1 | # $Id$ |
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2 | # |
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3 | # |
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4 | |
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5 | """This module defines a class to access to a SQLite database backend.""" |
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6 | |
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7 | import time |
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8 | |
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9 | from pykota.storage import PyKotaStorageError, BaseStorage |
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10 | from pykota.storages.sql import SQLStorage |
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11 | |
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12 | try : |
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13 | from pysqlite2 import dbapi2 as sqlite |
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14 | except ImportError : |
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15 | import sys |
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16 | # TODO : to translate or not to translate ? |
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17 | raise PyKotaStorageError, "This python version (%s) doesn't seem to have the PySQLite module installed correctly." % sys.version.split()[0] |
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18 | |
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19 | class Storage(BaseStorage, SQLStorage) : |
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20 | def __init__(self, pykotatool, host, dbname, user, passwd) : |
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21 | """Opens the SQLite database connection.""" |
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22 | BaseStorage.__init__(self, pykotatool) |
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23 | |
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24 | self.tool.logdebug("Trying to open database (dbname=%s)..." % dbname) |
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25 | self.database = sqlite.connect(dbname, isolation_level=None) |
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26 | self.cursor = self.database.cursor() |
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27 | self.closed = 0 |
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28 | self.tool.logdebug("Database opened (dbname=%s)" % dbname) |
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29 | |
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30 | def close(self) : |
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31 | """Closes the database connection.""" |
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32 | if not self.closed : |
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33 | self.cursor.close() |
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34 | self.database.close() |
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35 | self.closed = 1 |
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36 | self.tool.logdebug("Database closed.") |
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37 | |
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38 | def beginTransaction(self) : |
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39 | """Starts a transaction.""" |
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40 | self.before = time.time() |
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41 | self.cursor.execute("BEGIN;") |
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42 | self.tool.logdebug("Transaction begins...") |
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43 | |
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44 | def commitTransaction(self) : |
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45 | """Commits a transaction.""" |
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46 | self.cursor.execute("COMMIT;") |
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47 | after = time.time() |
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48 | self.tool.logdebug("Transaction committed.") |
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49 | #self.tool.logdebug("Transaction duration : %.4f seconds" % (after - self.before)) |
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50 | |
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51 | def rollbackTransaction(self) : |
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52 | """Rollbacks a transaction.""" |
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53 | self.cursor.execute("ROLLBACK;") |
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54 | after = time.time() |
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55 | self.tool.logdebug("Transaction aborted.") |
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56 | #self.tool.logdebug("Transaction duration : %.4f seconds" % (after - self.before)) |
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57 | |
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58 | def doRawSearch(self, query) : |
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59 | """Does a raw search query.""" |
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60 | query = query.strip() |
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61 | if not query.endswith(';') : |
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62 | query += ';' |
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63 | try : |
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64 | before = time.time() |
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65 | self.tool.logdebug("QUERY : %s" % query) |
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66 | self.cursor.execute(query) |
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67 | except self.database.Error, msg : |
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68 | raise PyKotaStorageError, str(msg) |
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69 | else : |
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70 | result = self.cursor.fetchall() |
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71 | after = time.time() |
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72 | #self.tool.logdebug("Query Duration : %.4f seconds" % (after - before)) |
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73 | return result |
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74 | |
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75 | def doSearch(self, query) : |
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76 | """Does a search query.""" |
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77 | result = self.doRawSearch(query) |
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78 | if result : |
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79 | rows = [] |
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80 | fields = {} |
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81 | for i in range(len(self.cursor.description)) : |
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82 | fields[i] = self.cursor.description[i][0] |
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83 | for row in result : |
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84 | rowdict = {} |
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85 | for field in fields.keys() : |
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86 | value = row[field] |
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87 | try : |
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88 | value = value.encode("UTF-8") |
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89 | except : |
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90 | pass |
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91 | rowdict[fields[field]] = value |
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92 | rows.append(rowdict) |
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93 | return rows |
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94 | |
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95 | def doModify(self, query) : |
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96 | """Does a (possibly multiple) modify query.""" |
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97 | query = query.strip() |
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98 | if not query.endswith(';') : |
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99 | query += ';' |
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100 | try : |
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101 | before = time.time() |
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102 | self.tool.logdebug("QUERY : %s" % query) |
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103 | self.cursor.execute(query) |
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104 | except self.database.Error, msg : |
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105 | self.tool.logdebug("Query failed : %s" % repr(msg)) |
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106 | raise PyKotaStorageError, str(msg) |
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107 | else : |
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108 | after = time.time() |
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109 | #self.tool.logdebug("Query Duration : %.4f seconds" % (after - before)) |
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110 | |
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111 | def doQuote(self, field) : |
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112 | """Quotes a field for use as a string in SQL queries.""" |
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113 | if type(field) == type(0.0) : |
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114 | return field |
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115 | elif type(field) == type(0) : |
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116 | return field |
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117 | elif type(field) == type(0L) : |
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118 | return field |
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119 | elif field is not None : |
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120 | return ("'%s'" % field.replace("'", "''")).decode("UTF-8") |
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121 | else : |
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122 | return "NULL" |
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123 | |
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124 | def prepareRawResult(self, result) : |
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125 | """Prepares a raw result by including the headers.""" |
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126 | if result : |
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127 | entries = [tuple([f[0] for f in self.cursor.description])] |
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128 | for entry in result : |
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129 | row = [] |
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130 | for value in entry : |
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131 | try : |
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132 | value = value.encode("UTF-8") |
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133 | except : |
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134 | pass |
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135 | row.append(value) |
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136 | entries.append(tuple(row)) |
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137 | return entries |
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138 | |
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