From 159c06de8bd912553ec9dc7c8ec2e8574c6bd62a Mon Sep 17 00:00:00 2001
From: Rodolfo Carvalho <rhcarvalho@gmail.com>
Date: Thu, 23 Jul 2015 23:01:48 +0200
Subject: [PATCH] Include list of recent builds in error message

Fixes #3359
---
 pkg/build/api/sort.go        | 17 +++++++++++
 pkg/build/api/sort_test.go   | 33 +++++++++++++++++++++
 pkg/cmd/cli/cmd/buildlogs.go | 56 +++++++++++++++++++++++++++++++++++-
 3 files changed, 105 insertions(+), 1 deletion(-)
 create mode 100644 pkg/build/api/sort.go
 create mode 100644 pkg/build/api/sort_test.go

diff --git a/pkg/build/api/sort.go b/pkg/build/api/sort.go
new file mode 100644
index 000000000000..8d7107875079
--- /dev/null
+++ b/pkg/build/api/sort.go
@@ -0,0 +1,17 @@
+package api
+
+// ByCreationTimestamp implements sort.Interface for []Build based on the
+// CreationTimestamp field.
+type ByCreationTimestamp []Build
+
+func (b ByCreationTimestamp) Len() int {
+	return len(b)
+}
+
+func (b ByCreationTimestamp) Less(i, j int) bool {
+	return b[i].CreationTimestamp.Before(b[j].CreationTimestamp)
+}
+
+func (b ByCreationTimestamp) Swap(i, j int) {
+	b[i], b[j] = b[j], b[i]
+}
diff --git a/pkg/build/api/sort_test.go b/pkg/build/api/sort_test.go
new file mode 100644
index 000000000000..61b7724c258e
--- /dev/null
+++ b/pkg/build/api/sort_test.go
@@ -0,0 +1,33 @@
+package api
+
+import (
+	"sort"
+	"testing"
+	"time"
+
+	kapi "github.com/GoogleCloudPlatform/kubernetes/pkg/api"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/util"
+)
+
+func TestSortByCreationTimestamp(t *testing.T) {
+	present := util.Now()
+	past := util.NewTime(present.Add(-time.Minute))
+	builds := []Build{
+		{
+			ObjectMeta: kapi.ObjectMeta{
+				Name:              "present",
+				CreationTimestamp: present,
+			},
+		},
+		{
+			ObjectMeta: kapi.ObjectMeta{
+				Name:              "past",
+				CreationTimestamp: past,
+			},
+		},
+	}
+	sort.Sort(ByCreationTimestamp(builds))
+	if [2]string{builds[0].Name, builds[1].Name} != [2]string{"past", "present"} {
+		t.Errorf("Unexpected sort order")
+	}
+}
diff --git a/pkg/cmd/cli/cmd/buildlogs.go b/pkg/cmd/cli/cmd/buildlogs.go
index 61d1dafb6b5d..9ff2093188ec 100644
--- a/pkg/cmd/cli/cmd/buildlogs.go
+++ b/pkg/cmd/cli/cmd/buildlogs.go
@@ -4,12 +4,17 @@ import (
 	"fmt"
 	"io"
 	"os"
+	"sort"
 	"strings"
+	"time"
 
+	"github.com/docker/docker/pkg/units"
 	"github.com/spf13/cobra"
 
 	kclient "github.com/GoogleCloudPlatform/kubernetes/pkg/client"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/fields"
 	cmdutil "github.com/GoogleCloudPlatform/kubernetes/pkg/kubectl/cmd/util"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/labels"
 
 	"github.com/openshift/origin/pkg/build/api"
 	buildutil "github.com/openshift/origin/pkg/build/util"
@@ -56,7 +61,37 @@ func NewCmdBuildLogs(fullName string, f *clientcmd.Factory, out io.Writer) *cobr
 // RunBuildLogs contains all the necessary functionality for the OpenShift cli build-logs command
 func RunBuildLogs(f *clientcmd.Factory, out io.Writer, cmd *cobra.Command, opts api.BuildLogOptions, args []string) error {
 	if len(args) != 1 {
-		return cmdutil.UsageError(cmd, "A build name is required")
+		// maximum time to wait for a list of builds
+		timeout := 800 * time.Millisecond
+		// maximum number of builds to list
+		maxBuildListLen := 10
+		ch := make(chan error)
+		go func() {
+			// TODO fetch via API no more than maxBuildListLen builds
+			builds, err := getBuilds(f)
+			if err != nil {
+				return
+			}
+			if len(builds) == 0 {
+				ch <- cmdutil.UsageError(cmd, "There are no builds in the current project")
+				return
+			}
+			sort.Sort(sort.Reverse(api.ByCreationTimestamp(builds)))
+			msg := "A build name is required. Most recent builds:"
+			for i, b := range builds {
+				if i == maxBuildListLen {
+					break
+				}
+				msg += fmt.Sprintf("\n* %s\t%s\t%s ago", b.Name, b.Status.Phase, units.HumanDuration(time.Since(b.CreationTimestamp.Time)))
+			}
+			ch <- cmdutil.UsageError(cmd, msg)
+		}()
+		select {
+		case <-time.After(timeout):
+			return cmdutil.UsageError(cmd, "A build name is required")
+		case err := <-ch:
+			return err
+		}
 	}
 
 	namespace, _, err := f.DefaultNamespace()
@@ -78,3 +113,22 @@ func RunBuildLogs(f *clientcmd.Factory, out io.Writer, cmd *cobra.Command, opts
 	_, err = io.Copy(out, readCloser)
 	return err
 }
+
+func getBuilds(f *clientcmd.Factory) ([]api.Build, error) {
+	namespace, _, err := f.DefaultNamespace()
+	if err != nil {
+		return nil, err
+	}
+
+	c, _, err := f.Clients()
+	if err != nil {
+		return nil, err
+	}
+
+	b, err := c.Builds(namespace).List(labels.Everything(), fields.Everything())
+	if err != nil {
+		return nil, err
+	}
+
+	return b.Items, nil
+}