feat: add experimental_readRawConfig() (#7573)

* add experimental_readRawConfig and tests

* move printBindings out of /config/index.ts

* fixups

* changeset

* actually export

Author: emily-shen

.changeset/blue-laws-bathe.md

@@ -0,0 +1,7 @@
+---
+"wrangler": patch
+---
+
+feat: add experimental_readRawConfig()
+
+Adds a Wrangler API to find and read a config file

packages/wrangler/docs/how-to/add-a-binding.md

@@ -7,7 +7,7 @@
    - `CfWorkerInit` in: `packages/wrangler/src/deployment-bundle/worker.ts` [ref](https://github.com/cloudflare/workers-sdk/blob/ce7db9d9cb4f5bcd5a326b86dde051cb54b999fb/packages/wrangler/src/deployment-bundle/worker.ts#L79C1-L85C2)
    - `WorkerMetadataBinding` in: `packages/wrangler/src/deployment-bundle/create-worker-upload-form.ts` [ref-1](https://github.com/cloudflare/workers-sdk/blob/ce7db9d9cb4f5bcd5a326b86dde051cb54b999fb/packages/wrangler/src/deployment-bundle/create-worker-upload-form.ts#L65) [ref-2](https://github.com/cloudflare/workers-sdk/blob/ce7db9d9cb4f5bcd5a326b86dde051cb54b999fb/packages/wrangler/src/deployment-bundle/create-worker-upload-form.ts#L219-L225)
 1. Add type to DevEnv `Binding` union in: `packages/wrangler/src/api/startDevWorker/types.ts` [ref](https://github.com/cloudflare/workers-sdk/blob/ce7db9d9cb4f5bcd5a326b86dde051cb54b999fb/packages/wrangler/src/api/startDevWorker/types.ts#L246)
-1. Add user-friendly output for `printBindings` in: `packages/wrangler/src/config/index.ts` [ref](https://github.com/cloudflare/workers-sdk/blob/ce7db9d9cb4f5bcd5a326b86dde051cb54b999fb/packages/wrangler/src/config/index.ts#L270-L280)
+1. Add user-friendly output for `printBindings` in: `packages/wrangler/src/utils/print-bindings.ts` [ref](https://github.com/cloudflare/workers-sdk/blob/ce7db9d9cb4f5bcd5a326b86dde051cb54b999fb/packages/wrangler/src/utils/print-bindings.ts)
 1. Add mapping functions to:
    - `createWorkerUploadForm` in: `packages/wrangler/src/deployment-bundle/create-worker-upload-form.ts` [ref](https://github.com/cloudflare/workers-sdk/blob/ce7db9d9cb4f5bcd5a326b86dde051cb54b999fb/packages/wrangler/src/deployment-bundle/create-worker-upload-form.ts#L219-L225)
    - `convertCfWorkerInitBindingstoBindings` in: `packages/wrangler/src/api/startDevWorker/utils.ts` [ref](https://github.com/cloudflare/workers-sdk/blob/ce7db9d9cb4f5bcd5a326b86dde051cb54b999fb/packages/wrangler/src/api/startDevWorker/utils.ts#L118-L123)

packages/wrangler/src/__tests__/configuration.test.ts

@@ -1,5 +1,6 @@
+import * as fs from "fs";
 import path from "node:path";
-import { readConfig } from "../config";
+import { experimental_readRawConfig, readConfig } from "../config";
 import { normalizeAndValidateConfig } from "../config/validation";
 import { run } from "../experimental-flags";
 import { normalizeString } from "./helpers/normalize";
@@ -6037,6 +6038,57 @@ describe("normalizeAndValidateConfig()", () => {
 	});
 });
 
+describe("experimental_readRawConfig()", () => {
+	describe.each(["json", "jsonc", "toml"])(
+		`with %s config files`,
+		(configType) => {
+			runInTempDir();
+			it(`should find a ${configType} config file given a specific path`, () => {
+				fs.mkdirSync("../folder", { recursive: true });
+				writeWranglerConfig({}, `../folder/config.${configType}`);
+
+				const result = experimental_readRawConfig({
+					config: `../folder/config.${configType}`,
+				});
+				expect(result.rawConfig).toEqual({
+					compatibility_date: "2022-01-12",
+					name: "test-name",
+				});
+			});
+
+			it("should find a config file given a specific script", () => {
+				fs.mkdirSync("./path/to", { recursive: true });
+				writeWranglerConfig(
+					{ name: "config-one" },
+					`./path/wrangler.${configType}`
+				);
+
+				fs.mkdirSync("../folder", { recursive: true });
+				writeWranglerConfig(
+					{ name: "config-two" },
+					`../folder/wrangler.${configType}`
+				);
+
+				let result = experimental_readRawConfig({
+					script: "./path/to/index.js",
+				});
+				expect(result.rawConfig).toEqual({
+					compatibility_date: "2022-01-12",
+					name: "config-one",
+				});
+
+				result = experimental_readRawConfig({
+					script: "../folder/index.js",
+				});
+				expect(result.rawConfig).toEqual({
+					compatibility_date: "2022-01-12",
+					name: "config-two",
+				});
+			});
+		}
+	);
+});
+
 function normalizePath(text: string): string {
 	return text
 		.replace("project\\wrangler.toml", "project/wrangler.toml")

packages/wrangler/src/api/startDevWorker/ConfigController.ts

@@ -10,7 +10,7 @@ import {
 	isLegacyEnv,
 } from "../..";
 import { getAssetsOptions, validateAssetsArgsAndConfig } from "../../assets";
-import { printBindings, readConfig } from "../../config";
+import { readConfig } from "../../config";
 import { getEntry } from "../../deployment-bundle/entry";
 import {
 	getBindings,
@@ -24,6 +24,7 @@ import { UserError } from "../../errors";
 import { logger } from "../../logger";
 import { requireApiToken, requireAuth } from "../../user";
 import { memoizeGetPort } from "../../utils/memoizeGetPort";
+import { printBindings } from "../../utils/print-bindings";
 import { getZoneIdForPreview } from "../../zones";
 import { Controller } from "./BaseController";
 import { castErrorCause } from "./events";

packages/wrangler/src/cli.ts

@@ -58,3 +58,5 @@ const generateASSETSBinding: (
 	// eslint-disable-next-line @typescript-eslint/no-var-requires
 	require("./miniflare-cli/assets").default;
 export { generateASSETSBinding as unstable_generateASSETSBinding };
+
+export { experimental_readRawConfig } from "./config";

packages/wrangler/src/config/config-helpers.ts

@@ -17,7 +17,6 @@ export function resolveWranglerConfigPath({
 	}
 
 	const leafPath = script !== undefined ? path.dirname(script) : process.cwd();
-
 	return findWranglerConfig(leafPath);
 }