Merge pull request #49 from unyt-org/feat-update-dx-config

Update dx config

docs/manual/03 Pointers.md

@@ -154,7 +154,7 @@ Read more about transform functions in the chapter [Functional Programming](./09
 
 ## Using effects
 
-With transform functions, value can be defined declaratively.
+With transform functions, values can be defined declaratively.
 Still, there are some scenarios where the actual pointer value change event must be handled with custom logic.
 For this scenario, the `effect()` function can be used.
 
@@ -245,6 +245,32 @@ it is garbage colleted and the effect is removed.
 
 Weak value bindings can be used with all *object* values, not just with pointers.
 
+### Async effects
+
+Effect callbacks cannot be `async` functions.
+To handle async operations, you can always call an async function from inside the
+effect callback:
+
+```ts
+const searchName = $$("");
+const searchAge = $$(18);
+
+// async function that searches for a user and shows the result somewhere
+async function searchUser(name: string, age: number) {
+    const user = await query({type: "user", name, age});
+    showUser(user);
+}
+
+// effect that triggers the user search every time searchName or searchAge is changed
+effect(() => searchUser(searchName.val, searchAge.val))
+```
+
+All dependency values of the effect must be accessed synchronously.
+This means that the variables inside the async function don't trigger the effect, only the ones passed
+into the `searchUser` call.
+
+
+
 ## Observing pointer changes
 
 For more fine grained control, the `observe()` function can be used to handle pointer value updates.

runtime/endpoint_config.ts

@@ -94,21 +94,29 @@ class EndpointConfig implements EndpointConfigData {
 				config = <EndpointConfigData> await Runtime.executeDatexLocally(serialized, undefined, undefined, globalThis.location?.href ? new URL(globalThis.location.href) : undefined)
 			}
 			// try to get from .dx url
-			else {
-				if (!path) path = new URL('/'+this.DX_FILE_NAME, globalThis.location.href)
-				try {
-					config = await datex.get(path);
+			if (!path) path = new URL('/'+this.DX_FILE_NAME, globalThis.location.href)
+			try {
+				const configUpdate = await datex.get<EndpointConfigData>(path);
+				if (!config) {
+					config = configUpdate;
 					logger.info("loaded endpoint config from " + path);
 				}
-				catch (e) {
-					// ignore if no .dx file found
-					if (!(await fetch(path)).ok) {}
-					else {
-						logger.error `Could not read config file ${path}: ${e.toString()}`;
-						throw "invalid config file"
+				else {
+					for (const [key, value] of DatexObject.entries(configUpdate as Record<string|symbol,unknown>)) {
+						DatexObject.set(config as Record<string|symbol,unknown>, key as string, value);
 					}
+					logger.debug("updated endpoint config from " + path);
+				}
+			}
+			catch (e) {
+				// ignore if no .dx file found
+				if (!(await fetch(path)).ok) {}
+				else {
+					logger.error `Could not read config file ${path}: ${e.toString()}`;
+					throw "invalid config file"
 				}
 			}
+
 		}
 		else {
 			logger.debug("Cannot load endpoint config file for client type '" + client_type + "'")