odb.py

在 linux平台上的网页编程的模板

        row = self.__defaultRowClass(self,None,create=1,replace=replace)
        for (cname, ctype, opts) in self.__column_list:
            if opts['default'] is not None and ctype is not kIncInteger:
                row[cname] = opts['default']
        return row

class Row:
    __instance_data_locked  = 0
    def subclassinit(self):
        pass
    def __init__(self,_table,data_dict,create=0,joined_cols = None,replace=0):

        self._inside_getattr = 0  # stop recursive __getattr__
        self._table = _table
        self._should_insert = create or replace
        self._should_replace = replace
        self._rowInactive = None
        self._joinedRows = []
        
        self.__pk_match_spec = None
        self.__vcoldata = {}
        self.__inc_coldata = {}

        self.__joined_cols_dict = {}
        for a_col in joined_cols or []:
            self.__joined_cols_dict[a_col] = 1
        
        if create:
            self.__coldata = {}
        else:
            if type(data_dict) != type({}):
                raise eInternalError, "rowdict instantiate with bad data_dict"
            self.__coldata = data_dict
            self.__unpackVColumn()

        self.markClean()

        self.subclassinit()
        self.__instance_data_locked = 1

    def joinRowData(self,another_row):
        self._joinedRows.append(another_row)

    def getPKMatchSpec(self):
        return self.__pk_match_spec

    def markClean(self):
        self.__vcolchanged = 0
        self.__colchanged_dict = {}

        for key in self.__inc_coldata.keys():
            self.__coldata[key] = self.__coldata.get(key, 0) + self.__inc_coldata[key]

        self.__inc_coldata = {}

        if not self._should_insert:
            # rebuild primary column match spec
            new_match_spec = []
            for col_name in self._table.getPrimaryKeyList():
                try:
                    rdata = self[col_name]
                except KeyError:
                    raise eInternalError, "must have primary key data filled in to save %s:Row(col:%s)" % (self._table.getTableName(),col_name)
                    
                new_match_spec.append( (col_name, rdata) )
            self.__pk_match_spec = new_match_spec

    def __unpackVColumn(self):
        if self._table.hasValueColumn():
            pass
        
    def __packVColumn(self):
        if self._table.hasValueColumn():
            pass

    ## ----- utility stuff ----------------------------------

    def __del__(self):
        # check for unsaved changes
        changed_list = self.changedList()
        if len(changed_list):
            info = "unsaved Row for table (%s) lost, call discard() to avoid this error. Lost changes: %s\n" % (self._table.getTableName(), repr(changed_list)[:256])
            if 0:
                raise eUnsavedObjectLost, info
            else:
                sys.stderr.write(info)
                

    def __repr__(self):
        return "Row from (%s): %s" % (self._table.getTableName(),repr(self.__coldata) + repr(self.__vcoldata))

    ## ---- class emulation --------------------------------

    def __getattr__(self,key):
        if self._inside_getattr:
          raise AttributeError, "recursively called __getattr__ (%s,%s)" % (key,self._table.getTableName())
        try:
            self._inside_getattr = 1
            try:
                return self[key]
            except KeyError:
                if self._table.hasColumn(key) or self._table.hasVColumn(key):
                    return None
                else:
                    raise AttributeError, "unknown field '%s' in Row(%s)" % (key,self._table.getTableName())
        finally:
            self._inside_getattr = 0

    def __setattr__(self,key,val):
        if not self.__instance_data_locked:
            self.__dict__[key] = val
        else:
            my_dict = self.__dict__
            if my_dict.has_key(key):
                my_dict[key] = val
            else:
                # try and put it into the rowdata
                try:
                    self[key] = val
                except KeyError, reason:
                    raise AttributeError, reason


    ## ---- dict emulation ---------------------------------
    
    def __getitem__(self,key):
        self.checkRowActive()

        try:
            c_type = self._table.columnType(key)
        except eNoSuchColumn, reason:
            # Ugh, this sucks, we can't determine the type for a joined
            # row, so we just default to kVarString and let the code below
            # determine if this is a joined column or not
            c_type = kVarString

        if c_type == kIncInteger:
            c_data = self.__coldata.get(key, 0) 
            if c_data is None: c_data = 0
            i_data = self.__inc_coldata.get(key, 0)
            if i_data is None: i_data = 0
            return c_data + i_data
        
        try:
            return self.__coldata[key]
        except KeyError:
            try:
                return self.__vcoldata[key]
            except KeyError:
                for a_joined_row in self._joinedRows:
                    try:
                        return a_joined_row[key]
                    except KeyError:
                        pass

                raise KeyError, "unknown column %s in %s" % (key,self)

    def __setitem__(self,key,data):
        self.checkRowActive()
        
        try:
            newdata = self._table.convertDataForColumn(data,key)
        except eNoSuchColumn, reason:
            raise KeyError, reason

        if self._table.hasColumn(key):
            self.__coldata[key] = newdata
            self.__colchanged_dict[key] = 1
        elif self._table.hasVColumn(key):
            self.__vcoldata[key] = newdata
            self.__vcolchanged = 1
        else:
            for a_joined_row in self._joinedRows:
                try:
                    a_joined_row[key] = data
                    return
                except KeyError:
                    pass
            raise KeyError, "unknown column name %s" % key

    def __delitem__(self,key,data):
        self.checkRowActive()
        
        if self.table.hasVColumn(key):
            del self.__vcoldata[key]
        else:
            for a_joined_row in self._joinedRows:
                try:
                    del a_joined_row[key]
                    return
                except KeyError:
                    pass
            raise KeyError, "unknown column name %s" % key


    def copyFrom(self,source):
        for name,t,options in self._table.getColumnList():
            if not options.has_key("autoincrement"):
                self[name] = source[name]


    # make sure that .keys(), and .items() come out in a nice order!

    def keys(self):
        self.checkRowActive()
        
        key_list = []
        for name,t,options in self._table.getColumnList():
            key_list.append(name)
        for name in self.__joined_cols_dict.keys():
            key_list.append(name)

        for a_joined_row in self._joinedRows:
            key_list = key_list + a_joined_row.keys()
            
        return key_list


    def items(self):
        self.checkRowActive()
        
        item_list = []
        for name,t,options in self._table.getColumnList():
            item_list.append( (name,self[name]) )
        for name in self.__joined_cols_dict.keys():
            item_list.append( (name,self[name]) )

        for a_joined_row in self._joinedRows:
            item_list = item_list + a_joined_row.items()


        return item_list

    def values(elf):
        self.checkRowActive()

        value_list = self.__coldata.values() + self.__vcoldata.values()

        for a_joined_row in self._joinedRows:
            value_list = value_list + a_joined_row.values()

        return value_list
        

    def __len__(self):
        self.checkRowActive()
        
        my_len = len(self.__coldata) + len(self.__vcoldata)

        for a_joined_row in self._joinedRows:
            my_len = my_len + len(a_joined_row)

        return my_len

    def has_key(self,key):
        self.checkRowActive()
        
        if self.__coldata.has_key(key) or self.__vcoldata.has_key(key):
            return 1
        else:

            for a_joined_row in self._joinedRows:
                if a_joined_row.has_key(key):
                    return 1
            return 0
        
    def get(self,key,default = None):
        self.checkRowActive()

        
        
        if self.__coldata.has_key(key):
            return self.__coldata[key]
        elif self.__vcoldata.has_key(key):
            return self.__vcoldata[key]
        else:
            for a_joined_row in self._joinedRows:
                try:
                    return a_joined_row.get(key,default)
                except eNoSuchColumn:
                    pass

            if self._table.hasColumn(key):
                return default
            
            raise eNoSuchColumn, "no such column %s" % key

    def inc(self,key,count=1):
        self.checkRowActive()

        if self._table.hasColumn(key):
            try:
                self.__inc_coldata[key] = self.__inc_coldata[key] + count
            except KeyError:
                self.__inc_coldata[key] = count

            self.__colchanged_dict[key] = 1
        else:
            raise AttributeError, "unknown field '%s' in Row(%s)" % (key,self._table.getTableName())
    

    ## ----------------------------------
    ## real interface


    def fillDefaults(self):
        for field_def in self._table.fieldList():
            name,type,size,options = field_def
            if options.has_key("default"):
                self[name] = options["default"]

    ###############
    # changedList()
    #
    # returns a list of tuples for the columns which have changed
    #
    #   changedList() -> [ ('name', 'fred'), ('age', 20) ]

    def changedList(self):
        if self.__vcolchanged:
            self.__packVColumn()

        changed_list = []
        for a_col in self.__colchanged_dict.keys():
            changed_list.append( (a_col,self.get(a_col,None),self.__inc_coldata.get(a_col,None)) )

        return changed_list

    def discard(self):
        self.__coldata = None
        self.__vcoldata = None
        self.__colchanged_dict = {}
        self.__vcolchanged = 0

    def delete(self,cursor = None):
        self.checkRowActive()

        
        fromTable = self._table
        curs = cursor
        fromTable.r_deleteRow(self,cursor=curs)
        self._rowInactive = "deleted"

    def save(self,cursor = None):
        toTable = self._table

        self.checkRowActive()

        if self._should_insert:
            toTable.r_insertRow(self,replace=self._should_replace)
            self._should_insert = 0
            self._should_replace = 0
            self.markClean()  # rebuild the primary key list
        else:
            curs = cursor
            toTable.r_updateRow(self,cursor = curs)

        # the table will mark us clean!
        # self.markClean()

    def checkRowActive(self):
        if self._rowInactive:
            raise eInvalidData, "row is inactive: %s" % self._rowInactive

    def databaseSizeForColumn(self,key):
        return self._table.databaseSizeForData_ColumnName_(self[key],key)


if __name__ == "__main__":
    print "run odb_test.py"