[Filebeat] Update fileset input merging to replaces paths and append …

…processors. (#16450) (#16525)

* Update go-ucfg to 0.8.3 to use the new field merging adjustments. Update fileset input merging to replaces paths and append procesors.

* Add changelog entry.

(cherry picked from commit 9695092)

CHANGELOG.next.asciidoc

@@ -77,6 +77,7 @@ https://github.com/elastic/beats/compare/v7.0.0-alpha2...master[Check the HEAD d
 - Fix index names for indexing not always guaranteed to be lower case. {pull}16081[16081]
 - Upgrade go-ucfg to latest v0.8.1. {pull}15937{15937}
 - Fix loading processors from annotation hints. {pull}16348[16348]
+- Upgrade go-ucfg to latest v0.8.3. {pull}16450{16450}
 
 *Auditbeat*
 
@@ -103,6 +104,7 @@ https://github.com/elastic/beats/compare/v7.0.0-alpha2...master[Check the HEAD d
 - Fix mapping error for cloudtrail additionalEventData field {pull}16088[16088]
 - Fix a connection error in httpjson input. {pull}16123[16123]
 - Improve `elasticsearch/audit` fileset to handle timestamps correctly. {pull}15942[15942]
+- Fix merging of fileset inputs to replace paths and append processors. {pull}16450{16450}
 
 *Heartbeat*
 

NOTICE.txt

@@ -1518,8 +1518,8 @@ Apache License 2.0
 
 --------------------------------------------------------------------
 Dependency: github.com/elastic/go-ucfg
-Version: v0.8.2
-Revision: ab69586e10820006b250d04c98cc3b848e227808
+Version: v0.8.3
+Revision: f3ae3b220df32cfcae011ec6bbf87a711e6bf06b
 License type (autodetected): Apache-2.0
 ./vendor/github.com/elastic/go-ucfg/LICENSE:
 --------------------------------------------------------------------

filebeat/fileset/fileset.go

@@ -34,6 +34,8 @@ import (
 	"strings"
 	"text/template"
 
+	"github.com/elastic/go-ucfg"
+
 	errw "github.com/pkg/errors"
 	"gopkg.in/yaml.v2"
 
@@ -362,7 +364,7 @@ func (fs *Fileset) getInputConfig() (*common.Config, error) {
 		if err != nil {
 			return nil, fmt.Errorf("Error creating config from input overrides: %v", err)
 		}
-		cfg, err = common.MergeConfigs(cfg, overrides)
+		cfg, err = common.MergeConfigsWithOptions([]*common.Config{cfg, overrides}, ucfg.FieldReplaceValues("**.paths"), ucfg.FieldAppendValues("**.processors"))
 		if err != nil {
 			return nil, fmt.Errorf("Error applying config overrides: %v", err)
 		}

libbeat/common/config.go

@@ -116,6 +116,16 @@ func MergeConfigs(cfgs ...*Config) (*Config, error) {
 	return config, nil
 }
 
+func MergeConfigsWithOptions(cfgs []*Config, options ...ucfg.Option) (*Config, error) {
+	config := NewConfig()
+	for _, c := range cfgs {
+		if err := config.MergeWithOpts(c, options...); err != nil {
+			return nil, err
+		}
+	}
+	return config, nil
+}
+
 func NewConfigWithYAML(in []byte, source string) (*Config, error) {
 	opts := append(
 		[]ucfg.Option{
@@ -164,6 +174,14 @@ func (c *Config) Merge(from interface{}) error {
 	return c.access().Merge(from, configOpts...)
 }
 
+func (c *Config) MergeWithOpts(from interface{}, opts ...ucfg.Option) error {
+	o := configOpts
+	if opts != nil {
+		o = append(o, opts...)
+	}
+	return c.access().Merge(from, o...)
+}
+
 func (c *Config) Unpack(to interface{}) error {
 	return c.access().Unpack(to, configOpts...)
 }