Strip trailing slash from OpenAPI server URLs (#4029)

.changeset/clean-servers-slash.md

@@ -0,0 +1,5 @@
+---
+"@gitbook/react-openapi": patch
+---
+
+Strip trailing slash from OpenAPI server URLs to avoid double slashes in rendered paths

packages/react-openapi/src/OpenAPIPathMultipleServers.tsx

@@ -7,7 +7,7 @@ import { OpenAPITooltip } from './OpenAPITooltip';
 import type { OpenAPIClientContext } from './context';
 import { formatPath } from './formatPath';
 import type { OpenAPIServerWithCustomProperties } from './types';
-import { getDefaultServerURL } from './util/server';
+import { getDefaultServerURL, interpolateServerURL } from './util/server';
 import { createStateKey } from './utils';
 
 export const serversStateKey = createStateKey('servers');
@@ -29,11 +29,14 @@ export function OpenAPIPathMultipleServers(
         .filter(
             (server): server is OpenAPIServerWithCustomProperties & { url: string } => !!server.url
         )
-        .map((server) => ({
-            key: server.url,
-            label: server.url,
-            description: server.description,
-        }));
+        .map((server) => {
+            const url = interpolateServerURL(server);
+            return {
+                key: url,
+                label: url,
+                description: server.description,
+            };
+        });
 
     return (
         <OpenAPIPathItem

packages/react-openapi/src/util/server.test.ts

@@ -23,6 +23,25 @@ describe('#interpolateServerURL', () => {
         expect(result).toBe('https://{username}.example.com/{basePath}');
     });
 
+    it('strips trailing slash from the server URL', () => {
+        const server: OpenAPIV3.ServerObject = {
+            url: '/butler/api/',
+        };
+        const result = interpolateServerURL(server);
+        expect(result).toBe('/butler/api');
+    });
+
+    it('strips trailing slash after variable interpolation', () => {
+        const server: OpenAPIV3.ServerObject = {
+            url: 'https://example.com/{basePath}/',
+            variables: {
+                basePath: { default: 'v1' },
+            },
+        };
+        const result = interpolateServerURL(server);
+        expect(result).toBe('https://example.com/v1');
+    });
+
     it('returns the URL with mixed placeholders and default values', () => {
         const server: OpenAPIV3.ServerObject = {
             url: 'https://{username}.example.com/{basePath}',

packages/react-openapi/src/util/server.ts

@@ -19,7 +19,7 @@ export function getDefaultServerURL(servers: OpenAPIV3.ServerObject[]): string {
 export function interpolateServerURL(server: OpenAPIV3.ServerObject) {
     const parts = parseServerURL(server?.url ?? '');
 
-    return parts
+    const url = parts
         .map((part) => {
             if (part.kind === 'text') {
                 return part.text;
@@ -27,6 +27,9 @@ export function interpolateServerURL(server: OpenAPIV3.ServerObject) {
             return server.variables?.[part.name]?.default ?? `{${part.name}}`;
         })
         .join('');
+
+    // Remove trailing slash to avoid double slashes when concatenated with paths
+    return url.endsWith('/') ? url.slice(0, -1) : url;
 }
 
 function parseServerURL(url: string) {