Validate that remote write queue settings are not negative (#3213)

exporter/prometheusremotewriteexporter/config.go

@@ -15,6 +15,8 @@
 package prometheusremotewriteexporter
 
 import (
+	"fmt"
+
 	"go.opentelemetry.io/collector/config"
 	"go.opentelemetry.io/collector/config/confighttp"
 	"go.opentelemetry.io/collector/exporter/exporterhelper"
@@ -63,5 +65,11 @@ var _ config.Exporter = (*Config)(nil)
 
 // Validate checks if the exporter configuration is valid
 func (cfg *Config) Validate() error {
+	if cfg.RemoteWriteQueue.QueueSize < 0 {
+		return fmt.Errorf("remote write queue size can't be negative")
+	}
+	if cfg.RemoteWriteQueue.NumConsumers < 0 {
+		return fmt.Errorf("remote write consumer number can't be negative")
+	}
 	return nil
 }

exporter/prometheusremotewriteexporter/config_test.go

@@ -82,3 +82,23 @@ func Test_loadConfig(t *testing.T) {
 			ResourceToTelemetrySettings: exporterhelper.ResourceToTelemetrySettings{Enabled: true},
 		})
 }
+
+func TestNegativeQueueSize(t *testing.T) {
+	factories, err := componenttest.NopFactories()
+	assert.NoError(t, err)
+
+	factory := NewFactory()
+	factories.Exporters[typeStr] = factory
+	_, err = configtest.LoadConfigFile(t, path.Join(".", "testdata", "negative_queue_size.yaml"), factories)
+	assert.Error(t, err)
+}
+
+func TestNegativeNumConsumers(t *testing.T) {
+	factories, err := componenttest.NopFactories()
+	assert.NoError(t, err)
+
+	factory := NewFactory()
+	factories.Exporters[typeStr] = factory
+	_, err = configtest.LoadConfigFile(t, path.Join(".", "testdata", "negative_num_consumers.yaml"), factories)
+	assert.Error(t, err)
+}

exporter/prometheusremotewriteexporter/testdata/negative_num_consumers.yaml

@@ -0,0 +1,21 @@
+receivers:
+    nop:
+
+processors:
+    nop:
+
+exporters:
+    prometheusremotewrite:
+        endpoint: "localhost:8888"
+        remote_write_queue:
+            queue_size: 5
+            num_consumers: -1
+
+service:
+    pipelines:
+        metrics:
+            receivers: [nop]
+            processors: [nop]
+            exporters: [prometheusremotewrite]
+
+

exporter/prometheusremotewriteexporter/testdata/negative_queue_size.yaml

@@ -0,0 +1,21 @@
+receivers:
+    nop:
+
+processors:
+    nop:
+
+exporters:
+    prometheusremotewrite:
+        endpoint: "localhost:8888"
+        remote_write_queue:
+            queue_size: -1
+            num_consumers: 10
+
+service:
+    pipelines:
+        metrics:
+            receivers: [nop]
+            processors: [nop]
+            exporters: [prometheusremotewrite]
+
+