generating additional export statements package index (#303)

Author: AllanZhengYP

smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/CodegenVisitor.java

@@ -189,7 +189,7 @@ void execute() {
         }
 
         // Generate index for client.
-        IndexGenerator.writeIndex(settings, model, symbolProvider, fileManifest);
+        IndexGenerator.writeIndex(settings, model, symbolProvider, fileManifest, integrations);
 
         // Generate protocol tests IFF found in the model.
         if (protocolGenerator != null) {

smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/IndexGenerator.java

@@ -15,6 +15,7 @@
 
 package software.amazon.smithy.typescript.codegen;
 
+import java.util.List;
 import java.util.Set;
 import java.util.TreeSet;
 import software.amazon.smithy.build.FileManifest;
@@ -25,6 +26,7 @@
 import software.amazon.smithy.model.shapes.OperationShape;
 import software.amazon.smithy.model.shapes.ServiceShape;
 import software.amazon.smithy.model.traits.PaginatedTrait;
+import software.amazon.smithy.typescript.codegen.integration.TypeScriptIntegration;
 import software.amazon.smithy.waiters.WaitableTrait;
 import software.amazon.smithy.waiters.Waiter;
 
@@ -39,7 +41,8 @@ static void writeIndex(
         TypeScriptSettings settings,
         Model model,
         SymbolProvider symbolProvider,
-        FileManifest fileManifest
+        FileManifest fileManifest,
+        List<TypeScriptIntegration> integrations
     ) {
         TypeScriptWriter writer = new TypeScriptWriter("");
         ServiceShape service = settings.getService(model);
@@ -78,6 +81,10 @@ static void writeIndex(
 
         // write export statement for models
         writer.write("export * from \"./models/index\";");
+        // Write each custom export.
+        for (TypeScriptIntegration integration : integrations) {
+            integration.writeAdditionalExports(settings, model, symbolProvider, writer);
+        }
         fileManifest.writeFile("index.ts", writer.toString());
     }
 }

smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/integration/TypeScriptIntegration.java

@@ -160,6 +160,40 @@ default void writeAdditionalFiles(
         // pass
     }
 
+    /**
+     * Write additional export statement to client root index.ts.
+     * The files generated by {@link TypeScriptIntegration#writeAdditionalFiles}
+     * can be exported with this method.
+     *
+     * <pre>
+     * {@code
+     * public final class MyIntegration implements TypeScriptIntegration {
+     *     public writeAdditionalExports(
+     *             TypeScriptSettings settings,
+     *             Model model,
+     *             SymbolProvider symbolProvider,
+     *             TypeScriptWriter writer
+     *     ) {
+     *         writer.write("export * from $S;", "./foo.ts");
+     *     }
+     * }
+     * }</pre>
+     *
+     * @param settings Settings used to generate.
+     * @param model Model to generate from.
+     * @param symbolProvider Symbol provider used for codegen.
+     * @param writer TypeScript writer that works with the file.
+     * @see #writeAdditionalFiles(TypeScriptSettings, Model, SymbolProvider, BiConsumer)
+     */
+    default void writeAdditionalExports(
+            TypeScriptSettings settings,
+            Model model,
+            SymbolProvider symbolProvider,
+            TypeScriptWriter writer
+    ) {
+        // pass
+    }
+
     /**
      * Gets a list of plugins to apply to the generated client.
      *

smithy-typescript-codegen/src/test/java/software/amazon/smithy/typescript/codegen/IndexGeneratorTest.java

@@ -3,11 +3,14 @@
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.containsString;
 
+import java.util.ArrayList;
+import java.util.List;
 import org.junit.jupiter.api.Test;
 import software.amazon.smithy.build.MockManifest;
 import software.amazon.smithy.codegen.core.SymbolProvider;
 import software.amazon.smithy.model.Model;
 import software.amazon.smithy.model.node.Node;
+import software.amazon.smithy.typescript.codegen.integration.TypeScriptIntegration;
 
 public class IndexGeneratorTest {
 
@@ -21,13 +24,26 @@ public void writesIndex() {
                 .build());
         SymbolProvider symbolProvider = TypeScriptCodegenPlugin.createSymbolProvider(model, settings);
         MockManifest manifest = new MockManifest();
+        List<TypeScriptIntegration> integrations = new ArrayList<>();
+        integrations.add(new TypeScriptIntegration() {
+            @Override
+            public void writeAdditionalExports(
+                    TypeScriptSettings settings,
+                    Model model,
+                    SymbolProvider symbolProvider,
+                    TypeScriptWriter writer
+            ) {
+                writer.write("export * from $S;", "./foo");
+            }
+        });
 
-        IndexGenerator.writeIndex(settings, model, symbolProvider, manifest);
+        IndexGenerator.writeIndex(settings, model, symbolProvider, manifest, integrations);
 
         String contents = manifest.getFileString("index.ts").get();
         assertThat(contents, containsString("export * from \"./Example\";"));
         assertThat(contents, containsString("export * from \"./ExampleClient\";"));
         assertThat(contents, containsString("export * from \"./commands/GetFooCommand\";"));
         assertThat(contents, containsString("export * from \"./models/index\";"));
+        assertThat(contents, containsString("export * from \"./foo\";"));
     }
 }