fix(aws-ssm): correctly emit Association.Name

The rename used to happen in the cfnspec, which helped the model
generate correct names, but the code generator would lose the ability to
access the original name, and so it could not be emitted correctly.

Add a property renaming feature to the 'cfn2ts' code generator
(configured via a special entry in package.json).

Fixes #852.

packages/@aws-cdk/aws-ssm/package.json

@@ -39,6 +39,11 @@
   "cdk-build": {
     "cloudformation": "AWS::SSM"
   },
+  "cfn2ts": {
+    "rename": {
+      "AWS::SSM::Association/Name": "DocumentName"
+    }
+  },
   "keywords": [
     "aws",
     "cdk",

tools/cfn2ts/lib/codegen.ts

@@ -24,7 +24,7 @@ export default class CodeGenerator {
    * @param moduleName the name of the module (used to determine the file name).
    * @param spec     CloudFormation resource specification
    */
-  constructor(moduleName: string, private readonly spec: schema.Specification) {
+  constructor(moduleName: string, private readonly spec: schema.Specification, private readonly renames: {[key: string]: string}) {
     this.outputFile = `${moduleName}.generated.ts`;
     this.code.openFile(this.outputFile);
 
@@ -117,23 +117,26 @@ export default class CodeGenerator {
     this.code.closeBlock();
   }
 
-  private emitPropsType(resourceName: genspec.CodeName, spec: schema.ResourceType): genspec.CodeName | undefined {
-    if (!spec.Properties || Object.keys(spec.Properties).length === 0) { return; }
-    const name = genspec.CodeName.forResourceProperties(resourceName);
+  /**
+   * Emit the XxxProps interface for a resource
+   */
+  private emitPropsType(resourceName: genspec.CodeName, spec: schema.ResourceType): PropsInterfaceType {
+    if (!spec.Properties || Object.keys(spec.Properties).length === 0) { return { attributesTable: {}}; }
+    const codeName = genspec.CodeName.forResourceProperties(resourceName);
 
     this.docLink(spec.Documentation);
-    this.code.openBlock(`export interface ${name.className}`);
+    this.code.openBlock(`export interface ${codeName.className}`);
 
-    const conversionTable = this.emitPropsTypeProperties(resourceName.specName!, spec.Properties);
+    const attributesTable = this.emitPropsTypeProperties(resourceName.specName!, spec.Properties);
 
     this.code.closeBlock();
 
     this.code.line();
-    this.emitValidator(name, spec.Properties, conversionTable);
+    this.emitValidator(codeName, spec.Properties, attributesTable);
     this.code.line();
-    this.emitCloudFormationMapper(name, spec.Properties, conversionTable);
+    this.emitCloudFormationMapper(codeName, spec.Properties, attributesTable);
 
-    return name;
+    return { codeName, attributesTable };
   }
 
   /**
@@ -143,28 +146,37 @@ export default class CodeGenerator {
    */
   private emitPropsTypeProperties(resourceName: SpecName, propertiesSpec: { [name: string]: schema.Property }): Dictionary<string> {
     const propertyMap: Dictionary<string> = {};
-
-    // Sanity check that our renamed "Name" is not going to conflict with a real property
-    const renamedNameProperty = resourceNameProperty(resourceName);
-    const lowerNames = Object.keys(propertiesSpec).map(s => s.toLowerCase());
-    if (lowerNames.indexOf('name') !== -1 && lowerNames.indexOf(renamedNameProperty.toLowerCase()) !== -1) {
-      // tslint:disable-next-line:max-line-length
-      throw new Error(`Oh gosh, we want to rename ${resourceName.fqn}'s 'Name' property to '${renamedNameProperty}', but that property already exists! We need to find a solution to this problem.`);
-    }
+    const finalNames = new Set<string>();
 
     Object.keys(propertiesSpec).sort(propertyComparator).forEach(propName => {
       const originalName = propName;
       const propSpec = propertiesSpec[propName];
       const additionalDocs = resourceName.relativeName(propName).fqn;
 
+      // Apply property renames
+      const renameKey = `${resourceName.fqn}/${propName}`;
+      if (renameKey in this.renames) {
+        // User-defined rename
+        propName = this.renames[renameKey];
+      }
+
       if (propName.toLocaleLowerCase() === 'name') {
-        propName = renamedNameProperty;
+        // We like to include the resource name in the "name" property
+        propName = resourceNameProperty(resourceName);
+      }
+
+      if (originalName !== propName) {
         // tslint:disable-next-line:no-console
-        console.error(`Renamed property 'Name' of ${resourceName.fqn} to '${renamedNameProperty}'`);
+        console.error(`[${resourceName.fqn}] Renamed property '${originalName}' to '${propName}'`);
       }
+      if (finalNames.has(propName)) {
+        throw new Error(`Oh gosh, there was already a property named ${propName}!`);
+      }
+      finalNames.add(propName);
 
       const resourceCodeName = genspec.CodeName.forResource(resourceName);
       const newName = this.emitProperty(resourceCodeName, propName, propSpec, quoteCode(additionalDocs));
+
       propertyMap[originalName] = newName;
     });
     return propertyMap;
@@ -265,16 +277,16 @@ export default class CodeGenerator {
     this.code.line(` * @param properties the properties of this ${quoteCode(resourceName.className)}`);
     this.code.line(' */');
     const optionalProps = spec.Properties && !Object.values(spec.Properties).some(p => p.Required);
-    const propsArgument = propsType ? `, properties${optionalProps ? '?' : ''}: ${propsType.className}` : '';
+    const propsArgument = propsType.codeName ? `, properties${optionalProps ? '?' : ''}: ${propsType.codeName.className}` : '';
     this.code.openBlock(`constructor(parent: ${CONSTRUCT_CLASS}, name: string${propsArgument})`);
     this.code.line(`super(parent, name, { type: ${resourceName.className}.resourceTypeName${propsType ? ', properties' : ''} });`);
     // verify all required properties
     if (spec.Properties) {
       for (const pname of Object.keys(spec.Properties)) {
         const prop = spec.Properties[pname];
         if (prop.Required) {
-          const propName = pname.toLocaleLowerCase() === 'name' ? resourceNameProperty(resourceName.specName!) : pname;
-          this.code.line(`${CORE}.requireProperty(properties, '${genspec.cloudFormationToScriptName(propName)}', this);`);
+          const attributeName = propsType.attributesTable[pname];
+          this.code.line(`${CORE}.requireProperty(properties, '${genspec.cloudFormationToScriptName(attributeName)}', this);`);
         }
       }
     }
@@ -304,9 +316,9 @@ export default class CodeGenerator {
 
     this.code.closeBlock();
 
-    if (propsType) {
+    if (propsType.codeName) {
       this.code.line();
-      this.emitCloudFormationPropertiesOverride(propsType);
+      this.emitCloudFormationPropertiesOverride(propsType.codeName);
     }
 
     this.closeClass(resourceName);
@@ -619,6 +631,25 @@ export default class CodeGenerator {
   }
 }
 
+/**
+ * Represents a PropsType that has been generated
+ */
+interface PropsInterfaceType {
+  /**
+   * Name in the code of the XxxProps type
+   *
+   * Missing if no type got generated because there were no properties.
+   */
+  codeName?: genspec.CodeName;
+
+  /**
+   * Name conversion table for properties on this props type
+   *
+   * Maps cfn name -> attribute name.
+   */
+  attributesTable: Dictionary<string>;
+}
+
 /**
  * Return a comma-separated list of validator functions for the given types
  */

tools/cfn2ts/lib/index.ts

@@ -14,7 +14,23 @@ export default async function(scope: string, outPath: string, force: boolean) {
   }
   const name = packageName(scope);
 
-  const generator = new CodeGenerator(name, spec);
+  // Read package.json in the current directory to determine renames
+  const renames: {[key: string]: string} = {};
+  let packageJson;
+  try {
+    packageJson = require(path.resolve(process.cwd(), 'package.json'));
+  } catch (e) {
+    // Nothing
+  }
+  if (packageJson && packageJson.cfn2ts && packageJson.cfn2ts.rename) {
+    // tslint:disable-next-line:no-console
+    console.error('Reading renames from package.json');
+    for (const [key, value] of Object.entries(packageJson.cfn2ts.rename)) {
+      renames[key] = value as any;
+    }
+  }
+
+  const generator = new CodeGenerator(name, spec, renames);
 
   if (!force && await generator.upToDate(outPath)) {
     // tslint:disable-next-line:no-console