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# IVLE - Informatics Virtual Learning Environment
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# Copyright (C) 2007-2008 The University of Melbourne
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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# Code to talk to the PostgreSQL database.
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# (This is the Data Access Layer).
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# All DB code should be in this module to ensure portability if we want to
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# change the DB implementation.
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# This means no SQL strings should be outside of this module. Add functions
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# here to perform the activities needed, and place the SQL code for those
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# CAUTION to editors of this module.
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# All string inputs must be sanitized by calling _escape before being
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# formatted into an SQL query string.
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from ivle import (caps, user)
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TIMESTAMP_FORMAT = '%Y-%m-%d %H:%M:%S'
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"""Wrapper around pg.escape_string. Prepares the Python value for use in
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SQL. Returns a string, which may be safely placed verbatim into an SQL
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Handles the following types:
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* str: Escapes the string, and also quotes it.
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* int/long/float: Just converts to an unquoted string.
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* bool: Returns as "TRUE" or "FALSE", unquoted.
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* NoneType: Returns "NULL", unquoted.
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* common.caps.Role: Returns the role as a quoted, lowercase string.
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* time.struct_time: Returns the time as a quoted string for insertion into
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Raises a DBException if val has an unsupported type.
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# "E'" is postgres's way of making "escape" strings.
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# Such strings allow backslashes to escape things. Since escape_string
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# converts a single backslash into two backslashes, it needs to be fed
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# Ref: http://www.postgresql.org/docs/8.2/static/sql-syntax-lexical.html
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# WARNING: PostgreSQL-specific code
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elif isinstance(val, str) or isinstance(val, unicode):
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return "E'" + pg.escape_string(val) + "'"
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elif isinstance(val, bool):
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return "TRUE" if val else "FALSE"
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elif isinstance(val, int) or isinstance(val, long) \
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or isinstance(val, float):
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elif isinstance(val, caps.Role):
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return _escape(str(val))
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elif isinstance(val, time.struct_time):
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return _escape(time.strftime(TIMESTAMP_FORMAT, val))
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raise DBException("Attempt to insert an unsupported type "
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"into the database (%s)" % repr(type(val)))
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def _parse_boolean(val):
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Accepts a boolean as output from the DB (either the string 't' or 'f').
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Returns a boolean value True or False.
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Also accepts other values which mean True or False in PostgreSQL.
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If none match, raises a DBException.
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# On a personal note, what sort of a language allows 7 different values
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# to denote each of True and False?? (A: SQL)
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if isinstance(val, bool):
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elif val == 'true' or val == 'y' or val == 'yes' or val == '1' \
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elif val == 'false' or val == 'n' or val == 'no' or val == '0' \
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raise DBException("Invalid boolean value returned from DB")
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def _passhash(password):
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return md5.md5(password).hexdigest()
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class DBException(Exception):
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"""A DBException is for bad conditions in the database or bad input to
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these methods. If Postgres throws an exception it does not get rebadged.
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This is only for additional exceptions."""
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"""An IVLE database object. This object provides an interface to
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interacting with the IVLE database without using any external SQL.
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Most methods of this class have an optional dry argument. If true, they
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will return the SQL query string and NOT actually execute it. (For
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Methods may throw db.DBException, or any of the pg exceptions as well.
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(In general, be prepared to catch exceptions!)
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"""Connects to the database and creates a DB object.
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Takes no parameters - gets all the DB info from the configuration."""
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self.db = pg.connect(host=ivle.conf.db_host, port=ivle.conf.db_port,
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dbname=ivle.conf.db_dbname,
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user=ivle.conf.db_user, passwd=ivle.conf.db_password)
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# GENERIC DB FUNCTIONS #
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def check_dict(dict, tablefields, disallowed=frozenset([]), must=False):
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"""Checks that a dict does not contain keys that are not fields
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of the specified table.
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dict: A mapping from string keys to values; the keys are checked to
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see that they correspond to login table fields.
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tablefields: Collection of strings for field names in the table.
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Only these fields will be allowed.
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disallowed: Optional collection of strings for field names that are
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must: If True, the dict MUST contain all fields in tablefields.
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If False, it may contain any subset of the fields.
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Returns True if the dict is valid, False otherwise.
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allowed = frozenset(tablefields) - frozenset(disallowed)
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dictkeys = frozenset(dict.keys())
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return allowed == dictkeys
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return allowed.issuperset(dictkeys)
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def insert(self, dict, tablename, tablefields, disallowed=frozenset([]),
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"""Inserts a new row in a table, using data from a supplied
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dictionary (which will be checked by check_dict).
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dict: Dictionary mapping column names to values. The values may be
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any of the following types:
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str, int, long, float, NoneType.
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tablename: String, name of the table to insert into. Will NOT be
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escaped - must be a valid identifier.
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tablefields, disallowed: see check_dict.
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dry: Returns the SQL query as a string, and does not execute it.
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Raises a DBException if the dictionary contains invalid fields.
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if not DB.check_dict(dict, tablefields, disallowed):
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extras = set(dict.keys()) - tablefields
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raise DBException("Supplied dictionary contains invalid fields. (%s)" % (repr(extras)))
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# Build two lists concurrently: field names and values, as SQL strings
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for k,v in dict.items():
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values.append(_escape(v))
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if len(fieldnames) == 0: return
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fieldnames = ', '.join(fieldnames)
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values = ', '.join(values)
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query = ("INSERT INTO %s (%s) VALUES (%s);"
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% (tablename, fieldnames, values))
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def return_insert(self, dict, tablename, tablefields, returning,
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disallowed=frozenset([]), dry=False):
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"""Inserts a new row in a table, using data from a supplied
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dictionary (which will be checked by check_dict) and returns certain
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dict: Dictionary mapping column names to values. The values may be
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any of the following types:
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str, int, long, float, NoneType.
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tablename: String, name of the table to insert into. Will NOT be
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escaped - must be a valid identifier.
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returning: List of fields to return, not escaped
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tablefields, disallowed: see check_dict.
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dry: Returns the SQL query as a string, and does not execute it.
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Raises a DBException if the dictionary contains invalid fields.
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if not DB.check_dict(dict, tablefields, disallowed):
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extras = set(dict.keys()) - tablefields
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raise DBException("Supplied dictionary contains invalid fields. (%s)" % (repr(extras)))
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# Build two lists concurrently: field names and values, as SQL strings
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for k,v in dict.items():
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values.append(_escape(v))
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if len(fieldnames) == 0: return
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fieldnames = ', '.join(fieldnames)
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values = ', '.join(values)
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returns = ', '.join(returning)
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query = ("INSERT INTO %s (%s) VALUES (%s) RETURNING (%s);"
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% (tablename, fieldnames, values, returns))
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return self.db.query(query)
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def update(self, primarydict, updatedict, tablename, tablefields,
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primary_keys, disallowed_update=frozenset([]), dry=False):
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"""Updates a row in a table, matching against primarydict to find the
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row, and using the data in updatedict (which will be checked by
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primarydict: Dict mapping column names to values. The keys should be
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the table's primary key. Only rows which match this dict's values
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updatedict: Dict mapping column names to values. The columns will be
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updated with the given values for the matched rows.
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tablename, tablefields, disallowed_update: See insert.
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primary_keys: Collection of strings which together form the primary
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key for this table. primarydict must contain all of these as keys,
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if (not (DB.check_dict(primarydict, primary_keys, must=True)
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and DB.check_dict(updatedict, tablefields, disallowed_update))):
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raise DBException("Supplied dictionary contains invalid or missing fields (1).")
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# Make a list of SQL fragments of the form "field = 'new value'"
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# These fragments are ALREADY-ESCAPED
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for k,v in updatedict.items():
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setlist.append("%s = %s" % (k, _escape(v)))
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for k,v in primarydict.items():
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wherelist.append("%s = %s" % (k, _escape(v)))
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if len(setlist) == 0 or len(wherelist) == 0:
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# Join the fragments into a comma-separated string
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setstring = ', '.join(setlist)
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wherestring = ' AND '.join(wherelist)
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# Build the whole query as an UPDATE statement
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query = ("UPDATE %s SET %s WHERE %s;"
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% (tablename, setstring, wherestring))
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def delete(self, primarydict, tablename, primary_keys, dry=False):
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"""Deletes a row in the table, matching against primarydict to find
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primarydict, tablename, primary_keys: See update.
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if not DB.check_dict(primarydict, primary_keys, must=True):
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raise DBException("Supplied dictionary contains invalid or missing fields (2).")
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for k,v in primarydict.items():
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wherelist.append("%s = %s" % (k, _escape(v)))
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if len(wherelist) == 0:
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wherestring = ' AND '.join(wherelist)
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query = ("DELETE FROM %s WHERE %s;" % (tablename, wherestring))
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def get_single(self, primarydict, tablename, getfields, primary_keys,
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error_notfound="No rows found", dry=False):
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"""Retrieves a single row from a table, returning it as a dictionary
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mapping field names to values. Matches against primarydict to find the
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primarydict, tablename, primary_keys: See update/delete.
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getfields: Collection of strings; the field names which will be
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returned as keys in the dictionary.
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error_notfound: Error message if 0 rows match.
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Raises a DBException if 0 rows match, with error_notfound as the msg.
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Raises an AssertError if >1 rows match (this should not happen if
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primary_keys is indeed the primary key).
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if not DB.check_dict(primarydict, primary_keys, must=True):
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raise DBException("Supplied dictionary contains invalid or missing fields (3).")
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for k,v in primarydict.items():
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wherelist.append("%s = %s" % (k, _escape(v)))
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if len(getfields) == 0 or len(wherelist) == 0:
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# Join the fragments into a comma-separated string
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getstring = ', '.join(getfields)
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wherestring = ' AND '.join(wherelist)
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# Build the whole query as an SELECT statement
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query = ("SELECT %s FROM %s WHERE %s;"
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% (getstring, tablename, wherestring))
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result = self.db.query(query)
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# Expecting exactly one
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if result.ntuples() != 1:
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# It should not be possible for ntuples to be greater than 1
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assert (result.ntuples() < 1)
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raise DBException(error_notfound)
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# Return as a dictionary
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return result.dictresult()[0]
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def get_all(self, tablename, getfields, dry=False):
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"""Retrieves all rows from a table, returning it as a list of
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dictionaries mapping field names to values.
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tablename, getfields: See get_single.
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if len(getfields) == 0:
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getstring = ', '.join(getfields)
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query = ("SELECT %s FROM %s;" % (getstring, tablename))
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return self.db.query(query).dictresult()
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def start_transaction(self, dry=False):
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"""Starts a DB transaction.
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Will not commit any changes until self.commit() is called.
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query = "START TRANSACTION;"
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def commit(self, dry=False):
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"""Commits (ends) a DB transaction.
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Commits all changes since the call to start_transaction.
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def rollback(self, dry=False):
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"""Rolls back (ends) a DB transaction, undoing all changes since the
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call to start_transaction.
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# USER MANAGEMENT FUNCTIONS #
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login_primary = frozenset(["login"])
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login_fields_list = [
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"login", "passhash", "state", "unixid", "email", "nick", "fullname",
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"rolenm", "studentid", "acct_exp", "pass_exp", "last_login", "svn_pass"
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login_fields = frozenset(login_fields_list)
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def create_user(self, user_obj=None, dry=False, **kwargs):
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"""Creates a user login entry in the database.
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Two ways to call this - passing a user object, or passing
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all fields as separate arguments.
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Either pass a "user_obj" as the first argument (in which case other
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fields will be ignored), or pass all fields as arguments.
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All user fields are to be passed as args. The argument names
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are the field names of the "login" table of the DB schema.
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However, instead of supplying a "passhash", you must supply a
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"password" argument, which will be hashed internally.
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Also "state" must not given explicitly; it is implicitly set to
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Raises an exception if the user already exists, or the dict contains
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invalid keys or is missing required keys.
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if 'passhash' in kwargs:
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raise DBException("Supplied arguments include passhash (invalid) (1).")
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# Make a copy of the dict. Change password to passhash (hashing it),
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# and set 'state' to "no_agreement".
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fields = copy.copy(kwargs)
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# Use the user object
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fields = dict(user_obj)
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if 'password' in fields:
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fields['passhash'] = _passhash(fields['password'])
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del fields['password']
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# Convert role to rolenm
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fields['rolenm'] = str(user_obj.role)
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fields['state'] = "no_agreement"
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# else, we'll trust the user, but it SHOULD be "no_agreement"
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# (We can't change it because then the user object would not
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if 'local_password' in fields:
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del fields['local_password']
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return self.insert(fields, "login", self.login_fields, dry=dry)
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def update_user(self, login, dry=False, **kwargs):
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"""Updates fields of a particular user. login is the name of the user
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to update. The dict contains the fields which will be modified, and
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their new values. If any value is omitted from the dict, it does not
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get modified. login and studentid may not be modified.
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Passhash may be modified by supplying a "password" field, in
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cleartext, not a hashed password.
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Note that no checking is done. It is expected this function is called
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by a trusted source. In particular, it allows the password to be
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changed without knowing the old password. The caller should check
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that the user knows the existing password before calling this function
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if 'passhash' in kwargs:
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raise DBException("Supplied arguments include passhash (invalid) (2).")
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if "password" in kwargs:
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kwargs = copy.copy(kwargs)
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kwargs['passhash'] = _passhash(kwargs['password'])
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del kwargs['password']
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return self.update({"login": login}, kwargs, "login",
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self.login_fields, self.login_primary, ["login", "studentid"],
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def get_user(self, login, dry=False):
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"""Given a login, returns a User object containing details looked up
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Raises a DBException if the login is not found in the DB.
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userdict = self.get_single({"login": login}, "login",
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self.login_fields, self.login_primary,
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error_notfound="get_user: No user with that login name", dry=dry)
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return userdict # Query string
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# Package into a User object
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return user.User(**userdict)
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def get_users(self, dry=False):
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"""Returns a list of all users in the DB, as User objects.
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userdicts = self.get_all("login", self.login_fields, dry=dry)
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return userdicts # Query string
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# Package into User objects
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return [user.User(**userdict) for userdict in userdicts]
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def get_user_loginid(self, login, dry=False):
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"""Given a login, returns the integer loginid for this user.
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Raises a DBException if the login is not found in the DB.
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userdict = self.get_single({"login": login}, "login",
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['loginid'], self.login_primary,
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error_notfound="get_user_loginid: No user with that login name",
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return userdict # Query string
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return userdict['loginid']
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def user_authenticate(self, login, password, dry=False):
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"""Performs a password authentication on a user. Returns True if
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"passhash" is the correct passhash for the given login, False
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if the passhash does not match the password in the DB,
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and None if the passhash in the DB is NULL.
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Also returns False if the login does not exist (so if you want to
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differentiate these cases, use get_user and catch an exception).
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query = ("SELECT passhash FROM login WHERE login = %s;"
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result = self.db.query(query)
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if result.ntuples() == 1:
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# Valid username. Check password.
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passhash = result.getresult()[0][0]
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return _passhash(password) == passhash
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# PROBLEM AND PROBLEM ATTEMPT FUNCTIONS #
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def get_problem_problemid(self, exercisename, dry=False):
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"""Given an exercise name, returns the associated problemID.
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If the exercise name is NOT in the database, it inserts it and returns
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the new problemID. Hence this may mutate the DB, but is idempotent.
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d = self.get_single({"identifier": exercisename}, "problem",
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['problemid'], frozenset(["identifier"]),
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return d # Query string
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# Shouldn't try again, must have failed for some other reason
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# if we failed to get a problemid, it was probably because
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# the exercise wasn't in the db. So lets insert it!
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# The insert can fail if someone else simultaneously does
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# the insert, so if the insert fails, we ignore the problem.
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self.insert({'identifier': exercisename}, "problem",
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frozenset(['identifier']))
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# Assuming the insert succeeded, we should be able to get the
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d = self.get_single({"identifier": exercisename}, "problem",
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['problemid'], frozenset(["identifier"]))
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return d['problemid']
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def insert_problem_attempt(self, login, exercisename, date, complete,
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"""Inserts the details of a problem attempt into the database.
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exercisename: Name of the exercise. (identifier field of problem
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table). If this exercise does not exist, also creates a new row in
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the problem table for this exercise name.
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login: Name of the user submitting the attempt. (login field of the
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date: struct_time, the date this attempt was made.
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complete: bool. Whether the test passed or not.
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attempt: Text of the attempt.
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Note: Even if dry, will still physically call get_problem_problemid,
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which may mutate the DB, and get_user_loginid, which may fail.
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problemid = self.get_problem_problemid(exercisename)
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loginid = self.get_user_loginid(login) # May raise a DBException
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'problemid': problemid,
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'complete': complete,
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}, 'problem_attempt',
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frozenset(['problemid','loginid','date','complete','attempt']),
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def write_problem_save(self, login, exercisename, date, text, dry=False):
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"""Writes text to the problem_save table (for when the user saves an
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exercise). Creates a new row, or overwrites an existing one if the
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user has already saved that problem.
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(Unlike problem_attempt, does not keep historical records).
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problemid = self.get_problem_problemid(exercisename)
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loginid = self.get_user_loginid(login) # May raise a DBException
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'problemid': problemid,
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frozenset(['problemid','loginid','date','text']),
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except pg.ProgrammingError:
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# May have failed because this problemid/loginid row already
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# exists (they have a unique key constraint).
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# Do an update instead.
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# Shouldn't try again, must have failed for some other reason
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'problemid': problemid,
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frozenset(['date', 'text']),
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frozenset(['problemid', 'loginid']))
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def get_problem_stored_text(self, login, exercisename, dry=False):
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"""Given a login name and exercise name, returns the text of the
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last saved/submitted attempt for this question.
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Returns None if the user has not saved or made an attempt on this
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(If the user has both saved and submitted, it returns whichever was
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Note: Even if dry, will still physically call get_problem_problemid,
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which may mutate the DB, and get_user_loginid, which may fail.
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problemid = self.get_problem_problemid(exercisename)
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loginid = self.get_user_loginid(login) # May raise a DBException
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# This very complex query finds all submissions made by this user for
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# this problem, as well as the save made by this user for this
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# problem, and returns the text of the newest one.
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# (Whichever is newer out of the save or the submit).
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query = """SELECT text FROM
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(SELECT * FROM problem_save WHERE loginid = %d AND problemid = %d)
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(SELECT problemid, loginid, date, text FROM problem_attempt
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AS problem_attempt (problemid, loginid, date, text)
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WHERE loginid = %d AND problemid = %d AND active)
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LIMIT 1;""" % (loginid, problemid, loginid, problemid)
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result = self.db.query(query)
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if result.ntuples() == 1:
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# The user has made at least 1 attempt. Return the newest.
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return result.getresult()[0][0]
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def get_problem_attempts(self, login, exercisename, allow_inactive=True,
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"""Given a login name and exercise name, returns a list of dicts, one
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for each attempt made for that exercise.
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Dicts are {'date': 'formatted_time', 'complete': bool}.
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Ordered with the newest first.
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Note: By default, returns de-activated problem attempts (unlike
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get_problem_stored_text).
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If allow_inactive is False, will not return disabled attempts.
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Note: Even if dry, will still physically call get_problem_problemid,
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which may mutate the DB, and get_user_loginid, which may fail.
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problemid = self.get_problem_problemid(exercisename)
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loginid = self.get_user_loginid(login) # May raise a DBException
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andactive = '' if allow_inactive else ' AND active'
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query = """SELECT date, complete FROM problem_attempt
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WHERE loginid = %d AND problemid = %d%s
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ORDER BY date DESC;""" % (loginid, problemid, andactive)
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result = self.db.query(query).getresult()
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# Make into dicts (could use dictresult, but want to convert values)
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return [{'date': date, 'complete': _parse_boolean(complete)}
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for date, complete in result]
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def get_problem_attempt(self, login, exercisename, as_of,
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allow_inactive=True, dry=False):
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"""Given a login name, exercise name, and struct_time, returns the
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text of the submitted attempt for this question as of that date.
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Returns None if the user had not made an attempt on this problem at
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Note: By default, returns de-activated problem attempts (unlike
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get_problem_stored_text).
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If allow_inactive is False, will not return disabled attempts.
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Note: Even if dry, will still physically call get_problem_problemid,
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which may mutate the DB, and get_user_loginid, which may fail.
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problemid = self.get_problem_problemid(exercisename)
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loginid = self.get_user_loginid(login) # May raise a DBException
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# Very similar to query in get_problem_stored_text, but without
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# looking in problem_save, and restricting to a certain date.
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andactive = '' if allow_inactive else ' AND active'
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query = """SELECT attempt FROM problem_attempt
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WHERE loginid = %d AND problemid = %d%s AND date <= %s
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LIMIT 1;""" % (loginid, problemid, andactive, _escape(as_of))
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result = self.db.query(query)
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if result.ntuples() == 1:
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# The user has made at least 1 attempt. Return the newest.
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return result.getresult()[0][0]
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def get_problem_status(self, login, exercisename, dry=False):
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"""Given a login name and exercise name, returns information about the
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user's performance on that problem.
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- A boolean, whether they have successfully passed this exercise.
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- An int, the number of attempts they have made up to and
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including the first successful attempt (or the total number of
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attempts, if not yet successful).
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Note: exercisename may be an int, in which case it will be directly
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used as the problemid.
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if isinstance(exercisename, int):
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problemid = exercisename
691
problemid = self.get_problem_problemid(exercisename)
692
loginid = self.get_user_loginid(login) # May raise a DBException
694
# ASSUME that it is completed, get the total number of attempts up to
695
# and including the first successful attempt.
696
# (Get the date of the first successful attempt. Then count the number
697
# of attempts made <= that date).
698
# Will return an empty table if the problem has never been
699
# successfully completed.
700
query = """SELECT COUNT(*) FROM problem_attempt
701
WHERE loginid = %d AND problemid = %d AND active AND date <=
702
(SELECT date FROM problem_attempt
703
WHERE loginid = %d AND problemid = %d AND complete AND active
705
LIMIT 1);""" % (loginid, problemid, loginid, problemid)
707
result = self.db.query(query)
708
count = int(result.getresult()[0][0])
710
# The user has made at least 1 successful attempt.
711
# Return True for success, and the number of attempts up to and
712
# including the successful one.
715
# Returned 0 rows - this indicates that the problem has not been
717
# Return the total number of attempts, and False for success.
718
query = """SELECT COUNT(*) FROM problem_attempt
719
WHERE loginid = %d AND problemid = %d AND active;""" % (loginid, problemid)
720
result = self.db.query(query)
721
count = int(result.getresult()[0][0])
722
return (False, count)
724
# WORKSHEET/PROBLEM ASSOCIATION AND MARKS CALCULATION
726
def get_worksheet_mtime(self, subject, worksheet, dry=False):
728
For a given subject/worksheet name, gets the time the worksheet was
729
last updated in the DB, if any.
730
This can be used to check if there is a newer version on disk.
731
Returns the timestamp as a time.struct_time, or None if the worksheet
732
is not found or has no stored mtime.
736
{"subject": subject, "identifier": worksheet},
737
"worksheet", ["mtime"], ["subject", "identifier"],
740
# Assume the worksheet is not in the DB
744
if r["mtime"] is None:
746
return time.strptime(r["mtime"], TIMESTAMP_FORMAT)
748
def create_worksheet(self, subject, worksheet, problems=None,
751
Inserts or updates rows in the worksheet and worksheet_problems
752
tables, to create a worksheet in the database.
753
This atomically performs all operations. If the worksheet is already
754
in the DB, removes it and all its associated problems and rebuilds.
755
Sets the timestamp to the current time.
757
problems is a collection of pairs. The first element of the pair is
758
the problem identifier ("identifier" column of the problem table). The
759
second element is an optional boolean, "optional". This can be omitted
760
(so it's a 1-tuple), and then it will default to False.
762
Problems and assessable are optional, and if omitted, will not change
763
the existing data. If the worksheet does not yet exist, and assessable
764
is omitted, it defaults to False.
766
Note: As with get_problem_problemid, if a problem name is not in the
767
DB, it will be added to the problem table.
769
self.start_transaction()
771
# Use the current time as the "mtime" field
772
mtime = time.localtime()
774
# Get the worksheetid
776
{"subject": subject, "identifier": worksheet},
777
"worksheet", ["worksheetid"], ["subject", "identifier"])
778
worksheetid = r["worksheetid"]
780
# Delete any problems which might exist, if problems is
781
# supplied. If it isn't, keep the existing ones.
782
if problems is not None:
783
query = ("DELETE FROM worksheet_problem "
784
"WHERE worksheetid = %d;" % worksheetid)
786
# Update the row with the new details
787
if assessable is None:
788
query = ("UPDATE worksheet "
789
"SET mtime = %s WHERE worksheetid = %d;"
790
% (_escape(mtime), worksheetid))
792
query = ("UPDATE worksheet "
793
"SET assessable = %s, mtime = %s "
794
"WHERE worksheetid = %d;"
795
% (_escape(assessable), _escape(mtime), worksheetid))
798
# Assume the worksheet is not in the DB
799
# If assessable is not supplied, default to False.
800
if assessable is None:
802
# Create the worksheet row
803
query = ("INSERT INTO worksheet "
804
"(subject, identifier, assessable, mtime) "
805
"VALUES (%s, %s, %s, %s);"""
806
% (_escape(subject), _escape(worksheet),
807
_escape(assessable), _escape(mtime)))
809
# Now get the worksheetid again - should succeed
811
{"subject": subject, "identifier": worksheet},
812
"worksheet", ["worksheetid"], ["subject", "identifier"])
813
worksheetid = r["worksheetid"]
815
# Now insert each problem into the worksheet_problem table
816
if problems is not None:
817
for problem in problems:
818
if isinstance(problem, tuple):
819
prob_identifier = problem[0]
821
optional = problem[1]
825
prob_identifier = problem
827
problemid = self.get_problem_problemid(prob_identifier)
828
query = ("INSERT INTO worksheet_problem "
829
"(worksheetid, problemid, optional) "
830
"VALUES (%d, %d, %s);"
831
% (worksheetid, problemid, _escape(optional)))
839
def set_worksheet_assessable(self, subject, worksheet, assessable,
842
Sets the "assessable" field of a worksheet without updating the mtime.
844
IMPORTANT: This will NOT update the mtime. This is designed to allow
845
updates which did not come from the worksheet XML file. It would be
846
bad to update the mtime without consulting the XML file because then
847
it would appear the database is up to date, when it isn't.
849
Therefore, call this method if you are getting "assessable"
850
information from outside the worksheet XML file (eg. from the subject
853
Unlike create_worksheet, raises a DBException if the worksheet is not
856
return self.update({"subject": subject, "identifier": worksheet},
857
{"assessable": assessable}, "worksheet", ["assessable"],
858
["subject", "identifier"], dry=dry)
860
def worksheet_is_assessable(self, subject, worksheet, dry=False):
862
{"subject": subject, "identifier": worksheet},
863
"worksheet", ["assessable"], ["subject", "identifier"], dry=dry)
864
return _parse_boolean(r["assessable"])
866
def calculate_score_worksheet(self, login, subject, worksheet):
868
Calculates the score for a user on a given worksheet.
869
Returns a 4-tuple of ints, consisting of:
870
(No. mandatory exercises completed,
871
Total no. mandatory exercises,
872
No. optional exercises completed,
873
Total no. optional exercises)
875
self.start_transaction()
881
# Get a list of problems and optionality for all problems in the
883
query = ("""SELECT problemid, optional FROM worksheet_problem
884
WHERE worksheetid = (SELECT worksheetid FROM worksheet
885
WHERE subject = %s and identifier = %s);"""
886
% (_escape(subject), _escape(worksheet)))
887
result = self.db.query(query)
888
# Now get the student's pass/fail for each problem in this worksheet
889
for problemid, optional in result.getresult():
890
done, _ = self.get_problem_status(login, problemid)
891
# done is a bool, whether this student has completed that
893
if _parse_boolean(optional):
895
if done: opt_done += 1
898
if done: mand_done += 1
903
return mand_done, mand_total, opt_done, opt_total
905
# ENROLMENT INFORMATION
907
def add_enrolment(self, login, subj_code, semester, year=None, dry=False):
909
Enrol a student in the given offering of a subject.
910
Returns True on success, False on failure (which usually means either
911
the student is already enrolled in the subject, the student was not
912
found, or no offering existed with the given details).
913
The return value can usually be ignored.
915
subj_code = str(subj_code)
916
semester = str(semester)
918
year = str(time.gmtime().tm_year)
922
INSERT INTO enrolment (loginid, offeringid)
924
(SELECT loginid FROM login WHERE login=%s),
926
FROM offering, subject, semester
927
WHERE subject.subjectid = offering.subject
928
AND semester.semesterid = offering.semesterid
929
AND subj_code=%s AND semester=%s AND year=%s)
930
);""" % (_escape(login), _escape(subj_code), _escape(semester),
935
result = self.db.query(query)
936
except pg.ProgrammingError:
940
# SUBJECTS AND ENROLEMENT
942
def get_subjects(self, dry=False):
944
Get all subjects in IVLE.
945
Returns a list of dicts (all values strings), with the keys:
946
subj_code, subj_name, subj_short_name, url
948
return self.get_all("subject",
949
("subjectid", "subj_code", "subj_name", "subj_short_name", "url"),
952
def get_offering_semesters(self, subjectid, dry=False):
954
Get the semester information for a subject as well as providing
955
information about if the subject is active and which semester it is in.
958
SELECT offeringid, subj_name, year, semester, active
959
FROM semester, offering, subject
960
WHERE offering.semesterid = semester.semesterid AND
961
offering.subject = subject.subjectid AND
962
offering.subject = %d;"""%subjectid
965
results = self.db.query(query).dictresult()
966
# Parse boolean varibles
967
for result in results:
968
result['active'] = _parse_boolean(result['active'])
971
def get_offering_members(self, offeringid, dry=False):
973
Gets the logins of all the people enroled in an offering
976
SELECT login.login AS login, login.fullname AS fullname
977
FROM login, enrolment
978
WHERE login.loginid = enrolment.loginid AND
979
enrolment.offeringid = %d
980
ORDER BY login.login;"""%offeringid
983
return self.db.query(query).dictresult()
986
def get_enrolment(self, login, dry=False):
988
Get all offerings (in IVLE) the student is enrolled in.
989
Returns a list of dicts (all values strings), with the keys:
990
offeringid, subj_code, subj_name, subj_short_name, year, semester, url
993
SELECT offering.offeringid, subj_code, subj_name, subj_short_name,
994
semester.year, semester.semester, subject.url
995
FROM login, enrolment, offering, subject, semester
996
WHERE enrolment.offeringid=offering.offeringid
997
AND login.loginid=enrolment.loginid
998
AND offering.subject=subject.subjectid
999
AND semester.semesterid=offering.semesterid
1000
AND enrolment.active
1001
AND login=%s;""" % _escape(login)
1004
return self.db.query(query).dictresult()
1006
def get_enrolment_groups(self, login, offeringid, dry=False):
1008
Get all groups the user is member of in the given offering.
1009
Returns a list of dicts (all values strings), with the keys:
1013
SELECT project_group.groupnm as name, project_group.nick as nick
1014
FROM project_set, project_group, group_member, login
1015
WHERE login.login=%s
1016
AND project_set.offeringid=%s
1017
AND group_member.loginid=login.loginid
1018
AND project_group.groupid=group_member.groupid
1019
AND project_group.projectsetid=project_set.projectsetid
1020
""" % (_escape(login), _escape(offeringid))
1023
return self.db.query(query).dictresult()
1025
def get_subjects_status(self, login, dry=False):
1027
Get all subjects in IVLE, split into lists of enrolled and unenrolled
1029
Returns a tuple of lists (enrolled, unenrolled) of dicts
1030
(all values strings) with the keys:
1031
subj_code, subj_name, subj_short_name, url
1033
enrolments = self.get_enrolment(login)
1034
all_subjects = self.get_subjects()
1036
enrolled_set = set(x['subj_code'] for x in enrolments)
1038
enrolled_subjects = [x for x in all_subjects
1039
if x['subj_code'] in enrolled_set]
1040
unenrolled_subjects = [x for x in all_subjects
1041
if x['subj_code'] not in enrolled_set]
1042
enrolled_subjects.sort(key=lambda x: x['subj_code'])
1043
unenrolled_subjects.sort(key=lambda x: x['subj_code'])
1044
return (enrolled_subjects, unenrolled_subjects)
1048
def get_groups_by_user(self, login, offeringid=None, dry=False):
1050
Get all project groups the student is in, corresponding to a
1051
particular subject offering (or all offerings, if omitted).
1052
Returns a list of tuples:
1053
(int groupid, str groupnm, str group_nick, bool is_member).
1054
(Note: If is_member is false, it means they have just been invited to
1055
this group, not a member).
1057
if offeringid is None:
1060
and_projectset_table = ", project_set"
1062
AND project_group.projectsetid = project_set.projectsetid
1063
AND project_set.offeringid = %s""" % _escape(offeringid)
1064
# Union both the groups this user is a member of, and the groups this
1065
# user is invited to.
1067
SELECT project_group.groupid, groupnm, project_group.nick, True
1068
FROM project_group, group_member, login %(and_projectset_table)s
1069
WHERE project_group.groupid = group_member.groupid
1070
AND group_member.loginid = login.loginid
1071
AND login = %(login)s
1074
SELECT project_group.groupid, groupnm, project_group.nick, False
1075
FROM project_group, group_invitation, login %(and_projectset_table)s
1076
WHERE project_group.groupid = group_invitation.groupid
1077
AND group_invitation.loginid = login.loginid
1078
AND login = %(login)s
1080
;""" % {"login": _escape(login), "and_offering": and_offering,
1081
"and_projectset_table": and_projectset_table}
1084
# Convert 't' -> True, 'f' -> False
1085
return [(groupid, groupnm, nick, ismember == 't')
1086
for groupid, groupnm, nick, ismember
1087
in self.db.query(query).getresult()]
1089
def get_offering_info(self, projectsetid, dry=False):
1090
"""Takes information from projectset and returns useful information
1091
about the subject and semester. Returns as a dictionary.
1094
SELECT subjectid, subj_code, subj_name, subj_short_name, url, year, semester,
1096
FROM subject, offering, semester, project_set
1097
WHERE offering.subject = subject.subjectid AND
1098
offering.semesterid = semester.semesterid AND
1099
project_set.offeringid = offering.offeringid AND
1100
project_set.projectsetid = %d;"""%projectsetid
1103
return self.db.query(query).dictresult()[0]
1105
def get_projectgroup_members(self, groupid, dry=False):
1106
"""Returns the logins of all students in a project group
1109
SELECT login.login as login, login.fullname as fullname
1110
FROM login, group_member
1111
WHERE login.loginid = group_member.loginid AND
1112
group_member.groupid = %d
1113
ORDER BY login.login;"""%groupid
1116
return self.db.query(query).dictresult()
1118
def get_projectsets_by_offering(self, offeringid, dry=False):
1119
"""Returns all the projectsets in a particular offering"""
1121
SELECT projectsetid, max_students_per_group
1123
WHERE project_set.offeringid = %d;"""%offeringid
1126
return self.db.query(query).dictresult()
1128
def get_groups_by_projectset(self, projectsetid, dry=False):
1129
"""Returns all the groups that are in a particular projectset"""
1131
SELECT groupid, groupnm, nick, createdby, epoch
1133
WHERE project_group.projectsetid = %d;"""%projectsetid
1136
return self.db.query(query).dictresult()
1139
"""Close the DB connection. Do not call any other functions after
1140
this. (The behaviour of doing so is undefined).
added
removed
ivle/db.py
