preinstall.js

   1 "use strict";
   2
   3 const fs = require("fs");
   4 const path = require("path");
   5
   6 const { https } = require("follow-redirects");
   7 const tar = require("tar");
   8 const unbz2 = require("unbzip2-stream");
   9 const unzipper = require("unzipper");
  10
  11 const pkg = require("./package.json");
  12 const bindir = path.join(__dirname, "bin");
  13
  14 const trim = str => str && String(str).trim();
  15
  16 const dhallVersion = trim(pkg["dhall-version"] || process.env.DHALL_VERSION);
  17 if (!dhallVersion) throw new Error("Missing DHALL_VERSION environment variable.");
  18
  19 const dhallJsonVersion = trim(pkg["dhall-json-version"] || process.env.DHALL_JSON_VERSION);
  20 if (!dhallJsonVersion) throw new Error("Missing DHALL_JSON_VERSION environment variable.");
  21
  22 const release = `https://github.com/dhall-lang/dhall-haskell/releases/download/${dhallVersion}/dhall-json-${dhallJsonVersion}`;
  23
  24 const get = (archive, callback) => {
  25   const url = `${release}-${archive}`;
  26   return https.get(url, res => {
  27     if (res.statusCode >= 400) throw new Error(`Error fetching ${url}: ${res.statusMessage}`);
  28     return callback(res);
  29   });
  30 };
  31
  32 if (process.platform === "win32") {
  33   get("x86_64-windows.zip", res =>
  34     res.pipe(unzipper.Extract({ path: bindir }))
  35   );
  36 } else {
  37   get("x86_64-linux.tar.bz2", res =>
  38     res.pipe(unbz2()).pipe(tar.x({ C: __dirname }).on("finish", () => {
  39       fs.readdir(bindir, (err, names) => {
  40         if (err) throw err;
  41         for (const name of names) {
  42           fs.rename(path.join(bindir, name), path.join(bindir, name + ".exe"), err => {
  43             if (err) throw err;
  44           });
  45         }
  46       });
  47     }))
  48   );
  49 }