feat: pass the interval though env var to integrations (newrelic#511)

* feat: pass the interval though env var to integrations

* test: check default and 0 intervals

* test: add test to cmd channnel

internal/agent/cmdchannel/runintegration/runintegration_test.go

@@ -5,6 +5,7 @@ package runintegration
 import (
 	"context"
 	"testing"
+	"time"
 
 	"github.com/newrelic/infrastructure-agent/internal/agent/cmdchannel"
 	"github.com/newrelic/infrastructure-agent/internal/integrations/v4/integration"
@@ -52,6 +53,7 @@ func TestHandle_queuesIntegrationToBeRun(t *testing.T) {
 
 	d := <-defQueue
 	assert.Equal(t, "nri-process-discovery", d.Name)
+	assert.Equal(t, time.Duration(0), d.Interval)
 	// Definition won't allow assert further
 }
 

internal/integrations/v4/integration/integration.go

@@ -24,6 +24,7 @@ const (
 	defaultIntegrationInterval = config.FREQ_PLUGIN_EXTERNAL_PLUGINS * time.Second
 	defaultTimeout             = 120 * time.Second
 	minimumTimeout             = 100 * time.Millisecond
+	intervalEnvVarName         = "NRI_CONFIG_INTERVAL"
 )
 
 var minimumIntegrationIntervalOverride = ""
@@ -61,6 +62,11 @@ func newDefinitionWithoutLookup(ce config2.ConfigEntry, passthroughEnv []string,
 	if err := ce.Sanitize(); err != nil {
 		return Definition{}, err
 	}
+
+	interval := getInterval(ce.Interval)
+	// Reading this env the integration can know configured interval.
+	ce.Env[intervalEnvVarName] = fmt.Sprintf("%v", interval)
+
 	d := Definition{
 		ExecutorConfig: executor.Config{
 			User:        ce.User,
@@ -70,7 +76,7 @@ func newDefinitionWithoutLookup(ce config2.ConfigEntry, passthroughEnv []string,
 		},
 		Labels:         ce.Labels,
 		Name:           ce.InstanceName,
-		Interval:       getInterval(ce.Interval),
+		Interval:       interval,
 		WhenConditions: conditions(ce.When),
 		ConfigTemplate: configTemplate,
 		newTempFile:    newTempFile,

internal/integrations/v4/integration/integration_test.go

@@ -4,6 +4,7 @@ package integration
 
 import (
 	"context"
+	"fmt"
 	"io/ioutil"
 	"runtime"
 	"testing"
@@ -163,6 +164,33 @@ func TestTimeout_Default(t *testing.T) {
 	// THEN the integration has a default timeout
 	assert.Equal(t, defaultTimeout, i.Timeout)
 }
+func TestInterval_EnvironmentVariableCustom(t *testing.T) {
+	// GIVEN a configuration with custom interval
+	// WHEN an integration is loaded from it
+	i, err := NewDefinition(config2.ConfigEntry{InstanceName: "foo", Interval: "55s", Exec: config2.ShlexOpt{"bar"}}, ErrLookup, nil, nil)
+	require.NoError(t, err)
+
+	// THEN the integration has an environment variable with the interval value
+	assert.Equal(t, "55s", i.ExecutorConfig.Environment[intervalEnvVarName])
+}
+func TestInterval_EnvironmentVariableCero(t *testing.T) {
+	// GIVEN a configuration with custom interval
+	// WHEN an integration is loaded from it
+	i, err := NewDefinition(config2.ConfigEntry{InstanceName: "foo", Interval: "0", Exec: config2.ShlexOpt{"bar"}}, ErrLookup, nil, nil)
+	require.NoError(t, err)
+
+	// THEN the integration has an environment variable with the interval value
+	assert.Equal(t, "0s", i.ExecutorConfig.Environment[intervalEnvVarName])
+}
+func TestInterval_EnvironmentVariableDefault(t *testing.T) {
+	// GIVEN a configuration with custom interval
+	// WHEN an integration is loaded from it
+	i, err := NewDefinition(config2.ConfigEntry{InstanceName: "foo", Exec: config2.ShlexOpt{"bar"}}, ErrLookup, nil, nil)
+	require.NoError(t, err)
+
+	// THEN the integration has an environment variable with the interval value
+	assert.Equal(t, fmt.Sprintf("%v", defaultIntegrationInterval), i.ExecutorConfig.Environment[intervalEnvVarName])
+}
 
 func TestTimeout_TooLow(t *testing.T) {
 	// GIVEN a configured timeout where the user forgot to write a suffix