Support relabel path of ehttp client to solve the high cardinality issue

client/ehttp/config.go

@@ -1,6 +1,7 @@
 package ehttp
 
 import (
+	"regexp"
 	"runtime"
 	"time"
 
@@ -21,6 +22,13 @@ type Config struct {
 	EnableKeepAlives           bool          // 是否开启长连接，默认打开
 	EnableAccessInterceptor    bool          // 是否开启记录请求数据，默认不开启
 	EnableAccessInterceptorRes bool          // 是否开启记录响应参数，默认不开启
+	PathRelabel                []Relabel     // path 重命名 (metric 用)
+}
+
+type Relabel struct {
+	Match       string
+	matchReg    *regexp.Regexp
+	Replacement string
 }
 
 // DefaultConfig ...

client/ehttp/container.go

@@ -1,6 +1,8 @@
 package ehttp
 
 import (
+	"regexp"
+
 	"github.com/gotomicro/ego/core/econf"
 	"github.com/gotomicro/ego/core/elog"
 )
@@ -31,6 +33,13 @@ func Load(key string) *Container {
 		c.logger.Panic("parse config error", elog.FieldErr(err), elog.FieldKey(key))
 		return c
 	}
+	for idx, relabel := range c.config.PathRelabel {
+		if reg, err := regexp.Compile(relabel.Match); err == nil {
+			c.config.PathRelabel[idx].matchReg = reg
+		} else {
+			c.logger.Panic("parse path relabel error", elog.FieldErr(err), elog.FieldKey(key))
+		}
+	}
 	c.name = key
 	return c
 }

client/ehttp/interceptor.go

@@ -93,13 +93,27 @@ func beg(ctx context.Context) time.Time {
 func fixedInterceptor(name string, config *Config, logger *elog.Component) (resty.RequestMiddleware, resty.ResponseMiddleware, resty.ErrorHook) {
 	return func(cli *resty.Client, req *resty.Request) error {
 		// 这个URL可能不准，每次请求都需要重复url.Parse()，会增加一定的性能损耗
-		concatURL := strings.TrimRight(config.Addr, "/") + "/" + strings.TrimLeft(req.URL, "/")
+		var concatURL string
+		if config.Addr == "" {
+			// 没有配置addr，host可能在url里面 (request.Get("http://xxx.com/xxx"))
+			concatURL = req.URL
+		} else {
+			concatURL = strings.TrimRight(config.Addr, "/") + "/" + strings.TrimLeft(req.URL, "/")
+		}
 		u, err := url.Parse(concatURL)
 		if err != nil {
 			logger.Warn("invalid url", elog.String("concatURL", concatURL), elog.FieldErr(err))
 			req.SetContext(context.WithValue(context.WithValue(req.Context(), begKey{}, time.Now()), urlKey{}, &url.URL{}))
 			return err
 		}
+		if len(config.PathRelabel) > 0 {
+			for _, relabel := range config.PathRelabel {
+				if relabel.matchReg.MatchString(u.Path) {
+					u.Path = relabel.Replacement
+					break
+				}
+			}
+		}
 		req.SetContext(context.WithValue(context.WithValue(req.Context(), begKey{}, time.Now()), urlKey{}, u))
 		return nil
 	}, nil, nil

client/ehttp/options.go

@@ -85,3 +85,10 @@ func WithEnableAccessInterceptorRes(enableAccessInterceptorRes bool) Option {
 		c.config.EnableAccessInterceptorRes = enableAccessInterceptorRes
 	}
 }
+
+// WithPathRelabel 设置路径重命名
+func WithPathRelabel(match string, replacement string) Option {
+	return func(c *Container) {
+		c.config.PathRelabel = append(c.config.PathRelabel, Relabel{Match: match, Replacement: replacement})
+	}
+}