feat: adds @app-config/extension-utils package, simplifying extension logic

Author: joelgallant

.github/workflows/publishing.yml

@@ -46,6 +46,11 @@ jobs:
         token: ${{ secrets.NPM_TOKEN }}
         access: public
         package: ./app-config-encryption/package.json
+    - uses: JS-DevTools/npm-publish@v1
+      with:
+        token: ${{ secrets.NPM_TOKEN }}
+        access: public
+        package: ./app-config-extension-utils/package.json
     - uses: JS-DevTools/npm-publish@v1
       with:
         token: ${{ secrets.NPM_TOKEN }}

app-config-extension-utils/.eslintrc.js

@@ -0,0 +1 @@
+module.exports = require('@lcdev/eslint-config/cwd')(__dirname);

app-config-extension-utils/README.md

@@ -0,0 +1,40 @@
+{
+  "name": "@app-config/extension-utils",
+  "description": "Utilities for writing @app-config parsing extensions",
+  "version": "2.1.5",
+  "license": "MPL-2.0",
+  "author": {
+    "name": "Launchcode",
+    "email": "[email protected]",
+    "url": "https://lc.dev"
+  },
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/launchcodedev/app-config.git"
+  },
+  "main": "dist/index.js",
+  "module": "dist/es/index.js",
+  "types": "dist/index.d.ts",
+  "files": [
+    "/dist",
+    "!**/*.tsbuildinfo",
+    "!**/*.test.*"
+  ],
+  "scripts": {
+    "build": "tsc -b",
+    "build:es": "tsc -b tsconfig.es.json",
+    "clean": "rm -rf dist *.tsbuildinfo",
+    "lint": "eslint src",
+    "fix": "eslint --fix src",
+    "test": "jest",
+    "prepublishOnly": "yarn clean && yarn build && yarn build:es"
+  },
+  "dependencies": {
+    "@app-config/core": "^2.1.5"
+  },
+  "devDependencies": {},
+  "prettier": "@lcdev/prettier",
+  "jest": {
+    "preset": "@lcdev/jest"
+  }
+}

app-config-extension-utils/package.json

@@ -0,0 +1,88 @@
+import { LiteralSource } from '@app-config/core';
+import { forKey, composeExtensions } from './index';
+
+const foo = forKey('$foo', () => (parse) => parse('foo!'));
+const bar = forKey('$bar', () => (parse) => parse('bar!'));
+const plusOne = forKey(['+1', '$plusOne'], (value) => (parse) =>
+  parse((value as number) + 1, { shouldFlatten: true }),
+);
+
+describe('forKey', () => {
+  it('only applies for keys given', async () => {
+    const source = {
+      a: {
+        b: {
+          $plusOne: 33,
+        },
+        c: {
+          '+1': 1,
+        },
+        d: {
+          $foo: 'bar',
+        },
+      },
+    };
+
+    expect(await new LiteralSource(source).readToJSON([foo, bar, plusOne])).toEqual({
+      a: {
+        b: 34,
+        c: 2,
+        d: {
+          $foo: 'foo!',
+        },
+      },
+    });
+  });
+});
+
+describe('composeExtensions', () => {
+  it('combines two extensions', async () => {
+    const source = {
+      $foo: 1,
+      $bar: 2,
+    };
+
+    expect(await new LiteralSource(source).readToJSON([foo, bar])).toEqual({
+      $foo: 'foo!',
+      $bar: 'bar!',
+    });
+
+    const combined = composeExtensions([foo, bar]);
+
+    expect(await new LiteralSource(source).readToJSON([combined])).toEqual({
+      $foo: 'foo!',
+      $bar: 'bar!',
+    });
+  });
+
+  it('combines two extensions, and applies them in nested properties', async () => {
+    const source = {
+      $foo: 1,
+      a: {
+        b: {
+          $bar: 2,
+        },
+      },
+    };
+
+    expect(await new LiteralSource(source).readToJSON([foo, bar])).toEqual({
+      $foo: 'foo!',
+      a: {
+        b: {
+          $bar: 'bar!',
+        },
+      },
+    });
+
+    const combined = composeExtensions([foo, bar]);
+
+    expect(await new LiteralSource(source).readToJSON([combined])).toEqual({
+      $foo: 'foo!',
+      a: {
+        b: {
+          $bar: 'bar!',
+        },
+      },
+    });
+  });
+});

app-config-extension-utils/src/index.test.ts

@@ -0,0 +1,33 @@
+import type { ParsingExtension, ParsingExtensionKey } from '@app-config/core';
+import { parseValue, Root } from '@app-config/core';
+
+export function forKey(
+  key: string | string[],
+  parsingExtension: ParsingExtension,
+): ParsingExtension {
+  const shouldApply = ([_, k]: ParsingExtensionKey) => {
+    if (typeof k !== 'string') return false;
+
+    if (Array.isArray(key)) {
+      return key.includes(k);
+    }
+
+    return key === k;
+  };
+
+  return (value, ctxKey, ctx) => {
+    if (shouldApply(ctxKey)) {
+      return parsingExtension(value, ctxKey, ctx);
+    }
+
+    return false;
+  };
+}
+
+export function composeExtensions(extensions: ParsingExtension[]): ParsingExtension {
+  return (value, [k]) => {
+    if (k !== Root) return false;
+
+    return (_, __, source) => parseValue(value, source, extensions, { shouldFlatten: true });
+  };
+}

app-config-extension-utils/src/index.ts

@@ -0,0 +1,8 @@
+{
+  "extends": "./tsconfig.json",
+  "compilerOptions": {
+    "target": "es2020",
+    "module": "es2020",
+    "outDir": "./dist/es"
+  }
+}

app-config-extension-utils/tsconfig.es.json

@@ -0,0 +1,12 @@
+{
+  "extends": "@lcdev/tsconfig",
+  "compilerOptions": {
+    "rootDir": "./src",
+    "outDir": "./dist"
+  },
+  "include": ["src"],
+  "exclude": ["node_modules"],
+  "references": [
+    { "path": "../app-config-core" }
+  ]
+}

app-config-extension-utils/tsconfig.json

@@ -31,6 +31,7 @@
   },
   "dependencies": {
     "@app-config/core": "^2.1.5",
+    "@app-config/extension-utils": "^2.1.5",
     "@app-config/logging": "^2.1.5",
     "@app-config/node": "^2.1.5",
     "@app-config/utils": "^2.1.5"