_path):
+        spec = cast(ModuleSpec, importlib.util.spec_from_file_location("server_setup", server_setup_path))
+        module = importlib.util.module_from_spec(spec)
+        spec.loader.exec_module(module)  # type: ignore
+
+
+def _next_localhost_available_port(port_range: Tuple[int, int]) -> int:
+    """
+    Searches for a free port in a given range on localhost to start the server
+
+    >>> port = _next_localhost_available_port((3005, 3099))
+
+    3005 is the first port to be tested. If it is not available, the port 3006 is tested, and so on.
+    """
+    for port in range(port_range[0], port_range[1]):
+        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        sock.settimeout(1)
+        result = sock.connect_ex(('127.0.0.1', port))
+        sock.close()
+        if result != 0:
+            return port
+
+    raise OSError(f"No free port found to start the server between {port_range[0]} and {port_range[1]} .")