sfa/util/table.py

   1 #
   2 # implements support for SFA records stored in db tables
   3 #
   4 # TODO: Use existing PLC database methods? or keep this separate?
   5
   6 from types import StringTypes
   7
   8 from sfa.util.config import Config
   9 from sfa.util.parameter import Parameter
  10 from sfa.util.filter import Filter
  11 from sfa.util.PostgreSQL import PostgreSQL
  12 from sfa.util.record import SfaRecord, AuthorityRecord, NodeRecord, SliceRecord, UserRecord
  13
  14 class SfaTable(list):
  15
  16     SFA_TABLE_PREFIX = "sfa"
  17
  18     def __init__(self, record_filter = None):
  19
  20         # pgsql doesn't like table names with "." in them, to replace it with "$"
  21         self.tablename = SfaTable.SFA_TABLE_PREFIX
  22         self.config = Config()
  23         self.db = PostgreSQL(self.config)
  24
  25         if record_filter:
  26             records = self.find(record_filter)
  27             for record in records:
  28                 self.append(record)
  29
  30     def exists(self):
  31         sql = "SELECT * from pg_tables"
  32         tables = self.db.selectall(sql)
  33         tables = filter(lambda row: row['tablename'].startswith(self.SFA_TABLE_PREFIX), tables)
  34         if tables:
  35             return True
  36         return False
  37
  38     def db_fields(self, obj=None):
  39
  40         db_fields = self.db.fields(self.SFA_TABLE_PREFIX)
  41         return dict( [ (key,value) for (key, value) in obj.iteritems() \
  42                         if key in db_fields and
  43                         self.is_writable(key, value, SfaRecord.fields)] )
  44
  45     @staticmethod
  46     def is_writable (key,value,dict):
  47         # if not mentioned, assume it's writable (e.g. deleted ...)
  48         if key not in dict: return True
  49         # if mentioned but not linked to a Parameter object, idem
  50         if not isinstance(dict[key], Parameter): return True
  51         # if not marked ro, it's writable
  52         if not dict[key].ro: return True
  53
  54         return False
  55
  56
  57     def create(self):
  58
  59         querystr = "CREATE TABLE " + self.tablename + " ( \
  60                 record_id serial PRIMARY KEY , \
  61                 hrn text NOT NULL, \
  62                 authority text NOT NULL, \
  63                 peer_authority text, \
  64                 gid text, \
  65                 type text NOT NULL, \
  66                 pointer integer, \
  67                 date_created timestamp without time zone NOT NULL DEFAULT CURRENT_TIMESTAMP, \
  68                 last_updated timestamp without time zone NOT NULL DEFAULT CURRENT_TIMESTAMP);"
  69         template = "CREATE INDEX %s_%s_idx ON %s (%s);"
  70         indexes = [template % ( self.tablename, field, self.tablename, field) \
  71                    for field in ['hrn', 'type', 'authority', 'peer_authority', 'pointer']]
  72         # IF EXISTS doenst exist in postgres < 8.2
  73         try:
  74             self.db.do('DROP TABLE IF EXISTS ' + self.tablename)
  75         except:
  76             try:
  77                 self.db.do('DROP TABLE' + self.tablename)
  78             except:
  79                 pass
  80
  81         self.db.do(querystr)
  82         for index in indexes:
  83             self.db.do(index)
  84
  85         self.db.commit()
  86
  87     def remove(self, record):
  88         params = {'record_id': record['record_id']}
  89         template = "DELETE FROM %s " % self.tablename
  90         sql = template + "WHERE record_id = %(record_id)s"
  91         self.db.do(sql, params)
  92
  93         # if this is a site, remove all records where 'authority' == the
  94         # site's hrn
  95         if record['type'] == 'authority':
  96             params = {'authority': record['hrn']}
  97             sql = template + "WHERE authority = %(authority)s"
  98             self.db.do(sql, params)
  99         self.db.commit()
 100
 101     def insert(self, record):
 102         db_fields = self.db_fields(record)
 103         keys = db_fields.keys()
 104         values = [self.db.param(key, value) for (key, value) in db_fields.iteritems()]
 105         query_str = "INSERT INTO " + self.tablename + \
 106                        "(" + ",".join(keys) + ") " + \
 107                        "VALUES(" + ",".join(values) + ")"
 108         self.db.do(query_str, db_fields)
 109         self.db.commit()
 110         result = self.find({'hrn': record['hrn'], 'type': record['type'], 'peer_authority': record['peer_authority']})
 111         if not result:
 112             record_id = None
 113         elif isinstance(result, list):
 114             record_id = result[0]['record_id']
 115         else:
 116             record_id = result['record_id']
 117
 118         return record_id
 119
 120     def update(self, record):
 121         db_fields = self.db_fields(record)
 122         keys = db_fields.keys()
 123         values = [self.db.param(key, value) for (key, value) in db_fields.iteritems()]
 124         columns = ["%s = %s" % (key, value) for (key, value) in zip(keys, values)]
 125         query_str = "UPDATE %s SET %s WHERE record_id = %s" % \
 126                     (self.tablename, ", ".join(columns), record['record_id'])
 127         self.db.do(query_str, db_fields)
 128         self.db.commit()
 129
 130     def quote_string(self, value):
 131         return str(self.db.quote(value))
 132
 133     def quote(self, value):
 134         return self.db.quote(value)
 135
 136     def find(self, record_filter = None, columns=None):
 137         if not columns:
 138             columns = "*"
 139         else:
 140             columns = ",".join(columns)
 141         sql = "SELECT %s FROM %s WHERE True " % (columns, self.tablename)
 142
 143         if isinstance(record_filter, (list, tuple, set)):
 144             ints = filter(lambda x: isinstance(x, (int, long)), record_filter)
 145             strs = filter(lambda x: isinstance(x, StringTypes), record_filter)
 146             record_filter = Filter(SfaRecord.all_fields, {'record_id': ints, 'hrn': strs})
 147             sql += "AND (%s) %s " % record_filter.sql("OR")
 148         elif isinstance(record_filter, dict):
 149             record_filter = Filter(SfaRecord.all_fields, record_filter)
 150             sql += " AND (%s) %s" % record_filter.sql("AND")
 151         elif isinstance(record_filter, StringTypes):
 152             record_filter = Filter(SfaRecord.all_fields, {'hrn':[record_filter]})
 153             sql += " AND (%s) %s" % record_filter.sql("AND")
 154         elif isinstance(record_filter, int):
 155             record_filter = Filter(SfaRecord.all_fields, {'record_id':[record_filter]})
 156             sql += " AND (%s) %s" % record_filter.sql("AND")
 157
 158         results = self.db.selectall(sql)
 159         if isinstance(results, dict):
 160             results = [results]
 161         return results
 162
 163     def findObjects(self, record_filter = None, columns=None):
 164
 165         results = self.find(record_filter, columns)
 166         result_rec_list = []
 167         for result in results:
 168             if result['type'] in ['authority']:
 169                 result_rec_list.append(AuthorityRecord(dict=result))
 170             elif result['type'] in ['node']:
 171                 result_rec_list.append(NodeRecord(dict=result))
 172             elif result['type'] in ['slice']:
 173                 result_rec_list.append(SliceRecord(dict=result))
 174             elif result['type'] in ['user']:
 175                 result_rec_list.append(UserRecord(dict=result))
 176             else:
 177                 result_rec_list.append(SfaRecord(dict=result))
 178         return result_rec_list
 179
 180
 181     def drop(self):
 182         try:
 183             self.db.do('DROP TABLE IF EXISTS ' + self.tablename)
 184             self.db.commit()
 185         except:
 186             try:
 187                 self.db.do('DROP TABLE ' + self.tablename)
 188                 self.db.commit()
 189             except:
 190                 pass
 191
 192     def sfa_records_purge(self):
 193         self.drop()