def execute_select_plain(etcd_client, tree, db):
"""Execute SELECT that reads rows from table."""
result_columns = prepare_columns(tree)
result_set = ResultSet(result_columns)
table_columns = get_table_columns(etcd_client, db, tree.table)
last_row = None
for primary_key in list_table(etcd_client, db, tree.table):
table_row = get_row_by_primary_key(etcd_client, db, tree.table,
primary_key)
if tree.where:
expr = tree.where
if eval_expr((table_columns, table_row), expr)[1]:
row = Row(eval_row(table_columns, table_row, tree),
etcd_index=table_row.etcd_index,
modified_index=table_row.modified_index)
result_set.add_row(row)
last_row = table_row
else:
row = Row(eval_row(table_columns, table_row, tree),
etcd_index=table_row.etcd_index,
modified_index=table_row.modified_index)
result_set.add_row(row)
last_row = table_row
g_function, pos = group_function(table_columns, last_row, tree)
if g_function:
result_set = group_result_set(g_function, result_set, last_row, tree,
pos)
return result_set
def execute_update(etcd_client, tree, db):
"""Execute UPDATE query"""
affected_rows = 0
table_columns = get_table_columns(etcd_client, db, tree.table)
for primary_key in list_table(etcd_client, db, tree.table):
table_row = get_row_by_primary_key(etcd_client, db, tree.table,
primary_key)
key = '/{db}/{tbl}/{pk}'.format(db=db, tbl=tree.table, pk=primary_key)
row = {}
for column in table_columns:
index = table_columns.index(column)
row[str(column)] = table_row[index]
for update_fields in tree.expressions:
field_name, field_expression = update_fields
field_value = eval_expr(table_row, field_expression)
# print('Update %s with %s' % (field_name, field_value[1]))
row[field_name] = field_value[1]
if tree.where:
if eval_expr((table_columns, table_row), tree.where)[1]:
_update_key(etcd_client, key, json.dumps(row))
affected_rows += 1
else:
_update_key(etcd_client, key, json.dumps(row))
affected_rows += 1
return affected_rows
def execute_wait(etcd_client, tree, db):
"""Execute WAIT.
:param etcd_client: Etcd client.
:type etcd_client: Client
:param tree: Parsing tree.
:type tree: SQLTree
:param db: Current database.
:type db: str
"""
result_columns = prepare_columns(tree)
result_set = ResultSet(result_columns)
table_columns = get_table_columns(etcd_client, db, tree.table)
for primary_key in list_table(etcd_client, db, tree.table):
table_row = get_row_by_primary_key(etcd_client, db, tree.table,
primary_key)
etcd_index = table_row.etcd_index
if tree.where:
expr = tree.where
try:
wait_index = tree.options['after']
except KeyError:
wait_index = etcd_index + 1
if eval_expr((table_columns, table_row), expr)[1]:
start = time.time()
while True:
if time.time() > start + WAIT_WAIT_TIMEOUT:
raise InternalError('Wait timeout %d '
'seconds expired' %
WAIT_WAIT_TIMEOUT)
try:
new_row = get_row_by_primary_key(etcd_client,
db,
tree.table,
primary_key,
wait=True,
wait_index=wait_index)
break
except KeyError:
wait_index += 1
row = Row(eval_row(table_columns, new_row, tree),
etcd_index=new_row.etcd_index,
modified_index=new_row.modified_index)
result_set.add_row(row)
else:
row = Row(eval_row(table_columns, table_row, tree),
etcd_index=etcd_index,
modified_index=etcd_index)
result_set.add_row(row)
return result_set
def fix_tree_star(tree, etcd_client, db, tbl):
"""If parsing tree contains [["*", null], null] expression it means
the query was SELECT * . So, the expressions needs to be replaced
with actual field names.
"""
if tree.expressions == [(("*", None), None)]:
tree.expressions = []
for field in get_table_columns(etcd_client, db, tbl):
tree.expressions.append(
(('bool_primary', ('predicate', ('bit_expr', ('simple_expr',
('IDENTIFIER',
str(field)))))),
None))
return tree
def execute_delete(etcd_client, tree, db):
"""Execute DELETE query"""
affected_rows = 0
table_columns = get_table_columns(etcd_client, db, tree.table)
for primary_key in list_table(etcd_client, db, tree.table):
table_row = get_row_by_primary_key(etcd_client, db, tree.table,
primary_key)
key = "/{db}/{tbl}/{pk}".format(db=db, tbl=tree.table, pk=primary_key)
if tree.where:
expr = tree.where
if eval_expr((table_columns, table_row), expr)[1]:
_delete_key(etcd_client, key)
affected_rows += 1
else:
_delete_key(etcd_client, key)
affected_rows += 1
return affected_rows