[tailsamplingprocessor] Add gate for default OTTL error_mode ignore

processor/tailsamplingprocessor/README.md

@@ -37,11 +37,12 @@ Multiple policies exist today and it is straight forward to add more. These incl
 - `bytes_limiting`: Sample based on the rate of bytes per second using a token bucket algorithm implemented by golang.org/x/time/rate. This allows for burst traffic up to a configurable capacity while maintaining the average rate over time. The bucket is refilled continuously at the specified rate and has a maximum capacity for burst handling.
 - `span_count`: Sample based on the minimum and/or maximum number of spans, inclusive. If the sum of all spans in the trace is outside the range threshold, the trace will not be sampled.
 - `boolean_attribute`: Sample based on boolean attribute (resource and record).
-- `ottl_condition`: Sample based on given boolean OTTL condition (span and span event). Conditions may use OTTL path-based context names (e.g. `span.attributes["http.status_code"]`, `resource.attributes["service.name"]`, `spanevent.name`, `scope.name`). It is highly recommended to use this new syntax to avoid breaking changes in the future.
+- `ottl_condition`: Sample based on given boolean OTTL condition (span and span event). Conditions may use OTTL path-based context names (e.g. `span.attributes["http.status_code"]`, `resource.attributes["service.name"]`, `spanevent.name`, `scope.name`). It is highly recommended to use this new syntax to avoid breaking changes in the future. The `error_mode` defaults to `propagate`; this default will change to `ignore` when the `processor.tailsamplingprocessor.defaultErrorModeIgnore` feature gate is stable.
 - `and`: Sample based on multiple policies, creates an AND policy
 - `not`: Sample based on the opposite result a single policy, creates a NOT policy
 - `drop`: Drop (not sample) based on multiple policies, creates a DROP policy
 - `composite`: Sample based on a combination of above samplers, with ordering and rate allocation per sampler. Rate allocation allocates certain percentages of spans per policy order.
+
   For example if we have set max_total_spans_per_second as 100 then we can set rate_allocation as follows
   1. test-composite-policy-1 = 50 % of max_total_spans_per_second = 50 spans_per_second
   2. test-composite-policy-2 = 25 % of max_total_spans_per_second = 25 spans_per_second

processor/tailsamplingprocessor/config.go

@@ -296,6 +296,9 @@ type BooleanAttributeCfg struct {
 // OTTLConditionCfg holds the configurable setting to create a OTTL condition filter
 // sampling policy evaluator.
 type OTTLConditionCfg struct {
+	// ErrorMode determines how the processor reacts to errors that occur while processing an OTTL
+	// condition. The current default value is `propagate`, which will change to `ignore` when the
+	// `processor.tailsamplingprocessor.defaultErrorModeIgnore` feature gate is stable.
 	ErrorMode           ottl.ErrorMode `mapstructure:"error_mode"`
 	SpanConditions      []string       `mapstructure:"span"`
 	SpanEventConditions []string       `mapstructure:"spanevent"`

processor/tailsamplingprocessor/config.schema.yaml

@@ -262,6 +262,7 @@ $defs:
     type: object
     properties:
       error_mode:
+        description: ErrorMode determines how the processor reacts to errors that occur while processing an OTTL condition. The current default value is `propagate`, which will change to `ignore` when the `processor.tailsamplingprocessor.defaultErrorModeIgnore` feature gate is stable.
         $ref: /pkg/ottl.error_mode
       span:
         type: array

processor/tailsamplingprocessor/factory_test.go

@@ -13,8 +13,10 @@ import (
 	"go.opentelemetry.io/collector/component/componenttest"
 	"go.opentelemetry.io/collector/confmap/confmaptest"
 	"go.opentelemetry.io/collector/consumer/consumertest"
+	"go.opentelemetry.io/collector/featuregate"
 	"go.opentelemetry.io/collector/processor/processortest"
 
+	"github.com/open-telemetry/opentelemetry-collector-contrib/pkg/ottl"
 	"github.com/open-telemetry/opentelemetry-collector-contrib/processor/tailsamplingprocessor/internal/metadata"
 )
 
@@ -24,6 +26,18 @@ func TestCreateDefaultConfig(t *testing.T) {
 	assert.NoError(t, componenttest.CheckConfigStruct(cfg))
 }
 
+func TestDefaultOTTLConditionErrorMode(t *testing.T) {
+	t.Cleanup(func() {
+		_ = featuregate.GlobalRegistry().Set(metadata.ProcessorTailsamplingprocessorDefaultErrorModeIgnoreFeatureGate.ID(), false)
+	})
+
+	assert.Equal(t, ottl.PropagateError, defaultOTTLConditionErrorMode())
+
+	require.NoError(t, featuregate.GlobalRegistry().Set(metadata.ProcessorTailsamplingprocessorDefaultErrorModeIgnoreFeatureGate.ID(), true))
+
+	assert.Equal(t, ottl.IgnoreError, defaultOTTLConditionErrorMode())
+}
+
 func TestCreateProcessor(t *testing.T) {
 	cm, err := confmaptest.LoadConf(filepath.Join("testdata", "tail_sampling_config.yaml"))
 	require.NoError(t, err)

processor/tailsamplingprocessor/metadata.yaml

@@ -37,6 +37,12 @@ feature_gates:
     from_version: v0.150.0
     reference_url: https://github.com/open-telemetry/opentelemetry-collector-contrib/pull/47331
 
+  - id: "processor.tailsamplingprocessor.defaultErrorModeIgnore"
+    description: Changes the default error_mode of the tail sampling processor ottl_condition policy from propagate to ignore
+    stage: alpha
+    from_version: v0.153.0
+    reference_url: https://github.com/open-telemetry/opentelemetry-collector-contrib/issues/48420
+
 tests:
   config:
 

processor/tailsamplingprocessor/processor.go

@@ -24,6 +24,7 @@ import (
 	"go.opentelemetry.io/otel/trace"
 	"go.uber.org/zap"
 
+	"github.com/open-telemetry/opentelemetry-collector-contrib/pkg/ottl"
 	"github.com/open-telemetry/opentelemetry-collector-contrib/processor/tailsamplingprocessor/cache"
 	"github.com/open-telemetry/opentelemetry-collector-contrib/processor/tailsamplingprocessor/internal/idbatcher"
 	"github.com/open-telemetry/opentelemetry-collector-contrib/processor/tailsamplingprocessor/internal/metadata"
@@ -450,6 +451,9 @@ func getSharedPolicyEvaluator(settings component.TelemetrySettings, cfg *sharedP
 		return sampling.NewBooleanAttributeFilter(settings, bafCfg.Key, bafCfg.Value, bafCfg.InvertMatch), nil
 	case OTTLCondition:
 		ottlfCfg := cfg.OTTLConditionCfg
+		if ottlfCfg.ErrorMode == "" {
+			ottlfCfg.ErrorMode = defaultOTTLConditionErrorMode()
+		}
 		return sampling.NewOTTLConditionFilter(settings, ottlfCfg.SpanConditions, ottlfCfg.SpanEventConditions, ottlfCfg.ErrorMode)
 	case TraceFlags:
 		return sampling.NewTraceFlags(settings), nil
@@ -468,6 +472,13 @@ func getSharedPolicyEvaluator(settings component.TelemetrySettings, cfg *sharedP
 	}
 }
 
+func defaultOTTLConditionErrorMode() ottl.ErrorMode {
+	if metadata.ProcessorTailsamplingprocessorDefaultErrorModeIgnoreFeatureGate.IsEnabled() {
+		return ottl.IgnoreError
+	}
+	return ottl.PropagateError
+}
+
 type policyDecisionMetrics struct {
 	tracesSampled int
 	spansSampled  int64