[receiver/netflow] Netflow receiver implementation - PR 2

.chloggen/netflow-receiver-implementation.yaml

@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: netflowreceiver
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Adds the implementation of the netflow receiver
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [32732]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext: The receiver now supports receiving NetFlow v5, NetFow v9, IPFIX, and sFlow v5 logs.
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: [user]

receiver/netflowreceiver/README.md

@@ -32,6 +32,11 @@ receivers:
       port: 2055
       sockets: 16
       workers: 32
+  netflow/sflow:
+    - scheme: sflow
+      port: 6343
+      sockets: 16
+      workers: 32
 
 processors:
   batch:
@@ -45,7 +50,7 @@ exporters:
 service:
   pipelines:
     logs:
-      receivers: [netflow]
+      receivers: [netflow, netflow/sflow]
       processors: [batch]
       exporters: [debug]
   telemetry:
@@ -61,42 +66,52 @@ You would then configure your network devices to send netflow, sflow, or ipfix d
 
 | Field | Description | Examples | Default |
 |-------|-------------|--------| ------- |
-| scheme | The type of flow data that to receive | `sflow`, `netflow`, `flow` | `netflow` |
+| scheme | The type of flow data that to receive | `sflow`, `netflow` | `netflow` |
 | hostname | The hostname or IP address to bind to | `localhost` | `0.0.0.0` |
 | port | The port to bind to | `2055` or `6343` | `2055` |
 | sockets | The number of sockets to use | 1 | 1 |
 | workers | The number of workers used to decode incoming flow messages | 2 | 2 |
-| queue_size | The size of the incoming netflow packets queue | 1000 | 1000000 |
+| queue_size | The size of the incoming netflow packets queue, it will always be at least 1000. | 5000 | 1000 |
 
 ## Data format
 
-The netflow data is standardized for the different schemas and is converted to OpenTelemetry logs following the [semantic conventions](https://opentelemetry.io/docs/specs/semconv/general/attributes/#server-client-and-shared-network-attributes)
-
-The output will adhere the format:
-
-```json
-{
-    "destination": {
-        "address": "192.168.0.1",
-        "port": 22
-    },
-    "flow": {
-        "end": 1731073104662487000,
-        "sampler_address": "192.168.0.2",
-        "sequence_num": 49,
-        "start": 1731073077662487000,
-        "time_received": 1731073138662487000,
-        "type": "NETFLOW_V5"
-    },
-    "io": {
-        "bytes": 529,
-        "packets": 378
-    },
-    "source": {
-        "address": "192.168.0.3",
-        "port": 40
-    },
-    "transport": "TCP",
-    "type": "IPv4"
-}
-```
+The netflow data is standardized for the different schemas and is converted to OpenTelemetry log records following the [semantic conventions](https://opentelemetry.io/docs/specs/semconv/general/attributes/#server-client-and-shared-network-attributes)
+
+The log record will have the following attributes (with examples):
+
+* **source.address**: Str(132.189.238.100)
+* **source.port**: Int(1255)
+* **destination.address**: Str(241.171.33.110)
+* **destination.port**: Int(64744)
+* **network.transport**: Str(tcp)
+* **network.type**: Str(ipv4)
+* **flow.io.bytes**: Int(853)
+* **flow.io.packets**: Int(83)
+* **flow.type**: Str(netflow_v5)
+* **flow.sequence_num**: Int(191)
+* **flow.time_received**: Int(1736309689918929427)
+* **flow.start**: Int(1736309689830846400)
+* **flow.end**: Int(1736309689871846400)
+* **flow.sampling_rate**: Int(0)
+* **flow.sampler_address**: Str(172.28.176.1)
+
+The log record timestamps will be:
+
+* **Observed timestamp**: The time the flow was received.
+* **Timestamp**: The flow `start` field.  
+
+### Schema support
+
+#### netflow
+
+* Process [Template Records](https://www.cisco.com/en/US/technologies/tk648/tk362/technologies_white_paper09186a00800a3db9.html) if present
+* Process Netflow V5, V9, and IPFIX messages
+* Extract the attributes documented above
+* Mapping of custom fields is not yet supported
+
+#### sflow
+
+* Process [sFlow version 5](https://sflow.org/sflow_version_5.txt) datagrams
+* `flow_sample` and `flow_sample_expanded` are supported.
+* `counter_sample` and `counter_sample_expanded` are NOT yet supported.
+* Mapping of custom fields is not yet supported

receiver/netflowreceiver/config.go

@@ -32,7 +32,7 @@ type Config struct {
 
 // Validate checks if the receiver configuration is valid
 func (cfg *Config) Validate() error {
-	validSchemes := [3]string{"sflow", "netflow", "flow"}
+	validSchemes := [2]string{"sflow", "netflow"}
 
 	validScheme := false
 	for _, scheme := range validSchemes {
@@ -42,7 +42,7 @@ func (cfg *Config) Validate() error {
 		}
 	}
 	if !validScheme {
-		return fmt.Errorf("scheme must be one of sflow, netflow, or flow")
+		return fmt.Errorf("scheme must be netflow or sflow")
 	}
 
 	if cfg.Sockets <= 0 {

receiver/netflowreceiver/config_test.go

@@ -36,7 +36,27 @@ func TestLoadConfig(t *testing.T) {
 				Port:      2055,
 				Sockets:   1,
 				Workers:   1,
-				QueueSize: 1000000,
+				QueueSize: 1000,
+			},
+		},
+		{
+			id: component.NewIDWithName(metadata.Type, "zero_queue"),
+			expected: &Config{
+				Scheme:    "netflow",
+				Port:      2055,
+				Sockets:   1,
+				Workers:   1,
+				QueueSize: 1000,
+			},
+		},
+		{
+			id: component.NewIDWithName(metadata.Type, "sflow"),
+			expected: &Config{
+				Scheme:    "sflow",
+				Port:      6343,
+				Sockets:   1,
+				Workers:   1,
+				QueueSize: 1000,
 			},
 		},
 	}
@@ -68,12 +88,20 @@ func TestInvalidConfig(t *testing.T) {
 	}{
 		{
 			id:  component.NewIDWithName(metadata.Type, "invalid_schema"),
-			err: "scheme must be one of sflow, netflow, or flow",
+			err: "scheme must be netflow or sflow",
 		},
 		{
 			id:  component.NewIDWithName(metadata.Type, "invalid_port"),
 			err: "port must be greater than 0",
 		},
+		{
+			id:  component.NewIDWithName(metadata.Type, "zero_sockets"),
+			err: "sockets must be greater than 0",
+		},
+		{
+			id:  component.NewIDWithName(metadata.Type, "zero_workers"),
+			err: "workers must be greater than 0",
+		},
 	}
 
 	for _, tt := range tests {

receiver/netflowreceiver/factory.go

@@ -14,9 +14,12 @@ import (
 )
 
 const (
-	defaultSockets   = 1
-	defaultWorkers   = 2
-	defaultQueueSize = 1_000_000
+	defaultSockets = 1
+	defaultWorkers = 2
+	// The default UDP packet buffer size in GoFlow2 is 9000 bytes, which means
+	// that for a full queue of 1000 messages, the size in memory will be 9MB.
+	// Source: https://github.com/netsampler/goflow2/blob/v2.2.1/README.md#security-notes-and-assumptions
+	defaultQueueSize = 1_000
 )
 
 // NewFactory creates a factory for netflow receiver.
@@ -27,6 +30,8 @@ func NewFactory() receiver.Factory {
 		receiver.WithLogs(createLogsReceiver, metadata.LogsStability))
 }
 
+// Config defines configuration for netflow receiver.
+// By default we listen for netflow traffic on port 2055
 func createDefaultConfig() component.Config {
 	return &Config{
 		Scheme:    "netflow",
@@ -37,14 +42,15 @@ func createDefaultConfig() component.Config {
 	}
 }
 
+// createLogsReceiver creates a netflow receiver.
+// We also create the UDP receiver, which is the piece of software that actually listens
+// for incoming netflow traffic on an UDP port.
 func createLogsReceiver(_ context.Context, params receiver.Settings, cfg component.Config, consumer consumer.Logs) (receiver.Logs, error) {
-	logger := params.Logger
-	conf := cfg.(*Config)
+	conf := *(cfg.(*Config))
 
-	nr := &netflowReceiver{
-		logger:      logger,
-		logConsumer: consumer,
-		config:      conf,
+	nr, err := newNetflowLogsReceiver(params, conf, consumer)
+	if err != nil {
+		return nil, err
 	}
 
 	return nr, nil

receiver/netflowreceiver/go.mod

@@ -3,14 +3,17 @@ module github.com/open-telemetry/opentelemetry-collector-contrib/receiver/netflo
 go 1.22.0
 
 require (
+	github.com/netsampler/goflow2/v2 v2.2.1
 	github.com/stretchr/testify v1.10.0
 	go.opentelemetry.io/collector/component v0.118.1-0.20250121185328-fbefb22cc2b3
 	go.opentelemetry.io/collector/component/componenttest v0.118.1-0.20250121185328-fbefb22cc2b3
 	go.opentelemetry.io/collector/confmap v1.24.1-0.20250121185328-fbefb22cc2b3
 	go.opentelemetry.io/collector/consumer v1.24.1-0.20250121185328-fbefb22cc2b3
 	go.opentelemetry.io/collector/consumer/consumertest v0.118.1-0.20250121185328-fbefb22cc2b3
+	go.opentelemetry.io/collector/pdata v1.24.1-0.20250121185328-fbefb22cc2b3
 	go.opentelemetry.io/collector/receiver v0.118.1-0.20250121185328-fbefb22cc2b3
 	go.opentelemetry.io/collector/receiver/receivertest v0.118.1-0.20250121185328-fbefb22cc2b3
+	go.opentelemetry.io/collector/semconv v0.118.1-0.20250121185328-fbefb22cc2b3
 	go.uber.org/goleak v1.3.0
 	go.uber.org/zap v1.27.0
 )
@@ -26,6 +29,7 @@ require (
 	github.com/knadh/koanf/maps v0.1.1 // indirect
 	github.com/knadh/koanf/providers/confmap v0.1.0 // indirect
 	github.com/knadh/koanf/v2 v2.1.2 // indirect
+	github.com/libp2p/go-reuseport v0.4.0 // indirect
 	github.com/mitchellh/copystructure v1.2.0 // indirect
 	github.com/mitchellh/reflectwalk v1.0.2 // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
@@ -35,7 +39,6 @@ require (
 	go.opentelemetry.io/collector/config/configtelemetry v0.118.1-0.20250121185328-fbefb22cc2b3 // indirect
 	go.opentelemetry.io/collector/consumer/consumererror v0.118.1-0.20250121185328-fbefb22cc2b3 // indirect
 	go.opentelemetry.io/collector/consumer/xconsumer v0.118.1-0.20250121185328-fbefb22cc2b3 // indirect
-	go.opentelemetry.io/collector/pdata v1.24.1-0.20250121185328-fbefb22cc2b3 // indirect
 	go.opentelemetry.io/collector/pdata/pprofile v0.118.1-0.20250121185328-fbefb22cc2b3 // indirect
 	go.opentelemetry.io/collector/pipeline v0.118.1-0.20250121185328-fbefb22cc2b3 // indirect
 	go.opentelemetry.io/collector/receiver/xreceiver v0.118.1-0.20250121185328-fbefb22cc2b3 // indirect