From 40df91a3639e8bfd93c589d5fb3c8ff552c5232e Mon Sep 17 00:00:00 2001
From: "Nolann B." <100787331+nolannbiron@users.noreply.github.com>
Date: Mon, 26 May 2025 18:55:11 +0200
Subject: [PATCH] Deduplicate path parameters from OpenAPI spec (#3264)

---
 .changeset/violet-schools-care.md          |  5 +++++
 packages/react-openapi/src/OpenAPISpec.tsx | 22 +++++++++++++++++++++-
 2 files changed, 26 insertions(+), 1 deletion(-)
 create mode 100644 .changeset/violet-schools-care.md

diff --git a/.changeset/violet-schools-care.md b/.changeset/violet-schools-care.md
new file mode 100644
index 000000000..e77a98b5c
--- /dev/null
+++ b/.changeset/violet-schools-care.md
@@ -0,0 +1,5 @@
+---
+'@gitbook/react-openapi': patch
+---
+
+Deduplicate path parameters from OpenAPI spec
diff --git a/packages/react-openapi/src/OpenAPISpec.tsx b/packages/react-openapi/src/OpenAPISpec.tsx
index 49c41cda4..1e6e56269 100644
--- a/packages/react-openapi/src/OpenAPISpec.tsx
+++ b/packages/react-openapi/src/OpenAPISpec.tsx
@@ -18,7 +18,7 @@ export function OpenAPISpec(props: {
 
     const { operation } = data;
 
-    const parameters = operation.parameters ?? [];
+    const parameters = deduplicateParameters(operation.parameters ?? []);
     const parameterGroups = groupParameters(parameters, context);
 
     const securities = 'securities' in data ? data.securities : [];
@@ -113,3 +113,23 @@ function getParameterGroupName(paramIn: string, context: OpenAPIClientContext):
             return paramIn;
     }
 }
+
+/** Deduplicate parameters by name and in.
+ * Some specs have both parameters define at path and operation level.
+ * We only want to display one of them.
+ */
+function deduplicateParameters(parameters: OpenAPI.Parameters): OpenAPI.Parameters {
+    const seen = new Set();
+
+    return parameters.filter((param) => {
+        const key = `${param.name}:${param.in}`;
+
+        if (seen.has(key)) {
+            return false;
+        }
+
+        seen.add(key);
+
+        return true;
+    });
+}