[tcgc] add namespace flag

packages/typespec-client-generator-core/src/context.ts

@@ -79,6 +79,7 @@ export async function createSdkContext<
     decoratorsAllowList: [...defaultDecoratorsAllowList, ...(options?.additionalDecorators ?? [])],
     previewStringRegex: options?.versioning?.previewStringRegex || tcgcContext.previewStringRegex,
     disableUsageAccessPropagationToBase: options?.disableUsageAccessPropagationToBase ?? false,
+    namespace: context.options["namespace"],
   };
   sdkContext.sdkPackage = diagnostics.pipe(getSdkPackage(sdkContext));
   for (const client of sdkContext.sdkPackage.clients) {

packages/typespec-client-generator-core/src/decorators.ts

@@ -1113,9 +1113,16 @@ export function getClientNamespace(
   entity: Namespace | Interface | Model | Enum | Union,
 ): string {
   const override = getScopedDecoratorData(context, clientNamespaceKey, entity);
-  if (override) return override;
+  if (override) {
+    if (context.namespace && !override.startsWith(context.namespace)) {
+      if (context.namespace) {
+        throw new Error("The client namespace needs to correspond with the overwritten namespace.");
+      }
+    }
+    return override;
+  }
   if (!entity.namespace) {
-    return "";
+    return context.namespace || "";
   }
   if (entity.kind === "Namespace") {
     return getNamespaceFullNameWithOverride(context, entity);
@@ -1135,6 +1142,14 @@ function getNamespaceFullNameWithOverride(context: TCGCContext, namespace: Names
     segments.unshift(current.name);
     current = current.namespace;
   }
+  if (context.namespace) {
+    // if we override with namespace flag, we should override the global namespace to the namespace flag
+    const globalNamespaceName = getNamespaceFullName(context.program.getGlobalNamespaceType());
+    return segments
+      .join(".")
+      .replace(globalNamespaceName, context.namespace);
+  }
+
   return segments.join(".");
 }
 

packages/typespec-client-generator-core/src/interfaces.ts

@@ -55,6 +55,7 @@ export interface TCGCContext {
   previewStringRegex: RegExp;
   disableUsageAccessPropagationToBase: boolean;
   __pagedResultSet: Set<SdkType>;
+  namespace?: string;
 }
 
 export interface SdkContext<
@@ -77,6 +78,7 @@ export interface SdkEmitterOptions {
   "examples-directory"?: string;
   "examples-dir"?: string;
   "emitter-name"?: string;
+  namespace?: string;
 }
 
 export interface SdkClient {
@@ -772,6 +774,9 @@ export type SdkMethod<TServiceOperation extends SdkServiceOperation> =
 
 export interface SdkPackage<TServiceOperation extends SdkServiceOperation> {
   name: string;
+  /**
+   * @deprecated Look at `.namespaces` instead
+   */
   rootNamespace: string;
   clients: SdkClientType<TServiceOperation>[];
   models: SdkModelType[];

packages/typespec-client-generator-core/src/internal-utils.ts

@@ -2,6 +2,7 @@
   BooleanLiteral,
   createDiagnosticCollector,
   Diagnostic,
+  Enum,
   getDeprecationDetails,
   getNamespaceFullName,
   Interface,
@@ -27,11 +28,12 @@
   HttpOperationResponseContent,
 } from "@typespec/http";
 import { getAddedOnVersions, getRemovedOnVersions, getVersions } from "@typespec/versioning";
-import { getParamAlias } from "./decorators.js";
+import { getClientNamespace, getParamAlias } from "./decorators.js";
 import {
   DecoratorInfo,
   SdkBuiltInType,
   SdkClient,
+  SdkContext,
   SdkEnumType,
   SdkHttpResponse,
   SdkModelPropertyType,
@@ -83,6 +85,8 @@
 }
 
 /**
+ *
+ * @deprecated Use `.namespaces` from sdkContext.sdkPackage instead
  *
  * @param context
  * @param namespace If we know explicitly the namespace of the client, pass this in

packages/typespec-client-generator-core/src/lib.ts

@@ -13,6 +13,7 @@ const EmitterOptionsSchema: JSONSchemaType<SdkEmitterOptions> = {
     "examples-directory": { type: "string", nullable: true },
     "examples-dir": { type: "string", nullable: true },
     "emitter-name": { type: "string", nullable: true },
+    namespace: { type: "string", nullable: true },
   },
 };
 

packages/typespec-client-generator-core/src/package.ts

@@ -31,6 +31,8 @@ import {
   SdkBodyModelPropertyType,
   SdkClient,
   SdkClientType,
+  SdkContext,
+  SdkEmitterOptions,
   SdkEndpointParameter,
   SdkEndpointType,
   SdkEnumType,
@@ -807,7 +809,7 @@ function createSdkClientType<TServiceOperation extends SdkServiceOperation>(
     summary: getSummary(context.program, client.type),
     methods: [],
     apiVersions: context.__tspTypeToApiVersions.get(client.type)!,
-    nameSpace: getClientNamespaceStringHelper(context, client.service)!,
+    nameSpace: getClientNamespaceStringHelper(context, client.service)!, // eslint-disable-line @typescript-eslint/no-deprecated
     clientNamespace: getClientNamespace(context, client.type),
     initialization: diagnostics.pipe(getSdkInitializationType(context, client)),
     decorators: diagnostics.pipe(getTypeDecorators(context, client.type)),
@@ -897,17 +899,20 @@ function populateApiVersionInformation(context: TCGCContext): void {
   }
 }
 
-export function getSdkPackage<TServiceOperation extends SdkServiceOperation>(
-  context: TCGCContext,
+export function getSdkPackage<
+  TOptions extends Record<string, any> = SdkEmitterOptions,
+  TServiceOperation extends SdkServiceOperation = SdkHttpOperation,
+>(
+  context: SdkContext<TOptions, TServiceOperation>,
 ): [SdkPackage<TServiceOperation>, readonly Diagnostic[]] {
   const diagnostics = createDiagnosticCollector();
   populateApiVersionInformation(context);
   diagnostics.pipe(handleAllTypes(context));
   const crossLanguagePackageId = diagnostics.pipe(getCrossLanguagePackageId(context));
   const allReferencedTypes = getAllReferencedTypes(context);
   const sdkPackage: SdkPackage<TServiceOperation> = {
-    name: getClientNamespaceString(context)!,
-    rootNamespace: getClientNamespaceString(context)!,
+    name: getClientNamespaceString(context)!, // eslint-disable-line @typescript-eslint/no-deprecated
+    rootNamespace: getClientNamespaceString(context)!, // eslint-disable-line @typescript-eslint/no-deprecated
     clients: listClients(context).map((c) => diagnostics.pipe(createSdkClientType(context, c))),
     models: allReferencedTypes.filter((x): x is SdkModelType => x.kind === "model"),
     enums: allReferencedTypes.filter((x): x is SdkEnumType => x.kind === "enum"),
@@ -917,13 +922,14 @@ export function getSdkPackage<TServiceOperation extends SdkServiceOperation>(
     crossLanguagePackageId,
     namespaces: [],
   };
-  organizeNamespaces(sdkPackage);
+  organizeNamespaces(context, sdkPackage);
   return diagnostics.wrap(sdkPackage);
 }
 
-function organizeNamespaces<TServiceOperation extends SdkServiceOperation>(
-  sdkPackage: SdkPackage<TServiceOperation>,
-) {
+function organizeNamespaces<
+  TOptions extends Record<string, any> = SdkEmitterOptions,
+  TServiceOperation extends SdkServiceOperation = SdkHttpOperation,
+>(context: SdkContext<TOptions, TServiceOperation>, sdkPackage: SdkPackage<TServiceOperation>) {
   const clients = [...sdkPackage.clients];
   while (clients.length > 0) {
     const client = clients.shift()!;
@@ -944,7 +950,7 @@ function organizeNamespaces<TServiceOperation extends SdkServiceOperation>(
   }
 }
 
-function getSdkNamespace<TServiceOperation extends SdkServiceOperation>(
+function getSdkNamespace<TServiceOperation extends SdkServiceOperation = SdkHttpOperation>(
   sdkPackage: SdkPackage<TServiceOperation>,
   namespace: string,
 ) {

packages/typespec-client-generator-core/src/public-utils.ts

@@ -103,12 +103,15 @@
 /**
  * Get the client's namespace for generation. If package-name is passed in config, we return
  * that value as our namespace. Otherwise, we default to the TypeSpec service namespace.
+ * 
+ * @deprecated Access namespace information by iterating through `sdkPackage.namespaces` instead
+ * 
  * @param program
  * @param context
  * @returns
  */
 export function getClientNamespaceString(context: TCGCContext): string | undefined {
   return getClientNamespaceStringHelper(context, listServices(context.program)[0]?.type);
 }
 
 /**

packages/typespec-client-generator-core/test/packages/namespaces.test.ts

@@ -1,6 +1,7 @@
 import { ok, strictEqual } from "assert";
 import { beforeEach, describe, it } from "vitest";
-import { SdkTestRunner, createSdkTestRunner } from "../test-host.js";
+import { SdkEmitterOptions } from "../../src/interfaces.js";
+import { SdkTestRunner, createSdkContextTestHelper, createSdkTestRunner } from "../test-host.js";
 
 describe("typespec-client-generator-core: namespaces", () => {
   let runner: SdkTestRunner;
@@ -238,4 +239,77 @@ describe("typespec-client-generator-core: namespaces", () => {
     ok(petActionClient);
     strictEqual(petActionClient.clientNamespace, "PetStoreRenamed.SubNamespace");
   });
+
+  it("restructure client with namespace flag", async () => {
+    await runner.compile(
+      `
+      @service({
+        title: "Pet Store",
+      })
+      namespace PetStore;
+
+      @route("/feed")
+      op feed(): void;
+
+      @route("/op2")
+      op pet(): void;
+    `,
+    );
+    const sdkPackage = (
+      await createSdkContextTestHelper<SdkEmitterOptions>(runner.context.program, {
+        namespace: "PetStoreRenamed",
+      })
+    ).sdkPackage;
+    const foodClient = sdkPackage.clients.find((x) => x.name === "PetStoreRenamedClient");
+    ok(foodClient);
+    strictEqual(foodClient.clientNamespace, "PetStoreRenamed");
+  });
+
+  it("restructure client hierarchy with namespace flag, renaming of client name, and client namespace name", async () => {
+    await runner.compileWithCustomization(
+      `
+      @service({
+        title: "Pet Store",
+      })
+      namespace PetStore;
+
+      @route("/feed")
+      op feed(): void;
+
+      @route("/op2")
+      op pet(): void;
+    `,
+      `
+      namespace PetStoreRenamed; // this namespace will be the namespace of the clients and operation groups defined in this customization file
+
+      @client({
+        name: "FoodClient",
+        service: PetStore
+      })
+      interface Client1 {
+        feed is PetStore.feed
+      }
+
+      @client({
+        name: "PetActionClient",
+        service: PetStore
+      })
+      @clientNamespace("PetStoreRenamed.SubNamespace") // use @clientNamespace to specify the namespace of the client
+      interface Client2 {
+        pet is PetStore.pet
+      }
+    `,
+    );
+    const sdkPackage = (
+      await createSdkContextTestHelper<SdkEmitterOptions>(runner.context.program, {
+        namespace: "PetStoreRenamed",
+      })
+    ).sdkPackage;
+    const foodClient = sdkPackage.clients.find((x) => x.name === "FoodClient");
+    ok(foodClient);
+    strictEqual(foodClient.clientNamespace, "PetStoreRenamed");
+    const petActionClient = sdkPackage.clients.find((x) => x.name === "PetActionClient");
+    ok(petActionClient);
+    strictEqual(petActionClient.clientNamespace, "PetStoreRenamed.SubNamespace");
+  });
 });