firebird-qa/tests/bugs/core_6018_test.py

#coding:utf-8
#
# id:           bugs.core_6018
# title:        Make it possible to start multiple transactions (possibly in different attachments) using the same initial transaction snapshot
# decription:
#                   We open first connect using FDB and set custom transaction parameter block which is used to start SNAPSHOT transaction.
#                   Within this first transaction (tx1a) we insert into test table record with value = -2 and commit this Tx.
#                   Then we do start next transaction (also SNAPSHOT; its name = 'tx1b') and obtain value of RDB$GET_CONTEXT('SYSTEM', 'SNAPSHOT_NUMBER').
#                   Also, in this second 'tx1b' we add one more record into table with value = -1 using autonomous transaction --> BOTH records should be seen
#                   in another attachment that will be started after this moment.
#                   But if this (new) attachment will start Tx with requirement to use snapshot that was for Tx1a then it must see only FIRST record with value=-2.
#
#                   We launch then ISQL for establish another transaction and make it perform two transactions:
#                   1) 'set transaction snapshot' --> must extract both records from test table
#                   === vs ===
#                   2) 'set transaction snapshot at number %(snap_num)s' --> must extract only FIRST record with value = -2.
#
#                   THis is done TWO times: when based snapshot is KNOWN (i.e. tx1b is alive) and after tx1b is committed and base is unknown.
#                   Second ISQL launch must issue error:
#                       Statement failed, SQLSTATE = 0B000
#                       Transaction's base snapshot number does not exist
#
#                   Checked on: 4.0.0.1457 (SS,CS) -- works fine.
#
# tracker_id:   CORE-6018
# min_versions: ['4.0']
# versions:     4.0
# qmid:         None

import pytest
from firebird.qa import db_factory, python_act, Action
from firebird.driver import tpb, Isolation

# version: 4.0
# resources: None

substitutions_1 = []

init_script_1 = """
    recreate table tsn (sn int);
    commit;
"""

db_1 = db_factory(sql_dialect=3, init=init_script_1)

# test_script_1
#---
# import os
#  import re
#  import time
#  import subprocess
#  from subprocess import Popen
#  from fdb import services
#
#  os.environ["ISC_USER"] = user_name
#  os.environ["ISC_PASSWORD"] = user_password
#  db_conn.close()
#
#  customTPB = ( [ fdb.isc_tpb_concurrency, fdb.isc_tpb_nowait ] )
#  con1 = fdb.connect( dsn = dsn )
#
#  tx1a=con1.trans( default_tpb = customTPB )
#
#  cur1=tx1a.cursor()
#  cur1.execute('insert into tsn(sn) values( -2 )' )
#  tx1a.commit()
#
#  sql_get_sn='''
#      execute block returns(o_sn bigint) as
#      begin
#          o_sn = RDB$GET_CONTEXT('SYSTEM', 'SNAPSHOT_NUMBER');
#          suspend;
#
#          in autonomous transaction do
#          insert into tsn(sn) values( -1 );
#      end
#  '''
#
#  tx1b=con1.trans( default_tpb = customTPB )
#  cur1=tx1b.cursor()
#  cur1.execute( sql_get_sn )
#
#  snap_num = -1
#  for r in cur1:
#      snap_num = r[0]
#      # print( r[0] )
#
#  for m in ('yet exists', 'does not exists'):
#      sql_chk_sn='''
#          -- NB!! looks strange but it seems that this 'SET BAIL ON' does not work here because
#          -- both records will be extracted in any case. // todo later: check it!
#          --set bail on;
#          set count on;
#          commit;
#          set transaction snapshot;
#          select 'Tx base snapshot: %(m)s' as msg, t.sn as set_tx_snapshot_without_num from tsn t order by sn;
#          commit;
#          set transaction snapshot at number %(snap_num)s;
#          select 'Tx base snapshot: %(m)s' as msg, t.sn as set_tx_snapshot_at_number_N from tsn t order by sn;
#          commit;
#          quit;
#      ''' % ( locals() )
#
#      #print(sql_chk_sn)
#
#      runProgram('isql', [ dsn, '-q' ], sql_chk_sn)
#      if tx1b:
#          tx1b.commit()
#
#  cur1.close()
#  con1.close()
#
#
#---

act_1 = python_act('db_1', substitutions=substitutions_1)

expected_stdout_1_a = """
    MSG                          SET_TX_SNAPSHOT_WITHOUT_NUM
    ============================ ===========================
    Tx base snapshot: yet exists                          -2
    Tx base snapshot: yet exists                          -1
    Records affected: 2
    MSG                          SET_TX_SNAPSHOT_AT_NUMBER_N
    ============================ ===========================
    Tx base snapshot: yet exists                          -2
    Records affected: 1
"""

expected_stdout_1_b = """
    MSG                               SET_TX_SNAPSHOT_WITHOUT_NUM
    ================================= ===========================
    Tx base snapshot: does not exists                          -2
    Tx base snapshot: does not exists                          -1
    Records affected: 2
    MSG                               SET_TX_SNAPSHOT_AT_NUMBER_N
    ================================= ===========================
    Tx base snapshot: does not exists                          -2
    Tx base snapshot: does not exists                          -1
    Records affected: 2
"""

expected_stderr_1 = """
    Statement failed, SQLSTATE = 0B000
    Transaction's base snapshot number does not exist
"""

@pytest.mark.version('>=4.0')
def test_1(act_1: Action):
    custom_tpb = tpb(isolation=Isolation.CONCURRENCY, lock_timeout=0)
    with act_1.db.connect() as con1:
        tx1a = con1.transaction_manager(custom_tpb)
        tx1a.begin()
        cur1 = tx1a.cursor()
        cur1.execute('insert into tsn (sn) values( -2 )')
        tx1a.commit()
        #
        sql_get_sn = """
            execute block returns(o_sn bigint) as
            begin
                o_sn = RDB$GET_CONTEXT('SYSTEM', 'SNAPSHOT_NUMBER');
                suspend;

                in autonomous transaction do
                insert into tsn(sn) values( -1 );
            end
        """
        tx1b = con1.transaction_manager(custom_tpb)
        cur1 = tx1b.cursor()
        snap_num = cur1.execute(sql_get_sn).fetchone()[0]
        #
        for msg, expect_out, expect_err in [('yet exists', expected_stdout_1_a, ''),
                                            ('does not exists', expected_stdout_1_b, expected_stderr_1)]:
            sql_chk_sn = f"""
                -- NB!! looks strange but it seems that this 'SET BAIL ON' does not work here because
                -- both records will be extracted in any case. // todo later: check it!
                --set bail on;
                set count on;
                commit;
                set transaction snapshot;
                select 'Tx base snapshot: {msg}' as msg, t.sn as set_tx_snapshot_without_num from tsn t order by sn;
                commit;
                set transaction snapshot at number {snap_num};
                select 'Tx base snapshot: {msg}' as msg, t.sn as set_tx_snapshot_at_number_N from tsn t order by sn;
                commit;
                quit;
            """
            act_1.reset()
            act_1.expected_stdout = expect_out
            act_1.expected_stderr = expect_err
            act_1.isql(switches=['-q'], input=sql_chk_sn)
            if tx1b.is_active():
                tx1b.commit()
            assert act_1.clean_stdout == act_1.clean_expected_stdout