add drone build logs cmd

Signed-off-by: Vasiliy Tolstov <v.tolstov@selfip.ru>

drone/build.go

@@ -8,6 +8,7 @@ var buildCmd = cli.Command{
 	Subcommands: []cli.Command{
 		buildListCmd,
 		buildLastCmd,
+		buildLogsCmd,
 		buildInfoCmd,
 		buildStopCmd,
 		buildStartCmd,

drone/build_logs.go

@@ -0,0 +1,84 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"strconv"
+
+	"github.com/codegangsta/cli"
+	"github.com/drone/drone/build"
+)
+
+var buildLogsCmd = cli.Command{
+	Name:  "logs",
+	Usage: "show build logs",
+	Action: func(c *cli.Context) {
+		if err := buildLogs(c); err != nil {
+			log.Fatalln(err)
+		}
+	},
+}
+
+func buildLogs(c *cli.Context) error {
+	repo := c.Args().First()
+	owner, name, err := parseRepo(repo)
+	if err != nil {
+		return err
+	}
+
+	client, err := newClient(c)
+	if err != nil {
+		return err
+	}
+
+	buildArg := c.Args().Get(1)
+	var number int
+	if buildArg == "last" {
+		// Fetch the build number from the last build
+		build, err := client.BuildLast(owner, name, "")
+		if err != nil {
+			return err
+		}
+		number = build.Number
+	} else {
+		number, err = strconv.Atoi(buildArg)
+		if err != nil {
+			return err
+		}
+	}
+
+	job, _ := strconv.Atoi(c.Args().Get(2))
+	if job == 0 {
+		job = 1
+	}
+
+	r, err := client.BuildLogs(owner, name, number, job)
+	if err != nil {
+		return err
+	}
+	defer r.Close()
+
+	dec := json.NewDecoder(r)
+	fmt.Printf("Logs for build %s/%s#%d.%d\n", owner, name, number, job)
+	var line build.Line
+
+	_, err = dec.Token()
+	if err != nil {
+		return err
+	}
+
+	for dec.More() {
+		if err = dec.Decode(&line); err != nil {
+			return err
+		}
+		fmt.Printf("%s\n", line.Out)
+	}
+
+	_, err = dec.Token()
+	if err != nil {
+		return err
+	}
+
+	return nil
+}