Location parameter rfc3164 syslog (#11)

* Add optional location parameter for setting the timezone for rfc3164 syslog. Original implementation can be found here: https://github.com/observIQ/stanza/pull/247/commits

Author: Joseph Sirianni

CHANGELOG.md

@@ -4,6 +4,20 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## Unreleased
+
+### Added
+- Syslog operator RFC 3164 location parameter ([PR11](https://github.com/open-telemetry/opentelemetry-log-collection/pull/11))
+
+## [0.14.0] - 2020-02-02
+
+### Changed
+- Remove standalone agent functionality
+- Simplifies modules
+  - Combines `parser/syslog` and `input/windows` modules into the primary module
+  - Removes output operators that were previously separate modules
+  - Leaves `input/k8sevent` and `transformer/k8smetadata` as separate modules for now. These two have extensive dependencies and their usefulness in the collector needs to be discussed before merging or removing.
+
 ## [0.13.12] - 2020-01-26
 
 ### Changed

docs/operators/syslog_parser.md

@@ -13,6 +13,7 @@ The `syslog_parser` operator parses the string-type field selected by `parse_fro
 | `preserve_to` |                  | Preserves the unparsed value at the specified [field](/docs/types/field.md)                                                                                                                                                              |
 | `on_error`    | `send`           | The behavior of the operator if it encounters an error. See [on_error](/docs/types/on_error.md)                                                                                                                                          |
 | `protocol`    | required         | The protocol to parse the syslog messages as. Options are `rfc3164` and `rfc5424`                                                                                                                                                        |
+| `location`    | `UTC`            | The geographic location (timezone) to use when parsing the timestamp (Syslog RFC 3164 only). The available locations depend on the local IANA Time Zone database. [This page](https://en.wikipedia.org/wiki/List_of_tz_database_time_zones) contains many examples, such as `America/New_York`. |
 | `timestamp`   | `nil`            | An optional [timestamp](/docs/types/timestamp.md) block which will parse a timestamp field before passing the entry to the output operator                                                                                               |
 | `severity`    | `nil`            | An optional [severity](/docs/types/severity.md) block which will parse a severity field before passing the entry to the output operator                                                                                                  |
 | `if`          |                  | An [expression](/docs/types/expression.md) that, when set, will be evaluated to determine whether this operator should be used for the given entry. This allows you to do easy conditional parsing without branching logic with routers. |

operator/builtin/parser/syslog/syslog.go

@@ -43,6 +43,7 @@ type SyslogParserConfig struct {
 	helper.ParserConfig `yaml:",inline"`
 
 	Protocol string `json:"protocol,omitempty" yaml:"protocol,omitempty"`
+	Location string `json:"location,omitempty" yaml:"location,omitempty"`
 }
 
 // Build will build a JSON parser operator.
@@ -64,18 +65,28 @@ func (c SyslogParserConfig) Build(context operator.BuildContext) ([]operator.Ope
 		return nil, fmt.Errorf("missing field 'protocol'")
 	}
 
+	if c.Location == "" {
+		c.Location = "UTC"
+	}
+
+	location, err := time.LoadLocation(c.Location)
+	if err != nil {
+		return nil, err
+	}
+
 	syslogParser := &SyslogParser{
 		ParserOperator: parserOperator,
 		protocol:       c.Protocol,
+		location:       location,
 	}
 
 	return []operator.Operator{syslogParser}, nil
 }
 
-func buildMachine(protocol string) (sl.Machine, error) {
+func buildMachine(protocol string, location *time.Location) (sl.Machine, error) {
 	switch protocol {
 	case "rfc3164":
-		return rfc3164.NewMachine(), nil
+		return rfc3164.NewMachine(rfc3164.WithLocaleTimezone(location)), nil
 	case "rfc5424":
 		return rfc5424.NewMachine(), nil
 	default:
@@ -87,6 +98,7 @@ func buildMachine(protocol string) (sl.Machine, error) {
 type SyslogParser struct {
 	helper.ParserOperator
 	protocol string
+	location *time.Location
 }
 
 // Process will parse an entry field as syslog.
@@ -104,7 +116,7 @@ func (s *SyslogParser) parse(value interface{}) (interface{}, error) {
 		return nil, err
 	}
 
-	machine, err := buildMachine(s.protocol)
+	machine, err := buildMachine(s.protocol, s.location)
 	if err != nil {
 		return nil, err
 	}

operator/builtin/parser/syslog/syslog_test.go

@@ -25,13 +25,33 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
+func testLocations() (map[string]*time.Location, error) {
+	locations := map[string]string{
+		"utc":     "UTC",
+		"detroit": "America/Detroit",
+		"athens":  "Europe/Athens",
+	}
+
+	l := make(map[string]*time.Location)
+	for k, v := range locations {
+		var err error
+		if l[k], err = time.LoadLocation(v); err != nil {
+			return nil, err
+		}
+	}
+	return l, nil
+}
+
 func TestSyslogParser(t *testing.T) {
 	basicConfig := func() *SyslogParserConfig {
 		cfg := NewSyslogParserConfig("test_operator_id")
 		cfg.OutputIDs = []string{"fake"}
 		return cfg
 	}
 
+	location, err := testLocations()
+	require.NoError(t, err)
+
 	cases := []struct {
 		name                 string
 		config               *SyslogParserConfig
@@ -46,10 +66,51 @@ func TestSyslogParser(t *testing.T) {
 			func() *SyslogParserConfig {
 				cfg := basicConfig()
 				cfg.Protocol = "rfc3164"
+				cfg.Location = location["utc"].String()
 				return cfg
 			}(),
 			"<34>Jan 12 06:30:00 1.2.3.4 apache_server: test message",
-			time.Date(time.Now().Year(), 1, 12, 6, 30, 0, 0, time.UTC),
+			time.Date(time.Now().Year(), 1, 12, 6, 30, 0, 0, location["utc"]),
+			map[string]interface{}{
+				"appname":  "apache_server",
+				"facility": 4,
+				"hostname": "1.2.3.4",
+				"message":  "test message",
+				"priority": 34,
+			},
+			entry.Critical,
+			"crit",
+		},
+		{
+			"RFC3164Detroit",
+			func() *SyslogParserConfig {
+				cfg := basicConfig()
+				cfg.Protocol = "rfc3164"
+				cfg.Location = location["detroit"].String()
+				return cfg
+			}(),
+			"<34>Jan 12 06:30:00 1.2.3.4 apache_server: test message",
+			time.Date(time.Now().Year(), 1, 12, 6, 30, 0, 0, location["detroit"]),
+			map[string]interface{}{
+				"appname":  "apache_server",
+				"facility": 4,
+				"hostname": "1.2.3.4",
+				"message":  "test message",
+				"priority": 34,
+			},
+			entry.Critical,
+			"crit",
+		},
+		{
+			"RFC3164Athens",
+			func() *SyslogParserConfig {
+				cfg := basicConfig()
+				cfg.Protocol = "rfc3164"
+				cfg.Location = location["athens"].String()
+				return cfg
+			}(),
+			"<34>Jan 12 06:30:00 1.2.3.4 apache_server: test message",
+			time.Date(time.Now().Year(), 1, 12, 6, 30, 0, 0, location["athens"]),
 			map[string]interface{}{
 				"appname":  "apache_server",
 				"facility": 4,