More flexible canister url script

README.md

@@ -19,8 +19,9 @@ If prompted, proceed by installing the recommended plugins for VS Code.
 ### Running your Project
 
 After the IDE has opened, run `dfx deploy` in the terminal to deploy the frontend and backend. 
-Click on the first green link at the end of the output to see your canister's frontend in the browser. 
-**NOTE**: If the printed link does not work when developing remotely (in a web browser), run `./scripts/canister_url.sh` and click the link that is shown there.
+Click on the first green link at the end of the output to see your canister's frontend in the browser.
+To interact with the backend canister, click on the second green link.
+**NOTE**: When developing in GitHub Codespaces, run `./scripts/canister_urls.py` and use the links that are shown there.
 
 For interactive development of the frontend canister, you can also start a node server by running `npm start`.
 You can find your canister's frontend running under http://localhost:8080.

scripts/canister_urls.py

@@ -0,0 +1,45 @@
+#!/usr/bin/python3
+
+import json
+from os import environ, path
+
+GREEN='\033[1;32m'
+NORMAL='\033[0m'
+BOLD='\033[1m'
+
+def get_host():
+    if 'GITHUB_CODESPACES_PORT_FORWARDING_DOMAIN' in environ:
+        return f"https://{environ['CODESPACE_NAME']}-4943.{environ['GITHUB_CODESPACES_PORT_FORWARDING_DOMAIN']}"
+    else:
+        return 'http://127.0.0.1:4943'
+
+if __name__ == "__main__":
+    root_path = path.dirname(path.realpath(__file__))
+    canister_id_file = f'{root_path}/../.dfx/local/canister_ids.json';
+    if not path.exists(canister_id_file):
+        print(f"Run 'dfx deploy' first.")
+        exit(1)
+    with open(canister_id_file) as f:
+        data = json.load(f)
+        frontend_canisters = []
+        backend_canisters = []
+
+        for key, value in data.items():
+            if key == '__Candid_UI':
+                candid_ui_canister_id = value['local']
+            elif 'frontend' in key:
+                frontend_canisters.append((key, value['local']))
+            else:
+                backend_canisters.append((key, value['local']))
+
+        host = get_host()
+
+        print(f"{BOLD}URLs:{NORMAL}")
+        if frontend_canisters:
+            print(f"""{BOLD}  Frontend canister via browser{NORMAL}""")
+            for name, id in frontend_canisters:
+                print(f"{BOLD}    {name}: {GREEN}{host}/?canisterId={id}{NORMAL}")
+        if backend_canisters:
+            print(f"{BOLD}  Backend canister via Candid interface:")
+            for name, id in backend_canisters:
+                print(f"{BOLD}    {name}: {GREEN}{host}/?canisterId={candid_ui_canister_id}&id={id}{NORMAL}")