Remove third_party/twisted_8_1

third_party/twisted_8_1/twisted/enterprise/sqlreflector.py

-# -*- test-case-name: twisted.test.test_reflector -*-
-# Copyright (c) 2001-2004 Twisted Matrix Laboratories.
-# See LICENSE for details.
-
-
-from twisted.enterprise import reflector
-from twisted.enterprise.util import DBError, getKeyColumn, quote, safe
-from twisted.enterprise.util import _TableInfo
-from twisted.enterprise.row import RowObject
-
-from twisted.python import reflect
-
-class SQLReflector(reflector.Reflector):
-    """
-    DEPRECATED.
-    
-    I reflect on a database and load RowObjects from it.
-
-    In order to do this, I interrogate a relational database to
-    extract schema information and interface with RowObject class
-    objects that can interact with specific tables. 
-    """
-    populated = 0
-    conditionalLabels = {
-        reflector.EQUAL       : "=",
-        reflector.LESSTHAN    : "<",
-        reflector.GREATERTHAN : ">",
-        reflector.LIKE        : "like"
-        }
-
-    def __init__(self, dbpool, rowClasses):
-        """Initialize me against a database.
-        """
-        reflector.Reflector.__init__(self, rowClasses)
-        self.dbpool = dbpool
-
-    def _populate(self):
-        self._transPopulateSchema()
-
-    def _transPopulateSchema(self):
-        """Used to construct the row classes in a single interaction.
-        """
-        for rc in self.rowClasses:
-            if not issubclass(rc, RowObject):
-                raise DBError("Stub class (%s) is not derived from RowObject" % reflect.qual(rc.rowClass))
-
-            self._populateSchemaFor(rc)
-        self.populated = 1
-
-    def _populateSchemaFor(self, rc):
-        """Construct all the SQL templates for database operations on
-        <tableName> and populate the class <rowClass> with that info.
-        """
-        attributes = ("rowColumns", "rowKeyColumns", "rowTableName" )
-        for att in attributes:
-            if not hasattr(rc, att):
-                raise DBError("RowClass %s must have class variable: %s" % (rc, att))
-
-        tableInfo = _TableInfo(rc)
-        tableInfo.updateSQL = self.buildUpdateSQL(tableInfo)
-        tableInfo.insertSQL = self.buildInsertSQL(tableInfo)
-        tableInfo.deleteSQL = self.buildDeleteSQL(tableInfo)
-        self.populateSchemaFor(tableInfo)
-
-    def escape_string(self, text):
-        """Escape a string for use in an SQL statement. The default
-        implementation escapes ' with '' and \ with \\. Redefine this
-        function in a subclass if your database server uses different
-        escaping rules.
-        """
-        return safe(text)
-
-    def quote_value(self, value, type):
-        """Format a value for use in an SQL statement.
-
-        @param value: a value to format as data in SQL.
-        @param type: a key in util.dbTypeMap.
-        """
-        return quote(value, type, string_escaper=self.escape_string)
-
-    def loadObjectsFrom(self, tableName, parentRow=None, data=None,
-                        whereClause=None, forceChildren=0):
-        """Load a set of RowObjects from a database.
-
-        Create a set of python objects of <rowClass> from the contents
-        of a table populated with appropriate data members.
-        Example::
-
-          |  class EmployeeRow(row.RowObject):
-          |      pass
-          |
-          |  def gotEmployees(employees):
-          |      for emp in employees:
-          |          emp.manager = "fred smith"
-          |          manager.updateRow(emp)
-          |
-          |  reflector.loadObjectsFrom("employee",
-          |                          data = userData,
-          |                          whereClause = [("manager" , EQUAL, "fred smith")]
-          |                          ).addCallback(gotEmployees)
-
-        NOTE: the objects and all children should be loaded in a single transaction.
-        NOTE: can specify a parentRow _OR_ a whereClause.
-
-        """
-        if parentRow and whereClause:
-            raise DBError("Must specify one of parentRow _OR_ whereClause")
-        if parentRow:
-            info = self.getTableInfo(parentRow)
-            relationship = info.getRelationshipFor(tableName)
-            whereClause = self.buildWhereClause(relationship, parentRow)
-        elif whereClause:
-            pass
-        else:
-            whereClause = []
-        return self.dbpool.runInteraction(self._rowLoader, tableName,
-                                          parentRow, data, whereClause,
-                                          forceChildren)
-
-    def _rowLoader(self, transaction, tableName, parentRow, data,
-                   whereClause, forceChildren):
-        """immediate loading of rowobjects from the table with the whereClause.
-        """
-        tableInfo = self.schema[tableName]
-        # Build the SQL for the query
-        sql = "SELECT "
-        first = 1
-        for column, type in tableInfo.rowColumns:
-            if first:
-                first = 0
-            else:
-                sql = sql + ","
-            sql = sql + " %s" % column
-        sql = sql + " FROM %s " % (tableName)
-        if whereClause:
-            sql += " WHERE "
-            first = 1
-            for wItem in whereClause:
-                if first:
-                    first = 0
-                else:
-                    sql += " AND "
-                (columnName, cond, value) = wItem
-                t = self.findTypeFor(tableName, columnName)
-                quotedValue = self.quote_value(value, t)
-                sql += "%s %s %s" % (columnName, self.conditionalLabels[cond],
-                                     quotedValue)
-
-        # execute the query
-        transaction.execute(sql)
-        rows = transaction.fetchall()
-
-        # construct the row objects
-        results = []
-        newRows = []
-        for args in rows:
-            kw = {}
-            for i in range(0,len(args)):
-                ColumnName = tableInfo.rowColumns[i][0].lower()
-                for attr, type in tableInfo.rowClass.rowColumns:
-                    if attr.lower() == ColumnName:
-                        kw[attr] = args[i]
-                        break
-            # find the row in the cache or add it
-            resultObject = self.findInCache(tableInfo.rowClass, kw)
-            if not resultObject:
-                meth = tableInfo.rowFactoryMethod[0]
-                resultObject = meth(tableInfo.rowClass, data, kw)
-                self.addToCache(resultObject)
-                newRows.append(resultObject)
-            results.append(resultObject)
-
-        # add these rows to the parentRow if required
-        if parentRow:
-            self.addToParent(parentRow, newRows, tableName)
-
-        # load children or each of these rows if required
-        for relationship in tableInfo.relationships:
-            if not forceChildren and not relationship.autoLoad:
-                continue
-            for row in results:
-                # build where clause
-                childWhereClause = self.buildWhereClause(relationship, row)
-                # load the children immediately, but do nothing with them
-                self._rowLoader(transaction,
-                                relationship.childRowClass.rowTableName,
-                                row, data, childWhereClause, forceChildren)
-
-        return results
-
-    def findTypeFor(self, tableName, columnName):
-        tableInfo = self.schema[tableName]
-        columnName = columnName.lower()
-        for column, type in tableInfo.rowColumns:
-            if column.lower() == columnName:
-                return type
-
-    def buildUpdateSQL(self, tableInfo):
-        """(Internal) Build SQL template to update a RowObject.
-
-        Returns: SQL that is used to contruct a rowObject class.
-        """
-        sql = "UPDATE %s SET" % tableInfo.rowTableName
-        # build update attributes
-        first = 1
-        for column, type in tableInfo.rowColumns:
-            if getKeyColumn(tableInfo.rowClass, column):
-                continue
-            if not first:
-                sql = sql + ", "
-            sql = sql + " %s = %s" % (column, "%s")
-            first = 0
-
-        # build where clause
-        first = 1
-        sql = sql + " WHERE "
-        for keyColumn, type in tableInfo.rowKeyColumns:
-            if not first:
-                sql = sql + " AND "
-            sql = sql + " %s = %s " % (keyColumn, "%s")
-            first = 0
-        return sql
-
-    def buildInsertSQL(self, tableInfo):
-        """(Internal) Build SQL template to insert a new row.
-
-        Returns: SQL that is used to insert a new row for a rowObject
-        instance not created from the database.
-        """
-        sql = "INSERT INTO %s (" % tableInfo.rowTableName
-        # build column list
-        first = 1
-        for column, type in tableInfo.rowColumns:
-            if not first:
-                sql = sql + ", "
-            sql = sql + column
-            first = 0
-
-        sql = sql + " ) VALUES ("
-
-        # build values list
-        first = 1
-        for column, type in tableInfo.rowColumns:
-            if not first:
-                sql = sql + ", "
-            sql = sql + "%s"
-            first = 0
-
-        sql = sql + ")"
-        return sql
-
-    def buildDeleteSQL(self, tableInfo):
-        """Build the SQL template to delete a row from the table.
-        """
-        sql = "DELETE FROM %s " % tableInfo.rowTableName
-        # build where clause
-        first = 1
-        sql = sql + " WHERE "
-        for keyColumn, type in tableInfo.rowKeyColumns:
-            if not first:
-                sql = sql + " AND "
-            sql = sql + " %s = %s " % (keyColumn, "%s")
-            first = 0
-        return sql
-
-    def updateRowSQL(self, rowObject):
-        """Build SQL to update the contents of rowObject.
-        """
-        args = []
-        tableInfo = self.schema[rowObject.rowTableName]
-        # build update attributes
-        for column, type in tableInfo.rowColumns:
-            if not getKeyColumn(rowObject.__class__, column):
-                args.append(self.quote_value(rowObject.findAttribute(column),
-                                             type))
-        # build where clause
-        for keyColumn, type in tableInfo.rowKeyColumns:
-            args.append(self.quote_value(rowObject.findAttribute(keyColumn),
-                                         type))
-
-        return self.getTableInfo(rowObject).updateSQL % tuple(args)
-
-    def updateRow(self, rowObject):
-        """Update the contents of rowObject to the database.
-        """
-        sql = self.updateRowSQL(rowObject)
-        rowObject.setDirty(0)
-        return self.dbpool.runOperation(sql)
-
-    def insertRowSQL(self, rowObject):
-        """Build SQL to insert the contents of rowObject.
-        """
-        args = []
-        tableInfo = self.schema[rowObject.rowTableName]        
-        # build values
-        for column, type in tableInfo.rowColumns:
-            args.append(self.quote_value(rowObject.findAttribute(column),type))
-        return self.getTableInfo(rowObject).insertSQL % tuple(args)
-
-    def insertRow(self, rowObject):
-        """Insert a new row for rowObject.
-        """
-        rowObject.setDirty(0)
-        sql = self.insertRowSQL(rowObject)
-        return self.dbpool.runOperation(sql)
-
-    def deleteRowSQL(self, rowObject):
-        """Build SQL to delete rowObject from the database.
-        """
-        args = []
-        tableInfo = self.schema[rowObject.rowTableName]        
-        # build where clause
-        for keyColumn, type in tableInfo.rowKeyColumns:
-            args.append(self.quote_value(rowObject.findAttribute(keyColumn),
-                                         type))
-
-        return self.getTableInfo(rowObject).deleteSQL % tuple(args)
-
-    def deleteRow(self, rowObject):
-        """Delete the row for rowObject from the database.
-        """
-        sql = self.deleteRowSQL(rowObject)
-        self.removeFromCache(rowObject)
-        return self.dbpool.runOperation(sql)
-
-
-__all__ = ['SQLReflector']