Merge pull request #55 from cloudflare/transport-fix

Fix transport package

transport/file.go

@@ -1,6 +1,7 @@
 package transport
 
 import (
+	"io"
 	"os"
 
 	log "github.com/Sirupsen/logrus"
@@ -8,9 +9,20 @@ import (
 
 type fileReader struct {
 	filename string
+	fd       *os.File
 }
 
-func newFileReader(filname string) (*os.File, error) {
+func (fr *fileReader) Read(b []byte) (n int, err error) {
+	return fr.fd.Read(b)
+}
+
+func (fr *fileReader) Close() error {
+	return fr.fd.Close()
+}
+
+func newFileReader(filname string) (io.ReadCloser, error) {
 	log.Infof("Reading file '%s'", filname)
-	return os.Open(filname)
+	fd, err := os.Open(filname)
+	fr := fileReader{filename: filname, fd: fd}
+	return &fr, err
 }

transport/http.go

@@ -15,7 +15,7 @@ type httpReader struct {
 	Timeout time.Duration
 }
 
-func newHTTPReader(url string, timeout time.Duration) (*io.ReadCloser, error) {
+func newHTTPReader(url string, timeout time.Duration) (io.ReadCloser, error) {
 	hr := httpReader{URL: url, Timeout: timeout}
 
 	log.Infof("GET %s timeout=%s", hr.URL, hr.Timeout)
@@ -38,8 +38,6 @@ func newHTTPReader(url string, timeout time.Duration) (*io.ReadCloser, error) {
 		return nil, fmt.Errorf("Request to Alertmanager failed with %s", resp.Status)
 	}
 
-	defer resp.Body.Close()
-
 	var reader io.ReadCloser
 	switch resp.Header.Get("Content-Encoding") {
 	case "gzip":
@@ -47,9 +45,8 @@ func newHTTPReader(url string, timeout time.Duration) (*io.ReadCloser, error) {
 		if err != nil {
 			return nil, fmt.Errorf("Failed to decode gzipped content: %s", err.Error())
 		}
-		defer reader.Close()
 	default:
 		reader = resp.Body
 	}
-	return &reader, nil
+	return reader, nil
 }

transport/transport.go

@@ -3,37 +3,29 @@ package transport
 import (
 	"encoding/json"
 	"fmt"
+	"io"
 	"net/url"
 	"time"
 )
 
-func readFile(filename string, target interface{}) error {
-	reader, err := newFileReader(filename)
-	if err != nil {
-		return err
-	}
-	return json.NewDecoder(reader).Decode(target)
-}
-
-func readHTTP(url string, timeout time.Duration, target interface{}) error {
-	reader, err := newHTTPReader(url, timeout)
-	if err != nil {
-		return err
-	}
-	return json.NewDecoder(*reader).Decode(target)
-}
-
 // ReadJSON using one of supported transports (file:// http://)
 func ReadJSON(uri string, timeout time.Duration, target interface{}) error {
 	u, err := url.Parse(uri)
 	if err != nil {
 		return err
 	}
-	if u.Scheme == "file" {
-		return readFile(u.Path, target)
+	var reader io.ReadCloser
+	switch u.Scheme {
+	case "http", "https":
+		reader, err = newHTTPReader(u.String(), timeout)
+	case "file":
+		reader, err = newFileReader(u.Path)
+	default:
+		return fmt.Errorf("Unsupported URI scheme '%s' in '%s'", u.Scheme, u)
 	}
-	if u.Scheme == "http" || u.Scheme == "https" {
-		return readHTTP(u.String(), timeout, target)
+	if err != nil {
+		return err
 	}
-	return fmt.Errorf("Unsupported URI scheme '%s' in '%s'", u.Scheme, u)
+	defer reader.Close()
+	return json.NewDecoder(reader).Decode(target)
 }