- import fcntl
- import gzip
- import io
- import itertools
- import json
- import logging
- import os
- import qwarc.utils
- import tempfile
- import time
- import warcio
-
-
- class WARC:
- def __init__(self, prefix, maxFileSize, dedupe, command, specFile, specDependencies, logFilename):
- '''
- Initialise the WARC writer
-
- prefix: str, path prefix for WARCs; a dash, a five-digit number, and ".warc.gz" will be appended.
- maxFileSize: int, maximum size of an individual WARC. Use 0 to disable splitting.
- dedupe: bool, whether to enable record deduplication
- command: list, the command line call for qwarc
- specFile: str, path to the spec file
- specDependencies: qwarc.utils.SpecDependencies
- logFilename: str, name of the log file written by this process
- '''
-
- self._prefix = prefix
- self._counter = 0
- self._maxFileSize = maxFileSize
-
- self._closed = True
- self._file = None
- self._journalFile = None
- self._journalClean = None
- self._warcWriter = None
-
- self._dedupe = dedupe
- self._dedupeMap = {}
-
- self._command = command
- self._specFile = specFile
- self._specDependencies = specDependencies
-
- self._logFilename = logFilename
-
- self._metaWarcinfoRecordID = None
- self._write_meta_warc(self._write_initial_meta_records)
-
- def _ensure_opened(self):
- '''Open the next file that doesn't exist yet if there is currently no file opened'''
-
- if not self._closed:
- return
- while True:
- filename = f'{self._prefix}-{self._counter:05d}.warc.gz'
- try:
- # Try to open the file for writing, requiring that it does not exist yet, and attempt to get an exclusive, non-blocking lock on it
- self._file = open(filename, 'xb')
- fcntl.flock(self._file.fileno(), fcntl.LOCK_EX | fcntl.LOCK_NB)
- except FileExistsError:
- logging.info(f'{filename} already exists, skipping')
- self._counter += 1
- else:
- break
- logging.info(f'Opened {filename}')
- self._open_journal(filename)
- self._warcWriter = warcio.warcwriter.WARCWriter(self._file, gzip = True, warc_version = '1.1')
- self._closed = False
- self._counter += 1
-
- def _open_journal(self, filename):
- try:
- self._journalFile = open(f'{filename}.qwarcjournal', 'xb')
- fcntl.flock(self._journalFile.fileno(), fcntl.LOCK_EX | fcntl.LOCK_NB)
- except FileExistsError:
- logging.error(f'{filename}.qwarcjournal already exists!')
- raise RuntimeError(f'Unable to create journal file for {filename}: {filename}.qwarcjournal already exists')
- except OSError as e:
- if e.errno == errno.EWOULDBLOCK:
- logging.error(f'{filename}.qwarcjournal is already locked!')
- raise RuntimeError(f'Unable to lock journal file {filename}.qwarcjournal') from e
- raise
- self._journalClean = True
-
- def _write_record(self, record):
- # Write the current offset to the journal file
- # Since the size can only grow, it is not necessary to explicitly delete the previous contents.
- self._journalFile.seek(0)
- previousSize = self._file.tell()
- self._journalFile.write(f'qwarc journal version: 1\noffset: {previousSize}\nwrite ok: no \n'.encode('ascii'))
- self._journalFile.flush()
- self._journalClean = False
-
- try:
- self._warcWriter.write_record(record)
- except (OSError, IOError):
- self._file.truncate(previousSize)
- raise
- else:
- # Mark the write as ok
- self._journalFile.seek(-4, os.SEEK_END) # len(b'no \n')
- self._journalFile.write(b'yes\n')
- self._journalFile.flush()
- self._journalClean = True
-
- def _write_warcinfo_record(self):
- data = {
- 'software': qwarc.utils.get_software_info(self._specDependencies.packages),
- 'command': self._command,
- 'files': {
- 'spec': self._specFile,
- 'spec-dependencies': self._specDependencies.files
- },
- 'extra': self._specDependencies.extra,
- }
- payload = io.BytesIO(json.dumps(data, indent = 2).encode('utf-8'))
- # Workaround for https://github.com/webrecorder/warcio/issues/87
- digester = warcio.utils.Digester('sha1')
- digester.update(payload.getvalue())
- record = self._warcWriter.create_warc_record(
- None,
- 'warcinfo',
- payload = payload,
- warc_headers_dict = {'Content-Type': 'application/json; charset=utf-8', 'WARC-Block-Digest': str(digester)},
- length = len(payload.getvalue()),
- )
- self._write_record(record)
- return record.rec_headers.get_header('WARC-Record-ID')
-
- def write_client_response(self, response):
- '''
- Write the requests and responses stored in a ClientResponse instance to the currently opened WARC.
- A new WARC will be started automatically if the size of the current file exceeds the limit after writing all requests and responses from this `response` to the current WARC.
- '''
-
- self._ensure_opened()
- for r in response.iter_all():
- usec = f'{(r.rawRequestTimestamp - int(r.rawRequestTimestamp)):.6f}'[2:]
- requestDate = time.strftime(f'%Y-%m-%dT%H:%M:%S.{usec}Z', time.gmtime(r.rawRequestTimestamp))
- r.rawRequestData.seek(0, io.SEEK_END)
- length = r.rawRequestData.tell()
- r.rawRequestData.seek(0)
- requestRecord = self._warcWriter.create_warc_record(
- str(r.url),
- 'request',
- payload = r.rawRequestData,
- length = length,
- warc_headers_dict = {
- 'WARC-Date': requestDate,
- 'WARC-IP-Address': r.remoteAddress[0],
- 'WARC-Warcinfo-ID': self._metaWarcinfoRecordID,
- }
- )
- requestRecordID = requestRecord.rec_headers.get_header('WARC-Record-ID')
- r.rawResponseData.seek(0, io.SEEK_END)
- length = r.rawResponseData.tell()
- r.rawResponseData.seek(0)
- responseRecord = self._warcWriter.create_warc_record(
- str(r.url),
- 'response',
- payload = r.rawResponseData,
- length = length,
- warc_headers_dict = {
- 'WARC-Date': requestDate,
- 'WARC-IP-Address': r.remoteAddress[0],
- 'WARC-Concurrent-To': requestRecordID,
- 'WARC-Warcinfo-ID': self._metaWarcinfoRecordID,
- }
- )
- payloadDigest = responseRecord.rec_headers.get_header('WARC-Payload-Digest')
- assert payloadDigest is not None
- if self._dedupe and responseRecord.payload_length > 100: # Don't deduplicate small responses; the additional headers are typically larger than the payload dedupe savings...
- if payloadDigest in self._dedupeMap:
- refersToRecordId, refersToUri, refersToDate = self._dedupeMap[payloadDigest]
- responseHttpHeaders = responseRecord.http_headers
- responseRecord = self._warcWriter.create_revisit_record(
- str(r.url),
- digest = payloadDigest,
- refers_to_uri = refersToUri,
- refers_to_date = refersToDate,
- http_headers = responseHttpHeaders,
- warc_headers_dict = {
- 'WARC-Date': requestDate,
- 'WARC-IP-Address': r.remoteAddress[0],
- 'WARC-Concurrent-To': requestRecordID,
- 'WARC-Refers-To': refersToRecordId,
- 'WARC-Truncated': 'length',
- 'WARC-Warcinfo-ID': self._metaWarcinfoRecordID,
- }
- )
- # Workaround for https://github.com/webrecorder/warcio/issues/94
- responseRecord.rec_headers.replace_header('WARC-Profile', 'http://netpreserve.org/warc/1.1/revisit/identical-payload-digest')
- else:
- self._dedupeMap[payloadDigest] = (responseRecord.rec_headers.get_header('WARC-Record-ID'), str(r.url), requestDate)
- self._write_record(requestRecord)
- self._write_record(responseRecord)
-
- if self._maxFileSize and self._file.tell() > self._maxFileSize:
- self._close_file()
-
- def _write_resource_records(self):
- '''Write spec file and dependencies'''
- assert self._metaWarcinfoRecordID is not None, 'write_warcinfo_record must be called first'
-
- for type_, contentType, fn in itertools.chain((('specfile', 'application/x-python', self._specFile),), map(lambda x: ('spec-dependency-file', 'application/octet-stream', x), self._specDependencies.files)):
- with open(fn, 'rb') as f:
- f.seek(0, io.SEEK_END)
- length = f.tell()
- f.seek(0)
- record = self._warcWriter.create_warc_record(
- f'file://{fn}',
- 'resource',
- payload = f,
- length = length,
- warc_headers_dict = {'X-QWARC-Type': type_, 'WARC-Warcinfo-ID': self._metaWarcinfoRecordID, 'Content-Type': contentType},
- )
- self._write_record(record)
-
- def _write_initial_meta_records(self):
- self._metaWarcinfoRecordID = self._write_warcinfo_record()
- self._write_resource_records()
-
- def _write_log_record(self):
- assert self._metaWarcinfoRecordID is not None, 'write_warcinfo_record must be called first'
-
- rootLogger = logging.getLogger()
- for handler in rootLogger.handlers: #FIXME: Uses undocumented attribute handlers
- handler.flush()
- with open(self._logFilename, 'rb') as fp:
- fp.seek(0, io.SEEK_END)
- length = fp.tell()
- fp.seek(0)
- # Work around https://github.com/webrecorder/warcio/issues/90
- payload = qwarc.utils.FrozenFileView(fp, 0, length)
- record = self._warcWriter.create_warc_record(
- f'file://{self._logFilename}',
- 'resource',
- payload = payload,
- length = length,
- warc_headers_dict = {'X-QWARC-Type': 'log', 'Content-Type': 'text/plain; charset=utf-8', 'WARC-Warcinfo-ID': self._metaWarcinfoRecordID},
- )
- self._write_record(record)
-
- def _close_file(self):
- '''Close the currently opened WARC'''
-
- if not self._closed:
- self._file.close()
- journalFilename = self._journalFile.name
- self._journalFile.close()
- if self._journalClean:
- os.remove(journalFilename)
- self._warcWriter = None
- self._file = None
- self._journalFile = None
- self._journalClean = None
- self._closed = True
-
- def _write_meta_warc(self, callback):
- filename = f'{self._prefix}-meta.warc.gz'
- self._file = open(filename, 'ab')
- try:
- fcntl.flock(self._file.fileno(), fcntl.LOCK_EX)
- logging.info(f'Opened {filename}')
- self._open_journal(filename)
- self._warcWriter = warcio.warcwriter.WARCWriter(self._file, gzip = True, warc_version = '1.1')
- self._closed = False
-
- callback()
- finally:
- self._close_file()
-
- def close(self):
- '''Clean up everything.'''
- self._close_file()
- self._write_meta_warc(self._write_log_record)
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