Check unallow keys in @info decorator (#4505)

Fix #3887

---------

Co-authored-by: Kyle Zhang <[email protected]>
Co-authored-by: Timothee Guerin <[email protected]>

.chronus/changes/InfoUnallowKeyChecker-2024-8-24-11-6-11.md

@@ -0,0 +1,7 @@
+---
+changeKind: fix
+packages:
+  - "@typespec/openapi"
+---
+
+`@info` decorator validate no extra properties not starting with `x-` are provided.

packages/openapi/src/decorators.ts

@@ -1,6 +1,10 @@
 import {
+  compilerAssert,
   DecoratorContext,
+  Diagnostic,
+  DiagnosticTarget,
   getDoc,
+  getProperty,
   getService,
   getSummary,
   Model,
@@ -19,7 +23,7 @@ import {
   InfoDecorator,
   OperationIdDecorator,
 } from "../generated-defs/TypeSpec.OpenAPI.js";
-import { createStateSymbol, reportDiagnostic } from "./lib.js";
+import { createDiagnostic, createStateSymbol, reportDiagnostic } from "./lib.js";
 import { AdditionalInfo, ExtensionKey, ExternalDocs } from "./types.js";
 
 const operationIdsKey = createStateSymbol("operationIds");
@@ -185,6 +189,7 @@ export const $info: InfoDecorator = (
   if (data === undefined) {
     return;
   }
+  validateAdditionalInfoModel(context, model);
   if (data.termsOfService) {
     if (!validateIsUri(context, data.termsOfService, "TermsOfService")) {
       return;
@@ -233,3 +238,51 @@ function validateIsUri(context: DecoratorContext, url: string, propertyName: str
     return false;
   }
 }
+
+function validateAdditionalInfoModel(context: DecoratorContext, typespecType: TypeSpecValue) {
+  const propertyModel = context.program.resolveTypeReference(
+    "TypeSpec.OpenAPI.AdditionalInfo",
+  )[0]! as Model;
+
+  if (typeof typespecType === "object" && propertyModel) {
+    const diagnostics = checkNoAdditionalProperties(
+      typespecType,
+      context.getArgumentTarget(0)!,
+      propertyModel,
+    );
+    context.program.reportDiagnostics(diagnostics);
+  }
+}
+
+function checkNoAdditionalProperties(
+  typespecType: Type,
+  target: DiagnosticTarget,
+  source: Model,
+): Diagnostic[] {
+  const diagnostics: Diagnostic[] = [];
+  compilerAssert(typespecType.kind === "Model", "Expected type to be a Model.");
+
+  for (const [name, type] of typespecType.properties.entries()) {
+    const sourceProperty = getProperty(source, name);
+    if (sourceProperty) {
+      if (sourceProperty.type.kind === "Model") {
+        const nestedDiagnostics = checkNoAdditionalProperties(
+          type.type,
+          target,
+          sourceProperty.type,
+        );
+        diagnostics.push(...nestedDiagnostics);
+      }
+    } else if (!isOpenAPIExtensionKey(name)) {
+      diagnostics.push(
+        createDiagnostic({
+          code: "invalid-extension-key",
+          format: { value: name },
+          target,
+        }),
+      );
+    }
+  }
+
+  return diagnostics;
+}

packages/openapi/src/lib.ts

@@ -25,4 +25,4 @@ export const $lib = createTypeSpecLibrary({
   },
 });
 
-export const { reportDiagnostic, createStateSymbol } = $lib;
+export const { createDiagnostic, reportDiagnostic, createStateSymbol } = $lib;

packages/openapi/test/decorators.test.ts

@@ -152,6 +152,51 @@ describe("openapi: decorators", () => {
   });
 
   describe("@info", () => {
+    describe("emit diagnostics when passing extension key not starting with `x-` in additionalInfo", () => {
+      it.each([
+        ["root", `{ foo:"Bar" }`],
+        ["license", `{ license:{ name: "Apache 2.0", foo:"Bar"} }`],
+        ["contact", `{ contact:{ foo:"Bar"} }`],
+        ["complex", `{ contact:{ "x-custom": "string" }, foo:"Bar" }`],
+      ])("%s", async (_, code) => {
+        const diagnostics = await runner.diagnose(`
+        @info(${code})
+        @test namespace Service;
+      `);
+
+        expectDiagnostics(diagnostics, {
+          code: "@typespec/openapi/invalid-extension-key",
+          message: `OpenAPI extension must start with 'x-' but was 'foo'`,
+        });
+      });
+
+      it("multiple", async () => {
+        const diagnostics = await runner.diagnose(`
+          @info({
+            license:{ name: "Apache 2.0", foo1:"Bar"}, 
+            contact:{ "x-custom": "string", foo2:"Bar" }, 
+            foo3:"Bar" 
+          })
+          @test namespace Service;
+        `);
+
+        expectDiagnostics(diagnostics, [
+          {
+            code: "@typespec/openapi/invalid-extension-key",
+            message: `OpenAPI extension must start with 'x-' but was 'foo1'`,
+          },
+          {
+            code: "@typespec/openapi/invalid-extension-key",
+            message: `OpenAPI extension must start with 'x-' but was 'foo2'`,
+          },
+          {
+            code: "@typespec/openapi/invalid-extension-key",
+            message: `OpenAPI extension must start with 'x-' but was 'foo3'`,
+          },
+        ]);
+      });
+    });
+
     it("emit diagnostic if termsOfService is not a valid url", async () => {
       const diagnostics = await runner.diagnose(`
         @info({termsOfService:"notvalidurl"})