feat: getOptions util for loader

lib/NormalModule.js

@@ -5,7 +5,10 @@
 
 "use strict";
 
+const parseJson = require("json-parse-better-errors");
 const { getContext, runLoaders } = require("loader-runner");
+const querystring = require("querystring");
+const validateOptions = require("schema-utils");
 const { SyncHook } = require("tapable");
 const {
 	CachedSource,
@@ -350,6 +353,50 @@ class NormalModule extends Module {
 		};
 		const loaderContext = {
 			version: 2,
+			getOptions: (loaderName, schema) => {
+				const loader = loaderContext.loaders[loaderContext.loaderIndex];
+				let options = {};
+
+				if (loader.options && typeof loader.options === "object") {
+					({ options } = loader);
+				} else if (loader.query) {
+					let { query } = loader;
+
+					if (query.substr(0, 1) !== "?") {
+						throw new WebpackError(
+							"A valid query string should begin with '?'"
+						);
+					}
+
+					query = query.substr(1);
+
+					// Allow to use `?foo=bar` in `options`
+					if (query.substr(0, 1) === "?") {
+						query = query.substr(1);
+					}
+
+					if (query.substr(0, 1) === "{" && query.substr(-1) === "}") {
+						try {
+							options = parseJson(query);
+						} catch (e) {
+							throw new WebpackError(`Cannot parse query string: ${e.message}`);
+						}
+					} else {
+						options = querystring.parse(query);
+					}
+				}
+
+				if (!schema) {
+					return options;
+				}
+
+				validateOptions(schema, options, {
+					name: loaderName || "Unknown Loader",
+					baseDataPath: "options"
+				});
+
+				return options;
+			},
 			emitWarning: warning => {
 				if (!(warning instanceof Error)) {
 					warning = new NonErrorEmittedError(warning);

test/configCases/loaders/options/index.js

@@ -0,0 +1,45 @@
+it("should get options", function() {
+	expect(require("./a")).toStrictEqual({
+		arg: true,
+		arg1: null,
+		arg3: 1234567890,
+		arg4: "string",
+		arg5: [1, 2, 3],
+		arg6: { foo: "value", bar: { baz: "other-value" } }
+	});
+	expect(require("./b")).toStrictEqual({
+		arg: true,
+		arg1: null,
+		arg3: 1234567890,
+		arg4: "string",
+		arg5: [1, 2, 3],
+		arg6: { foo: "value", bar: { baz: "other-value" } }
+	});
+	expect(require("./c")).toStrictEqual({
+		arg: true,
+		arg1: null,
+		arg3: 1234567890,
+		arg4: "string",
+		arg5: [1, 2, 3],
+		arg6: { foo: "value", bar: { baz: "other-value" } }
+	});
+	expect(require("./d")).toStrictEqual({
+		arg4: "text"
+	});
+	expect(require("./e")).toStrictEqual({});
+	expect(require("./f")).toStrictEqual({
+		delicious: "",
+		name: "cheesecake",
+		slices: "8",
+		warm: "false"
+	});
+	expect(require("./g")).toStrictEqual({
+		"=": "="
+	});
+	expect(require("./h")).toStrictEqual({
+		"foo": "bar"
+	});
+	expect(require("./i")).toStrictEqual({
+		"foo": "bar"
+	});
+});

test/configCases/loaders/options/loader-1.js

@@ -0,0 +1,12 @@
+const schema = require('./loader-1.options');
+
+module.exports = function() {
+	const options = this.getOptions('Loader Name', schema);
+
+	const json = JSON.stringify(options)
+		.replace(/\u2028/g, '\\u2028')
+		.replace(/\u2029/g, '\\u2029');
+
+
+	return `module.exports = ${json}`;
+};

test/configCases/loaders/options/loader-1.options.json

@@ -0,0 +1,43 @@
+{
+  "additionalProperties": false,
+  "properties": {
+    "arg": {
+      "type": "boolean"
+    },
+    "arg1": {
+      "type": "null"
+    },
+    "arg2": {},
+    "arg3": {
+      "type": "number"
+    },
+    "arg4": {
+      "type": "string"
+    },
+    "arg5": {
+      "type": "array",
+      "items": {
+        "type": "number"
+      }
+    },
+    "arg6": {
+      "type": "object",
+      "properties": {
+        "foo": {
+          "type": "string"
+        },
+        "bar": {
+          "type": "object",
+          "properties": {
+            "baz": {
+              "type": "string"
+            }
+          },
+          "additionalProperties": false
+        }
+      },
+      "additionalProperties": false
+    }
+  },
+  "type": "object"
+}

test/configCases/loaders/options/loader.js

@@ -0,0 +1,9 @@
+module.exports = function() {
+	const options = this.getOptions();
+
+	const json = JSON.stringify(options)
+		.replace(/\u2028/g, '\\u2028')
+		.replace(/\u2029/g, '\\u2029');
+
+	return `module.exports = ${json}`;
+};

test/configCases/loaders/options/webpack.config.js

@@ -0,0 +1,78 @@
+module.exports = {
+	mode: "none",
+	module: {
+		rules: [
+			{
+				test: /a\.js$/,
+				loader: "./loader",
+				options: {
+					arg: true,
+					arg1: null,
+					arg2: undefined,
+					arg3: 1234567890,
+					arg4: "string",
+					arg5: [1, 2, 3],
+					arg6: { foo: "value", bar: { baz: "other-value" } }
+				}
+			},
+			{
+				test: /b\.js$/,
+				loader: "./loader-1",
+				options: {
+					arg: true,
+					arg1: null,
+					arg2: undefined,
+					arg3: 1234567890,
+					arg4: "string",
+					arg5: [1, 2, 3],
+					arg6: { foo: "value", bar: { baz: "other-value" } }
+				}
+			},
+			{
+				test: /c\.js$/,
+				loader: "./loader-1",
+				options: JSON.stringify({
+					arg: true,
+					arg1: null,
+					arg2: undefined,
+					arg3: 1234567890,
+					arg4: "string",
+					arg5: [1, 2, 3],
+					arg6: { foo: "value", bar: { baz: "other-value" } }
+				})
+			},
+			{
+				test: /d\.js$/,
+				loader: "./loader-1",
+				options: "arg4=text"
+			},
+			{
+				test: /d\.js$/,
+				loader: "./loader",
+				options: "?"
+			},
+			{
+				test: /f\.js$/,
+				loader: "./loader",
+				options: "name=cheesecake&slices=8&delicious&warm=false"
+			},
+			{
+				test: /g\.js$/,
+				loader: "./loader",
+				options: "%3d=%3D"
+			},
+			{
+				test: /h\.js$/,
+				loader: "./loader",
+				options: "?foo=bar"
+			},
+			{
+				test: /i\.js$/,
+				loader: "./loader",
+				options: `?${JSON.stringify({
+					foo: "bar"
+				})}`
+			}
+		]
+	}
+};