fix: Handle @latest in Go feature server and pre-compile version regex

franciscojavierarceo · claude · franciscojavierarceo · commit 7dfc447e1165 · 2026-03-26T12:12:13.000-04:00
- Strip @latest suffix (equivalent to no version) instead of passing through as part of the FV name, which caused confusing "not found" errors - Pre-compile version tag regex to package-level var to avoid recompilation on every call in the hot path Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
diff --git a/go/internal/feast/onlineserving/serving.go b/go/internal/feast/onlineserving/serving.go
@@ -21,6 +21,8 @@ import (
 	"github.com/feast-dev/feast/go/types"
 )
 
+var versionTagRegex = regexp.MustCompile(`^[vV]\d+$`)
+
 /*
 FeatureVector type represent result of retrieving single feature for multiple rows.
 It can be imagined as a column in output dataframe / table.
@@ -494,14 +496,16 @@ func ParseFeatureReference(featureRef string) (featureViewName, featureName stri
 		featureName = parsedFeatureName[1]
 	}
 
-	// Reject @v<N> version qualifier — Go feature server does not support versioned reads
+	// Handle @version qualifier on feature view name
 	if atIdx := strings.Index(featureViewName, "@"); atIdx >= 0 {
 		suffix := featureViewName[atIdx+1:]
-		matched, _ := regexp.MatchString(`^[vV]\d+$`, suffix)
-		if matched {
+		if versionTagRegex.MatchString(suffix) {
 			e = fmt.Errorf("versioned feature refs (@%s) are not supported by the Go feature server", suffix)
 			return
 		}
+		if strings.EqualFold(suffix, "latest") {
+			featureViewName = featureViewName[:atIdx]
+		}
 	}
 	return
 }

Original file line number	Diff line number	Diff line change
`@@ -21,6 +21,8 @@ import (`
`21`	`21`	`"github.com/feast-dev/feast/go/types"`
`22`	`22`	`)`
`23`	`23`
	`24`	+var versionTagRegex = regexp.MustCompile(`^[vV]\d+$`)
	`25`	`+`
`24`	`26`	`/*`
`25`	`27`	`FeatureVector type represent result of retrieving single feature for multiple rows.`
`26`	`28`	`It can be imagined as a column in output dataframe / table.`
`@@ -494,14 +496,16 @@ func ParseFeatureReference(featureRef string) (featureViewName, featureName stri`
`494`	`496`	`featureName = parsedFeatureName[1]`
`495`	`497`	`}`
`496`	`498`
`497`		`- // Reject @v<N> version qualifier — Go feature server does not support versioned reads`
	`499`	`+ // Handle @version qualifier on feature view name`
`498`	`500`	`if atIdx := strings.Index(featureViewName, "@"); atIdx >= 0 {`
`499`	`501`	`suffix := featureViewName[atIdx+1:]`
`500`		- matched, _ := regexp.MatchString(`^[vV]\d+$`, suffix)
`501`		`- if matched {`
	`502`	`+ if versionTagRegex.MatchString(suffix) {`
`502`	`503`	`e = fmt.Errorf("versioned feature refs (@%s) are not supported by the Go feature server", suffix)`
`503`	`504`	`return`
`504`	`505`	`}`
	`506`	`+ if strings.EqualFold(suffix, "latest") {`
	`507`	`+ featureViewName = featureViewName[:atIdx]`
	`508`	`+ }`
`505`	`509`	`}`
`506`	`510`	`return`
`507`	`511`	`}`