refactor: merge /api/chat-stream to /api/openai

app/api/chat-stream/route.ts

@@ -1,62 +0,0 @@
-import { createParser } from "eventsource-parser";
-import { NextRequest } from "next/server";
-import { requestOpenai } from "../common";
-
-async function createStream(req: NextRequest) {
-  const encoder = new TextEncoder();
-  const decoder = new TextDecoder();
-
-  const res = await requestOpenai(req);
-
-  const contentType = res.headers.get("Content-Type") ?? "";
-  if (!contentType.includes("stream")) {
-    const content = await (
-      await res.text()
-    ).replace(/provided:.*. You/, "provided: ***. You");
-    console.log("[Stream] error ", content);
-    return "```json\n" + content + "```";
-  }
-
-  const stream = new ReadableStream({
-    async start(controller) {
-      function onParse(event: any) {
-        if (event.type === "event") {
-          const data = event.data;
-          // https://beta.openai.com/docs/api-reference/completions/create#completions/create-stream
-          if (data === "[DONE]") {
-            controller.close();
-            return;
-          }
-          try {
-            const json = JSON.parse(data);
-            const text = json.choices[0].delta.content;
-            const queue = encoder.encode(text);
-            controller.enqueue(queue);
-          } catch (e) {
-            controller.error(e);
-          }
-        }
-      }
-
-      const parser = createParser(onParse);
-      for await (const chunk of res.body as any) {
-        parser.feed(decoder.decode(chunk, { stream: true }));
-      }
-    },
-  });
-  return stream;
-}
-
-export async function POST(req: NextRequest) {
-  try {
-    const stream = await createStream(req);
-    return new Response(stream);
-  } catch (error) {
-    console.error("[Chat Stream]", error);
-    return new Response(
-      ["```json\n", JSON.stringify(error, null, "  "), "\n```"].join(""),
-    );
-  }
-}
-
-export const runtime = "edge";

app/api/openai/route.ts

@@ -1,24 +1,82 @@
+import { createParser } from "eventsource-parser";
 import { NextRequest, NextResponse } from "next/server";
 import { requestOpenai } from "../common";
 
+async function createStream(res: Response) {
+  const encoder = new TextEncoder();
+  const decoder = new TextDecoder();
+
+  const stream = new ReadableStream({
+    async start(controller) {
+      function onParse(event: any) {
+        if (event.type === "event") {
+          const data = event.data;
+          // https://beta.openai.com/docs/api-reference/completions/create#completions/create-stream
+          if (data === "[DONE]") {
+            controller.close();
+            return;
+          }
+          try {
+            const json = JSON.parse(data);
+            const text = json.choices[0].delta.content;
+            const queue = encoder.encode(text);
+            controller.enqueue(queue);
+          } catch (e) {
+            controller.error(e);
+          }
+        }
+      }
+
+      const parser = createParser(onParse);
+      for await (const chunk of res.body as any) {
+        parser.feed(decoder.decode(chunk, { stream: true }));
+      }
+    },
+  });
+  return stream;
+}
+
+function formatResponse(msg: any) {
+  const jsonMsg = ["```json\n", JSON.stringify(msg, null, "  "), "\n```"].join(
+    "",
+  );
+  return new Response(jsonMsg);
+}
+
 async function makeRequest(req: NextRequest) {
   try {
     const api = await requestOpenai(req);
-    const res = new NextResponse(api.body);
-    res.headers.set("Content-Type", "application/json");
-    res.headers.set("Cache-Control", "no-cache");
-    return res;
+
+    const contentType = api.headers.get("Content-Type") ?? "";
+
+    // streaming response
+    if (contentType.includes("stream")) {
+      const stream = await createStream(api);
+      return new Response(stream);
+    }
+
+    // try to parse error msg
+    try {
+      const mayBeErrorBody = await api.json();
+      if (mayBeErrorBody.error) {
+        console.error("[OpenAI Response] ", mayBeErrorBody);
+        return formatResponse(mayBeErrorBody);
+      } else {
+        const res = new Response(JSON.stringify(mayBeErrorBody));
+        res.headers.set("Content-Type", "application/json");
+        res.headers.set("Cache-Control", "no-cache");
+        return res;
+      }
+    } catch (e) {
+      console.error("[OpenAI Parse] ", e);
+      return formatResponse({
+        msg: "invalid response from openai server",
+        error: e,
+      });
+    }
   } catch (e) {
-    console.error("[OpenAI] ", req.body, e);
-    return NextResponse.json(
-      {
-        error: true,
-        msg: JSON.stringify(e),
-      },
-      {
-        status: 500,
-      },
-    );
+    console.error("[OpenAI] ", e);
+    return formatResponse(e);
   }
 }
 

app/requests.ts

@@ -161,7 +161,7 @@ export async function requestChatStream(
   const reqTimeoutId = setTimeout(() => controller.abort(), TIME_OUT_MS);
 
   try {
-    const res = await fetch("/api/chat-stream", {
+    const res = await fetch("/api/openai", {
       method: "POST",
       headers: {
         "Content-Type": "application/json",

middleware.ts

@@ -3,7 +3,7 @@ import { getServerSideConfig } from "./app/config/server";
 import md5 from "spark-md5";
 
 export const config = {
-  matcher: ["/api/openai", "/api/chat-stream"],
+  matcher: ["/api/openai"],
 };
 
 const serverConfig = getServerSideConfig();