"""CSV to database or vice versa."""
import csv
+import fnmatch
+import os.path
import pkg_resources
import sys
from sqlalchemy.orm.attributes import instrumentation_registry
+import sqlalchemy.sql.util
import sqlalchemy.types
from pokedex.db import metadata
import pokedex.db.tables as tables
-def load(session, directory=None, drop_tables=False):
+def _get_table_names(metadata, patterns):
+ """Returns a list of table names from the given metadata. If `patterns`
+ exists, only tables matching one of the patterns will be returned.
+ """
+ if patterns:
+ table_names = set()
+ for pattern in patterns:
+ if '.' in pattern or '/' in pattern:
+ # If it looks like a filename, pull out just the table name
+ _, filename = os.path.split(pattern)
+ table_name, _ = os.path.splitext(filename)
+ pattern = table_name
+
+ table_names.update(fnmatch.filter(metadata.tables.keys(), pattern))
+ else:
+ table_names = metadata.tables.keys()
+
+ return list(table_names)
+
+def _get_verbose_prints(verbose):
+ """If `verbose` is true, returns three functions: one for printing a
+ starting message, one for printing an interim status update, and one for
+ printing a success or failure message when finished.
+
+ If `verbose` is false, returns no-op functions.
+ """
+
+ if not verbose:
+ # Return dummies
+ def dummy(*args, **kwargs):
+ pass
+
+ return dummy, dummy, dummy
+
+ ### Okay, verbose == True; print stuff
+
+ def print_start(thing):
+ # Truncate to 66 characters, leaving 10 characters for a success
+ # or failure message
+ truncated_thing = thing[0:66]
+
+ # Also, space-pad to keep the cursor in a known column
+ num_spaces = 66 - len(truncated_thing)
+
+ print "%s...%s" % (truncated_thing, ' ' * num_spaces),
+ sys.stdout.flush()
+
+ if sys.stdout.isatty():
+ # stdout is a terminal; stupid backspace tricks are OK.
+ # Don't use print, because it always adds magical spaces, which
+ # makes backspace accounting harder
+
+ backspaces = [0]
+ def print_status(msg):
+ # Overwrite any status text with spaces before printing
+ sys.stdout.write('\b' * backspaces[0])
+ sys.stdout.write(' ' * backspaces[0])
+ sys.stdout.write('\b' * backspaces[0])
+ sys.stdout.write(msg)
+ sys.stdout.flush()
+ backspaces[0] = len(msg)
+
+ def print_done(msg='ok'):
+ # Overwrite any status text with spaces before printing
+ sys.stdout.write('\b' * backspaces[0])
+ sys.stdout.write(' ' * backspaces[0])
+ sys.stdout.write('\b' * backspaces[0])
+ sys.stdout.write(msg + "\n")
+ sys.stdout.flush()
+ backspaces[0] = 0
+
+ else:
+ # stdout is a file (or something); don't bother with status at all
+ def print_status(msg):
+ pass
+
+ def print_done(msg='ok'):
+ print msg
+
+ return print_start, print_status, print_done
+
+
+def load(session, tables=[], directory=None, drop_tables=False, verbose=False):
"""Load data from CSV files into the given database session.
Tables are created automatically.
`session`
SQLAlchemy session to use.
+ `tables`
+ List of tables to load. If omitted, all tables are loaded.
+
`directory`
Directory the CSV files reside in. Defaults to the `pokedex` data
directory.
`drop_tables`
If set to True, existing `pokedex`-related tables will be dropped.
+
+ `verbose`
+ If set to True, status messages will be printed to stdout.
"""
- if not directory:
- directory = pkg_resources.resource_filename('pokedex', 'data/csv')
+ # First take care of verbosity
+ print_start, print_status, print_done = _get_verbose_prints(verbose)
- # Drop all tables if requested
- if options.drop_tables:
- print 'Dropping tables...'
- metadata.drop_all()
- metadata.create_all()
+ if not directory:
+ directory = pkg_resources.resource_filename('pokedex', 'data/csv')
- # SQLAlchemy is retarded and there is no way for me to get a list of ORM
- # classes besides to inspect the module they all happen to live in for
- # things that look right.
- table_base = tables.TableBase
- orm_classes = {} # table object => table class
+ table_names = _get_table_names(metadata, tables)
+ table_objs = [metadata.tables[name] for name in table_names]
+ table_objs = sqlalchemy.sql.util.sort_tables(table_objs)
- for name in dir(tables):
- # dir() returns strings! How /convenient/.
- thingy = getattr(tables, name)
- if not isinstance(thingy, type):
- # Not a class; bail
- continue
- elif not issubclass(thingy, table_base):
- # Not a declarative table; bail
- continue
- elif thingy == table_base:
- # Declarative table base, so not a real table; bail
- continue
+ # Drop all tables if requested
+ if drop_tables:
+ print_start('Dropping tables')
+ for table in reversed(table_objs):
+ table.drop(checkfirst=True)
+ print_done()
- # thingy is definitely a table class! Hallelujah.
- orm_classes[thingy.__table__] = thingy
+ for table in table_objs:
+ table.create()
+ connection = session.connection()
# Okay, run through the tables and actually load the data now
- for table_obj in metadata.sorted_tables:
- table_class = orm_classes[table_obj]
+ for table_obj in table_objs:
table_name = table_obj.name
+ insert_stmt = table_obj.insert()
- # Print the table name but leave the cursor in a fixed column
- print table_name + '...', ' ' * (40 - len(table_name)),
- sys.stdout.flush()
+ print_start(table_name)
try:
- csvfile = open("%s/%s.csv" % (directory, table_name), 'rb')
+ csvpath = "%s/%s.csv" % (directory, table_name)
+ csvfile = open(csvpath, 'rb')
except IOError:
# File doesn't exist; don't load anything!
- print 'no data!'
+ print_done('missing?')
continue
+ csvsize = os.stat(csvpath).st_size
+
reader = csv.reader(csvfile, lineterminator='\n')
column_names = [unicode(column) for column in reader.next()]
if any(_.references(table_obj) for _ in column.foreign_keys):
self_ref_columns.append(column)
+ new_rows = []
+ def insert_and_commit():
+ session.connection().execute(insert_stmt, new_rows)
+ session.commit()
+ new_rows[:] = []
+
+ progress = "{0}%".format(100 * csvfile.tell() // csvsize)
+ print_status(progress)
+
for csvs in reader:
- row = table_class()
+ row_data = {}
for column_name, value in zip(column_names, csvs):
column = table_obj.c[column_name]
# Otherwise, unflatten from bytes
value = value.decode('utf-8')
- setattr(row, column_name, value)
+ # nb: Dictionaries flattened with ** have to have string keys
+ row_data[ str(column_name) ] = value
# May need to stash this row and add it later if it refers to a
# later row in this table
if self_ref_columns:
- foreign_ids = [getattr(row, _.name) for _ in self_ref_columns]
+ foreign_ids = [row_data[_.name] for _ in self_ref_columns]
foreign_ids = [_ for _ in foreign_ids if _] # remove NULL ids
if not foreign_ids:
# NULL key. Remember this row and add as usual.
- seen_ids[row.id] = 1
+ seen_ids[row_data['id']] = 1
elif all(_ in seen_ids for _ in foreign_ids):
# Non-NULL key we've already seen. Remember it and commit
# so we know the old row exists when we add the new one
- session.commit()
- seen_ids[row.id] = 1
+ insert_and_commit()
+ seen_ids[row_data['id']] = 1
else:
# Non-NULL future id. Save this and insert it later!
- deferred_rows.append((row, foreign_ids))
+ deferred_rows.append((row_data, foreign_ids))
continue
- session.add(row)
+ # Insert row!
+ new_rows.append(row_data)
- session.commit()
+ # Remembering some zillion rows in the session consumes a lot of
+ # RAM. Let's not do that. Commit every 1000 rows
+ if len(new_rows) >= 1000:
+ insert_and_commit()
+
+ insert_and_commit()
# Attempt to add any spare rows we've collected
- for row, foreign_ids in deferred_rows:
+ for row_data, foreign_ids in deferred_rows:
if not all(_ in seen_ids for _ in foreign_ids):
# Could happen if row A refers to B which refers to C.
# This is ridiculous and doesn't happen in my data so far
raise ValueError("Too many levels of self-reference! "
- "Row was: " + str(row.__dict__))
+ "Row was: " + str(row))
- session.add(row)
- seen_ids[row.id] = 1
- session.commit()
+ session.connection().execute(
+ insert_stmt.values(**row_data)
+ )
+ seen_ids[row_data['id']] = 1
+ session.commit()
- print 'loaded'
+ print_done()
-def dump(session, directory=None):
+def dump(session, tables=[], directory=None, verbose=False):
"""Dumps the contents of a database to a set of CSV files. Probably not
useful to anyone besides a developer.
`session`
SQLAlchemy session to use.
+ `tables`
+ List of tables to dump. If omitted, all tables are dumped.
+
`directory`
Directory the CSV files should be put in. Defaults to the `pokedex`
data directory.
+
+ `verbose`
+ If set to True, status messages will be printed to stdout.
"""
+ # First take care of verbosity
+ print_start, print_status, print_done = _get_verbose_prints(verbose)
+
+
if not directory:
directory = pkg_resources.resource_filename('pokedex', 'data/csv')
- for table_name in sorted(metadata.tables.keys()):
- print table_name
+ table_names = _get_table_names(metadata, tables)
+ table_names.sort()
+
+
+ for table_name in table_names:
+ print_start(table_name)
table = metadata.tables[table_name]
writer = csv.writer(open("%s/%s.csv" % (directory, table_name), 'wb'),
csvs.append(val)
writer.writerow(csvs)
+
+ print_done()
projects / zzz-pokedex.git / blobdiff