Turn images into print files from your own software

{
  "type": "https://optracy.com/docs/api#error-insufficient_credits",
  "title": "Not enough credits",
  "status": 402,
  "detail": "This job costs 1 credit; 0 are available.",
  "code": "insufficient_credits"
}

"""Turn one image into a print file with the Optracy processing API.

    OPTRACY_API_KEY=optr_... python api_example.py design.png svg design.svg

Python 3.8 or newer, standard library only. The key is read from the environment, never written in the code.
"""
import json
import os
import sys
import time
import urllib.error
import urllib.request
import uuid

API = os.environ.get('OPTRACY_API_BASE', 'https://api.optracy.com') + '/v1'
KEY = os.environ['OPTRACY_API_KEY']


def call(method, url, body=None, headers=None):
    """(status, headers, body) of one request, errors included."""
    headers = dict(headers or {}, Authorization='Bearer ' + KEY)
    request = urllib.request.Request(url, data=body, method=method, headers=headers)
    try:
        with urllib.request.urlopen(request, timeout=120) as answer:
            return answer.status, answer.headers, answer.read()
    except urllib.error.HTTPError as e:
        return e.code, e.headers, e.read()


def form(fields, image_path):
    """A multipart/form-data body with the fields and the image."""
    boundary = uuid.uuid4().hex
    parts = [('--%s\r\nContent-Disposition: form-data; name="%s"\r\n\r\n%s\r\n' % (boundary, k, v)).encode()
             for k, v in fields.items()]
    with open(image_path, 'rb') as f:
        parts.append(('--%s\r\nContent-Disposition: form-data; name="image"; filename="%s"\r\n'
                      'Content-Type: application/octet-stream\r\n\r\n'
                      % (boundary, os.path.basename(image_path))).encode() + f.read() + b'\r\n')
    parts.append(('--%s--\r\n' % boundary).encode())
    return b''.join(parts), 'multipart/form-data; boundary=' + boundary


def wait(headers):
    time.sleep(int(headers.get('Retry-After') or 3))


def convert(image_path, file_format, out_path):
    body, content_type = form({'format': file_format}, image_path)
    # The same key on every try: a request sent again never starts a second job.
    headers = {'Content-Type': content_type, 'Idempotency-Key': str(uuid.uuid4())}
    for _ in range(5):
        status, answer_headers, answer = call('POST', API + '/jobs', body, headers)
        if status not in (429, 503):
            break
        wait(answer_headers)
    job = json.loads(answer)
    if status != 202:
        sys.exit('refused: %s (%s)' % (job['code'], job['detail']))

    while job['status'] in ('queued', 'running'):
        wait(answer_headers)
        status, answer_headers, answer = call('GET', API + '/jobs/' + job['id'])
        if status == 200:
            job = json.loads(answer)
        elif status != 429:
            sys.exit('could not read the job: %s' % json.loads(answer)['code'])

    if job['status'] != 'succeeded':
        sys.exit('job %s: %s' % (job['status'], (job['error'] or {}).get('detail', '')))
    status, _, data = call('GET', job['result']['url'])
    if status != 200:
        sys.exit('could not download the file: %s' % json.loads(data)['code'])
    with open(out_path, 'wb') as f:
        f.write(data)
    print('%s: %d bytes, %d colors, %d credit charged' % (out_path, len(data), job['result']['colors'],
                                                          job['credits_charged']))


if __name__ == '__main__':
    if len(sys.argv) != 4:
        sys.exit('usage: python api_example.py <image> <svg|pdf|eps|png> <file to write>')
    convert(*sys.argv[1:])

OPTRACY_API_KEY=optr_… python api_example.py design.jpg svg design.svg

// Turn one image into a print file with the Optracy processing API.
//
//   OPTRACY_API_KEY=optr_... node api_example.mjs design.png svg design.svg
//
// Node.js 18 or newer, no package needed. The key is read from the environment, never written in the code.
import { randomUUID } from 'node:crypto';
import { readFile, writeFile } from 'node:fs/promises';
import { basename } from 'node:path';

const API = (process.env.OPTRACY_API_BASE || 'https://api.optracy.com') + '/v1';
const auth = { Authorization: 'Bearer ' + process.env.OPTRACY_API_KEY };
const wait = (answer) => new Promise((done) => setTimeout(done, 1000 * Number(answer.headers.get('Retry-After') || 3)));

const [imagePath, format, outPath] = process.argv.slice(2);
if (!outPath) throw new Error('usage: node api_example.mjs <image> <svg|pdf|eps|png> <file to write>');

const form = new FormData();
form.append('format', format);
form.append('image', new Blob([await readFile(imagePath)]), basename(imagePath));
// The same key on every try: a request sent again never starts a second job.
const headers = { ...auth, 'Idempotency-Key': randomUUID() };

let answer;
for (let i = 0; i < 5; i++) {
  answer = await fetch(API + '/jobs', { method: 'POST', headers, body: form });
  if (answer.status !== 429 && answer.status !== 503) break;
  await wait(answer);
}
let job = await answer.json();
if (answer.status !== 202) throw new Error(`refused: ${job.code} (${job.detail})`);

while (job.status === 'queued' || job.status === 'running') {
  await wait(answer);
  answer = await fetch(`${API}/jobs/${job.id}`, { headers: auth });
  if (answer.status === 200) job = await answer.json();
  else if (answer.status !== 429) throw new Error('could not read the job: ' + (await answer.json()).code);
}

if (job.status !== 'succeeded') throw new Error(`job ${job.status}: ${job.error ? job.error.detail : ''}`);
const file = await fetch(job.result.url, { headers: auth });
if (file.status !== 200) throw new Error('could not download the file: ' + (await file.json()).code);
const data = Buffer.from(await file.arrayBuffer());
await writeFile(outPath, data);
console.log(`${outPath}: ${data.length} bytes, ${job.result.colors} colors, ${job.credits_charged} credit charged`);

OPTRACY_API_KEY=optr_… node api_example.mjs design.jpg svg design.svg