def dump(session, tables=[], directory=None, verbose=False, langs=None): """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() # Oracle needs to dump from tables with shortened names to csvs with the # usual names oracle = (session.connection().dialect.name == 'oracle') if oracle: rewrite_long_table_names() for table_name in table_names: print_start(table_name) table = metadata.tables[table_name] if oracle: filename = '%s/%s.csv' % (directory, table._original_name) else: filename = '%s/%s.csv' % (directory, table_name) # CSV module only works with bytes on 2 and only works with text on 3! if six.PY3: writer = csv.writer(open(filename, 'w', newline=''), lineterminator='\n') columns = [col.name for col in table.columns] else: writer = csv.writer(open(filename, 'wb'), lineterminator='\n') columns = [col.name.encode('utf8') for col in table.columns] # For name tables, always dump rows for official languages, as well as # for those in `langs` if specified. # For other translation tables, only dump rows for languages in `langs` # if specified, or for official languages by default. # For non-translation tables, dump all rows. if 'local_language_id' in columns: if langs is None: def include_row(row): return languages[row.local_language_id].official elif 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 = six.text_type(val) if not six.PY3: val = val.encode('utf8') csvs.append(val) writer.writerow(csvs) 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] if recursive: table_objs.extend(find_dependent_tables(table_objs)) table_objs = sqlalchemy.sql.util.sort_tables(table_objs) # Limit table names to 30 characters for Oracle oracle = (session.connection().dialect.name == 'oracle') if oracle: rewrite_long_table_names() # 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: if oracle: table_name = table_obj._original_name else: table_name = table_obj.name insert_stmt = table_obj.insert() print_start(table_name) try: csvpath = "%s/%s.csv" % (directory, 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] 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 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] if recursive: table_objs.extend(find_dependent_tables(table_objs)) table_objs = sqlalchemy.sql.util.sort_tables(table_objs) engine = session.get_bind() # Limit table names to 30 characters for Oracle oracle = (engine.dialect.name == 'oracle') if oracle: rewrite_long_table_names() # SQLite speed tweaks if not safe and engine.dialect.name == 'sqlite': session.execute("PRAGMA synchronous=OFF") session.execute("PRAGMA journal_mode=OFF") # Drop all tables if requested if drop_tables: print_start('Dropping tables') for n, table in enumerate(reversed(table_objs)): table.drop(bind=engine, 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=engine, 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() # Okay, run through the tables and actually load the data now for table_obj in table_objs: if oracle: table_name = table_obj._original_name else: table_name = table_obj.name insert_stmt = table_obj.insert() print_start(table_name) try: csvpath = "%s/%s.csv" % (directory, table_name) csvfile = open(csvpath, 'r') except IOError: # File doesn't exist; don't load anything! print_done('missing?') continue # XXX This is wrong for files with multi-line fields, but Python 3 # doesn't allow .tell() on a file that's currently being iterated # (because the result is completely bogus). Oh well. csvsize = sum(1 for line in csvfile) csvfile.seek(0) reader = csv.reader(csvfile, lineterminator='\n') column_names = [six.text_type(column) for column in next(reader)] if not safe and engine.dialect.name == 'postgresql': # Postgres' CSV dialect works with our data, if we mark the not-null # columns with FORCE NOT NULL. 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 = '' # Grab the underlying psycopg2 cursor so we can use COPY FROM STDIN raw_conn = engine.raw_connection() command = "COPY %(table_name)s (%(columns)s) FROM STDIN CSV HEADER %(force_not_null)s" csvfile.seek(0) raw_conn.cursor().copy_expert( command % dict( table_name=table_name, columns=','.join('"%s"' % c for c in column_names), force_not_null=force_not_null, ), csvfile, ) raw_conn.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 # insert them 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.execute(insert_stmt, new_rows) session.commit() new_rows[:] = [] progress = "%d%%" % (100 * csvpos // csvsize) print_status(progress) csvpos = 0 for csvs in reader: csvpos += 1 row_data = {} for column_name, value in zip(column_names, csvs): column = table_obj.c[column_name] 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 elif isinstance(value, bytes): # 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.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.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)) # SQLite check if engine.dialect.name == 'sqlite': session.execute("PRAGMA integrity_check") print_done()
def dump(session, tables=[], directory=None, verbose=False, langs=None): """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() # Oracle needs to dump from tables with shortened names to csvs with the # usual names oracle = (session.connection().dialect.name == 'oracle') if oracle: rewrite_long_table_names() for table_name in table_names: print_start(table_name) table = metadata.tables[table_name] if oracle: filename = '%s/%s.csv' % (directory, table._original_name) else: filename = '%s/%s.csv' % (directory, table_name) writer = csv.writer(open(filename, 'wb'), lineterminator='\n') columns = [col.name for col in table.columns] # For name tables, always dump rows for official languages, as well as # for those in `langs` if specified. # For other translation tables, only dump rows for languages in `langs` # if specified, or for official languages by default. # For non-translation tables, dump all rows. if 'local_language_id' in columns: if langs is None: def include_row(row): return languages[row.local_language_id].official elif 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()