Allow dos line endings in tail and logparser (#2920)

Parsing dos line ending delimited line protocol is still illegal in most
cases.

plugins/inputs/logparser/logparser.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"log"
 	"reflect"
+	"strings"
 	"sync"
 
 	"github.com/influxdata/tail"
@@ -47,7 +48,7 @@ const sampleConfig = `
   ##   /var/log/*/*.log    -> find all .log files with a parent dir in /var/log
   ##   /var/log/apache.log -> only tail the apache log file
   files = ["/var/log/apache/access.log"]
-  
+
   ## Read files that currently exist from the beginning. Files that are created
   ## while telegraf is running (and that match the "files" globs) will always
   ## be read from the beginning.
@@ -63,17 +64,17 @@ const sampleConfig = `
     ##   %{COMMON_LOG_FORMAT}   (plain apache & nginx access logs)
     ##   %{COMBINED_LOG_FORMAT} (access logs + referrer & agent)
     patterns = ["%{COMBINED_LOG_FORMAT}"]
-    
+
     ## Name of the outputted measurement name.
     measurement = "apache_access_log"
-    
+
     ## Full path(s) to custom pattern files.
     custom_pattern_files = []
-    
+
     ## Custom patterns can also be defined here. Put one pattern per line.
     custom_patterns = '''
-    
-    ## Timezone allows you to provide an override for timestamps that 
+
+    ## Timezone allows you to provide an override for timestamps that
     ## don't already include an offset
     ## e.g. 04/06/2016 12:41:45 data one two 5.43µs
     ##
@@ -207,9 +208,12 @@ func (l *LogParserPlugin) receiver(tailer *tail.Tail) {
 			continue
 		}
 
+		// Fix up files with Windows line endings.
+		text := strings.TrimRight(line.Text, "\r")
+
 		select {
 		case <-l.done:
-		case l.lines <- line.Text:
+		case l.lines <- text:
 		}
 	}
 }

plugins/inputs/tail/tail.go

@@ -2,6 +2,7 @@ package tail
 
 import (
 	"fmt"
+	"strings"
 	"sync"
 
 	"github.com/influxdata/tail"
@@ -123,7 +124,10 @@ func (t *Tail) receiver(tailer *tail.Tail) {
 				tailer.Filename, err))
 			continue
 		}
-		m, err = t.parser.ParseLine(line.Text)
+		// Fix up files with Windows line endings.
+		text := strings.TrimRight(line.Text, "\r")
+
+		m, err = t.parser.ParseLine(text)
 		if err == nil {
 			t.acc.AddFields(m.Name(), m.Fields(), m.Tags(), m.Time())
 		} else {

plugins/inputs/tail/tail_test.go

@@ -103,3 +103,33 @@ func TestTailBadLine(t *testing.T) {
 	acc.WaitError(1)
 	assert.Contains(t, acc.Errors[0].Error(), "E! Malformed log line")
 }
+
+func TestTailDosLineendings(t *testing.T) {
+	tmpfile, err := ioutil.TempFile("", "")
+	require.NoError(t, err)
+	defer os.Remove(tmpfile.Name())
+	_, err = tmpfile.WriteString("cpu usage_idle=100\r\ncpu2 usage_idle=200\r\n")
+	require.NoError(t, err)
+
+	tt := NewTail()
+	tt.FromBeginning = true
+	tt.Files = []string{tmpfile.Name()}
+	p, _ := parsers.NewInfluxParser()
+	tt.SetParser(p)
+	defer tt.Stop()
+	defer tmpfile.Close()
+
+	acc := testutil.Accumulator{}
+	require.NoError(t, tt.Start(&acc))
+	require.NoError(t, acc.GatherError(tt.Gather))
+
+	acc.Wait(2)
+	acc.AssertContainsFields(t, "cpu",
+		map[string]interface{}{
+			"usage_idle": float64(100),
+		})
+	acc.AssertContainsFields(t, "cpu2",
+		map[string]interface{}{
+			"usage_idle": float64(200),
+		})
+}