class SipCreator:
def __init__( self, jobs, jobname=datetime.now().strftime( "%Y%m%d%H%M%S" ), warcs=None, viral=None, logs=None, start_date=None, dummy_run=False, hash_cache_file=None, client=None ):
"""Sets up fields."""
if client is None:
self.client = hdfs.InsecureClient(cfg.get('hdfs','url'), user=cfg.get('hdfs','user'))
else:
self.client = client
self.dummy = dummy_run
if self.dummy:
logger.info("This is a dummy-run - no real ARKs will be minted.")
self.overwrite = False
self.jobs = jobs
self.jobname = jobname
self.warcs = warcs
self.viral = viral
self.logs = logs
self.hash_cache = {}
self.parse_hash_cache(hash_cache_file)
self.startdate = start_date
self.BAGIT_CONTACT_NAME="Andrew N. Jackson"
self.BAGIT_CONTACT_EMAIL="*****@*****.**"
self.BAGIT_DESCRIPTION="LD Crawl: "
self.ARK_URL="http://pii.ad.bl.uk/pii/vdc?arks="
self.ARK_PREFIX="ark:/81055/vdc_100022535899.0x"
# And create:
logger.info("Processing job files...")
self.processJobs()
logger.info("Generating METS...")
self.createMets()
def parse_hash_cache(self, hash_cache_file=None):
if hash_cache_file is None:
self.hash_cache = None
return
# Parse and populate the files generated by the HdfsFileHasher
# /hdfs/path/to/directory<tab>SHA-512 Length /hdfs/full/path/including/filename.warc.gz
self.viral = []
self.warcs = []
self.logs = []
with open(hash_cache_file,'r') as f:
for line in f:
(dir, details) = line.split('\t')
(hash, length, path) = details.split(' ')
path = path.strip()
length = long(length)
logger.debug("GOT %s %s %s" % (path, hash, length))
self.hash_cache[path] = "%s %i" % ( hash, length )
if "/output/viral/" in path:
self.viral.append(path)
elif "/output/warcs/" in path:
self.warcs.append(path)
else:
self.logs.append(path)
def processJobs( self ):
"""All WARCs and logs associated with jobs, optionally loaded from files."""
if not isinstance(self.warcs,list):
with open(self.warcs, "r") as i:
self.warcs = [w.strip() for w in i]
if not isinstance(self.viral,list):
with open(self.viral, "r") as i:
self.viral = [v.strip() for v in i]
if not isinstance(self.logs,list):
with open(self.logs, "r") as i:
self.logs = [l.strip() for l in i]
if self.startdate is None and self.dummy:
self.startdate = datetime.now().isoformat()
if( self.dummy ):
logger.info( "Getting dummy ARK identifiers..." )
self.getDummyIdentifiers( len( self.warcs ) + len( self.viral ) + len( self.logs ) )
else:
logger.info( "Getting ARK identifiers..." )
self.getIdentifiers( len( self.warcs ) + len( self.viral ) + len( self.logs ) )
def createMets( self ):
"""Creates the Mets object."""
logger.info( "Building METS..." )
self.mets = Mets( self.startdate, self.warcs, self.viral, self.logs, self.identifiers, hash_cache=self.hash_cache, client=self.client )
def writeMets( self, output=sys.stdout ):
"""Writes the METS XML to a file handle."""
output.write( self.mets.getXml() )
def bagit( self, directory, metadata=None ):
"""Creates a Bagit, if needs be with default metadata."""
if metadata is None:
metadata = { "Contact-Name": self.BAGIT_CONTACT_NAME, "Contact-Email": self.BAGIT_CONTACT_EMAIL, "Timestamp": datetime.now().strftime( "%Y-%m-%dT%H:%M:%SZ" ), "Description": self.BAGIT_DESCRIPTION + ";".join( self.jobs ) }
bagit.make_bag( directory, metadata )
def getDummyIdentifiers( self, num ):
"""Provides a series of 'dummy' identifiers for testing purposes."""
self.identifiers = []
for i in range( num ):
self.identifiers.append( "%s%s" % ( self.ARK_PREFIX, "{0:06d}".format( i ) ) )
def getIdentifiers( self, num ):
"""Retrieves 'num' ARK identifiers from a webservice; alternatively calls an
alternate method to provide 'dummy' identifiers."""
self.identifiers = []
if( self.dummy ):
return self.getDummyIdentifiers( num )
try:
url = "%s%s" % ( self.ARK_URL, str( num ) )
logger.debug( "Requesting %s ARKS: %s" % ( num, url ) )
response = requests.post( url )
data = response.content
except Exception as e:
logger.error( "Could not obtain ARKs: %s" % str( e ) )
raise Exception( "Could not obtain ARKs: %s" % str( e ) )
xml = parseString( data )
for ark in xml.getElementsByTagName( "ark" ):
self.identifiers.append( ark.firstChild.wholeText )
if( len( self.identifiers ) != num ):
raise Exception( "Problem parsing ARKs; %s, %s, %s" % ( self.jobs, self.identifiers, data ) )
def verifySetup(self):
return True
def create_sip(self, sip_dir):
"""Creates a SIP and returns the path to the folder containing the METS."""
if self.verifySetup():
if not os.path.exists(sip_dir):
os.makedirs(sip_dir)
else:
raise Exception("SIP directory already exists: %s" % sip_dir)
with open("%s/%s.xml" % (sip_dir, self.jobname.replace('/','_')), "wb") as o:
self.writeMets(o)
self.bagit(sip_dir)
else:
raise Exception("Could not verify SIP for %s" % sip_dir)
return sip_dir
def copy_sip_to_hdfs(self, sip_dir, hdfs_sip_path):
"""
Creates a tarball of a SIP and copies to HDFS.
"""
# Check if it's already there:
hdfs_sip_tgz = "%s.tar.gz" % hdfs_sip_path
status = self.client.status(hdfs_sip_tgz, strict=False)
if status and not self.overwrite:
raise Exception("SIP already exists in HDFS: %s" % hdfs_sip_tgz)
# Build the TGZ
gztar = shutil.make_archive(base_name=sip_dir, format="gztar", root_dir=os.path.dirname(sip_dir),
base_dir=os.path.basename(sip_dir))
if self.dummy:
logger.warning("Not copying to HDFS as this is a dummy-run! Leaving %s in place." % gztar)
else:
logger.info("Copying %s to HDFS..." % gztar)
with open(gztar,'r') as f:
self.client.write(data=f, hdfs_path=hdfs_sip_tgz, overwrite=False)
os.remove(gztar)
logger.info("Done.")
return hdfs_sip_tgz
def createMets( self ):
"""Creates the Mets object."""
logger.info( "Building METS..." )
self.mets = Mets( self.startdate, self.warcs, self.viral, self.logs, self.identifiers, hash_cache=self.hash_cache, client=self.client )
