feat(@angular-devkit/schematics-cli): add prompt support using Inquirer

packages/angular_devkit/schematics_cli/BUILD

@@ -31,6 +31,7 @@ ts_library(
         "//packages/angular_devkit/schematics:tools",
         "@rxjs",
         "@rxjs//operators",
+        "@npm//@types/inquirer",
         "@npm//@types/minimist",
         "@npm//@types/node",
     ],

packages/angular_devkit/schematics_cli/bin/schematics.ts

@@ -12,7 +12,9 @@ import 'symbol-observable';
 // tslint:disable-next-line:ordered-imports import-groups
 import {
   JsonObject,
+  logging,
   normalize,
+  schema,
   tags,
   terminal,
   virtualFs,
@@ -24,6 +26,7 @@ import {
   UnsuccessfulWorkflowExecution,
 } from '@angular-devkit/schematics';
 import { NodeModulesEngineHost, NodeWorkflow } from '@angular-devkit/schematics/tools';
+import * as inquirer from 'inquirer';
 import * as minimist from 'minimist';
 
 
@@ -59,12 +62,68 @@ export interface MainOptions {
   stderr?: ProcessOutput;
 }
 
+
+function _listSchematics(collectionName: string, logger: logging.Logger) {
+  try {
+    const engineHost = new NodeModulesEngineHost();
+    const engine = new SchematicEngine(engineHost);
+    const collection = engine.createCollection(collectionName);
+    logger.info(engine.listSchematicNames(collection).join('\n'));
+  } catch (error) {
+    logger.fatal(error.message);
+
+    return 1;
+  }
+
+  return 0;
+}
+
+function _createPromptProvider(): schema.PromptProvider {
+  return (definitions: Array<schema.PromptDefinition>) => {
+    const questions: inquirer.Questions = definitions.map(definition => {
+      const question: inquirer.Question = {
+        name: definition.id,
+        message: definition.message,
+        default: definition.default,
+      };
+
+      const validator = definition.validator;
+      if (validator) {
+        question.validate = input => validator(input);
+      }
+
+      switch (definition.type) {
+        case 'confirmation':
+          return { ...question, type: 'confirm' };
+        case 'list':
+          return {
+            ...question,
+            type: 'list',
+            choices: definition.items && definition.items.map(item => {
+              if (typeof item == 'string') {
+                return item;
+              } else {
+                return {
+                  name: item.label,
+                  value: item.value,
+                };
+              }
+            }),
+          };
+        default:
+          return { ...question, type: definition.type };
+      }
+    });
+
+    return inquirer.prompt(questions);
+  };
+}
+
 export async function main({
   args,
   stdout = process.stdout,
   stderr = process.stderr,
 }: MainOptions): Promise<0 | 1> {
-
   const argv = parseArgs(args);
 
   /** Create the DevKit Logger used through the CLI. */
@@ -84,18 +143,7 @@ export async function main({
 
   /** If the user wants to list schematics, we simply show all the schematic names. */
   if (argv['list-schematics']) {
-    try {
-      const engineHost = new NodeModulesEngineHost();
-      const engine = new SchematicEngine(engineHost);
-      const collection = engine.createCollection(collectionName);
-      logger.info(engine.listSchematicNames(collection).join('\n'));
-    } catch (error) {
-      logger.fatal(error.message);
-
-      return 1;
-    }
-
-    return 0;
+    return _listSchematics(collectionName, logger);
   }
 
   if (!schematicName) {
@@ -208,6 +256,9 @@ export async function main({
   });
   delete parsedArgs._;
 
+  // Add prompts.
+  workflow.registry.usePromptProvider(_createPromptProvider());
+
 
   /**
    *  Execute the workflow, which will report the dry run events, run the tasks, and complete

packages/angular_devkit/schematics_cli/package.json

@@ -17,8 +17,9 @@
     "@angular-devkit/core": "0.0.0",
     "@angular-devkit/schematics": "0.0.0",
     "@schematics/schematics": "0.0.0",
+    "inquirer": "6.2.0",
     "minimist": "1.2.0",
-    "symbol-observable": "1.2.0",
-    "rxjs": "6.3.3"
+    "rxjs": "6.3.3",
+    "symbol-observable": "1.2.0"
   }
 }