"""CSV to database or vice versa.""" import csv import fnmatch import os.path import sys import sqlalchemy.sql.util import sqlalchemy.types import pokedex from pokedex.db import metadata, tables, translations from pokedex.defaults import get_default_csv_dir from pokedex.db.dependencies import find_dependent_tables 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[: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, safe=True, recursive=True, langs=None): """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. `safe` If set to False, load can be faster, but can corrupt the database if it crashes or is interrupted. `recursive` If set to True, load all dependent tables too. `langs` List of identifiers of extra language to load, or None to load them all """ # First take care of verbosity print_start, print_status, print_done = _get_verbose_prints(verbose) if directory is None: directory = get_default_csv_dir() # XXX why isn't this done in command_load table_names = _get_table_names(metadata, tables) table_objs = [metadata.tables[name] for name in table_names] # Oracle fixery again, load doesn't know we modified the schema # flag for oracle stuff oranames = (session.connection().dialect.name == 'oracle') if oranames: # Prepare a dictionary to match old<->new names oradict = {} # Shorten table names, Oracle limits table and column names to 30 chars for table in table_objs: tname = table.name[:] oradict[tname]=table.description if len(tname) > 30: for letter in ['a', 'e', 'i', 'o', 'u', 'y']: table.name=table.name.replace(letter,'') oradict[tname]=table.description if recursive: table_objs.extend(find_dependent_tables(table_objs)) table_objs = sqlalchemy.sql.util.sort_tables(table_objs) # SQLite speed tweaks if not safe and session.connection().dialect.name == 'sqlite': session.connection().execute("PRAGMA synchronous=OFF") session.connection().execute("PRAGMA journal_mode=OFF") # Drop all tables if requested if drop_tables: bind = session.get_bind() print_start('Dropping tables') for n, table in enumerate(reversed(table_objs)): table.drop(checkfirst=True) # Drop columns' types if appropriate; needed for enums in # postgresql for column in table.c: try: drop = column.type.drop except AttributeError: pass else: drop(bind=bind, checkfirst=True) print_status('%s/%s' % (n, len(table_objs))) print_done() print_start('Creating tables') for n, table in enumerate(table_objs): table.create() print_status('%s/%s' % (n, len(table_objs))) print_done() connection = session.connection() # Okay, run through the tables and actually load the data now for table_obj in table_objs: table_name = table_obj.name insert_stmt = table_obj.insert() print_start(table_name) try: csvpath = "%s/%s.csv" % (directory, table_name) # In oracle mode, use the original names instead of current if oranames: csvpath = "%s/%s.csv" % (directory, oradict[table_name]) csvfile = open(csvpath, 'rb') except IOError: # File doesn't exist; don't load anything! 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 not safe and session.connection().dialect.name == 'postgresql': """ Postgres' CSV dialect works with our data, if we mark the not-null columns with FORCE NOT NULL. COPY is only allowed for DB superusers. If you're not one, use safe loading (pokedex load -S). """ session.commit() not_null_cols = [c for c in column_names if not table_obj.c[c].nullable] if not_null_cols: force_not_null = 'FORCE NOT NULL ' + ','.join('"%s"' % c for c in not_null_cols) else: force_not_null = '' command = "COPY %(table_name)s (%(columns)s) FROM '%(csvpath)s' CSV HEADER %(force_not_null)s" session.connection().execute( command % dict( table_name=table_name, csvpath=csvpath, columns=','.join('"%s"' % c for c in column_names), force_not_null=force_not_null, ) ) session.commit() print_done() continue # Self-referential tables may contain rows with foreign keys of other # rows in the same table that do not yet exist. Pull these out and add # them to the session last # ASSUMPTION: Self-referential tables have a single PK called "id" deferred_rows = [] # ( row referring to id, [foreign ids we need] ) seen_ids = set() # primary keys we've seen # Fetch foreign key columns that point at this table, if any self_ref_columns = [] for column in table_obj.c: if any(x.references(table_obj) for x in column.foreign_keys): self_ref_columns.append(column) new_rows = [] def insert_and_commit(): if not new_rows: return session.connection().execute(insert_stmt, new_rows) session.commit() new_rows[:] = [] progress = "%d%%" % (100 * csvfile.tell() // csvsize) print_status(progress) for csvs in reader: row_data = {} for column_name, value in zip(column_names, csvs): column = table_obj.c[column_name] # Oracle treats empty strings as NULL if not column.nullable and value == '' and oranames: value = ' ' if column.nullable and value == '': # Empty string in a nullable column really means NULL value = None elif isinstance(column.type, sqlalchemy.types.Boolean): # Boolean values are stored as string values 0/1, but both # of those evaluate as true; SQLA wants True/False if value == '0': value = False else: value = True else: # Otherwise, unflatten from bytes value = value.decode('utf-8') # 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 = set(row_data[x.name] for x in self_ref_columns) foreign_ids.discard(None) # remove NULL ids if not foreign_ids: # NULL key. Remember this row and add as usual. seen_ids.add(row_data['id']) elif foreign_ids.issubset(seen_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 insert_and_commit() seen_ids.add(row_data['id']) else: # Non-NULL future id. Save this and insert it later! deferred_rows.append((row_data, foreign_ids)) continue # Insert row! new_rows.append(row_data) # 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_data, foreign_ids in deferred_rows: if not foreign_ids.issubset(seen_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)) session.connection().execute( insert_stmt.values(**row_data) ) seen_ids.add(row_data['id']) session.commit() print_done() print_start('Translations') transl = translations.Translations(csv_directory=directory) new_row_count = 0 for translation_class, rows in transl.get_load_data(langs): table_obj = translation_class.__table__ if table_obj in table_objs: insert_stmt = table_obj.insert() session.connection().execute(insert_stmt, rows) session.commit() # We don't have a total, but at least show some increasing number new_row_count += len(rows) print_status(str(new_row_count)) print_done() # SQLite check if session.connection().dialect.name == 'sqlite': session.connection().execute("PRAGMA integrity_check") def dump(session, tables=[], directory=None, verbose=False, langs=['en']): """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. `langs` List of identifiers of languages to dump unofficial texts for """ # First take care of verbosity print_start, print_status, print_done = _get_verbose_prints(verbose) languages = dict((l.id, l) for l in session.query(pokedex.db.tables.Language)) if not directory: directory = get_default_csv_dir() 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'), lineterminator='\n') columns = [col.name for col in table.columns] # For name tables, dump rows for official languages, as well as # for those in `langs`. # For other translation tables, only dump rows for languages in `langs` # For non-translation tables, dump all rows. if 'local_language_id' in columns: if any(col.info.get('official') for col in table.columns): def include_row(row): return (languages[row.local_language_id].official or languages[row.local_language_id].identifier in langs) else: def include_row(row): return languages[row.local_language_id].identifier in langs else: def include_row(row): return True writer.writerow(columns) primary_key = table.primary_key for row in session.query(table).order_by(*primary_key).all(): if include_row(row): csvs = [] for col in columns: # Convert Pythony values to something more universal val = getattr(row, col) if val == None: val = '' elif val == True: val = '1' elif val == False: val = '0' else: val = unicode(val).encode('utf-8') csvs.append(val) writer.writerow(csvs) print_done()