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| 1 | +# -*- coding: utf-8 -*- |
| 2 | +from tarantool.connection import Connection as BaseConnection |
| 3 | +from tarantool.error import * |
| 4 | + |
| 5 | + |
| 6 | +paramstyle = 'named' |
| 7 | +apilevel = "2.0" |
| 8 | +threadsafety = 1 |
| 9 | + |
| 10 | + |
| 11 | +class Cursor: |
| 12 | + |
| 13 | + def __init__(self, conn): |
| 14 | + self._c = conn |
| 15 | + self._lastrowid = None |
| 16 | + self._rowcount = None |
| 17 | + self.arraysize = 1 |
| 18 | + self._rows = None |
| 19 | + |
| 20 | + def callproc(self, procname, *params): |
| 21 | + """ |
| 22 | + Call a stored database procedure with the given name. The sequence of |
| 23 | + parameters must contain one entry for each argument that the |
| 24 | + procedure expects. The result of the call is returned as modified |
| 25 | + copy of the input sequence. Input parameters are left untouched, |
| 26 | + output and input/output parameters replaced with possibly new values. |
| 27 | + """ |
| 28 | + raise NotSupportedError("callproc() method is not supported") |
| 29 | + |
| 30 | + @property |
| 31 | + def rows(self): |
| 32 | + return self._rows |
| 33 | + |
| 34 | + @property |
| 35 | + def description(self): |
| 36 | + # FIXME Implement this method please |
| 37 | + raise NotImplementedError("description() property is not implemented") |
| 38 | + |
| 39 | + def close(self): |
| 40 | + """ |
| 41 | + Close the cursor now (rather than whenever __del__ is called). |
| 42 | + The cursor will be unusable from this point forward; DatabaseError |
| 43 | + exception will be raised if any operation is attempted with |
| 44 | + the cursor. |
| 45 | + """ |
| 46 | + self._c = None |
| 47 | + self._rows = None |
| 48 | + self._lastrowid = None |
| 49 | + self._rowcount = None |
| 50 | + |
| 51 | + def _check_not_closed(self, error=None): |
| 52 | + if self._c is None: |
| 53 | + raise InterfaceError(error or "Can not operate on a closed cursor") |
| 54 | + if self._c.is_closed(): |
| 55 | + raise InterfaceError("The cursor can not be used " |
| 56 | + "with a closed connection") |
| 57 | + |
| 58 | + def execute(self, query, params=None): |
| 59 | + """ |
| 60 | + Prepare and execute a database operation (query or command). |
| 61 | + """ |
| 62 | + self._check_not_closed("Can not execute on closed cursor.") |
| 63 | + |
| 64 | + response = self._c.execute(query, params) |
| 65 | + |
| 66 | + self._rows = response.data |
| 67 | + self._rowcount = response.affected_row_count or -1 |
| 68 | + if response.autoincrement_ids: |
| 69 | + self._lastrowid = response.autoincrement_ids[-1] |
| 70 | + else: |
| 71 | + self._lastrowid = None |
| 72 | + |
| 73 | + def executemany(self, query, param_sets): |
| 74 | + self._check_not_closed("Can not execute on closed cursor.") |
| 75 | + rowcount = 0 |
| 76 | + for params in param_sets: |
| 77 | + self.execute(query, params) |
| 78 | + if self.rowcount == -1: |
| 79 | + rowcount = -1 |
| 80 | + if rowcount != -1: |
| 81 | + rowcount += self.rowcount |
| 82 | + self._rowcount = rowcount |
| 83 | + |
| 84 | + @property |
| 85 | + def lastrowid(self): |
| 86 | + """ |
| 87 | + This read-only attribute provides the rowid of the last modified row |
| 88 | + (most databases return a rowid only when a single INSERT operation is |
| 89 | + performed). |
| 90 | + """ |
| 91 | + return self._lastrowid |
| 92 | + |
| 93 | + @property |
| 94 | + def rowcount(self): |
| 95 | + """ |
| 96 | + This read-only attribute specifies the number of rows that the last |
| 97 | + .execute*() produced (for DQL statements like SELECT) or affected ( |
| 98 | + for DML statements like UPDATE or INSERT). |
| 99 | + """ |
| 100 | + return self._rowcount |
| 101 | + |
| 102 | + def _check_result_set(self, error=None): |
| 103 | + """ |
| 104 | + Non-public method for raising an error when Cursor object does not have |
| 105 | + any row to fetch. Useful for checking access after DQL requests. |
| 106 | + """ |
| 107 | + if self._rows is None: |
| 108 | + raise InterfaceError(error or "No result set to fetch from") |
| 109 | + |
| 110 | + def fetchone(self): |
| 111 | + """ |
| 112 | + Fetch the next row of a query result set, returning a single |
| 113 | + sequence, or None when no more data is available. |
| 114 | + """ |
| 115 | + self._check_result_set() |
| 116 | + return self.fetchmany(1)[0] if self._rows else None |
| 117 | + |
| 118 | + def fetchmany(self, size=None): |
| 119 | + """ |
| 120 | + Fetch the next set of rows of a query result, returning a sequence of |
| 121 | + sequences (e.g. a list of tuples). An empty sequence is returned when |
| 122 | + no more rows are available. |
| 123 | + """ |
| 124 | + self._check_result_set() |
| 125 | + |
| 126 | + size = size or self.arraysize |
| 127 | + |
| 128 | + if len(self._rows) < size: |
| 129 | + items = self._rows |
| 130 | + self._rows = [] |
| 131 | + else: |
| 132 | + items, self._rows = self._rows[:size], self._rows[size:] |
| 133 | + |
| 134 | + return items |
| 135 | + |
| 136 | + def fetchall(self): |
| 137 | + """Fetch all (remaining) rows of a query result, returning them as a |
| 138 | + sequence of sequences (e.g. a list of tuples). Note that the cursor's |
| 139 | + arraysize attribute can affect the performance of this operation. |
| 140 | + """ |
| 141 | + self._check_result_set() |
| 142 | + |
| 143 | + items = self._rows |
| 144 | + self._rows = [] |
| 145 | + return items |
| 146 | + |
| 147 | + def setinputsizes(self, sizes): |
| 148 | + """PEP-249 allows to not implement this method and do nothing.""" |
| 149 | + |
| 150 | + def setoutputsize(self, size, column=None): |
| 151 | + """PEP-249 allows to not implement this method and do nothing.""" |
| 152 | + |
| 153 | + |
| 154 | +class Connection(BaseConnection): |
| 155 | + |
| 156 | + def __init__(self, *args, **kwargs): |
| 157 | + super(Connection, self).__init__(*args, **kwargs) |
| 158 | + self._set_autocommit(kwargs.get('autocommit', True)) |
| 159 | + |
| 160 | + def _set_autocommit(self, autocommit): |
| 161 | + """Autocommit is True by default and the default will be changed |
| 162 | + to False. Set the autocommit property explicitly to True or verify |
| 163 | + it when lean on autocommit behaviour.""" |
| 164 | + if not isinstance(autocommit, bool): |
| 165 | + raise InterfaceError("autocommit parameter must be boolean, " |
| 166 | + "not %s" % autocommit.__class__.__name__) |
| 167 | + if autocommit is False: |
| 168 | + raise NotSupportedError("The connector supports " |
| 169 | + "only autocommit mode") |
| 170 | + self._autocommit = autocommit |
| 171 | + |
| 172 | + @property |
| 173 | + def autocommit(self): |
| 174 | + """Autocommit state""" |
| 175 | + return self._autocommit |
| 176 | + |
| 177 | + @autocommit.setter |
| 178 | + def autocommit(self, autocommit): |
| 179 | + """Set autocommit state""" |
| 180 | + self._set_autocommit(autocommit) |
| 181 | + |
| 182 | + def _check_not_closed(self, error=None): |
| 183 | + """ |
| 184 | + Checks if the connection is not closed and rises an error if it is. |
| 185 | + """ |
| 186 | + if self.is_closed(): |
| 187 | + raise InterfaceError(error or "The connector is closed") |
| 188 | + |
| 189 | + def close(self): |
| 190 | + """ |
| 191 | + Closes the connection |
| 192 | + """ |
| 193 | + self._check_not_closed("The closed connector can not be closed again.") |
| 194 | + super(Connection, self).close() |
| 195 | + |
| 196 | + def commit(self): |
| 197 | + """ |
| 198 | + Commit any pending transaction to the database. |
| 199 | + """ |
| 200 | + self._check_not_closed("Can not commit on the closed connection") |
| 201 | + |
| 202 | + def rollback(self): |
| 203 | + """ |
| 204 | + Roll back pending transaction |
| 205 | + """ |
| 206 | + self._check_not_closed("Can not roll back on a closed connection") |
| 207 | + raise NotSupportedError("Transactions are not supported in this" |
| 208 | + "version of connector") |
| 209 | + |
| 210 | + def cursor(self): |
| 211 | + """ |
| 212 | + Return a new Cursor Object using the connection. |
| 213 | + """ |
| 214 | + self._check_not_closed("Cursor creation is not allowed on a closed " |
| 215 | + "connection") |
| 216 | + return Cursor(self) |
| 217 | + |
| 218 | + |
| 219 | +def connect(dsn=None, host=None, port=None, |
| 220 | + user=None, password=None, **kwargs): |
| 221 | + """ |
| 222 | + Constructor for creating a connection to the database. |
| 223 | +
|
| 224 | + :param str dsn: Data source name (Tarantool URI) |
| 225 | + ([[[username[:password]@]host:]port) |
| 226 | + :param str host: Server hostname or IP-address |
| 227 | + :param int port: Server port |
| 228 | + :param str user: Tarantool user |
| 229 | + :param str password: User password |
| 230 | + :rtype: Connection |
| 231 | + """ |
| 232 | + |
| 233 | + if dsn: |
| 234 | + raise NotImplementedError("dsn param is not implemented in" |
| 235 | + "this version of dbapi module") |
| 236 | + params = {} |
| 237 | + if host: |
| 238 | + params["host"] = host |
| 239 | + if port: |
| 240 | + params["port"] = port |
| 241 | + if user: |
| 242 | + params["user"] = user |
| 243 | + if password: |
| 244 | + params["password"] = password |
| 245 | + |
| 246 | + kwargs.update(params) |
| 247 | + |
| 248 | + return Connection(**kwargs) |
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