feat: lazy evaluate InlineCode and show message before transforming (…

…#217)
mrgrain · Aug 14, 2022 · 98f7d1d · 98f7d1d
1 parent 1abd267
commit 98f7d1d
Show file tree

Hide file tree

Showing 3 changed files with 201 additions and 28 deletions.
diff --git a/API.md b/API.md
diff --git a/src/inline-code.ts b/src/inline-code.ts
@@ -1,4 +1,6 @@
-import { InlineCode } from 'aws-cdk-lib/aws-lambda';
+import { Lazy, Stack } from 'aws-cdk-lib';
+import { CodeConfig, InlineCode } from 'aws-cdk-lib/aws-lambda';
+import { Construct, Node } from 'constructs';
 import { TransformOptions, Loader } from './esbuild-types';
 import { transformSync, wrapWithEsbuildBinaryPath } from './esbuild-wrapper';
 
@@ -38,28 +40,45 @@ export interface TransformerProps {
 }
 
 abstract class BaseInlineCode extends InlineCode {
+  public readonly isInline = true;
+  private readonly inlineCode: string;
+
   public constructor(
     code: string,
     props: TransformerProps,
   ) {
+    super(code);
+
+    this.inlineCode = Lazy.string({
+      produce: () => {
+        try {
+          const {
+            transformFn = transformSync,
+            transformOptions = {},
+            esbuildBinaryPath,
+          } = props;
+
+          const transformedCode = wrapWithEsbuildBinaryPath(transformFn, esbuildBinaryPath)(code, {
+            color: process.env.NO_COLOR ? Boolean(process.env.NO_COLOR) : undefined,
+            logLevel: 'warning',
+            ...transformOptions,
+          });
+
+          return transformedCode.code;
+        } catch (error) {
+          throw new Error(`Failed to transform ${this.constructor.name}`);
+        }
+      },
+    });
+  }
+
+  public bind(scope: Construct): CodeConfig {
+    const name = scope.node.path + Node.PATH_SEP + this.constructor.name;
+    process.stderr.write(`Transforming inline code ${name}...\n`);
 
-    const {
-      transformFn = transformSync,
-      transformOptions = {},
-      esbuildBinaryPath,
-    } = props;
-
-    try {
-      const transformedCode = wrapWithEsbuildBinaryPath(transformFn, esbuildBinaryPath)(code, {
-        color: process.env.NO_COLOR ? Boolean(process.env.NO_COLOR) : undefined,
-        logLevel: 'warning',
-        ...transformOptions,
-      });
-
-      super(transformedCode.code);
-    } catch (error) {
-      throw new Error('Failed to transform InlineCode');
-    }
+    return {
+      inlineCode: Stack.of(scope).resolve(this.inlineCode),
+    };
   }
 }
 

diff --git a/test/inline-code.test.ts b/test/inline-code.test.ts
@@ -1,4 +1,5 @@
-import { Stack } from 'aws-cdk-lib';
+import { App, Stack } from 'aws-cdk-lib';
+import { Function, Runtime } from 'aws-cdk-lib/aws-lambda';
 import { mocked } from 'jest-mock';
 import { transformSync } from '../lib/esbuild-wrapper';
 import {
@@ -32,9 +33,10 @@ describe('using transformerProps', () => {
         "const banana = 'fruit' ?? 'vegetable'",
       );
 
-      const { inlineCode } = code.bind(new Stack());
+      const stack = new Stack();
+      const { inlineCode } = code.bind(stack);
 
-      expect(inlineCode).toBe('const banana = "fruit";\n');
+      expect(stack.resolve(inlineCode)).toBe('const banana = "fruit";\n');
     });
   });
 
@@ -60,6 +62,54 @@ describe('using transformerProps', () => {
 
       expect(inlineCode).toBe('let x = 1;\n');
     });
+
+    it('should announce the transforming step', () => {
+      const processStdErrWriteSpy = jest.spyOn(process.stderr, 'write');
+      const stack = new Stack(new App(), 'Stack');
+      const code = new InlineTypeScriptCode('let x: number = 1');
+
+      new Function(stack, 'MyFunction', {
+        runtime: Runtime.NODEJS_14_X,
+        handler: 'index.handler',
+        code,
+      });
+
+      expect(processStdErrWriteSpy).toHaveBeenCalledWith(
+        'Transforming inline code Stack/MyFunction/InlineTypeScriptCode...\n',
+      );
+      processStdErrWriteSpy.mockRestore();
+    });
+
+    it('should not do the work twice', () => {
+      const processStdErrWriteSpy = jest.spyOn(process.stderr, 'write');
+      const transformFn = jest.fn(transformSync);
+
+      const stack = new Stack(new App(), 'Stack');
+      const code = new InlineTypeScriptCode('let x: number = 1', {
+        transformFn,
+      });
+
+      new Function(stack, 'One', {
+        runtime: Runtime.NODEJS_14_X,
+        handler: 'index.handler',
+        code,
+      });
+
+      new Function(stack, 'Two', {
+        runtime: Runtime.NODEJS_14_X,
+        handler: 'index.handler',
+        code,
+      });
+
+      expect(transformFn).toHaveBeenCalledTimes(1);
+      expect(processStdErrWriteSpy).toHaveBeenCalledWith(
+        'Transforming inline code Stack/One/InlineTypeScriptCode...\n',
+      );
+      expect(processStdErrWriteSpy).toHaveBeenCalledWith(
+        'Transforming inline code Stack/Two/InlineTypeScriptCode...\n',
+      );
+      processStdErrWriteSpy.mockRestore();
+    });
   });
 
   describe('given some tsx code', () => {
@@ -81,23 +131,22 @@ describe('using transformerProps', () => {
       expect(() => {
         const code = new InlineTypeScriptCode('let : d ===== 1');
         code.bind(new Stack());
-      }).toThrowError('Failed to transform InlineCode');
+      }).toThrowError('Failed to transform InlineTypeScriptCode');
     });
 
     // Currently no way to capture esbuild output,
     // See https://github.com/evanw/esbuild/issues/2466
     it.skip('should display an error', () => {
-      const originalConsole = console.error;
-      console.error = jest.fn();
+      const processStdErrWriteSpy = jest.spyOn(process.stderr, 'write');
 
       expect(() => {
         const code = new InlineTypeScriptCode('let : d ===== 1');
         code.bind(new Stack());
-      }).toThrowError('Failed to transform InlineCode');
+      }).toThrowError('Failed to transform InlineTypeScriptCode');
 
-      expect(console.error).toBeCalledWith(expect.stringContaining('Unexpected "=="'));
+      expect(processStdErrWriteSpy).toBeCalledWith(expect.stringContaining('Unexpected "=="'));
 
-      console.error = originalConsole;
+      processStdErrWriteSpy.mockRestore();
     });
   });
 
@@ -149,10 +198,11 @@ describe('using transformerProps', () => {
         };
       };
 
-      new InlineTypeScriptCode('let x: number = 1', {
+      const code = new InlineTypeScriptCode('let x: number = 1', {
         transformFn: customTransform,
         esbuildBinaryPath: 'dummy-binary',
       });
+      code.bind(new Stack());
 
       expect(mockLogger).toHaveBeenCalledTimes(1);
       expect(mockLogger).toHaveBeenCalledWith('dummy-binary');