little-things/ia-cdx-search

#!/usr/bin/env python3
import asyncio
import collections
import json
import re
import shlex
import sys
import urllib.error
import urllib.request


def fetch(url, tries):
	for i in range(tries):
		try:
			print(f'GET {url}', file = sys.stderr)
			req = urllib.request.Request(url)
			with urllib.request.urlopen(req) as r:
				code = r.code
				print(f'{code} {url}', file = sys.stderr)
				if code != 200:
					raise RuntimeError(f'Could not fetch {url}')
				o = json.load(r)
				break
		except (RuntimeError, TimeoutError, urllib.error.URLError, json.JSONDecodeError) as e:
			print(f'Error retrieving {url}: {type(e).__module__}.{type(e).__name__} {e!s}', file = sys.stderr)
			if i == tries - 1:
				raise
	return url, code, o


async def wait_first_and_print(tasks):
	if not tasks:
		return
	task = tasks.popleft()
	url, code, o = await task
	assert o, 'got empty response'
	fields = o[0]
	assert all(len(v) == len(fields) for v in o[1:]), 'got unexpected response format'
	for row in o[1:]:
		print(json.dumps(dict(zip(fields, row))))
	print(f'Completed processing page {task._ia_cdx_page}', file = sys.stderr)
	return task._ia_cdx_page


async def main(query, concurrency = 1, tries = 1, startPage = None, numPages = None):
	assert (startPage is None) == (numPages is None)
	baseUrl = f'https://web.archive.org/cdx/search/cdx?{query}'
	if startPage is None:
		url = f'{baseUrl}&showNumPages=true'
		numPages = int(fetch(url, tries)[2])
		startPage = 0
		print(f'{numPages} pages', file = sys.stderr)

	loop = asyncio.get_running_loop()
	tasks = collections.deque()
	lastGoodPage = -1
	try:
		try:
			for page in range(startPage, numPages):
				while len(tasks) >= concurrency:
					lastGoodPage = await wait_first_and_print(tasks)
				url = f'{baseUrl}&output=json&page={page}'
				task = loop.run_in_executor(None, fetch, url, tries)
				task._ia_cdx_page = page
				tasks.append(task)
			while len(tasks) > 0:
				lastGoodPage = await wait_first_and_print(tasks)
		except:
			# It isn't possible to actually cancel a task running in a thread, so need to await them and discard any additional errors that occur.
			try:
				await asyncio.gather(*tasks)
			except:
				pass
			raise
	except (RuntimeError, json.JSONDecodeError, AssertionError):
		concurrencyS = f'--concurrency {concurrency} ' if concurrency != 1 else ''
		triesS = f'--tries {tries} ' if tries != 1 else ''
		print(f'To resume this search from where it crashed, run: ia-cdx-search {concurrencyS}{triesS}--page {lastGoodPage + 1} --numpages {numPages} {shlex.quote(query)}', file = sys.stderr)
		raise
	except (BrokenPipeError, KeyboardInterrupt):
		pass


def usage():
	print('Usage: ia-cdx-search [--concurrency N] [--tries N] [--page N --numpages N] QUERY', file = sys.stderr)
	print('Please refer to https://github.com/internetarchive/wayback/tree/master/wayback-cdx-server for the relevant query parameters', file = sys.stderr)
	print('The output, limit, resumeKey, showResumeKey, page, and showNumPages parameters must not be included.', file = sys.stderr)
	print('To resume a search that failed for some reason, provide the page number and number of pages through the second argument instead.', file = sys.stderr)
	print('Output is produces in JSONL format with one line per CDX entry.', file = sys.stderr)
	print('', file = sys.stderr)
	print('Examples:', file = sys.stderr)
	print(" - Subdomains: ia-cdx-search 'url=example.org&collapse=urlkey&fl=original&matchType=domain&filter=original:^https?://[^/]*example\.org(?::[0-9]*)?/'", file = sys.stderr)
	print('   Note that this will only find subdomains whose homepages are in the Wayback Machine. To discover all known subdomains, remove the filter and then extract the domains from the results.', file = sys.stderr)
	print(" - Subdirectories: ia-cdex-search 'url=example.org&collapse=urlkey&fl=original&matchType=domain&filter=original:^https?://[^/]*example\.org(?::[0-9]*)?/[^/]*/'", file = sys.stderr)
	print('   The same caveat applies. The directory must have been retrieved directly without an additional trailing path or query string.', file = sys.stderr)
	sys.exit(1)


args = sys.argv[1:]
if args[0].lower() in ('-h', '--help'):
	usage()
kwargs = {}
while args[0].startswith('--'):
	if args[0] == '--concurrency':
		kwargs['concurrency'] = int(args[1])
		args = args[2:]
	elif args[0] == '--tries':
		kwargs['tries'] = int(args[1])
		args = args[2:]
	elif args[0] == '--page' and args[2].lower() == '--numpages':
		kwargs['startPage'] = int(args[1])
		kwargs['numPages'] = int(args[3])
		args = args[4:]
	else:
		break
if len(args) != 1 or re.search(r'(^|&)(output|limit|resumekey|showresumekey|page|shownumpages)=', args[0], re.IGNORECASE):
	usage()
query = args[0]
asyncio.run(main(query, **kwargs))