added silly tar-generating http server

cmd/trashsrv/main.go

@@ -0,0 +1,109 @@
+package main
+
+import (
+	"archive/tar"
+	"flag"
+	"fmt"
+	"io"
+	"log"
+	"net/http"
+	"os"
+	"path/filepath"
+	"strconv"
+	"time"
+
+	"mcquay.me/trash"
+)
+
+func init() {
+	log.SetFlags(log.Lshortfile)
+}
+
+type fake struct {
+	name string
+	size int64
+}
+
+func (f fake) Name() string {
+	return f.name
+}
+
+func (f fake) Size() int64 {
+	return f.size
+}
+
+func (f fake) Mode() os.FileMode {
+	return 0644
+}
+
+func (f fake) ModTime() time.Time {
+	return time.Now()
+}
+
+func (f fake) IsDir() bool {
+	return false
+}
+
+func (f fake) Sys() interface{} {
+	return nil
+}
+
+func tarball(w http.ResponseWriter, req *http.Request) {
+	if err := req.ParseForm(); err != nil {
+		http.Error(w, fmt.Sprintf("error parsing form: %v", err), http.StatusBadRequest)
+		return
+	}
+
+	size, ok := req.Form["size"]
+	if !ok {
+		http.Error(w, "must provide size parameter", http.StatusBadRequest)
+		return
+	}
+	if len(size) != 1 {
+		http.Error(w, fmt.Sprintf("only specify one size (%d specified)", len(size)), http.StatusBadRequest)
+		return
+	}
+	sz, err := strconv.ParseFloat(size[0], 64)
+	if err != nil {
+		http.Error(w, fmt.Sprintf("error parsing size: %v", err), http.StatusBadRequest)
+		return
+	}
+	sz = sz * 1024 * 1024 * 1024
+	_, name := filepath.Split(req.URL.Path)
+	if name == "" {
+		name = "file.tar"
+	}
+	w.Header().Set("Content-Disposition", fmt.Sprintf("inline; filename=%q", name))
+	w.Header().Set("content-type", "application/x-tar")
+	lr := io.LimitReader(trash.Reader, int64(sz))
+	t := tar.NewWriter(w)
+	hdr, err := tar.FileInfoHeader(fake{"foo", int64(sz)}, "")
+	if err != nil {
+		http.Error(w, fmt.Sprintf("error creating tar header: %v", err), http.StatusBadRequest)
+		return
+	}
+	hdr.Name = "trash.dat"
+	if err := t.WriteHeader(hdr); err != nil {
+		http.Error(w, fmt.Sprintf("error writing tar header: %v", err), http.StatusBadRequest)
+		return
+	}
+	if _, err := io.Copy(t, lr); err != nil {
+		log.Printf("problem writing tar to http body: %v", err)
+		return
+	}
+	if err := t.Close(); err != nil {
+		log.Printf("problem closing tar: %v", err)
+		return
+	}
+}
+
+var port = flag.Int64("-port", 9292, "port")
+
+func main() {
+	flag.Parse()
+	http.HandleFunc("/", tarball)
+	if err := http.ListenAndServe(fmt.Sprintf(":%d", *port), nil); err != nil {
+		fmt.Fprintf(os.Stderr, "%v", err)
+		os.Exit(1)
+	}
+}