Improve [Explicit] [LLM APIs] [Text Moderation] Error Handling (#290)

* Feat [Explicit] [LLM APIs] [Text Moderation] Error Handling

- [+] feat(textmoderation.ts): improve error handling for moderation responses
- [+] feat(textmoderation.ts): add content type check for moderation responses

* Refactor [Explicit] [LLM APIs] [OpenAI] Display Error Messages

- [+] feat(openai.ts): add error handling for text moderation
- [+] refactor(openai.ts): improve error message display for text moderation

app/client/platforms/openai.ts

@@ -128,16 +128,38 @@ export class ChatGPTApi implements LLMApi {
 
     // Check if text moderation is enabled and required
     if (textmoderation !== false &&
-        options.whitelist !== true &&
-        checkprovider !== ServiceProvider.Azure &&
-        textToModerate) { // Ensure textToModerate is not empty
-      // Call the moderateText method and handle the result
-      const moderationResult = await moderateText(moderationPath, textToModerate, OpenaiPath.TextModerationModels.latest);
-      if (moderationResult) {
-        options.onFinish(moderationResult); // Finish early if moderationResult is not null
+      options.whitelist !== true &&
+      checkprovider !== ServiceProvider.Azure &&
+      textToModerate) { // Ensure textToModerate is not empty
+      try {
+        // Call the moderateText method and handle the result
+        const moderationResult = await moderateText(moderationPath, textToModerate, OpenaiPath.TextModerationModels.latest);
+        if (moderationResult) {
+          options.onFinish(moderationResult); // Finish early if moderationResult is not null
+          return;
+        }
+      } catch (error) {
+        // Handle errors from moderateText
+        let errorMessage = 'An unknown error occurred during text moderation.';
+        if (error instanceof Error) {
+          errorMessage = error.message;
+          try {
+            // Attempt to parse the error message as JSON
+            const errorObj = JSON.parse(errorMessage.substring(errorMessage.indexOf('{')));
+            // Pretty-print the JSON error message
+            errorMessage = prettyObject(errorObj);
+          } catch {
+            // If parsing or formatting fails, use the original error message
+          }
+        }
+        // Format the error message for user-friendly display
+        const formattedError = `We encountered an issue while reviewing your message:\n${errorMessage}`;
+        // Use the onFinish callback or similar to display the error in the chat interface
+        options.onFinish(formattedError);
         return;
       }
     }
+
     const messages = options.messages.map((v) => ({
       role: v.role,
       content: visionModel ? v.content : getMessageTextContent(v),

app/client/platforms/textmoderation.ts

@@ -48,8 +48,13 @@ export async function sendModerationRequest(
         });
 
         if (!moderationResponse.ok) {
-            // Handle non-2xx responses
-            throw new Error(`[${moderationResponse.status}] Failed to get moderation response`);
+            const errorBody = await moderationResponse.text(); // Attempt to read the response body
+            throw new Error(`[${moderationResponse.status}] Failed to get moderation response: ${errorBody}`);
+        }
+
+        const contentType = moderationResponse.headers.get("Content-Type");
+        if (!contentType || !contentType.includes("application/json")) {
+            throw new Error("Unexpected content type received from moderation response");
         }
 
         const moderationJson = await moderationResponse.json();