Merge pull request #1 from campoy/master

code review

Author: thesandlord

logpipe.go

@@ -1,24 +1,23 @@
-/*
-	Copyright 2017, Google, Inc.
- Licensed under the Apache License, Version 2.0 (the "License");
- you may not use this file except in compliance with the License.
- You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
- Unless required by applicable law or agreed to in writing, software
- distributed under the License is distributed on an "AS IS" BASIS,
- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- See the License for the specific language governing permissions and
- limitations under the License.
-*/
+// 	Copyright 2017, Google, Inc.
+//  Licensed under the Apache License, Version 2.0 (the "License");
+//  you may not use this file except in compliance with the License.
+//  You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+//  Unless required by applicable law or agreed to in writing, software
+//  distributed under the License is distributed on an "AS IS" BASIS,
+//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+//  See the License for the specific language governing permissions and
+//  limitations under the License.
 
 // Command logpipe is a service that will let you pipe logs directly to Stackdriver Logging.
 package main
 
 import (
 	"bufio"
 	"fmt"
+	"io"
 	"log"
 	"os"
 
@@ -29,51 +28,38 @@ import (
 )
 
 func main() {
-	ctx := context.Background()
-
 	var opts struct {
 		ProjectID string `short:"p" long:"project" description:"Google Cloud Platform Project ID" required:"true"`
 		LogName   string `short:"l" long:"logname" description:"The name of the log to write to" default:"default"`
 	}
-
-	flags.Parse(&opts)
-
-	projectID := &opts.ProjectID
-	logName := &opts.LogName
-
-	if *projectID == "" {
-		fmt.Printf("Please specify a project ID\n")
-		return
+	if _, err := flags.Parse(&opts); err != nil {
+		os.Exit(2)
 	}
 
 	// Check if Standard In is coming from a pipe
 	fi, err := os.Stdin.Stat()
 	if err != nil {
-		panic(err)
+		log.Fatalf("Could not stat standard input: %v", err)
 	}
 	if fi.Mode()&os.ModeNamedPipe == 0 {
-		fmt.Printf("Nothing is piped in so there is nothing to log!\n")
-		return
+		fmt.Fprintln(os.Stderr, "Nothing is piped in so there is nothing to log!")
+		os.Exit(2)
 	}
 
 	// Creates a client.
-	client, err := logging.NewClient(ctx, *projectID)
+	ctx := context.Background()
+	client, err := logging.NewClient(ctx, opts.ProjectID)
 	if err != nil {
 		log.Fatalf("Failed to create client: %v", err)
 	}
 
 	// Selects the log to write to.
-	logger := client.Logger(*logName)
+	logger := client.Logger(opts.LogName)
 
 	// Read from Stdin and log it to Stdout and Stackdriver
-	scanner := bufio.NewScanner(os.Stdin)
-	for scanner.Scan() {
-		text := scanner.Text()
-		fmt.Println(text)
-		logger.Log(logging.Entry{Payload: text})
-	}
-	if err := scanner.Err(); err != nil {
-		log.Fatalf("Failed to scan input: %v", err)
+	s := bufio.NewScanner(io.TeeReader(os.Stdin, os.Stdout))
+	for s.Scan() {
+		logger.Log(logging.Entry{Payload: s.Text()})
 	}
 
 	// Closes the client and flushes the buffer to the Stackdriver Logging
@@ -82,5 +68,9 @@ func main() {
 		log.Fatalf("Failed to close client: %v", err)
 	}
 
-	fmt.Printf("Finished logging\n")
+	if err := s.Err(); err != nil {
+		log.Fatalf("Failed to scan input: %v", err)
+	}
+
+	log.Println("Finished logging")
 }