Merge pull request #4200 from yyhhyyyyyy/fix/vertex-gateway-base-url

fix(vertex): honor custom base_url as gateway prefix

relay/channel/vertex/adaptor.go

@@ -134,47 +134,11 @@ func (a *Adaptor) getRequestUrl(info *relaycommon.RelayInfo, modelName, suffix s
 		a.AccountCredentials = *adc
 
 		if a.RequestMode == RequestModeGemini {
-			if region == "global" {
-				return fmt.Sprintf(
-					"https://aiplatform.googleapis.com/v1/projects/%s/locations/global/publishers/google/models/%s:%s",
-					adc.ProjectID,
-					modelName,
-					suffix,
-				), nil
-			} else {
-				return fmt.Sprintf(
-					"https://%s-aiplatform.googleapis.com/v1/projects/%s/locations/%s/publishers/google/models/%s:%s",
-					region,
-					adc.ProjectID,
-					region,
-					modelName,
-					suffix,
-				), nil
-			}
+			return BuildGoogleModelURL(info.ChannelBaseUrl, DefaultAPIVersion, adc.ProjectID, region, modelName, suffix), nil
 		} else if a.RequestMode == RequestModeClaude {
-			if region == "global" {
-				return fmt.Sprintf(
-					"https://aiplatform.googleapis.com/v1/projects/%s/locations/global/publishers/anthropic/models/%s:%s",
-					adc.ProjectID,
-					modelName,
-					suffix,
-				), nil
-			} else {
-				return fmt.Sprintf(
-					"https://%s-aiplatform.googleapis.com/v1/projects/%s/locations/%s/publishers/anthropic/models/%s:%s",
-					region,
-					adc.ProjectID,
-					region,
-					modelName,
-					suffix,
-				), nil
-			}
+			return BuildAnthropicModelURL(info.ChannelBaseUrl, DefaultAPIVersion, adc.ProjectID, region, modelName, suffix), nil
 		} else if a.RequestMode == RequestModeOpenSource {
-			return fmt.Sprintf(
-				"https://aiplatform.googleapis.com/v1beta1/projects/%s/locations/%s/endpoints/openapi/chat/completions",
-				adc.ProjectID,
-				region,
-			), nil
+			return BuildOpenSourceChatCompletionsURL(info.ChannelBaseUrl, adc.ProjectID, region), nil
 		}
 	} else {
 		var keyPrefix string
@@ -183,20 +147,17 @@ func (a *Adaptor) getRequestUrl(info *relaycommon.RelayInfo, modelName, suffix s
 		} else {
 			keyPrefix = "?"
 		}
-		if region == "global" {
+		if a.RequestMode == RequestModeGemini {
 			return fmt.Sprintf(
-				"https://aiplatform.googleapis.com/v1/publishers/google/models/%s:%s%skey=%s",
-				modelName,
-				suffix,
+				"%s%skey=%s",
+				BuildGoogleModelURL(info.ChannelBaseUrl, DefaultAPIVersion, "", region, modelName, suffix),
 				keyPrefix,
 				info.ApiKey,
 			), nil
-		} else {
+		} else if a.RequestMode == RequestModeClaude {
 			return fmt.Sprintf(
-				"https://%s-aiplatform.googleapis.com/v1/publishers/google/models/%s:%s%skey=%s",
-				region,
-				modelName,
-				suffix,
+				"%s%skey=%s",
+				BuildAnthropicModelURL(info.ChannelBaseUrl, DefaultAPIVersion, "", region, modelName, suffix),
 				keyPrefix,
 				info.ApiKey,
 			), nil

relay/channel/vertex/url_builder.go

@@ -0,0 +1,86 @@
+package vertex
+
+import (
+	"fmt"
+	"strings"
+)
+
+const (
+	DefaultAPIVersion    = "v1"
+	OpenSourceAPIVersion = "v1beta1"
+	PublisherGoogle      = "google"
+	PublisherAnthropic   = "anthropic"
+)
+
+func normalizeVertexBaseURL(baseURL string) string {
+	return strings.TrimRight(strings.TrimSpace(baseURL), "/")
+}
+
+func normalizeVertexRegion(region string) string {
+	region = strings.TrimSpace(region)
+	if region == "" {
+		return "global"
+	}
+	return region
+}
+
+func appendVertexAPIVersion(baseURL, version string) string {
+	version = strings.Trim(strings.TrimSpace(version), "/")
+	if version == "" {
+		return baseURL
+	}
+	if strings.HasSuffix(baseURL, "/"+version) {
+		return baseURL
+	}
+	return baseURL + "/" + version
+}
+
+func BuildAPIBaseURL(baseURL, version, projectID, region string) string {
+	if normalized := normalizeVertexBaseURL(baseURL); normalized != "" {
+		normalized = appendVertexAPIVersion(normalized, version)
+
+		region = normalizeVertexRegion(region)
+		if strings.TrimSpace(projectID) != "" {
+			normalized = fmt.Sprintf("%s/projects/%s/locations/%s", normalized, projectID, region)
+		}
+		return normalized
+	}
+
+	region = normalizeVertexRegion(region)
+	if strings.TrimSpace(projectID) == "" {
+		if region == "global" {
+			return fmt.Sprintf("https://aiplatform.googleapis.com/%s", version)
+		}
+		return fmt.Sprintf("https://%s-aiplatform.googleapis.com/%s", region, version)
+	}
+
+	if region == "global" {
+		return fmt.Sprintf("https://aiplatform.googleapis.com/%s/projects/%s/locations/global", version, projectID)
+	}
+	return fmt.Sprintf("https://%s-aiplatform.googleapis.com/%s/projects/%s/locations/%s", region, version, projectID, region)
+}
+
+func BuildPublisherModelURL(baseURL, version, projectID, region, publisher, modelName, action string) string {
+	return fmt.Sprintf(
+		"%s/publishers/%s/models/%s:%s",
+		BuildAPIBaseURL(baseURL, version, projectID, region),
+		publisher,
+		modelName,
+		action,
+	)
+}
+
+func BuildGoogleModelURL(baseURL, version, projectID, region, modelName, action string) string {
+	return BuildPublisherModelURL(baseURL, version, projectID, region, PublisherGoogle, modelName, action)
+}
+
+func BuildAnthropicModelURL(baseURL, version, projectID, region, modelName, action string) string {
+	return BuildPublisherModelURL(baseURL, version, projectID, region, PublisherAnthropic, modelName, action)
+}
+
+func BuildOpenSourceChatCompletionsURL(baseURL, projectID, region string) string {
+	return fmt.Sprintf(
+		"%s/endpoints/openapi/chat/completions",
+		BuildAPIBaseURL(baseURL, OpenSourceAPIVersion, projectID, region),
+	)
+}