diff --git a/swh/fetcher/googlecode/loader.py b/swh/fetcher/googlecode/loader.py index 669f25a..fbd2568 100644 --- a/swh/fetcher/googlecode/loader.py +++ b/swh/fetcher/googlecode/loader.py @@ -1,150 +1,162 @@ # Copyright (C) 2015-2016 The Software Heritage developers # See the AUTHORS file at the top-level directory of this distribution # License: GNU General Public License version 3, or any later version # See top-level LICENSE file for more information import logging import os import requests from swh.core import config, hashutil from .utils import transform from .hashutil import md5_hash, md5_from_b64 class SWHGoogleFetcher(config.SWHConfig): """A swh data fetcher loader. This fetcher will: - retrieve the archive metadata and write it to disk. - download the archive to retrieve and write it to disk. - check that size and checksums (md5, crc32c) match those describe in the metadata. """ def __init__(self): self.log = logging.getLogger('swh.fetcher.google.SWHGoogleFetcher') l = logging.getLogger('requests.packages.urllib3.connectionpool') l.setLevel(logging.WARN) + def load_meta(self, filepath): + """Try and load the metadata from the given filepath. + It is assumed that the code is called after checking the file exists. + + """ + import json + try: + with open(filepath, 'r') as f: + return json.loads(f.read()) + except: + return None + def retrieve_source_meta(self, url_meta, filepath_meta): if os.path.exists(filepath_meta): - import json - with open(filepath_meta, 'r') as f: - meta = json.loads(f.read()) + meta = self.load_meta(filepath_meta) + if meta: # some meta could be corrupted, so we try to load them + return meta + # and if we fail, we try to fetch them again + + meta = {} + try: + r = requests.get(url_meta) + except Exception as e: + msg = 'Problem when fetching metadata %s.' % url_meta + self.log.error(msg) + raise ValueError(msg, e) else: - meta = {} - try: - r = requests.get(url_meta) - except Exception as e: - msg = 'Problem when fetching metadata %s.' % url_meta - self.log.error(msg) - raise ValueError(msg, e) - else: - meta = r.json() - - with open(filepath_meta, 'w') as f: - f.write(r.text) + meta = r.json() + with open(filepath_meta, 'w') as f: + f.write(r.text) return meta def retrieve_source(self, url, filepath): if not os.path.exists(filepath): self.log.debug('Fetching %s\' raw data.' % url) try: r = requests.get(url, stream=True) except Exception as e: msg = 'Problem when fetching file %s.' % url self.log.error(msg) raise ValueError(msg, e) else: if not r.ok: msg = 'Problem when fetching file %s.' % url self.log.error(msg) raise ValueError(msg) else: with open(filepath, 'wb') as f: for chunk in r.iter_content(hashutil.HASH_BLOCK_SIZE): f.write(chunk) def check_source(self, meta, filepath): expected = { 'md5': md5_from_b64(meta['md5Hash']), 'size': int(meta['size']) } error = False actual_size = os.path.getsize(filepath) if actual_size != expected['size']: msg = 'Bad size. Expected: %s. Got: %s' % ( expected['size'], actual_size) self.log.error(msg) error = True self.log.debug('Checking %s\' raw data checksums and size.' % filepath) # Last, check the metadata are ok with open(filepath, 'rb') as f: md5_h = md5_hash(f) if md5_h != expected['md5']: msg = 'Bad md5 signature. Expected: %s. Got: %s' % ( expected['md5'], md5_h) self.log.error(msg) error = True return error def process(self, archive_gs, destination_rootpath): self.log.info('Fetch %s\'s metadata' % archive_gs) # First retrieve the archive gs's metadata parent_dir, filename, url_meta, url_content = transform( archive_gs) parent_dir = os.path.join(destination_rootpath, parent_dir) os.makedirs(parent_dir, exist_ok=True) project_name = os.path.basename(parent_dir) filename = project_name + '-' + filename filename_meta = filename + '.json' filepath = os.path.join(parent_dir, filename) filepath_meta = os.path.join(parent_dir, filename_meta) meta = self.retrieve_source_meta(url_meta, filepath_meta) if not meta: raise ValueError('Fail to download metadata, stop.') # check existence of the file if os.path.exists(filepath): # it already exists, check it's ok errors = self.check_source(meta, filepath) if errors: if os.path.exists(filepath): self.log.error('Clean corrupted file %s' % filepath) os.remove(filepath) else: # it's ok, we are done! self.log.info('Archive %s already fetched!' % archive_gs) return # the file does not exist, we retrieve it self.retrieve_source(meta['mediaLink'], filepath) # Third - Check the retrieved source errors = self.check_source(meta, filepath) if errors: if os.path.exists(filepath): filepath_corrupted = filepath + '.corrupted' self.log.error('Rename corrupted file %s to %s' % ( os.path.basename(filepath), os.path.basename(filepath_corrupted))) os.rename(filepath, filepath_corrupted) else: self.log.info('Archive %s fetched.' % archive_gs)