Merge pull request #1350 from spotify/rugvip/confkeys

packages/config: added .keys()

packages/config/src/reader.test.ts

@@ -37,6 +37,7 @@ const DATA = {
 };
 
 function expectValidValues(config: ConfigReader) {
+  expect(config.keys()).toEqual(Object.keys(DATA));
   expect(config.getNumber('zero')).toBe(0);
   expect(config.getNumber('one')).toBe(1);
   expect(config.getBoolean('true')).toBe(true);
@@ -111,6 +112,7 @@ function expectInvalidValues(config: ConfigReader) {
 describe('ConfigReader', () => {
   it('should read empty config with valid keys', () => {
     const config = new ConfigReader({});
+    expect(config.keys()).toEqual([]);
     expect(config.getOptionalString('x')).toBeUndefined();
     expect(config.getOptionalString('x_x')).toBeUndefined();
     expect(config.getOptionalString('x-X')).toBeUndefined();
@@ -208,6 +210,17 @@ describe('ConfigReader with fallback', () => {
 
     const config = new ConfigReader(a, new ConfigReader(b));
 
+    expect(config.keys()).toEqual(['merged']);
+    expect(config.getConfig('merged').keys()).toEqual([
+      'x',
+      'z',
+      'arr',
+      'config',
+      'configs',
+      'y',
+    ]);
+    expect(config.getConfig('merged.config').keys()).toEqual(['d', 'e']);
+
     expect(config.getString('merged.x')).toBe('x');
     expect(config.getString('merged.y')).toBe('y');
     expect(config.getString('merged.z')).toBe('z1');

packages/config/src/reader.ts

@@ -68,6 +68,12 @@ export class ConfigReader implements Config {
     private readonly prefix: string = '',
   ) {}
 
+  keys(): string[] {
+    const localKeys = this.data ? Object.keys(this.data) : [];
+    const fallbackKeys = this.fallback?.keys() ?? [];
+    return [...new Set([...localKeys, ...fallbackKeys])];
+  }
+
   getConfig(key: string): ConfigReader {
     const value = this.readValue(key);
     const fallbackConfig = this.fallback?.getConfig(key);

packages/config/src/types.ts

@@ -27,6 +27,8 @@ export type JsonValue =
 export type AppConfig = JsonObject;
 
 export type Config = {
+  keys(): string[];
+
   getConfig(key: string): Config;
 
   getConfigArray(key: string): Config[];