Cleanup and trimming container list

- Trimmed down the list of containers omitting `k8s-POD` containers
- Found that policy controller is logging to stderr only, fixed up
  gathering of logs to ensure we still get all of it
- Code cleanup

calicoctl/commands/node/diags.go

@@ -23,11 +23,11 @@ import (
 	"strings"
 	"time"
 	"bufio"
-	"bytes"
 
 	"github.com/docopt/docopt-go"
 	log "github.com/sirupsen/logrus"
 	shutil "github.com/termie/go-shutil"
+	"regexp"
 )
 
 // diagCmd is a struct to hold a command, cmd info and filename to run diagnostic on
@@ -165,32 +165,34 @@ func getNodeContainerLogs(logDir string) {
 	os.Mkdir(logDir, os.ModeDir)
 
 	// Get a list of Calico containers running on this Node.
-	var stderr bytes.Buffer
-	cmd := exec.Command("docker", "ps", "-a", "--filter", "\"name=calico\"", "--format", "{{.Names}}: {{.CreatedAt}}")
-	cmd.Stderr = &stderr
-	containers, err := cmd.Output()
+	result, err := exec.Command("docker", "ps", "-a", "--filter", "\"name=calico\"", "--format", "{{.Names}}: {{.CreatedAt}}").CombinedOutput()
 	if err != nil {
-		fmt.Printf("Could not run docker command: %s\n", stderr.String())
+		fmt.Printf("Could not run docker command: %s\n", string(result))
 		return
 	}
 
 	// No Calico containers found.
-	if string(containers) == "" {
+	if string(result) == "" {
 		log.Debug("Did not find any Calico containers")
 		return
 	}
 
+	// Remove any containers that have "k8s_POD" in them.
+	re := regexp.MustCompile("(?m)[\r\n]+^.*k8s_POD.*$")
+	containers := re.ReplaceAllString(string(result), "")
+
 	fmt.Println("Copying logs from Calico containers")
-	err = ioutil.WriteFile(logDir+"/"+"container_creation_time", containers,0666)
+	err = ioutil.WriteFile(logDir+"/"+"container_creation_time", []byte(containers),0666)
 	if err != nil {
 		fmt.Printf("Could not save output of `docker ps` command to container_creation_time: %s\n", err)
 	}
 
 	// Grab the log for each container and write it as <containerName>.log.
-	scanner := bufio.NewScanner(strings.NewReader(string(containers)))
+	scanner := bufio.NewScanner(strings.NewReader(containers))
 	for scanner.Scan() {
 		name := strings.Split(scanner.Text(), ":")[0]
-		cLog, err := exec.Command("docker", "logs", name).Output()
+		log.Debugf("Getting logs for container %s", name)
+		cLog, err := exec.Command("docker", "logs", name).CombinedOutput()
 		if err != nil {
 			fmt.Printf("Could not pull log for container %s: %s\n", name, err)
 			continue
@@ -212,13 +214,9 @@ func writeDiags(cmds diagCmd, dir string) {
 
 	parts := strings.Fields(cmds.cmd)
 
-	var stderr bytes.Buffer
-	cmd := exec.Command(parts[0], parts[1:]...)
-	cmd.Stderr = &stderr
-
-	content, err := cmd.Output()
+	content, err := exec.Command(parts[0], parts[1:]...).CombinedOutput()
 	if err != nil {
-		fmt.Printf("Failed to run command: %s\nError: %s\n", cmds.cmd, stderr.String())
+		fmt.Printf("Failed to run command: %s\nError: %s\n", cmds.cmd, string(content))
 	}
 
 	// This is for the commands we want to run but don't want to save the output