docker fix

ai-chat-backend/Dockerfile

@@ -1,19 +1,41 @@
 # 编译阶段
-FROM golang:1.24 AS stage0
-RUN go env -w GOPROXY=https://proxy.golang.com.cn,https://goproxy.cn,direct
-ADD ./ /src/ai-chat-backend
-WORKDIR /src/ai-chat-backend
-RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -o ai-chat-backend cmd/*.go
+FROM golang:1.24 AS builder
 
-FROM alpine:3.18 AS stage1
-ADD ./curl-amd64 /usr/bin/curl
+ENV CGO_ENABLED=0 \
+    GOOS=linux \
+    GOARCH=amd64 \
+    GOPROXY=https://goproxy.cn|https://proxy.golang.google.cn|direct \
+    GOSUMDB=sum.golang.google.cn
+
+WORKDIR /src/ai-chat-backend
+
+# 先复制依赖描述文件，最大化利用缓存
+COPY go.mod go.sum ./
+
+RUN --mount=type=cache,target=/go/pkg/mod \
+    --mount=type=cache,target=/root/.cache/go-build \
+    go mod download -x
+
+# 再复制源码
+COPY . .
+
+RUN --mount=type=cache,target=/go/pkg/mod \
+    --mount=type=cache,target=/root/.cache/go-build \
+    go build -trimpath -ldflags="-s -w" -o /out/ai-chat-backend ./cmd
+
+# 运行阶段
+FROM alpine:3.18 AS runtime
+
+COPY ./curl-amd64 /usr/bin/curl
 RUN chmod +x /usr/bin/curl
+
 LABEL maintainer="nick"
+
 WORKDIR /app/
-ADD ./dev.config.yaml /app/config.yaml
-ADD ./www /app/www
-COPY --from=stage0 /src/ai-chat-backend/ai-chat-backend ./
-# 指定入口程序
+
+COPY ./dev.config.yaml /app/config.yaml
+COPY ./www /app/www
+COPY --from=builder /out/ai-chat-backend ./ai-chat-backend
+
 ENTRYPOINT ["./ai-chat-backend"]
-# 指定容器的启动命令或者入口程序的参数
-CMD ["--config=config.yaml"]
+CMD ["--config=config.yaml"]