feat: stream zip files to destination binary

src/compiler.ts

@@ -16,9 +16,11 @@ import {
 } from './util'
 import { NexeOptions, version } from './options'
 import { NexeTarget } from './target'
+import { PassThrough, Readable, Stream, Transform } from 'stream'
 import MultiStream = require('multistream')
 import { Bundle, toStream } from './fs/bundle'
 import { File } from 'resolve-dependencies'
+import { FactoryStream, LazyStream } from 'multistream'
 
 const isBsd = Boolean(~process.platform.indexOf('bsd'))
 const make = isWindows ? 'vcbuild.bat' : isBsd ? 'gmake' : 'make'
@@ -287,25 +289,34 @@ export class NexeCompiler {
     return [this.shims.join(''), this.startup].join(';')
   }
 
-  private async _assembleDeliverable(binary: NodeJS.ReadableStream) {
+  private async _assembleDeliverable(binary: Readable) {
     if (!this.options.mangle) {
       return binary
     }
+    const launchCode = this.code()
+    const vfsStream = await this.bundle.toStream()
+    let vfsSize = 0
+    const vfsSum = new Transform({
+      transform(chunk, _enc, cb) {
+        chunk && (vfsSize += chunk.length)
+        cb(null, chunk)
+      },
+    })
+    const onEnd = new Promise<void>((resolve) => vfsSum.once('end', resolve))
+    const streams = [binary, toStream(launchCode), vfsStream.pipe(vfsSum)]
 
-    const code = this.code(),
-      codeSize = Buffer.byteLength(code),
-      lengths = Buffer.from(Array(16))
-
-    const bundleBuffer = await this.bundle.toBuffer()
-
-    lengths.writeDoubleLE(codeSize, 0)
-    lengths.writeDoubleLE(bundleBuffer.length, 8)
-
-    return new (MultiStream as any)([
-      binary,
-      toStream(code),
-      toStream(bundleBuffer),
-      toStream(Buffer.concat([Buffer.from('<nexe~~sentinel>'), lengths])),
-    ])
+    let done = false
+    return new MultiStream(async (cb) => {
+      if (done) cb(null, null)
+      else if (streams.length) cb(null, streams.shift() as Readable)
+      else {
+        done = true
+        await onEnd
+        const trailers = Buffer.alloc(16)
+        trailers.writeDoubleLE(Buffer.byteLength(launchCode), 0)
+        trailers.writeDoubleLE(vfsSize, 8)
+        cb(null, toStream(Buffer.concat([Buffer.from('<nexe~~sentinel>'), trailers])))
+      }
+    })
   }
 }

src/fs/bundle.ts

@@ -1,11 +1,7 @@
-import * as fs from 'fs'
-import { promisify } from 'util'
 import { relative } from 'path'
 import { Readable } from 'stream'
-import { argv } from '../options'
 import { File } from 'resolve-dependencies'
-import MultiStream = require('multistream')
-const archiver: any = require('archiver')
+import archiver from 'archiver'
 
 function makeRelativeToZip(cwd: string, path: string) {
   return '/snapshot/' + relative(cwd, path)
@@ -45,13 +41,8 @@ export class Bundle {
     }
   }
 
-  public async toBuffer(): Promise<Buffer> {
-    this.zip.finalize()
-    const zipData: Buffer[] = []
-    this.zip.on('data', (data: Buffer) => zipData.push(data))
-    return await new Promise((resolve, reject) => {
-      this.zip.on('error', (error: Error) => reject(error))
-      this.zip.on('end', () => resolve(Buffer.concat(zipData)))
-    })
+  public async toStream(): Promise<Readable> {
+    await this.zip.finalize()
+    return this.zip
   }
 }

src/patches/boot-nexe.ts

@@ -1,14 +1,15 @@
 const fs = require('fs'),
   fd = fs.openSync(process.execPath, 'r'),
   stat = fs.statSync(process.execPath),
-  tailSize = Math.min(stat.size, 16000),
+  tailSize = Math.min(stat.size, 4096),
   tailWindow = Buffer.from(Array(tailSize))
 
 fs.readSync(fd, tailWindow, 0, tailSize, stat.size - tailSize)
 
 const footerPosition = tailWindow.indexOf('<nexe~~sentinel>')
-if (footerPosition == -1) {
-  throw 'Invalid Nexe binary'
+if (footerPosition === -1) {
+  process.stderr.write('Invalid Nexe binary')
+  process.exit(1)
 }
 
 const footer = tailWindow.slice(footerPosition, footerPosition + 32),