batch.ts

import {
  AwsOptions,
  CommonOptions,
  faastAws,
  faastLocal,
  FaastModuleProxy,
  LocalOptions,
  log,
} from "faastjs";
import mergeOptions from "merge-options";
import semver from "semver";
import { assertNonNullable } from "./assert";
import * as compilerFaastFunctions from "./compiler-core";
import { DuckConfig } from "./duckconfig";
import { logger } from "./logger";

// change to stdout
log.info.log = console.log.bind(console);

export async function getFaastCompiler(
  config: DuckConfig
): Promise<FaastModuleProxy<typeof compilerFaastFunctions, CommonOptions, any>> {
  logger.info("Initializing batch mode");
  const batch = assertNonNullable(config.batch);
  const batchOptions = getBatchOptions(config);
  const m =
    batch === "aws"
      ? await faastAws(compilerFaastFunctions, batchOptions as AwsOptions)
      : batch === "local"
      ? await faastLocal(compilerFaastFunctions, batchOptions as LocalOptions)
      : null;
  if (!m) {
    throw new TypeError(`Unsupported batch mode: ${batch}`);
  }
  return m;
}

function getBatchOptions(config: DuckConfig): AwsOptions | LocalOptions {
  const { batchOptions = {} } = config;
  return mergeOptions.call({ concatArrays: true }, defaultBatchOptions(config), batchOptions);
}

function defaultBatchOptions(config: DuckConfig): AwsOptions {
  const closureVersion = require("google-closure-compiler/package.json").version;
  const major = semver.major(closureVersion);
  return {
    packageJson: {
      // To suppress npm warnings
      private: true,
      dependencies: {
        [`google-closure-compiler-${getOsForNativeImage(config)}`]: `^${major}.0.0`,
      },
    },
    webpackOptions: {
      externals: [
        /^aws-sdk\/?/,
        "google-closure-compiler-js",
        "google-closure-compiler-linux",
        "google-closure-compiler-osx",
        // used in google-closure-compiler/lib/(grunt|gulp)
        "chalk",
        // used in google-closure-compiler/lib/gulp
        /^gulp($|-)/,
        /^vinyl($|-)/,
      ],
    },
  };
}

function getOsForNativeImage(config: DuckConfig) {
  const { platform } = process;
  if (config.batch === "aws" || platform === "linux") {
    return "linux";
  } else if (platform === "darwin") {
    return "osx";
  } else {
    throw new Error(`Unsuported Platform: ${platform}`);
  }
}