add ignore_output feature, and additional error handling for lookups (#…

…52)
newrelic · Jan 8, 2020 · 37b7e5a · 37b7e5a
1 parent 50d56ea
commit 37b7e5a
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Showing 3 changed files with 21 additions and 6 deletions.
diff --git a/internal/config/fetch.go b/internal/config/fetch.go
@@ -136,7 +136,9 @@ func FetchLookups(cfg *load.Config, i int) bool {
 
 		loopNo := -1
 		combinations := [][]string{}
-		loopLookups(loopNo, sliceIndexes, sliceKeys, sliceLookups, &combinations)
+		if len(sliceLookups) > 0 {
+			loopLookups(loopNo, sliceIndexes, sliceKeys, sliceLookups, &combinations)
+		}
 
 		load.Logrus.WithFields(logrus.Fields{
 			"name": cfg.Name,
@@ -145,10 +147,16 @@ func FetchLookups(cfg *load.Config, i int) bool {
 		newAPIs := []string{}
 		for _, combo := range combinations {
 			tmpConfigWithLookupReplace := tmpCfgStr
-			for i, key := range lookupDimensions {
-				tmpConfigWithLookupReplace = strings.ReplaceAll(tmpConfigWithLookupReplace, fmt.Sprintf("${lookup:%v}", key), combo[i])
+			if len(combo) == len(lookupDimensions) {
+				for i, key := range lookupDimensions {
+					tmpConfigWithLookupReplace = strings.ReplaceAll(tmpConfigWithLookupReplace, fmt.Sprintf("${lookup:%v}", key), combo[i])
+				}
+				newAPIs = append(newAPIs, tmpConfigWithLookupReplace)
+			} else {
+				load.Logrus.WithFields(logrus.Fields{
+					"name": cfg.Name,
+				}).Debug("fetch: invalid lookup, missing a replace")
 			}
-			newAPIs = append(newAPIs, tmpConfigWithLookupReplace)
 		}
 
 		lookupConfig := load.Config{

diff --git a/internal/load/load.go b/internal/load/load.go
@@ -296,6 +296,7 @@ type API struct {
 	RemoveKeys   []string            `yaml:"remove_keys"`
 	KeepKeys     []string            `yaml:"keep_keys"`     // inverse of removing keys
 	SampleFilter []map[string]string `yaml:"sample_filter"` // sample filter key pair values with regex
+	IgnoreOutput bool                `yaml:"ignore_output"` // ignore the output completely, useful when creating lookups
 
 	// Debug Options
 	Debug   bool     `yaml:"debug"` // logs out additional data, should not be enabled for production use!

diff --git a/internal/processor/create.go b/internal/processor/create.go
@@ -83,9 +83,15 @@ func CreateMetricSets(samples []interface{}, config *load.Config, i int) {
 			RunSampleRenamer(api.RenameSamples, &currentSample, key, &eventType)
 		}
 
-		// check if this contains any key pair values to filter out
 		createSample := true
-		RunSampleFilter(currentSample, api.SampleFilter, &createSample)
+		// check if we should ignore this output completely
+		// useful when requests are made to generate a lookup, but the data is not needed
+		if api.IgnoreOutput {
+			createSample = false
+		} else {
+			// check if this contains any key pair values to filter out
+			RunSampleFilter(currentSample, api.SampleFilter, &createSample)
+		}
 
 		if createSample {
 			// remove keys from sample