Only decode or return JSON or plain text

Author: kmcginnes

packages/graph-explorer/src/connector/fetchDatabaseRequest.test.ts

@@ -14,6 +14,19 @@ describe("decodeErrorSafely", () => {
     expect(decoded).toBeUndefined();
   });
 
+  it("should ignore xml responses", async () => {
+    const response = new Response("<xml></xml>", {
+      status: 500,
+      headers: {
+        "Content-Type": "text/xml",
+      },
+    });
+
+    const decoded = await decodeErrorSafely(response);
+
+    expect(decoded).toBeUndefined();
+  });
+
   it("should return the error message inside the JSON response", async () => {
     const response = new Response(
       JSON.stringify({

packages/graph-explorer/src/connector/fetchDatabaseRequest.ts

@@ -23,37 +23,38 @@ const NeptuneErrorSchema = z.object({
  */
 export async function decodeErrorSafely(response: Response): Promise<any> {
   const contentType = response.headers.get("Content-Type");
-  const contentTypeHasValue = contentType !== null && contentType.length > 0;
-  // Assume missing content type is JSON
-  const isJson =
-    !contentTypeHasValue || contentType.includes("application/json");
-  const isHtml = contentTypeHasValue && contentType.includes("text/html");
+  if (
+    !contentType ||
+    (!contentType.includes("application/json") &&
+      !contentType.includes("text/plain"))
+  ) {
+    return undefined;
+  }
 
   // Extract the raw text from the response
   const rawText = await response.text();
-
-  // Check for empty response
   if (!rawText) {
     return undefined;
-  } else if (isJson) {
+  }
+
+  // Parse JSON
+  if (contentType.includes("application/json")) {
     try {
       // Try parsing the response as JSON
       const data = JSON.parse(rawText);
 
       // Flatten the error if it contains an error object
       return data?.error ?? data;
     } catch (error) {
-      console.error("Failed to decode the error response as JSON", {
+      // Log the error and fallthrough to return the raw text
+      logger.warn("Failed to decode the error response as JSON", {
         error,
         rawText,
       });
-      return rawText;
     }
-  } else if (isHtml) {
-    // Ignore the content of HTML responses
-    return undefined;
   }
 
+  // Just return the whole response as the error
   return { message: rawText };
 }