Parsing the severity of the log lines

client/driver/syslog/collector.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"io"
 	"log"
+	s1 "log/syslog"
 	"net"
 	"path/filepath"
 
@@ -97,21 +98,35 @@ func (s *SyslogCollector) LaunchCollector(ctx *LogCollectorContext) (*SyslogColl
 	if err := s.server.Boot(); err != nil {
 		return nil, err
 	}
-	r, w := io.Pipe()
 	logFileSize := int64(ctx.LogConfig.MaxFileSizeMB * 1024 * 1024)
+
+	ro, wo := io.Pipe()
 	lro, err := logrotator.NewLogRotator(filepath.Join(s.taskDir, allocdir.TaskLocal),
 		fmt.Sprintf("%v.stdout", ctx.TaskName), ctx.LogConfig.MaxFiles,
 		logFileSize, s.logger)
 	if err != nil {
 		return nil, err
 	}
-	go lro.Start(r)
+	go lro.Start(ro)
+
+	re, we := io.Pipe()
+	lre, err := logrotator.NewLogRotator(filepath.Join(s.taskDir, allocdir.TaskLocal),
+		fmt.Sprintf("%v.stderr", ctx.TaskName), ctx.LogConfig.MaxFiles,
+		logFileSize, s.logger)
+	if err != nil {
+		return nil, err
+	}
+	go lre.Start(re)
 
-	// map[string]interface{}
 	go func(channel syslog.LogPartsChannel) {
 		for logParts := range channel {
-			w.Write(logParts["content"].([]byte))
-			w.Write([]byte("\n"))
+			s := logParts["severity"].(s1.Priority)
+			if s == s1.LOG_ERR {
+				we.Write(logParts["content"].([]byte))
+			} else {
+				wo.Write(logParts["content"].([]byte))
+			}
+			wo.Write([]byte("\n"))
 		}
 	}(channel)
 	go s.server.Wait()

client/driver/syslog/parser.go

@@ -2,12 +2,35 @@ package syslog
 
 import (
 	"bufio"
+	"fmt"
 	"log"
+	"log/syslog"
+	"strconv"
 	"time"
 
 	"github.com/jeromer/syslogparser"
 )
 
+var (
+	ErrPriorityNoStart  = fmt.Errorf("No start char found for priority")
+	ErrPriorityEmpty    = fmt.Errorf("Priority field empty")
+	ErrPriorityNoEnd    = fmt.Errorf("No end char found for priority")
+	ErrPriorityTooShort = fmt.Errorf("Priority field too short")
+	ErrPriorityTooLong  = fmt.Errorf("Priority field too long")
+	ErrPriorityNonDigit = fmt.Errorf("Non digit found in priority")
+)
+
+const (
+	PRI_PART_START = '<'
+	PRI_PART_END   = '>'
+)
+
+type Priority struct {
+	P syslog.Priority
+	F syslog.Priority
+	S syslog.Priority
+}
+
 type DockerLogParser struct {
 	line []byte
 
@@ -23,8 +46,61 @@ func (d *DockerLogParser) Parse() error {
 }
 
 func (d *DockerLogParser) Dump() syslogparser.LogParts {
+	severity, idx, _ := d.parsePriority(d.line)
 	return map[string]interface{}{
-		"content": d.line,
+		"content":  d.line[idx:],
+		"severity": severity.S,
+	}
+}
+
+func (d *DockerLogParser) parsePriority(line []byte) (Priority, int, error) {
+	cursor := 0
+	pri := d.newPriority(0)
+	if len(line) <= 0 {
+		return pri, cursor, ErrPriorityEmpty
+	}
+	if line[cursor] != PRI_PART_START {
+		return pri, cursor, ErrPriorityNoStart
+	}
+	i := 1
+	priDigit := 0
+	for i < len(line) {
+		if i >= 5 {
+			return pri, cursor, ErrPriorityTooLong
+		}
+		c := line[i]
+		if c == PRI_PART_END {
+			if i == 1 {
+				return pri, cursor, ErrPriorityTooShort
+			}
+			cursor = i + 1
+			return d.newPriority(priDigit), cursor, nil
+		}
+		if d.isDigit(c) {
+			v, e := strconv.Atoi(string(c))
+			if e != nil {
+				return pri, cursor, e
+			}
+			priDigit = (priDigit * 10) + v
+		} else {
+			return pri, cursor, ErrPriorityNonDigit
+		}
+		i++
+	}
+	return pri, cursor, ErrPriorityNoEnd
+}
+
+func (d *DockerLogParser) isDigit(c byte) bool {
+	return c >= '0' && c <= '9'
+}
+
+func (d *DockerLogParser) newPriority(p int) Priority {
+	// The Priority value is calculated by first multiplying the Facility
+	// number by 8 and then adding the numerical value of the Severity.
+	return Priority{
+		P: syslog.Priority(p),
+		F: syslog.Priority(p / 8),
+		S: syslog.Priority(p % 8),
 	}
 }
 

client/driver/syslog/parser_test.go

@@ -0,0 +1,18 @@
+package syslog
+
+import (
+	"log/syslog"
+	"testing"
+)
+
+func TestLogParser_Priority(t *testing.T) {
+	line := []byte("<30>2016-02-10T10:16:43-08:00 d-thinkpad docker/e2a1e3ebd3a3[22950]: 1:C 10 Feb 18:16:43.391 # Warning: no config file specified, using the default config. In order to specify a config file use redis-server /path/to/redis.conf")
+	d := NewDockerLogParser(line)
+	p, err := d.parsePriority(line)
+	if err != nil {
+		t.Fatalf("got an err: %v", err)
+	}
+	if p.S != syslog.LOG_INFO {
+		t.Fatalf("expected serverity: %v, got: %v", syslog.LOG_INFO, p.S)
+	}
+}