add copyreport utility

useful for codec and report structure experiments

extras/copyreport/Makefile

@@ -0,0 +1,19 @@
+.PHONY: all vet lint build test clean
+
+all: build test vet lint
+
+vet:
+	go vet ./...
+
+lint:
+	golint .
+
+build:
+	go build
+
+test:
+	go test
+
+clean:
+	go clean
+

extras/copyreport/main.go

@@ -0,0 +1,26 @@
+// Copy a report, decoding and re-encoding it.
+package main
+
+import (
+	"compress/gzip"
+	"flag"
+	"log"
+
+	"github.com/weaveworks/scope/report"
+)
+
+func main() {
+	flag.Parse()
+
+	if len(flag.Args()) != 2 {
+		log.Fatal("usage: copyreport src.(json|msgpack)[.gz] dst.(json|msgpack)[.gz]")
+	}
+
+	rpt, err := report.MakeFromFile(flag.Arg(0))
+	if err != nil {
+		log.Fatal(err)
+	}
+	if err = rpt.WriteToFile(flag.Arg(1), gzip.DefaultCompression); err != nil {
+		log.Fatal(err)
+	}
+}