pyCDB reference¶

pyCDB.client¶

pyCDB.DAQClient¶

pyCDB.pyCDBBase¶

Created on Jun 13, 2012

@author: jurban

exception pyCDB.pyCDBBase.CDBException¶: A generic CDB exception class

class pyCDB.pyCDBBase.OrderedDict(*args, **kwargs)¶

Customized ordered dictionary

diff(other, mode='norm')¶

Find differences to another OrderedDict, ignoring the keys order

Parameters:	other – OrderedDict object to compare to

classmethod load_h5(filename)¶

Deserialize from an HDF5 file (created by save_h5)

Parameters:	filename – input file name

save_h5(filename, mode='w')¶

Serialize to an HDF5 file

Parameters:	filename – output file name mode – file open mode, typically ‘w’ or ‘a’

pyCDB.pyCDBBase.cdb_base_check(func)¶

Basic checking (database connection in particular) before calling CDB functions.

To be used as decorator for client methods. Raises an exception if problem occurs.

pyCDB.pyCDBBase.isintlike(obj)¶

Is object int-like?

In Python 2, this means int or long. In Python 3, this means just int.

pyCDB.pyCDBBase.isstringlike(obj)¶

Is object string-like?

In Python 2, this means string or unicode. In Python 3, this means just string.

class pyCDB.pyCDBBase.pyCDBBase(host=None, user=None, passwd=None, db=None, port=3306, log_level=None, data_root=None)¶

PyCDB base class for other pyCDB classes

check_connection(reconnect=True)¶: Checks if connection is open, optionally (re)connects.

close()¶: Close all connections (SQL)

cursor¶: cursor from self.db

db¶

Connection to the database.

each thread has its local connection
connection is automatically opened

delete(table_name, fields)¶

Delete a row from the table.

Parameters:	table_name – name of table to insert to fields – dictionary of fields identifying the row

Deletes at most one row: First, it checks for its existence in the table. If more than one row is found, raises exception. Returns True is something was deleted, False if not.

error(exception)¶

Log an error and throw the exception

Parameters:	exception – can be an exception or string with the message.

file_log_level¶: Get logging level

classmethod filter_sql_str(sql_str, extra_chars='_', quiet=False)¶

Filter a string intended to be stored to SQL

Parameters:	sql_str – input string

Keep only white listed characters: letters, digits, _.

classmethod format_file_name(collection_name, revision, file_format='HDF5', file_extension=None)¶: Returns generic file name

classmethod get_conf_value(var_name, section='database', required=False)¶

Get configuration value for a given variable name

First looks for environment variables, then to ./.CDBrc, then to ~/.CDBrc

Parameters:	var_name – one of CDB_HOST, CDB_USER, CDB_PASSWD, CDB_DB required – if True, exception is raised telling the user that he/she has to set the option.
Return type:	variable value

get_file_log_level()¶: Get logging level

get_log_level()¶: Get logging level

get_table_struct(table_name)¶: Get a table structure (as a dict)

insert(table_name, fields, return_inserted_id=False, check_structure=True)¶

Insert a new row to a table.

Parameters:	table_name – name of table to insert to fields – dictionary of ( field name, value ) to insert return_inserted_id – if true, returns the id of the inserted row check_structure – if true, checks, whether fields agree with table layout,

Values are processed to be DB-friendly by mysql_values (see).

classmethod is_json(text)¶

Checks whether text has a valid JSON syntax

Parameters:	text – text (string) to check

log_level¶: Get logging level

classmethod makedirs(path[, mode=2047])¶: Super-mkdir; create a leaf directory and all intermediate ones. Works like mkdir, except that any intermediate path segment (not just the rightmost) will be created if it does not exist. This is recursive.

classmethod mysql_str(val, float_format='%.17g', datetime_format='%Y-%m-%d %H:%M:%S', quote=True)¶

Convert Python value into MySQL string and quote if necessary

Use as the first character of MySQL builtin functions to avoid quoting

Lists and tuples are converted into parentheses-wrapped lists (using recursion) to work with IN operator.

classmethod mysql_values(val_list, float_format='%.17g', datetime_format='%Y-%m-%d %H:%M:%S', quote=True)¶: Construct whole VALUES MySQL INSERT construct for a list of Python values

query(sql, error_if_empty=False, warn_if_empty=False, error_if_multiple=False)¶

Execute SQL query and returns a list of rows as dictionaries.

Parameters:	sql – valid SQL query error_if_empty – raises exception if the result set is empty warn_if_empty – issues warning if the result set is empty but successfully returns it error_if_multiple – the result has to include at maximum 1 row

classmethod row_as_dict(row, description)¶: Convert SQL row tuple to python dict

set_file_log_level(value)¶: Set logging level

set_log_level(value)¶: Set logging level

classmethod sql_to_python_type(sql_type_str)¶: Transforms MySQL type definition to Python type and its length

update(table_name, id_field, id_value, fields)¶

Update a row in a table.

Parameters:	table_name – name of table to insert to id_field – name of the unique key field id_value – value of the unique key fields – dictionary of ( field name, value ) to insert

pyCDB.logbook¶