Resolve relative URLs in settings/config to same host:port

If `FlagsURLs` and/or `PostResult` are specified as relative URLs, then
the same `scheme://host:port` will be prepended to which the request was
issued that caused these files to be served.

Closes: #2

Author: madduck

tptools/ext/squore/assets/config.toml

@@ -4,9 +4,10 @@
 shareAction = "PostResult"
 
 # If shareAction == "PostResult", the URL where to POST the results.
-# Use the special value "me" such that results are posted back to tpsrv.
+# If specified as a relative URL, the same scheme/host/port will be used to which the client
+# send the request.
 # TODO: interaction with MQTT?
-PostResult = "http://tc/tptools/v1/squore/result"
+PostResult = "/tptools/v1/squore/result"
 
 # What to POST to the URL:
 # https://github.com/obbimi/Squore/blob/master/src/com/doubleyellow/scoreboard/prefs/PostDataPreference.java

tptools/ext/squore/assets/settings.json

@@ -1,7 +1,7 @@
 {
   "BackKeyBehaviour": "UndoScore",
   "FCMEnabled": false,
-  "FlagsURLs": "http://tc/squore/v1/flags/%1$s.png",
+  "FlagsURLs": "/squore/v1/flags/%1$s.png",
   "MQTTBrokerURL": "Custom",
   "MQTTBrokerURL_Custom": "mqtt://mqtt",
   "MQTTPublishJoinerLeaverTopic": "tptools/${Brand}/JoinerLeaver",

tptools/tpsrv/squoresrv.py

@@ -215,16 +215,35 @@ def get_devmap_path(request: Request) -> pathlib.Path | Never:
         ) from err
 
 
+def _relative_to_absolute_urls(urls_per_line: str, myurl: URL) -> str:
+    urls: list[str] = []
+    for urlstr in urls_per_line.splitlines():
+        if URL(urlstr).is_absolute():
+            continue
+        urls.append(str(myurl.with_path(urlstr, encoded=True)))
+    return "\n".join(urls)
+
+
 def get_settings(
     path: Annotated[pathlib.Path, Depends(get_settings_path)],
+    myurl: Annotated[URL, Depends(get_url)],
 ) -> dict[str, Any] | Never:
     try:
         with open(path, "rb") as f:
             # TODO:cache. There should be a file-like class that caches the output,
             # ideally even the output of a callable on the data, and on every
             # subsequent access, check the original file's mtime to decide whether
             # to serve the cache, or relaod.
-            return cast(dict[str, Any], json.load(f))
+
+            settings: dict[str, Any] = json.load(f)
+
+            for setting in ("FlagsURLs",):
+                if setting in settings:
+                    settings[setting] = _relative_to_absolute_urls(
+                        settings[setting], myurl
+                    )
+
+            return settings
 
     except FileNotFoundError as err:
         raise HTTPException(
@@ -235,6 +254,7 @@ def get_settings(
 
 def get_config(
     path: Annotated[pathlib.Path, Depends(get_config_path)],
+    myurl: Annotated[URL, Depends(get_url)],
 ) -> Config | Never:
     config: Config = {}
 
@@ -259,6 +279,10 @@ def get_config(
                     detail=f"Invalid key in config file {path}: {key}",
                 )
 
+    for setting in ("PostResult",):
+        if setting in config:
+            config[setting] = _relative_to_absolute_urls(config[setting], myurl)
+
     return config