feat: Add ability to control bundling concurrency (#10)

Author: haroldadmin

package-lock.json

@@ -19,6 +19,7 @@
     "author": "Kshitij Chauhan",
     "license": "ISC",
     "dependencies": {
+        "@supercharge/promise-pool": "^2.1.0",
         "@types/command-line-args": "^5.0.0",
         "chalk": "^4.1.2",
         "command-line-args": "^5.1.1",

package.json

@@ -1,21 +1,28 @@
+import { PromisePool } from "@supercharge/promise-pool";
 import { build, BuildOptions } from "esbuild";
 import { err, ok, Result } from "neverthrow";
 import logger from "../logger";
 import { BundleResult } from "./bundleResult";
 
+export type BundlerConfig = BuildOptions & {
+    concurrency?: number;
+};
+
 export default async function bundleFunctions(
     functions: Record<string, string>,
-    bundlerConfig?: BuildOptions,
+    bundlerConfig?: BundlerConfig,
 ): Promise<Result<BundleResult[], Error>> {
-    try {
-        const bundlePromises = Object.entries(functions).map(([fxName, fxPath]) =>
-            bundleFunction(fxName, fxPath, bundlerConfig),
-        );
-        const bundleResults = await Promise.all(bundlePromises);
-        return ok(bundleResults);
-    } catch (error) {
-        return err(<Error>error);
+    const { concurrency = Object.keys(functions).length, ...config } = bundlerConfig ?? {};
+    console.log("Bundling with concurrency", concurrency);
+
+    const { errors, results } = await PromisePool.for(Object.entries(functions))
+        .withConcurrency(concurrency)
+        .process(([fxName, fxPath]) => bundleFunction(fxName, fxPath, config));
+    if (errors.length > 0) {
+        const [error] = errors;
+        return err(error);
     }
+    return ok(results);
 }
 
 export async function bundleFunction(
@@ -35,7 +42,6 @@ export async function bundleFunction(
         treeShaking: true,
         outdir: "bundled",
         ...bundlerConfig,
-        
         write: false,
     });
 

src/bundler/esbuild.ts

@@ -2,11 +2,12 @@
 
 import chalk from "chalk";
 import { bundleFunctions } from "./bundler";
+import { BundlerConfig } from "./bundler/esbuild";
 import hashesDiffer from "./differ/differ";
 import calculateHash from "./hasher/hasher";
 import segregate from "./hasher/segregate";
 import logger from "./logger";
-import { bundlerConfigFilePath, dir, prefix, separator, specFilePath, write } from "./options/options";
+import { bundlerConfigFilePath, concurrency, dir, prefix, separator, specFilePath, write } from "./options/options";
 import DifferSpec from "./parser/differSpec";
 import parseSpecFile, { parseBundlerConfigFile, resolveFunctionPaths } from "./parser/parser";
 import writeSpec from "./parser/writer";
@@ -24,7 +25,10 @@ async function main() {
         logger.error(bundlerConfigSpecResult.error);
         return;
     }
-    const bundlerConfig = bundlerConfigSpecResult.value;
+    const bundlerConfig: BundlerConfig = {
+        ...bundlerConfigSpecResult.value,
+        concurrency,
+    };
 
     const { functions, hashes: existingHashes } = specResult.value;
     logger.info(`Discovered ${Object.keys(functions).length} functions`);

src/index.ts

@@ -0,0 +1,11 @@
+import { expect } from "chai";
+import commandLineArgs from "command-line-args";
+import { options } from "./options";
+
+describe("options parsing", () => {
+    it("should parse concurrency arg correctly", () => {
+        const cmd = "functions-differ --concurrency 10";
+        const { concurrency } = commandLineArgs(options, { argv: cmd.split(" "), partial: true });
+        expect(concurrency).to.equal(10);
+    });
+});

src/options/options.spec.ts

@@ -1,17 +1,18 @@
 import cmdArgs, { OptionDefinition } from "command-line-args";
 import path from "path";
 
-const options: OptionDefinition[] = [
+export const options: OptionDefinition[] = [
     { name: "dir", alias: "d", type: String, defaultValue: process.cwd() },
     { name: "write", alias: "w", type: Boolean, defaultValue: true },
     { name: "verbose", alias: "v", type: Boolean, defaultValue: false },
     { name: "prefix", type: String, defaultValue: "functions:" },
     { name: "sep", type: String, defaultValue: "," },
-    { name: "bundlerConfig", type: String, defaultValue: "" }
+    { name: "bundlerConfig", type: String, defaultValue: "" },
+    { name: "concurrency", type: Number },
 ];
 
 const args = cmdArgs(options, { partial: true });
-const { dir, write, verbose, prefix, sep: separator, bundlerConfig } = args;
+const { dir, write, verbose, prefix, sep: separator, bundlerConfig, concurrency } = args;
 if (!dir) {
     console.error("Error: dir argument not supplied");
     process.exit(1);
@@ -20,4 +21,4 @@ if (!dir) {
 const specFilePath: string = path.join(dir, ".differspec.json");
 const bundlerConfigFilePath: string = bundlerConfig ? path.join(dir, bundlerConfig) : "";
 
-export { specFilePath, dir, write, verbose, prefix, separator, bundlerConfigFilePath };
+export { specFilePath, dir, write, verbose, prefix, separator, bundlerConfigFilePath, concurrency };