replace zxq.co/ripple/hanayo

vendor/github.com/valyala/fasthttp/expvarhandler/expvar.go

@@ -0,0 +1,62 @@
+// Package expvarhandler provides fasthttp-compatible request handler
+// serving expvars.
+package expvarhandler
+
+import (
+	"expvar"
+	"fmt"
+	"regexp"
+
+	"github.com/valyala/fasthttp"
+)
+
+var (
+	expvarHandlerCalls = expvar.NewInt("expvarHandlerCalls")
+	expvarRegexpErrors = expvar.NewInt("expvarRegexpErrors")
+)
+
+// ExpvarHandler dumps json representation of expvars to http response.
+//
+// Expvars may be filtered by regexp provided via 'r' query argument.
+//
+// See https://golang.org/pkg/expvar/ for details.
+func ExpvarHandler(ctx *fasthttp.RequestCtx) {
+	expvarHandlerCalls.Add(1)
+
+	ctx.Response.Reset()
+
+	r, err := getExpvarRegexp(ctx)
+	if err != nil {
+		expvarRegexpErrors.Add(1)
+		fmt.Fprintf(ctx, "Error when obtaining expvar regexp: %s", err)
+		ctx.SetStatusCode(fasthttp.StatusBadRequest)
+		return
+	}
+
+	fmt.Fprintf(ctx, "{\n")
+	first := true
+	expvar.Do(func(kv expvar.KeyValue) {
+		if !first {
+			fmt.Fprintf(ctx, ",\n")
+		}
+		if r.MatchString(kv.Key) {
+			first = false
+			fmt.Fprintf(ctx, "\t%q: %s", kv.Key, kv.Value)
+		}
+	})
+	fmt.Fprintf(ctx, "\n}\n")
+
+	ctx.SetContentType("application/json; charset=utf-8")
+}
+
+func getExpvarRegexp(ctx *fasthttp.RequestCtx) (*regexp.Regexp, error) {
+	r := string(ctx.QueryArgs().Peek("r"))
+	if len(r) == 0 {
+		r = "."
+	}
+	rr, err := regexp.Compile(r)
+	if err != nil {
+		return nil, fmt.Errorf("cannot parse r=%q: %s", r, err)
+	}
+	return rr, nil
+}