[7.x] Add ID processor (#14524)

CHANGELOG.next.asciidoc

@@ -353,6 +353,7 @@ https://github.com/elastic/beats/compare/v7.0.0-alpha2...master[Check the HEAD d
 - Add consumer_lag in Kafka consumergroup metricset {pull}14822[14822]
 - Make use of consumer_lag in Kafka dashboard {pull}14863[14863]
 - Refactor kubernetes autodiscover to enable different resource based discovery {pull}14738[14738]
+- Add `add_id` processor. {pull}14524[14524]
 
 *Auditbeat*
 

libbeat/docs/processors-list.asciidoc

@@ -14,6 +14,9 @@ endif::[]
 ifndef::no_add_host_metadata_processor[]
 * <<add-host-metadata,`add_host_metadata`>>
 endif::[]
+ifndef::no_add_id_processor[]
+* <<add-id,`add_id`>>
+endif::[]
 ifndef::no_add_kubernetes_metadata_processor[]
 * <<add-kubernetes-metadata,`add_kubernetes_metadata`>>
 endif::[]
@@ -101,6 +104,9 @@ endif::[]
 ifndef::no_add_host_metadata_processor[]
 include::{libbeat-processors-dir}/add_host_metadata/docs/add_host_metadata.asciidoc[]
 endif::[]
+ifndef::no_add_id[]
+include::{libbeat-processors-dir}/add_id/docs/add_id.asciidoc[]
+endif::[]
 ifndef::no_add_kubernetes_metadata_processor[]
 include::{libbeat-processors-dir}/add_kubernetes_metadata/docs/add_kubernetes_metadata.asciidoc[]
 endif::[]

libbeat/processors/add_id/add_id.go

@@ -0,0 +1,76 @@
+// Licensed to Elasticsearch B.V. under one or more contributor
+// license agreements. See the NOTICE file distributed with
+// this work for additional information regarding copyright
+// ownership. Elasticsearch B.V. licenses this file to you under
+// the Apache License, Version 2.0 (the "License"); you may
+// not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+package add_id
+
+import (
+	"fmt"
+
+	"github.com/elastic/beats/libbeat/processors/add_id/generator"
+
+	"github.com/elastic/beats/libbeat/beat"
+	"github.com/elastic/beats/libbeat/common"
+	"github.com/elastic/beats/libbeat/processors"
+	jsprocessor "github.com/elastic/beats/libbeat/processors/script/javascript/module/processor"
+)
+
+func init() {
+	processors.RegisterPlugin("add_id", New)
+	jsprocessor.RegisterPlugin("AddID", New)
+}
+
+const processorName = "add_id"
+
+type addID struct {
+	config config
+	gen    generator.IDGenerator
+}
+
+// New constructs a new Add ID processor.
+func New(cfg *common.Config) (processors.Processor, error) {
+	config := defaultConfig()
+	if err := cfg.Unpack(&config); err != nil {
+		return nil, makeErrConfigUnpack(err)
+	}
+
+	gen, err := generator.Factory(config.Type)
+	if err != nil {
+		return nil, makeErrComputeID(err)
+	}
+
+	p := &addID{
+		config,
+		gen,
+	}
+
+	return p, nil
+}
+
+// Run enriches the given event with an ID
+func (p *addID) Run(event *beat.Event) (*beat.Event, error) {
+	id := p.gen.NextID()
+
+	if _, err := event.PutValue(p.config.TargetField, id); err != nil {
+		return nil, makeErrComputeID(err)
+	}
+
+	return event, nil
+}
+
+func (p *addID) String() string {
+	return fmt.Sprintf("%v=[target_field=[%v]]", processorName, p.config.TargetField)
+}

libbeat/processors/add_id/add_id_test.go

@@ -0,0 +1,65 @@
+// Licensed to Elasticsearch B.V. under one or more contributor
+// license agreements. See the NOTICE file distributed with
+// this work for additional information regarding copyright
+// ownership. Elasticsearch B.V. licenses this file to you under
+// the Apache License, Version 2.0 (the "License"); you may
+// not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+package add_id
+
+import (
+	"testing"
+
+	"github.com/elastic/beats/libbeat/common"
+
+	"github.com/elastic/beats/libbeat/beat"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestDefaultTargetField(t *testing.T) {
+	p, err := New(common.MustNewConfigFrom(nil))
+	assert.NoError(t, err)
+
+	testEvent := &beat.Event{}
+
+	newEvent, err := p.Run(testEvent)
+	assert.NoError(t, err)
+
+	v, err := newEvent.GetValue("@metadata.id")
+	assert.NoError(t, err)
+	assert.NotEmpty(t, v)
+}
+
+func TestNonDefaultTargetField(t *testing.T) {
+	cfg := common.MustNewConfigFrom(common.MapStr{
+		"target_field": "foo",
+	})
+	p, err := New(cfg)
+	assert.NoError(t, err)
+
+	testEvent := &beat.Event{
+		Fields: common.MapStr{},
+	}
+
+	newEvent, err := p.Run(testEvent)
+	assert.NoError(t, err)
+
+	v, err := newEvent.GetValue("foo")
+	assert.NoError(t, err)
+	assert.NotEmpty(t, v)
+
+	v, err = newEvent.GetValue("@metadata.id")
+	assert.NoError(t, err)
+	assert.Empty(t, v)
+}

libbeat/processors/add_id/config.go

@@ -0,0 +1,44 @@
+// Licensed to Elasticsearch B.V. under one or more contributor
+// license agreements. See the NOTICE file distributed with
+// this work for additional information regarding copyright
+// ownership. Elasticsearch B.V. licenses this file to you under
+// the Apache License, Version 2.0 (the "License"); you may
+// not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+package add_id
+
+import (
+	"github.com/elastic/beats/libbeat/processors/add_id/generator"
+)
+
+// configuration for Add ID processor.
+type config struct {
+	TargetField string `config:"target_field"` // Target field for the ID
+	Type        string `config:"type"`         // Type of ID
+}
+
+func defaultConfig() config {
+	return config{
+		TargetField: "@metadata.id",
+		Type:        "elasticsearch",
+	}
+}
+
+func (c *config) Validate() error {
+	// Validate type of ID generator
+	if !generator.Exists(c.Type) {
+		return makeErrUnknownType(c.Type)
+	}
+
+	return nil
+}

libbeat/processors/add_id/docs/add_id.asciidoc

@@ -0,0 +1,18 @@
+[[add-id]]
+=== Generate an ID for an event
+
+The `add_id` processor generates a unique ID for an event.
+
+[source,yaml]
+-----------------------------------------------------
+processors:
+ - add_id: ~
+-----------------------------------------------------
+
+The following settings are supported:
+
+`target_field`:: (Optional) Field where the generated ID will be stored. Default is `@metadata.id`.
+
+`type`:: (Optional) Type of ID to generate. Currently only `elasticsearch` is supported and is the default.
+The `elasticsearch` type generates IDs using the same algorithm that Elasticsearch uses for auto-generating
+document IDs.

libbeat/processors/add_id/errors.go

@@ -0,0 +1,55 @@
+// Licensed to Elasticsearch B.V. under one or more contributor
+// license agreements. See the NOTICE file distributed with
+// this work for additional information regarding copyright
+// ownership. Elasticsearch B.V. licenses this file to you under
+// the Apache License, Version 2.0 (the "License"); you may
+// not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+package add_id
+
+import (
+	"fmt"
+)
+
+type (
+	errConfigUnpack struct{ cause error }
+	errComputeID    struct{ cause error }
+	errUnknownType  struct{ typ string }
+)
+
+func makeErrConfigUnpack(cause error) errConfigUnpack {
+	return errConfigUnpack{cause}
+}
+func (e errConfigUnpack) Error() string {
+	return fmt.Sprintf("failed to unpack %v processor configuration: %v", processorName, e.cause)
+}
+func (e errConfigUnpack) Unwrap() error {
+	return e.cause
+}
+
+func makeErrComputeID(cause error) errComputeID {
+	return errComputeID{cause}
+}
+func (e errComputeID) Error() string {
+	return fmt.Sprintf("failed to compute ID: %v", e.cause)
+}
+func (e errComputeID) Unwrap() error {
+	return e.cause
+}
+
+func makeErrUnknownType(typ string) errUnknownType {
+	return errUnknownType{typ}
+}
+func (e errUnknownType) Error() string {
+	return fmt.Sprintf("invalid type [%s]", e.typ)
+}

libbeat/processors/add_id/generator/errors.go

@@ -0,0 +1,33 @@
+// Licensed to Elasticsearch B.V. under one or more contributor
+// license agreements. See the NOTICE file distributed with
+// this work for additional information regarding copyright
+// ownership. Elasticsearch B.V. licenses this file to you under
+// the Apache License, Version 2.0 (the "License"); you may
+// not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+package generator
+
+import (
+	"fmt"
+)
+
+type (
+	errUnknownType struct{ typ string }
+)
+
+func makeErrUnknownType(typ string) errUnknownType {
+	return errUnknownType{typ}
+}
+func (e errUnknownType) Error() string {
+	return fmt.Sprintf("invalid type [%s]", e.typ)
+}