init ai backend

backend/src/main/java/com/zl/mjga/controller/AiController.java

@@ -0,0 +1,41 @@
+package com.zl.mjga.controller;
+
+import com.zl.mjga.service.DeepSeekAiService;
+import dev.langchain4j.service.TokenStream;
+import java.time.Duration;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.http.MediaType;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Sinks;
+
+@RestController
+@RequestMapping("/ai")
+@RequiredArgsConstructor
+@Slf4j
+public class AiController {
+
+  private final DeepSeekAiService deepSeekAiService;
+
+  @PostMapping(value = "/chat", produces = MediaType.TEXT_EVENT_STREAM_VALUE)
+  public Flux<String> chat(@RequestBody String userMessage) {
+    Sinks.Many<String> sink = Sinks.many().unicast().onBackpressureBuffer();
+    TokenStream chat = deepSeekAiService.chat("123", userMessage);
+    chat.onPartialResponse(sink::tryEmitNext)
+        .onCompleteResponse(
+            r -> {
+              sink.tryEmitNext("[DONE]");
+              sink.tryEmitComplete();
+            })
+        .onError(sink::tryEmitError)
+        .start();
+
+    return sink.asFlux()
+        .timeout(Duration.ofSeconds(60))
+        .onErrorResume(e -> Flux.just("Timeout occurred"));
+  }
+}