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# http://pyrocko.org - GPLv3
#
# The Pyrocko Developers, 21st Century
# ---|P------/S----------~Lg----------
from __future__ import absolute_import, print_function
import time
import logging
from builtins import str as newstr
from pyrocko.io_common import FileLoadError
from pyrocko.progress import progress
from .backends import \
mseed, sac, datacube, stationxml, textfiles, virtual, yaml, tdms_idas
from ..model import to_kind_ids
backend_modules = [
mseed, sac, datacube, stationxml, textfiles, virtual, yaml, tdms_idas]
logger = logging.getLogger('pyrocko.sqirrel.io')
def make_task(*args, **kwargs):
kwargs['logger'] = logger
return progress.task(*args, **kwargs)
def update_format_providers():
'''Update global mapping from file format to io backend module.'''
global g_format_providers
g_format_providers = {}
for mod in backend_modules:
for format in mod.provided_formats():
if format not in g_format_providers:
g_format_providers[format] = []
g_format_providers[format].append(mod)
g_format_providers = {}
update_format_providers()
class FormatDetectionFailed(FileLoadError):
'''
Exception raised when file format detection fails.
'''
def __init__(self, path):
FileLoadError.__init__(
self, 'format detection failed for file: %s' % path)
class UnknownFormat(Exception):
'''
Exception raised when user requests an unknown file format.
'''
def __init__(self, format):
Exception.__init__(
self, 'unknown format: %s' % format)
def get_backend(fmt):
'''
Get squirrel io backend module for a given file format.
:params str fmt: format identifier
'''
try:
return g_format_providers[fmt][0]
except KeyError:
raise UnknownFormat(fmt)
def detect_format(path):
'''
Determine file type from first 512 bytes.
:param str path: path of file
'''
if path.startswith('virtual:'):
return 'virtual'
try:
with open(path, 'rb') as f:
data = f.read(512)
except (OSError, IOError):
raise FormatDetectionFailed(path)
fmt = None
for mod in backend_modules:
fmt = mod.detect(data)
if fmt is not None:
return fmt
raise FormatDetectionFailed(path)
def supported_formats():
'''
Get list of file formats supported by Squirrel.
'''
return sorted(g_format_providers.keys())
g_content_kinds = ['waveform', 'station', 'channel', 'response', 'event']
def supported_content_kinds():
'''
Get list of supported content kinds offered through Squirrel.
'''
return g_content_kinds
def iload(
paths,
segment=None,
format='detect',
database=None,
check=True,
commit=True,
skip_unchanged=False,
content=g_content_kinds):
'''
Iteratively load content or index/reindex meta-information from files.
:param paths: iterator yielding file names to load from or
:py:class:`pyrocko.squirrel.Selection` object
:param str segment: file-specific segment identifier (con only be used
when loading from a single file.
:param str format: file format identifier or ``'detect'`` for
autodetection. When loading from a selection, per-file format
assignation is taken from the hint in the selection and this flag is
ignored.
:param database: database to use for meta-information caching
:type database: :py:class:`pyrocko.squirrel.Database`
:param bool check: if ``True``, investigate modification time and file
sizes of known files to debunk modified files (pessimistic mode), or
``False`` to deactivate checks (optimistic mode)
:param bool commit: flag, whether to commit updated information to the
meta-information database
:param bool skip_unchanged: if ``True``, only yield index nuts
for new / modified files
:param content: list of strings, selection of content types to load
This generator yields :py:class:`pyrocko.squirrel.Nut` objects for
individual pieces of information found when reading the given files. Such a
nut may represent a waveform, a station, a channel, an event or other data
type. The nut itself only contains the meta-information. The actual content
information is attached to the nut if requested. All nut meta-information
is stored in the squirrel meta-information database. If possible, this
function avoids accessing the actual disk files and provides the requested
information straight from the database. Modified files are recognized and
reindexed as needed.
'''
from ..base import Selection
n_db = 0
n_load = 0
selection = None
kind_ids = to_kind_ids(content)
if isinstance(paths, (str, newstr)):
paths = [paths]
else:
if segment is not None:
raise TypeError(
'iload: segment argument can only be used when loading from '
'a single file')
if isinstance(paths, Selection):
selection = paths
if database is not None:
raise TypeError(
'iload: database argument must be None when called with a '
'selection')
database = selection.get_database()
if skip_unchanged and not isinstance(paths, Selection):
raise TypeError(
'iload: need selection when called with "skip_unchanged=True"')
temp_selection = None
if database:
if not selection:
temp_selection = database.new_selection(paths)
selection = temp_selection
if skip_unchanged:
selection.flag_modified(check)
it = selection.undig_grouped(skip_unchanged=True)
else:
it = selection.undig_grouped()
else:
it = (((format, path), []) for path in paths)
try:
n_files_total = len(it)
except TypeError:
n_files_total = None
task = None
if progress is not None:
if not kind_ids:
task = make_task('Indexing files', n_files_total)
else:
task = make_task('Loading files', n_files_total)
n_files = 0
tcommit = time.time()
database_modified = False
for (format, path), old_nuts in it:
if task is not None:
condition = '(nuts: %i from file, %i from cache)\n %s' % (
n_load, n_db, path)
task.update(n_files, condition)
n_files += 1
if database and commit and database_modified:
tnow = time.time()
if tnow - tcommit > 20. or n_files % 1000 == 0:
database.commit()
tcommit = tnow
try:
if check and old_nuts and old_nuts[0].file_modified():
old_nuts = []
if segment is not None:
old_nuts = [
nut for nut in old_nuts if nut.file_segment == segment]
if old_nuts:
db_only_operation = not kind_ids or all(
nut.kind_id in kind_ids and nut.content_in_db
for nut in old_nuts)
if db_only_operation:
# logger.debug('using cached information for file %s, '
# % path)
for nut in old_nuts:
if nut.kind_id in kind_ids:
database.undig_content(nut)
n_db += 1
yield nut
continue
if format == 'detect':
if old_nuts and not old_nuts[0].file_modified():
format_this = old_nuts[0].file_format
else:
format_this = detect_format(path)
else:
format_this = format
mod = get_backend(format_this)
mtime, size = mod.get_stats(path)
logger.debug('reading file %s' % path)
nuts = []
for nut in mod.iload(format_this, path, segment, content):
nut.file_path = path
nut.file_format = format_this
nut.file_mtime = mtime
nut.file_size = size
nuts.append(nut)
n_load += 1
yield nut
if database and nuts != old_nuts:
if segment is not None:
nuts = mod.iload(format_this, path, None, [])
for nut in nuts:
nut.file_path = path
nut.file_format = format_this
nut.file_mtime = mtime
database.dig(nuts)
database_modified = True
except FileLoadError:
logger.error('An error occured while reading file: %s' % path)
if database:
database.reset(path)
database_modified = True
if task is not None:
condition = '(nuts: %i from file, %i from cache)' % (n_load, n_db)
task.update(n_files, condition)
task.done(condition)
if database:
if commit and database_modified:
database.commit()
if temp_selection:
del temp_selection
logger.debug('iload: from cache: %i, from files: %i, files: %i' % (
n_db, n_load, n_files))
__all__ = [
'iload',
'detect_format',
'supported_formats',
'supported_content_kinds',
'get_backend',
'FormatDetectionFailed',
'UnknownFormat',
]
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