check for non-2xx, cache any 2xx responses that pass minimal validation

1 files changed, 26 insertions, 15 deletions

diff --git a/packages/anastasis-webui/src/pages/home/AddingProviderScreen/index.ts b/packages/anastasis-webui/src/pages/home/AddingProviderScreen/index.ts
index 5f49f39e8..365d2e8e7 100644
--- a/packages/anastasis-webui/src/pages/home/AddingProviderScreen/index.ts
+++ b/packages/anastasis-webui/src/pages/home/AddingProviderScreen/index.ts
@@ -65,27 +65,37 @@ const map: StateViewMap<State> = {
 
 export default compose("AddingProviderScreen", useComponentState, map);
 
+const providerResponseCache = new Map<string, any>(); // `any` is the return type of res.json()
 export async function testProvider(
   url: string,
   expectedMethodType?: string,
 ): Promise<void> {
   try {
     // TODO: look into using core.getProviderInfo :)
-    const json = await fetch(new URL("config", url).href)
-      .catch((error) => {
-        console.error("Provider HTTP Error:", error);
-        throw new Error(
-          "Encountered a fatal error whilst testing the provider: " + url,
-        );
-      })
-      .then((response) =>
-        response.json().catch((error) => {
-          console.error("Provider Parsing Error:", error);
-          throw new Error(
-            "Encountered a fatal error whilst testing the provider: " + url,
-          );
-        }),
-      );
+    const providerHasUrl = providerResponseCache.has(url);
+    const json = providerHasUrl
+      ? providerResponseCache.get(url)
+      : await fetch(new URL("config", url).href)
+          .catch((error) => {
+            console.error("Provider HTTP Error:", error);
+            throw new Error(
+              "Encountered a fatal error whilst testing the provider: " + url,
+            );
+          })
+          .then(async (response) => {
+            if (!response.ok)
+              throw new Error(
+                `The server ${response.url} responded with a non-2xx response.`,
+              );
+            try {
+              return await response.json();
+            } catch (error) {
+              console.error("Provider Parsing Error:", error);
+              throw new Error(
+                "Encountered a fatal error whilst testing the provider: " + url,
+              );
+            }
+          });
     if (typeof json !== "object")
       throw new Error(
         "Encountered a fatal error whilst testing the provider: " +
@@ -102,6 +112,7 @@ export async function testProvider(
         "This provider doesn't have authentication method. Please check the provider's URL and ensure it is properly configured.",
       );
     }
+    if (!providerHasUrl) providerResponseCache.set(url, json);
     if (!expectedMethodType) {
       return;
     }