fix: large results on small streams

Signed-off-by: Jan Kowalleck <jan.kowalleck@gmail.com>

Author: jkowalleck

HISTORY.md

@@ -4,6 +4,13 @@ All notable changes to this project will be documented in this file.
 
 ## unreleased
 
+* Fixed
+  * Writing large results to streams no longer drops data, but retries (via [#])
+* Docs
+  * Showcase programmatic CLI usage ([#1142] via [#])
+
+[#1142]: https://github.com/CycloneDX/cyclonedx-node-npm/issues/1142 
+
 ## 1.16.0 - 2023-12-11
 
 * Change

bin/cyclonedx-npm-cli.js

@@ -1,4 +1,5 @@
 #!/usr/bin/env node
+/* !!! do not remove/rename this file, it is public CLI in replacement for an API !!! */
 require('../dist/cli.js').run(process).catch(e => {
   process.stderr.write(`\n${e}\n`)
   return Math.max(1, Math.floor(Number(e?.code)) || 254)

src/_helpers.ts

@@ -17,11 +17,28 @@ SPDX-License-Identifier: Apache-2.0
 Copyright (c) OWASP Foundation. All Rights Reserved.
 */
 
-import { readFileSync } from 'fs'
+import { readFileSync, writeSync } from 'fs'
 
 export function loadJsonFile (path: string): any {
   return JSON.parse(readFileSync(path, 'utf8'))
   // may be replaced by `require(f, { with: { type: "json" } })`
   // as soon as this spec is properly implemented.
   // see https://github.com/tc39/proposal-import-attributes
 }
+
+export async function writeAllSync (fd: number, data: string): Promise<number> {
+  const b = Buffer.from(data)
+  const l = b.byteLength
+  let w = 0
+  while (w < l) {
+    try {
+      w += writeSync(fd, b, w)
+    } catch (error: any) {
+      if (error.code !== 'EAGAIN') {
+        throw error
+      }
+      await new Promise((resolve) => setTimeout(resolve, 100))
+    }
+  }
+  return w
+}

src/cli.ts

@@ -19,10 +19,10 @@ Copyright (c) OWASP Foundation. All Rights Reserved.
 
 import { Builders, Enums, Factories, Serialize, Spec, Validation } from '@cyclonedx/cyclonedx-library'
 import { Argument, Command, Option } from 'commander'
-import { existsSync, openSync, writeSync } from 'fs'
+import { existsSync, openSync } from 'fs'
 import { dirname, resolve } from 'path'
 
-import { loadJsonFile } from './_helpers'
+import { loadJsonFile, writeAllSync } from './_helpers'
 import { BomBuilder, TreeBuilder } from './builders'
 import { makeConsoleLogger } from './logger'
 
@@ -309,7 +309,7 @@ export async function run (process: NodeJS.Process): Promise<number> {
   }
 
   myConsole.log('LOG   | writing BOM to', options.outputFile)
-  const written = writeSync(
+  const written = await writeAllSync(
     options.outputFile === OutputStdOut
       ? process.stdout.fd
       : openSync(resolve(process.cwd(), options.outputFile), 'w'),

src/index.ts

@@ -17,5 +17,17 @@ SPDX-License-Identifier: Apache-2.0
 Copyright (c) OWASP Foundation. All Rights Reserved.
 */
 
-// not publishing anything at the moment
-export { }
+console.warn(`
+There is no public API. Instead, there is a well-thought, stable CLI.
+Call it programmatically like so:
+    const { execFileSync } = require('child_process')
+    const BUFFER_MAX_LENGTH = require('buffer').constants.MAX_LENGTH
+    const sbom = JSON.parse(execFileSync(process.execPath, [
+      '../path/to/this/module/bin/cyclonedx-npm-cli.js',
+      '--output-format', 'JSON',
+      '--output-file', '-'
+      // additional CLI args
+    ], { stdio: ['ignore', 'pipe', 'ignore'], encoding: 'buffer', maxBuffer: BUFFER_MAX_LENGTH }))
+`)
+
+export {/* See above! */}