ordigi/elodie/media/text.py

169 lines
4.8 KiB
Python

"""
The text module provides a base :class:`Text` class for text files that
are tracked by Elodie.
.. moduleauthor:: Jaisen Mathai <jaisen@jmathai.com>
"""
# load modules
from elodie import constants
from elodie.media.base import Base
from json import dumps, loads
import os
from shutil import copyfileobj
import time
class Text(Base):
"""The class for all text files.
:param str source: The fully qualified path to the text file.
"""
__name__ = 'Text'
#: Valid extensions for text files.
extensions = ('txt')
def __init__(self, source=None):
super(Text, self).__init__(source)
self.reset_cache()
def get_album(self):
self.parse_metadata_line()
if(not isinstance(self.metadata_line, dict) or
'album' not in self.metadata_line):
return None
return self.metadata_line['album']
def get_coordinate(self, type='latitude'):
self.parse_metadata_line()
if not self.metadata_line:
return None
elif type in self.metadata_line:
if type == 'latitude':
return self.metadata_line['latitude'] or None
elif type == 'longitude':
return self.metadata_line['longitude'] or None
return None
def get_date_taken(self):
source = self.source
self.parse_metadata_line()
# We return the value if found in metadata
if(isinstance(self.metadata_line, dict) and
'date_taken' in self.metadata_line):
return time.gmtime(self.metadata_line['date_taken'])
# If there's no date_taken in the metadata we return
# from the filesystem
seconds_since_epoch = min(
os.path.getmtime(source),
os.path.getctime(source)
)
return time.gmtime(seconds_since_epoch)
def get_metadata(self):
self.parse_metadata_line()
return super(Text, self).get_metadata()
def get_title(self):
self.parse_metadata_line()
if(not isinstance(self.metadata_line, dict) or
'title' not in self.metadata_line):
return None
return self.metadata_line['title']
def reset_cache(self):
"""Resets any internal cache
"""
self.metadata_line = None
super(Text, self).reset_cache()
def set_album(self, name):
status = self.write_metadata(album=name)
self.reset_cache()
return status
def set_location(self, latitude, longitude):
status = self.write_metadata(latitude=latitude, longitude=longitude)
self.reset_cache()
return status
def set_date_taken(self, passed_in_time):
if(time is None):
return False
seconds_since_epoch = time.mktime(passed_in_time.timetuple())
status = self.write_metadata(date_taken=seconds_since_epoch)
self.reset_cache()
return status
def parse_metadata_line(self):
if isinstance(self.metadata_line, dict):
return self.metadata_line
source = self.source
if source is None:
return None
with open(source, 'r') as f:
first_line = f.readline().strip()
try:
parsed_json = loads(first_line)
if isinstance(parsed_json, dict):
self.metadata_line = parsed_json
except ValueError:
if(constants.debug is True):
print 'Could not parse JSON from first line: %s' % first_line
pass
def write_metadata(self, **kwargs):
if len(kwargs) == 0:
return False
source = self.source
self.parse_metadata_line()
# Set defaults for a file without metadata
# Check if self.metadata_line is set and use that instead
metadata_line = {}
has_metadata = False
if isinstance(self.metadata_line, dict):
metadata_line = self.metadata_line
has_metadata = True
for name in kwargs:
metadata_line[name] = kwargs[name]
metadata_as_json = dumps(metadata_line)
if has_metadata:
# Update the first line of this file in place
# http://stackoverflow.com/a/14947384
with open(source, 'r') as f_read:
f_read.readline()
with open(source, 'w') as f_write:
f_write.write("{}\n".format(metadata_as_json))
copyfileobj(f_read, f_write)
else:
# Prepend the metadata to the file
with open(source, 'r') as f_read:
original_contents = f_read.read()
with open(source, 'w') as f_write:
f_write.write("{}\n{}".format(
metadata_as_json,
original_contents)
)
self.reset_cache()
return True