List v1/versions routes based on source IP if found (#10603)

Routing using on source IP if found. This should distribute
the listing load for V1 and versioning on multiple nodes
evenly between different clients.

If source IP is not found from the http request header, then falls back
to bucket name instead.

cmd/bucket-listobjects-handlers.go

@@ -27,6 +27,7 @@ import (
 	"github.com/minio/minio/cmd/logger"
 
 	"github.com/minio/minio/pkg/bucket/policy"
+	"github.com/minio/minio/pkg/handlers"
 	"github.com/minio/minio/pkg/sync/errgroup"
 )
 
@@ -113,7 +114,12 @@ func (api objectAPIHandlers) ListObjectVersionsHandler(w http.ResponseWriter, r
 		return
 	}
 
-	if proxyRequestByBucket(ctx, w, r, bucket) {
+	// Forward the request using Source IP or bucket
+	forwardStr := handlers.GetSourceIPFromHeaders(r)
+	if forwardStr == "" {
+		forwardStr = bucket
+	}
+	if proxyRequestByStringHash(ctx, w, r, forwardStr) {
 		return
 	}
 
@@ -340,8 +346,8 @@ func proxyRequestByNodeIndex(ctx context.Context, w http.ResponseWriter, r *http
 	return proxyRequest(ctx, w, r, ep)
 }
 
-func proxyRequestByBucket(ctx context.Context, w http.ResponseWriter, r *http.Request, bucket string) (success bool) {
+func proxyRequestByStringHash(ctx context.Context, w http.ResponseWriter, r *http.Request, str string) (success bool) {
-	return proxyRequestByNodeIndex(ctx, w, r, crcHashMod(bucket, len(globalProxyEndpoints)))
+	return proxyRequestByNodeIndex(ctx, w, r, crcHashMod(str, len(globalProxyEndpoints)))
 }
 
 // ListObjectsV1Handler - GET Bucket (List Objects) Version 1.
@@ -382,7 +388,12 @@ func (api objectAPIHandlers) ListObjectsV1Handler(w http.ResponseWriter, r *http
 		return
 	}
 
-	if proxyRequestByBucket(ctx, w, r, bucket) {
+	// Forward the request using Source IP or bucket
+	forwardStr := handlers.GetSourceIPFromHeaders(r)
+	if forwardStr == "" {
+		forwardStr = bucket
+	}
+	if proxyRequestByStringHash(ctx, w, r, forwardStr) {
 		return
 	}
 

pkg/handlers/proxy.go

@@ -74,10 +74,9 @@ func GetSourceScheme(r *http.Request) string {
 	return scheme
 }
 
-// GetSourceIP retrieves the IP from the X-Forwarded-For, X-Real-IP and RFC7239
+// GetSourceIPFromHeaders retrieves the IP from the X-Forwarded-For, X-Real-IP
-// Forwarded headers (in that order), falls back to r.RemoteAddr when all
+// and RFC7239 Forwarded headers (in that order)
-// else fails.
+func GetSourceIPFromHeaders(r *http.Request) string {
-func GetSourceIP(r *http.Request) string {
 	var addr string
 
 	if fwd := r.Header.Get(xForwardedFor); fwd != "" {
@@ -106,6 +105,13 @@ func GetSourceIP(r *http.Request) string {
 		}
 	}
 
+	return addr
+}
+
+// GetSourceIP retrieves the IP from the request headers
+// and falls back to r.RemoteAddr when necessary.
+func GetSourceIP(r *http.Request) string {
+	addr := GetSourceIPFromHeaders(r)
 	if addr != "" {
 		return addr
 	}