优化

go/controllers/backend_weather.go

@@ -0,0 +1,146 @@
+package controllers
+
+import (
+	"bytes"
+	"encoding/json"
+	"io"
+	"net/http"
+	"strconv"
+	"strings"
+	"time"
+
+	beego "github.com/beego/beego/v2/server/web"
+)
+
+// BackendWeatherController 天气实时数据代理。
+//
+// 数据源：中国天气网 d1.weather.com.cn（国内真实数据）。
+// 该接口有防盗链，浏览器直连会被 Referer 校验拦掉、也会跨域，
+// 因此由服务端带 Referer 抓取后统一返回 JSON。
+type BackendWeatherController struct {
+	beego.Controller
+}
+
+// 常用城市编码（中国天气网 citycode），未命中时按入参 code 直取
+var weatherCityCodes = map[string]string{
+	"连云港": "101191001",
+	"南京":  "101190101",
+	"苏州":  "101190401",
+	"无锡":  "101190201",
+	"常州":  "101191101",
+	"南通":  "101190501",
+	"扬州":  "101190601",
+	"徐州":  "101190801",
+	"盐城":  "101190701",
+	"淮安":  "101190901",
+	"镇江":  "101190301",
+	"泰州":  "101191201",
+	"宿迁":  "101191301",
+	"北京":  "101010100",
+	"上海":  "101020100",
+	"广州":  "101280101",
+	"深圳":  "101280601",
+	"杭州":  "101210101",
+}
+
+const defaultWeatherCity = "连云港"
+
+// Now GET /backend/weather/now?city=连云港 或 ?code=101191201
+func (c *BackendWeatherController) Now() {
+	city := strings.TrimSpace(c.GetString("city"))
+	code := strings.TrimSpace(c.GetString("code"))
+	if code == "" {
+		code = weatherCityCodes[city]
+	}
+	if code == "" {
+		code = weatherCityCodes[defaultWeatherCity]
+		city = defaultWeatherCity
+	}
+
+	client := &http.Client{Timeout: 8 * time.Second}
+	ts := strconv.FormatInt(time.Now().UnixMilli(), 10)
+	referer := "https://www.weather.com.cn/weather1d/" + code + ".shtml"
+
+	// 主数据源：dingzhi（含天气现象 + 气温）。中国天气网已拒绝 http 明文连接，必须走 https。
+	info := weatherFetchJSON(client, "https://d1.weather.com.cn/dingzhi/"+code+".html?_="+ts, referer)
+	if wi, ok := info["weatherinfo"].(map[string]interface{}); ok {
+		info = wi
+	}
+	// 兜底：sk_2d（实况气温，无天气现象）
+	if len(info) == 0 {
+		info = weatherFetchJSON(client, "https://d1.weather.com.cn/sk_2d/"+code+".html?_="+ts, referer)
+	}
+
+	if len(info) == 0 {
+		c.Ctx.Output.SetStatus(http.StatusBadGateway)
+		c.Data["json"] = map[string]interface{}{"code": 502, "msg": "天气数据获取失败，请稍后重试"}
+		_ = c.ServeJSON()
+		return
+	}
+
+	cityName := weatherStr(info, "cityname", "city", "name")
+	if cityName == "" {
+		cityName = city
+	}
+	temp := strings.TrimSuffix(weatherStr(info, "temp", "real"), "℃")
+	text := weatherStr(info, "weather", "weather1")
+
+	c.Data["json"] = map[string]interface{}{
+		"code": 200,
+		"msg":  "ok",
+		"data": map[string]interface{}{
+			"city":   cityName,
+			"temp":   temp,
+			"text":   text,
+			"update": weatherStr(info, "time", "fctime", "date"),
+			"code":   code,
+		},
+	}
+	_ = c.ServeJSON()
+}
+
+// weatherFetchJSON 带 Referer/UA 抓取中国天气网页面并解析其中的 JSON 对象
+func weatherFetchJSON(client *http.Client, url, referer string) map[string]interface{} {
+	req, err := http.NewRequest(http.MethodGet, url, nil)
+	if err != nil {
+		return nil
+	}
+	req.Header.Set("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36")
+	req.Header.Set("Referer", referer)
+	req.Header.Set("Accept", "*/*")
+
+	resp, err := client.Do(req)
+	if err != nil {
+		return nil
+	}
+	defer resp.Body.Close()
+
+	body, err := io.ReadAll(io.LimitReader(resp.Body, 1<<20))
+	if err != nil {
+		return nil
+	}
+
+	// 返回体形如：var cityDZ101191001 ={"weatherinfo":{...}};var alarmDZ101191001 ={"w":[]}
+	// 从第一个 '{' 起用 json.Decoder 只解出第一个完整对象（正则贪婪匹配会跨越多个对象导致解析失败）
+	idx := bytes.IndexByte(body, '{')
+	if idx < 0 {
+		return nil
+	}
+	var out map[string]interface{}
+	if json.NewDecoder(bytes.NewReader(body[idx:])).Decode(&out) != nil {
+		return nil
+	}
+	return out
+}
+
+// weatherStr 按候选字段顺序取第一个非空字符串值
+func weatherStr(m map[string]interface{}, keys ...string) string {
+	for _, k := range keys {
+		if v, ok := m[k]; ok {
+			if s, ok := v.(string); ok && strings.TrimSpace(s) != "" {
+				return strings.TrimSpace(s)
+			}
+		}
+	}
+	return ""
+}