feat: Add OTAP metric-name filtering support

rust/otap-dataflow/configs/README.md

@@ -34,6 +34,13 @@ Demonstrates the filter processor:
 
 - Generates fake data -> filter processor -> debug processor -> noop exporter
 
+### `fake-metric-filter-debug-noop.yaml`
+
+Demonstrates metric-name filtering:
+
+- Generates fake metrics -> filter processor by metric name -> debug processor
+  -> noop exporter
+
 ### `fake-transform-debug-noop.yaml`
 
 Demonstrate using the transform processor to transform data
@@ -80,11 +87,10 @@ Generates mixed-tenant traffic using weighted resource attribute rotation:
 
 The `resource_attributes` field accepts three forms:
 
-| Form | Description |
-| ---- | ----------- |
-| Single map | All batches carry the same attributes (weight 1) |
-| List of maps | Equal round-robin rotation across entries (weight 1 each) |
-| List of weighted entries (`attrs` + `weight`) | Each entry receives batches proportional to its weight |
+- Single map: all batches carry the same attributes (weight 1).
+- List of maps: equal round-robin rotation across entries (weight 1 each).
+- List of weighted entries (`attrs` + `weight`): each entry receives batches
+  proportional to its weight.
 
 > **Note:** `resource_attributes` only applies to `data_source: static`.
 > With `generation_strategy: pre_generated`, only the first attribute set is used.
@@ -163,14 +169,21 @@ Syslog/CEF receiver with performance metrics:
 To send a quick test message (UDP):
 
 ```bash
-echo "<134>$(date '+%b %d %H:%M:%S') testhost testtag: Test message" | nc -u -w1 127.0.0.1 5140
+echo "<134>$(date '+%b %d %H:%M:%S') testhost testtag: Test message" \
+  | nc -u -w1 127.0.0.1 5140
 ```
 
-For sustained load testing, see the [load generator](../../tools/pipeline_perf_test/load_generator/readme.md):
+For sustained load testing, see the
+[load generator](../../tools/pipeline_perf_test/load_generator/readme.md):
 
 ```bash
 cd tools/pipeline_perf_test/load_generator
-python loadgen.py --load-type syslog --syslog-server 127.0.0.1 --syslog-port 5140 --syslog-transport udp --duration 15
+python loadgen.py \
+  --load-type syslog \
+  --syslog-server 127.0.0.1 \
+  --syslog-port 5140 \
+  --syslog-transport udp \
+  --duration 15
 ```
 
 > **Note:** The default `syslog-perf.yaml` config only enables UDP.

rust/otap-dataflow/configs/fake-metric-filter-debug-noop.yaml

@@ -0,0 +1,50 @@
+version: otel_dataflow/v1
+engine: {}
+groups:
+  default:
+    pipelines:
+      main:
+        policies:
+          channel_capacity:
+              control:
+                node: 100
+                pipeline: 100
+              pdata: 128
+
+        nodes:
+          receiver:
+            type: receiver:traffic_generator
+            config:
+              data_source: static
+              traffic_config:
+                max_signal_count: 1000
+                max_batch_size: 100
+                signals_per_second: 100
+                metric_weight: 100
+                trace_weight: 0
+                log_weight: 0
+          filter:
+            type: processor:filter
+            config:
+              metrics:
+                include:
+                  match_type: strict
+                  metric_names:
+                    - http.server.request.count
+                    - process.cpu.utilization
+          debug:
+            type: processor:debug
+            config:
+              verbosity: detailed
+              mode: signal
+          noop:
+            type: exporter:noop
+            config:
+
+        connections:
+          - from: receiver
+            to: filter
+          - from: filter
+            to: debug
+          - from: debug
+            to: noop

rust/otap-dataflow/crates/core-nodes/src/processors/filter_processor/README.md

@@ -10,6 +10,16 @@ For reference please the golang version of the filter processor.
 
 ```yaml
 config:
+  metrics:
+    include:
+      match_type: strict
+      metric_names:
+        - http.server.request.count
+        - process.cpu.utilization
+    exclude:
+      match_type: regexp
+      metric_names:
+        - ^internal\..*$
   logs:
     include:
       match_type: strict
@@ -77,7 +87,15 @@ config:
           value: false
 ```
 
-Currently we don't support metric filtering
+For a runnable metric-name filter pipeline, see
+[`configs/fake-metric-filter-debug-noop.yaml`](../../../../configs/fake-metric-filter-debug-noop.yaml).
+
+### Metrics
+
+To filter metrics, define `metrics.include` or `metrics.exclude` with a
+`match_type` and `metric_names`. Supported `match_type` values are `strict` and
+`regexp`. When both `include` and `exclude` are defined, include filtering runs
+first, and exclude filtering is applied to that result.
 
 ### Logs
 

rust/otap-dataflow/crates/core-nodes/src/processors/filter_processor/config.rs

@@ -4,13 +4,14 @@
 //! Implementation of the configuration of the filter processor
 //!
 
-use otap_df_pdata::otap::filter::{logs::LogFilter, traces::TraceFilter};
+use otap_df_pdata::otap::filter::{logs::LogFilter, metrics::MetricFilter, traces::TraceFilter};
 
 use serde::Deserialize;
 
 #[derive(Debug, Clone, Deserialize)]
 pub struct Config {
-    // ToDo: add metrics
+    #[serde(default = "default_metric_filter")]
+    metrics: MetricFilter,
     #[serde(default = "default_log_filter")]
     logs: LogFilter,
     #[serde(default = "default_trace_filter")]
@@ -22,14 +23,40 @@ const fn default_log_filter() -> LogFilter {
     LogFilter::new(None, None, vec![])
 }
 
+/// create empty metric filter as default value
+const fn default_metric_filter() -> MetricFilter {
+    MetricFilter::new(None, None)
+}
+
 /// create empty trace filter as default value
 const fn default_trace_filter() -> TraceFilter {
     TraceFilter::new(None, None)
 }
 
 impl Config {
     pub const fn new(logs: LogFilter, traces: TraceFilter) -> Self {
-        Self { logs, traces }
+        Self {
+            metrics: MetricFilter::new(None, None),
+            logs,
+            traces,
+        }
+    }
+
+    pub const fn new_with_metrics(
+        metrics: MetricFilter,
+        logs: LogFilter,
+        traces: TraceFilter,
+    ) -> Self {
+        Self {
+            metrics,
+            logs,
+            traces,
+        }
+    }
+
+    #[must_use]
+    pub const fn metric_filters(&self) -> &MetricFilter {
+        &self.metrics
     }
 
     #[must_use]

rust/otap-dataflow/crates/core-nodes/src/processors/filter_processor/metrics.rs

@@ -12,13 +12,19 @@ pub struct FilterPdataMetrics {
     /// Number of log signals consumed
     #[metric(unit = "{log}")]
     pub log_signals_consumed: Counter<u64>,
+    /// Number of metric signals consumed
+    #[metric(unit = "{metric}")]
+    pub metric_signals_consumed: Counter<u64>,
     /// Number of span signals consumed
     #[metric(unit = "{span}")]
     pub span_signals_consumed: Counter<u64>,
 
     /// Number of log signals filtered
     #[metric(unit = "{log}")]
     pub log_signals_filtered: Counter<u64>,
+    /// Number of metric signals filtered
+    #[metric(unit = "{metric}")]
+    pub metric_signals_filtered: Counter<u64>,
     /// Number of span signals filtered
     #[metric(unit = "{span}")]
     pub span_signals_filtered: Counter<u64>,