X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=PLC%2FTable.py;h=8f434bf364c8ade9aa43025ebf1540cfa96afafe;hb=9aecb8c6fde06136bef94e2fd6fce832dc3c0c10;hp=1300cf146240eec3136a7de66f18c847230696ed;hpb=3f3ab6377438b4f81acf2c3f959dd046d410b45e;p=plcapi.git

diff --git a/PLC/Table.py b/PLC/Table.py
index 1300cf1..8f434bf 100644
--- a/PLC/Table.py
+++ b/PLC/Table.py
@@ -1,6 +1,12 @@
+from types import StringTypes, IntType, LongType
+import time
+import calendar
+
+from PLC.Timestamp import Timestamp
 from PLC.Faults import *
 from PLC.Parameter import Parameter
 
+
 class Row(dict):
     """
     Representation of a row in a database table. To use, optionally
@@ -9,17 +15,40 @@ class Row(dict):
     """
 
     # Set this to the name of the table that stores the row.
+    # e.g. table_name = "nodes"
     table_name = None
 
     # Set this to the name of the primary key of the table. It is
     # assumed that the this key is a sequence if it is not set when
     # sync() is called.
+    # e.g. primary_key="node_id"
     primary_key = None
 
-    # Set this to a dict of the valid fields of this object. Not all
-    # fields (e.g., joined fields) may be updated via sync().
+    # Set this to the names of tables that reference this table's
+    # primary key.
+    join_tables = []
+
+    # Set this to a dict of the valid fields of this object and their
+    # types. Not all fields (e.g., joined fields) may be updated via
+    # sync().
     fields = {}
 
+    # The name of the view that extends objects with tags
+    # e.g. view_tags_name = "view_node_tags"
+    view_tags_name = None
+
+    # Set this to the set of tags that can be returned by the Get function
+    tags = {}
+
+    def __init__(self, api, fields = {}):
+        dict.__init__(self, fields)
+        self.api = api
+        # run the class_init initializer once
+        cls=self.__class__
+        if not hasattr(cls,'class_inited'):
+            cls.class_init (api)
+            cls.class_inited=True # actual value does not matter
+
     def validate(self):
         """
         Validates values. Will validate a value with a custom function
@@ -30,7 +59,7 @@ class Row(dict):
         mandatory_fields = self.api.db.fields(self.table_name, notnull = True, hasdef = False)
         for field in mandatory_fields:
             if not self.has_key(field) or self[field] is None:
-                raise PLCInvalidArgument, field + " must be specified and cannot be unset"
+                raise PLCInvalidArgument, field + " must be specified and cannot be unset in class %s"%self.__class__.__name__
 
         # Validate values before committing
         for key, value in self.iteritems():
@@ -38,30 +67,286 @@ class Row(dict):
                 validate = getattr(self, 'validate_' + key)
                 self[key] = validate(value)
 
-    def sync(self, commit = True):
+    def separate_types(self, items):
+        """
+        Separate a list of different typed objects.
+        Return a list for each type (ints, strs and dicts)
+        """
+
+        if isinstance(items, (list, tuple, set)):
+            ints = filter(lambda x: isinstance(x, (int, long)), items)
+            strs = filter(lambda x: isinstance(x, StringTypes), items)
+            dicts = filter(lambda x: isinstance(x, dict), items)
+            return (ints, strs, dicts)
+        else:
+            raise PLCInvalidArgument, "Can only separate list types"
+
+
+    def associate(self, *args):
+        """
+        Provides a means for high level api calls to associate objects
+        using low level calls.
+        """
+
+        if len(args) < 3:
+            raise PLCInvalidArgumentCount, "auth, field, value must be specified"
+        elif hasattr(self, 'associate_' + args[1]):
+            associate = getattr(self, 'associate_'+args[1])
+            associate(*args)
+        else:
+            raise PLCInvalidArguemnt, "No such associate function associate_%s" % args[1]
+
+    def validate_timestamp (self, timestamp):
+        return Timestamp.sql_validate(timestamp)
+
+    def add_object(self, classobj, join_table, columns = None):
+        """
+        Returns a function that can be used to associate this object
+        with another.
+        """
+
+        def add(self, obj, columns = None, commit = True):
+            """
+            Associate with the specified object.
+            """
+
+            # Various sanity checks
+            assert isinstance(self, Row)
+            assert self.primary_key in self
+            assert join_table in self.join_tables
+            assert isinstance(obj, classobj)
+            assert isinstance(obj, Row)
+            assert obj.primary_key in obj
+            assert join_table in obj.join_tables
+
+            # By default, just insert the primary keys of each object
+            # into the join table.
+            if columns is None:
+                columns = {self.primary_key: self[self.primary_key],
+                           obj.primary_key: obj[obj.primary_key]}
+
+            params = []
+            for name, value in columns.iteritems():
+                params.append(self.api.db.param(name, value))
+
+            self.api.db.do("INSERT INTO %s (%s) VALUES(%s)" % \
+                           (join_table, ", ".join(columns), ", ".join(params)),
+                           columns)
+
+            if commit:
+                self.api.db.commit()
+
+        return add
+
+    add_object = classmethod(add_object)
+
+    def remove_object(self, classobj, join_table):
+        """
+        Returns a function that can be used to disassociate this
+        object with another.
+        """
+
+        def remove(self, obj, commit = True):
+            """
+            Disassociate from the specified object.
+            """
+
+            assert isinstance(self, Row)
+            assert self.primary_key in self
+            assert join_table in self.join_tables
+            assert isinstance(obj, classobj)
+            assert isinstance(obj, Row)
+            assert obj.primary_key in obj
+            assert join_table in obj.join_tables
+
+            self_id = self[self.primary_key]
+            obj_id = obj[obj.primary_key]
+
+            self.api.db.do("DELETE FROM %s WHERE %s = %s AND %s = %s" % \
+                           (join_table,
+                            self.primary_key, self.api.db.param('self_id', self_id),
+                            obj.primary_key, self.api.db.param('obj_id', obj_id)),
+                           locals())
+
+            if commit:
+                self.api.db.commit()
+
+        return remove
+
+    remove_object = classmethod(remove_object)
+
+    # convenience: check in dict (self.fields or self.tags) that a key is writable
+    @staticmethod
+    def is_writable (key,value,dict):
+        # if not mentioned, assume it's writable (e.g. deleted ...)
+        if key not in dict: return True
+        # if mentioned but not linked to a Parameter object, idem
+        if not isinstance(dict[key], Parameter): return True
+        # if not marked ro, it's writable
+        if not dict[key].ro: return True
+        return False
+
+    def db_fields(self, obj = None):
+        """
+        Return only those fields that can be set or updated directly
+        (i.e., those fields that are in the primary table (table_name)
+        for this object, and are not marked as a read-only Parameter.
+        """
+
+        if obj is None: obj = self
+
+        db_fields = self.api.db.fields(self.table_name)
+        return dict ( [ (key,value) for (key,value) in obj.items()
+                        if key in db_fields and
+                        Row.is_writable(key,value,self.fields) ] )
+
+    def tag_fields (self, obj=None):
+        """
+        Return the fields of obj that are mentioned in tags
+        """
+        if obj is None: obj=self
+
+        return dict ( [ (key,value) for (key,value) in obj.iteritems()
+                        if key in self.tags and Row.is_writable(key,value,self.tags) ] )
+
+    # takes as input a list of columns, sort native fields from tags
+    # returns 2 dicts and one list : fields, tags, rejected
+    @classmethod
+    def parse_columns (cls, columns):
+        (fields,tags,rejected)=({},{},[])
+        for column in columns:
+            if column in cls.fields: fields[column]=cls.fields[column]
+            elif column in cls.tags: tags[column]=cls.tags[column]
+            else: rejected.append(column)
+        return (fields,tags,rejected)
+
+    # compute the 'accepts' part of a method, from a list of column names, and a fields dict
+    # use exclude=True to exclude the column names instead
+    # typically accepted_fields (Node.fields,['hostname','model',...])
+    @staticmethod
+    def accepted_fields (update_columns, fields_dict, exclude=False):
+        result={}
+        for (k,v) in fields_dict.iteritems():
+            if (not exclude and k in update_columns) or (exclude and k not in update_columns):
+                result[k]=v
+        return result
+
+    # filter out user-provided fields that are not part of the declared acceptance list
+    # keep it separate from split_fields for simplicity
+    # typically check_fields (<user_provided_dict>,{'hostname':Parameter(str,...),'model':Parameter(..)...})
+    @staticmethod
+    def check_fields (user_dict, accepted_fields):
+# avoid the simple, but silent, version
+#        return dict ([ (k,v) for (k,v) in user_dict.items() if k in accepted_fields ])
+        result={}
+        for (k,v) in user_dict.items():
+            if k in accepted_fields: result[k]=v
+            else: raise PLCInvalidArgument ('Trying to set/change unaccepted key %s'%k)
+        return result
+
+    # given a dict (typically passed to an Update method), we check and sort
+    # them against a list of dicts, e.g. [Node.fields, Node.related_fields]
+    # return is a list that contains n+1 dicts, last one has the rejected fields
+    @staticmethod
+    def split_fields (fields, dicts):
+        result=[]
+        for x in dicts: result.append({})
+        rejected={}
+        for (field,value) in fields.iteritems():
+            found=False
+            for i in range(len(dicts)):
+                candidate_dict=dicts[i]
+                if field in candidate_dict.keys():
+                    result[i][field]=value
+                    found=True
+                    break
+            if not found: rejected[field]=value
+        result.append(rejected)
+        return result
+
+    ### class initialization : create tag-dependent cross view if needed
+    @classmethod
+    def tagvalue_view_name (cls, tagname):
+        return "tagvalue_view_%s_%s"%(cls.primary_key,tagname)
+
+    @classmethod
+    def tagvalue_view_create_sql (cls,tagname):
+        """
+        returns a SQL sentence that creates a view named after the primary_key and tagname,
+        with 2 columns
+        (*) column 1: primary_key
+        (*) column 2: actual tag value, renamed into tagname
+        """
+
+        if not cls.view_tags_name:
+            raise Exception, 'WARNING: class %s needs to set view_tags_name'%cls.__name__
+
+        table_name=cls.table_name
+        primary_key=cls.primary_key
+        view_tags_name=cls.view_tags_name
+        tagvalue_view_name=cls.tagvalue_view_name(tagname)
+        return 'CREATE OR REPLACE VIEW %(tagvalue_view_name)s ' \
+            'as SELECT %(table_name)s.%(primary_key)s,%(view_tags_name)s.value as "%(tagname)s" ' \
+            'from %(table_name)s right join %(view_tags_name)s using (%(primary_key)s) ' \
+            'WHERE tagname = \'%(tagname)s\';'%locals()
+
+    @classmethod
+    def class_init (cls,api):
+        cls.tagvalue_views_create (api)
+
+    @classmethod
+    def tagvalue_views_create (cls,api):
+        if not cls.tags: return
+        for tagname in cls.tags.keys():
+            api.db.do(cls.tagvalue_view_create_sql (tagname))
+        api.db.commit()
+
+    def __eq__(self, y):
+        """
+        Compare two objects.
+        """
+
+        # Filter out fields that cannot be set or updated directly
+        # (and thus would not affect equality for the purposes of
+        # deciding if we should sync() or not).
+        x = self.db_fields()
+        y = self.db_fields(y)
+        return dict.__eq__(x, y)
+
+    # validate becomes optional on sept. 2010
+    # we find it useful to use DeletePerson on duplicated entries
+    def sync(self, commit = True, insert = None, validate=True):
         """
         Flush changes back to the database.
         """
 
         # Validate all specified fields
-        self.validate()
+        if validate: self.validate()
 
         # Filter out fields that cannot be set or updated directly
-        all_fields = self.api.db.fields(self.table_name)
-        fields = dict(filter(lambda (key, value): \
-                             key in all_fields and \
-                             (key not in self.fields or \
-                              not isinstance(self.fields[key], Parameter) or \
-                              not self.fields[key].ro),
-                             self.items()))
+        db_fields = self.db_fields()
 
         # Parameterize for safety
-        keys = fields.keys()
-        values = [self.api.db.param(key, value) for (key, value) in fields.items()]
+        keys = db_fields.keys()
+        values = [self.api.db.param(key, value) for (key, value) in db_fields.items()]
+
+        # If the primary key (usually an auto-incrementing serial
+        # identifier) has not been specified, or the primary key is the
+        # only field in the table, or insert has been forced.
+        if not self.has_key(self.primary_key) or \
+           keys == [self.primary_key] or \
+           insert is True:
 
-        if not self.has_key(self.primary_key):
+            # If primary key id is a serial int and it isnt included, get next id
+            if self.fields[self.primary_key].type in (IntType, LongType) and \
+               self.primary_key not in self:
+                pk_id = self.api.db.next_id(self.table_name, self.primary_key)
+                self[self.primary_key] = pk_id
+                db_fields[self.primary_key] = pk_id
+                keys = db_fields.keys()
+                values = [self.api.db.param(key, value) for (key, value) in db_fields.items()]
             # Insert new row
-            sql = "INSERT INTO %s (%s) VALUES (%s);" % \
+            sql = "INSERT INTO %s (%s) VALUES (%s)" % \
                   (self.table_name, ", ".join(keys), ", ".join(values))
         else:
             # Update existing row
@@ -72,40 +357,82 @@ class Row(dict):
                   (self.primary_key,
                    self.api.db.param(self.primary_key, self[self.primary_key]))
 
-        self.api.db.do(sql, fields)
-
-        if not self.has_key(self.primary_key):
-            self[self.primary_key] = self.api.db.last_insert_id(self.table_name, self.primary_key)
+        self.api.db.do(sql, db_fields)
 
         if commit:
             self.api.db.commit()
 
     def delete(self, commit = True):
         """
-        Delete row from its primary table.
+        Delete row from its primary table, and from any tables that
+        reference it.
         """
 
         assert self.primary_key in self
 
-        sql = "DELETE FROM %s" % self.table_name + \
-              " WHERE %s = %s" % \
-              (self.primary_key,
-               self.api.db.param(self.primary_key, self[self.primary_key]))
+        for table in self.join_tables + [self.table_name]:
+            if isinstance(table, tuple):
+                key = table[1]
+                table = table[0]
+            else:
+                key = self.primary_key
 
-        self.api.db.do(sql, self)
+            sql = "DELETE FROM %s WHERE %s = %s" % \
+                  (table, key,
+                   self.api.db.param(self.primary_key, self[self.primary_key]))
+
+            self.api.db.do(sql, self)
 
         if commit:
             self.api.db.commit()
 
-class Table(dict):
+class Table(list):
     """
     Representation of row(s) in a database table.
     """
 
+    def __init__(self, api, classobj, columns = None):
+        self.api = api
+        self.classobj = classobj
+        self.rows = {}
+
+        if columns is None:
+            columns = classobj.fields
+            tag_columns={}
+        else:
+            (columns,tag_columns,rejected) = classobj.parse_columns(columns)
+            if not columns and not tag_columns:
+                raise PLCInvalidArgument, "No valid return fields specified for class %s"%classobj.__name__
+            if rejected:
+                raise PLCInvalidArgument, "unknown column(s) specified %r in %s"%(rejected,classobj.__name__)
+
+        self.columns = columns
+        self.tag_columns = tag_columns
+
     def sync(self, commit = True):
         """
         Flush changes back to the database.
         """
 
-        for row in self.values():
+        for row in self:
             row.sync(commit)
+
+    def selectall(self, sql, params = None):
+        """
+        Given a list of rows from the database, fill ourselves with
+        Row objects.
+        """
+
+        for row in self.api.db.selectall(sql, params):
+            obj = self.classobj(self.api, row)
+            self.append(obj)
+
+    def dict(self, key_field = None):
+        """
+        Return ourself as a dict keyed on key_field.
+        """
+
+        if key_field is None:
+            key_field = self.classobj.primary_key
+
+        return dict([(obj[key_field], obj) for obj in self])