[AGENTCFG-79] Remove usage of Viper from comp/logs/agent/config/parser.go

comp/logs/agent/config/go.mod

@@ -12,10 +12,10 @@ require (
 	github.com/DataDog/datadog-agent/pkg/util/log v0.64.0-devel
 	github.com/DataDog/datadog-agent/pkg/util/pointer v0.61.0
 	github.com/DataDog/datadog-agent/pkg/util/scrubber v0.62.3
-	github.com/DataDog/viper v1.14.0
 	github.com/stretchr/testify v1.10.0
 	go.uber.org/atomic v1.11.0
 	go.uber.org/fx v1.23.0
+	gopkg.in/yaml.v3 v3.0.1
 )
 
 require (
@@ -38,6 +38,7 @@ require (
 	github.com/DataDog/datadog-agent/pkg/util/system/socket v0.61.0 // indirect
 	github.com/DataDog/datadog-agent/pkg/util/winutil v0.61.0 // indirect
 	github.com/DataDog/datadog-agent/pkg/version v0.62.3 // indirect
+	github.com/DataDog/viper v1.14.0 // indirect
 	github.com/Microsoft/go-winio v0.6.2 // indirect
 	github.com/cihub/seelog v0.0.0-20170130134532-f561c5e57575 // indirect
 	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
@@ -72,7 +73,6 @@ require (
 	golang.org/x/sys v0.30.0 // indirect
 	golang.org/x/text v0.22.0 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
-	gopkg.in/yaml.v3 v3.0.1 // indirect
 )
 
 // This section was automatically added by 'invoke modules.add-all-replace' command, do not edit manually

comp/logs/agent/config/integration_config.go

@@ -42,22 +42,22 @@ type LogsConfig struct {
 	IntegrationName string
 
 	Port        int    // Network
-	IdleTimeout string `mapstructure:"idle_timeout" json:"idle_timeout"` // Network
+	IdleTimeout string `mapstructure:"idle_timeout" json:"idle_timeout" yaml:"idle_timeout"` // Network
 	Path        string // File, Journald
 
-	Encoding     string   `mapstructure:"encoding" json:"encoding"`             // File
-	ExcludePaths []string `mapstructure:"exclude_paths" json:"exclude_paths"`   // File
-	TailingMode  string   `mapstructure:"start_position" json:"start_position"` // File
+	Encoding     string           `mapstructure:"encoding" json:"encoding" yaml:"encoding"`                   // File
+	ExcludePaths StringSliceField `mapstructure:"exclude_paths" json:"exclude_paths" yaml:"exclude_paths"`    // File
+	TailingMode  string           `mapstructure:"start_position" json:"start_position" yaml:"start_position"` // File
 
 	//nolint:revive // TODO(AML) Fix revive linter
-	ConfigId           string   `mapstructure:"config_id" json:"config_id"`                   // Journald
-	IncludeSystemUnits []string `mapstructure:"include_units" json:"include_units"`           // Journald
-	ExcludeSystemUnits []string `mapstructure:"exclude_units" json:"exclude_units"`           // Journald
-	IncludeUserUnits   []string `mapstructure:"include_user_units" json:"include_user_units"` // Journald
-	ExcludeUserUnits   []string `mapstructure:"exclude_user_units" json:"exclude_user_units"` // Journald
-	IncludeMatches     []string `mapstructure:"include_matches" json:"include_matches"`       // Journald
-	ExcludeMatches     []string `mapstructure:"exclude_matches" json:"exclude_matches"`       // Journald
-	ContainerMode      bool     `mapstructure:"container_mode" json:"container_mode"`         // Journald
+	ConfigId           string           `mapstructure:"config_id" json:"config_id" yaml:"config_id"`                            // Journald
+	IncludeSystemUnits StringSliceField `mapstructure:"include_units" json:"include_units" yaml:"include_units"`                // Journald
+	ExcludeSystemUnits StringSliceField `mapstructure:"exclude_units" json:"exclude_units" yaml:"exclude_units"`                // Journald
+	IncludeUserUnits   StringSliceField `mapstructure:"include_user_units" json:"include_user_units" yaml:"include_user_units"` // Journald
+	ExcludeUserUnits   StringSliceField `mapstructure:"exclude_user_units" json:"exclude_user_units" yaml:"exclude_user_units"` // Journald
+	IncludeMatches     StringSliceField `mapstructure:"include_matches" json:"include_matches" yaml:"include_matches"`          // Journald
+	ExcludeMatches     StringSliceField `mapstructure:"exclude_matches" json:"exclude_matches" yaml:"exclude_matches"`          // Journald
+	ContainerMode      bool             `mapstructure:"container_mode" json:"container_mode" yaml:"container_mode"`             // Journald
 
 	Image string // Docker
 	Label string // Docker
@@ -67,7 +67,7 @@ type LogsConfig struct {
 	// determine the appropriate tags for the logs.
 	Identifier string // Docker, File
 
-	ChannelPath string `mapstructure:"channel_path" json:"channel_path"` // Windows Event
+	ChannelPath string `mapstructure:"channel_path" json:"channel_path" yaml:"channel_path"` // Windows Event
 	Query       string // Windows Event
 
 	// used as input only by the Channel tailer.
@@ -76,22 +76,49 @@ type LogsConfig struct {
 
 	// ChannelTags are the tags attached to messages on Channel; unlike Tags this can be
 	// modified at runtime (as long as ChannelTagsMutex is held).
-	ChannelTags []string
+	ChannelTags StringSliceField
 
 	// ChannelTagsMutex guards ChannelTags.
 	ChannelTagsMutex sync.Mutex
 
 	Service         string
 	Source          string
 	SourceCategory  string
-	Tags            []string
-	ProcessingRules []*ProcessingRule `mapstructure:"log_processing_rules" json:"log_processing_rules"`
+	Tags            StringSliceField
+	ProcessingRules []*ProcessingRule `mapstructure:"log_processing_rules" json:"log_processing_rules" yaml:"log_processing_rules"`
 	// ProcessRawMessage is used to process the raw message instead of only the content part of the message.
-	ProcessRawMessage *bool `mapstructure:"process_raw_message" json:"process_raw_message"`
+	ProcessRawMessage *bool `mapstructure:"process_raw_message" json:"process_raw_message" yaml:"process_raw_message"`
 
-	AutoMultiLine               *bool   `mapstructure:"auto_multi_line_detection" json:"auto_multi_line_detection"`
-	AutoMultiLineSampleSize     int     `mapstructure:"auto_multi_line_sample_size" json:"auto_multi_line_sample_size"`
-	AutoMultiLineMatchThreshold float64 `mapstructure:"auto_multi_line_match_threshold" json:"auto_multi_line_match_threshold"`
+	AutoMultiLine               *bool   `mapstructure:"auto_multi_line_detection" json:"auto_multi_line_detection" yaml:"auto_multi_line_detection"`
+	AutoMultiLineSampleSize     int     `mapstructure:"auto_multi_line_sample_size" json:"auto_multi_line_sample_size" yaml:"auto_multi_line_sample_size"`
+	AutoMultiLineMatchThreshold float64 `mapstructure:"auto_multi_line_match_threshold" json:"auto_multi_line_match_threshold" yaml:"auto_multi_line_match_threshold"`
+}
+
+// StringSliceField is a custom type for unmarshalling comma-separated string values or typical yaml fields into a slice of strings.
+type StringSliceField []string
+
+// UnmarshalYAML is a custom unmarshalling function is needed for string array fields to split comma-separated values.
+func (t *StringSliceField) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	var str string
+	if err := unmarshal(&str); err == nil {
+		// note that we are intentionally avoiding the trimming of any spaces whilst splitting the string
+		str = strings.ReplaceAll(str, "\n", "")
+		*t = strings.Split(str, ",")
+		return nil
+	}
+
+	var raw []interface{}
+	if err := unmarshal(&raw); err == nil {
+		for _, item := range raw {
+			if str, ok := item.(string); ok {
+				*t = append(*t, str)
+			} else {
+				return fmt.Errorf("cannot unmarshal %v into a string", item)
+			}
+		}
+		return nil
+	}
+	return fmt.Errorf("could not parse YAML config, please double check the yaml files")
 }
 
 // Dump dumps the contents of this struct to a string, for debugging purposes.

comp/logs/agent/config/parser.go

@@ -6,13 +6,15 @@
 package config
 
 import (
-	"bytes"
 	"encoding/json"
 	"fmt"
-
-	"github.com/DataDog/viper"
+	yaml "gopkg.in/yaml.v3"
 )
 
+type yamlLogsConfigsWrapper struct {
+	Logs []*LogsConfig
+}
+
 // ParseJSON parses the data formatted in JSON
 // returns an error if the parsing failed.
 func ParseJSON(data []byte) ([]*LogsConfig, error) {
@@ -24,23 +26,13 @@ func ParseJSON(data []byte) ([]*LogsConfig, error) {
 	return configs, nil
 }
 
-const yaml = "yaml"
-const logsPath = "logs"
-
 // ParseYAML parses the data formatted in YAML,
 // returns an error if the parsing failed.
 func ParseYAML(data []byte) ([]*LogsConfig, error) {
-	var configs []*LogsConfig
-	var err error
-	v := viper.New()
-	v.SetConfigType(yaml)
-	err = v.ReadConfig(bytes.NewBuffer(data))
+	var yamlConfigsWrapper yamlLogsConfigsWrapper
+	err := yaml.Unmarshal(data, &yamlConfigsWrapper)
 	if err != nil {
 		return nil, fmt.Errorf("could not decode YAML logs config: %v", err)
 	}
-	err = v.UnmarshalKey(logsPath, &configs)
-	if err != nil {
-		return nil, fmt.Errorf("could not parse YAML logs config: %v", err)
-	}
-	return configs, nil
+	return yamlConfigsWrapper.Logs, nil
 }