-from collections import OrderedDict
-import sqlparse
+from moz_sql_parser import parse
+import re
import tables
_connector_type = 'pytables'
h5file = tables.open_file(path)
for table in filter(lambda node: not(isinstance(node, tables.group.Group)), h5file):
- colnames = []
+ colnames = ['value']
if isinstance(table, tables.table.Table):
colnames = table.colnames
h5file.close()
return h5tables, views, _connector_type
-def _parse_sql(sql):
- parsed = sqlparse.parse(sql)
- stmt = parsed[0]
- parsed_sql = {}
- current_keyword = ""
- for token in stmt.tokens:
- if token.is_keyword:
- if current_keyword in parsed_sql and parsed_sql[current_keyword] == '':
- # Check composed keywords like 'order by'
- del parsed_sql[current_keyword]
- current_keyword += " " + str(token)
- else:
- current_keyword = str(token)
- parsed_sql[current_keyword] = ""
- elif type(token) is sqlparse.sql.Where:
- parsed_sql['where'] = token
- else:
- if not token.is_whitespace:
- parsed_sql[current_keyword] += str(token)
- return parsed_sql
+def _parse_sql(sql, params):
+ # Table name
+ sql = re.sub('(?i)from \[(.*)]', 'from "\g<1>"', sql)
+ # Params
+ for param in params:
+ sql = sql.replace(":" + param, param)
-_operators = {
- '=': '==',
-}
+ try:
+ parsed = parse(sql)
+ except:
+ # Propably it's a PyTables expression
+ for token in ['group by', 'order by', 'limit', '']:
+ res = re.search('(?i)where (.*)' + token, sql)
+ if res:
+ modified_sql = re.sub('(?i)where (.*)(' + token + ')', '\g<2>', sql)
+ parsed = parse(modified_sql)
+ parsed['where'] = res.group(1).strip()
+ break
-def _translate_condition(table, condition, params):
- field = condition.left.get_real_name()
+ # Always a list of fields
+ if type(parsed['select']) is not list:
+ parsed['select'] = [parsed['select']]
- operator = list(filter(lambda t: t.ttype == sqlparse.tokens.Comparison, condition.tokens))[0]
- if operator.value in _operators:
- operator = _operators[operator.value]
- else:
- operator = operator.value
+ return parsed
- value = condition.right.value
- if value.startswith(':'):
- # Value is a parameters
- value = value[1:]
- if value in params:
- # Cast value to the column type
- coltype = table.coltypes[field]
- if coltype == 'string':
- params[value] = str(params[value])
- elif coltype.startswith('int'):
- params[value] = int(params[value])
- elif coltype.startswith('float'):
- params[value] = float(params[value])
-
- translated = "{left} {operator} {right}".format(left=field, operator=operator, right=value)
- return translated, params
+_operators = {
+ 'eq': '==',
+ 'neq': '!=',
+ 'gt': '>',
+ 'gte': '>=',
+ 'lt': '<',
+ 'lte': '<=',
+ 'and': '&',
+ 'or': '|',
+}
class Connection:
def __init__(self, path):
self.path = path
self.h5file = tables.open_file(path)
- def execute(self, sql, params=None, truncate=False):
+ def execute(self, sql, params=None, truncate=False, page_size=None, max_returned_rows=None):
if params is None:
params = {}
rows = []
truncated = False
description = []
- parsed_sql = _parse_sql(sql)
- table = self.h5file.get_node(parsed_sql['from'][1:-1])
+ parsed_sql = _parse_sql(sql, params)
+
+ if parsed_sql['from'] == 'sqlite_master':
+ rows = self._execute_datasette_query(sql, params)
+ description = (('value',))
+ return rows, truncated, description
+
+ table = self.h5file.get_node(parsed_sql['from'])
table_rows = []
- fields = parsed_sql['select'].split(',')
+ fields = parsed_sql['select']
+ colnames = ['value']
+ if type(table) is tables.table.Table:
+ colnames = table.colnames
query = ''
start = 0
end = table.nrows
# Use 'where' statement or get all the rows
+ def _cast_param(field, pname):
+ # Cast value to the column type
+ coltype = table.dtype.name
+ if type(table) is tables.table.Table:
+ coltype = table.coltypes[field]
+ fcast = None
+ if coltype == 'string':
+ fcast = str
+ elif coltype.startswith('int'):
+ fcast = int
+ elif coltype.startswith('float'):
+ fcast = float
+ if fcast:
+ params[pname] = fcast(params[pname])
+
+ def _translate_where(where):
+ # Translate SQL to PyTables expression
+ nonlocal start, end
+ expr = ''
+ operator = list(where)[0]
+
+ if operator in ['and', 'or']:
+ subexpr = [_translate_where(e) for e in where[operator]]
+ subexpr = filter(lambda e: e, subexpr)
+ subexpr = ["({})".format(e) for e in subexpr]
+ expr = " {} ".format(_operators[operator]).join(subexpr)
+ elif operator == 'exists':
+ pass
+ elif where == {'eq': ['rowid', 'p0']}:
+ start = int(params['p0'])
+ end = start + 1
+ elif where == {'gt': ['rowid', 'p0']}:
+ start = int(params['p0']) + 1
+ else:
+ left, right = where[operator]
+ if left in params:
+ _cast_param(right, left)
+ elif right in params:
+ _cast_param(left, right)
+
+ expr = "{left} {operator} {right}".format(left=left, operator=_operators.get(operator, operator), right=right)
+
+ return expr
+
if 'where' in parsed_sql:
- try:
- conditions = []
- for condition in parsed_sql['where'].get_sublists():
- if str(condition) == '"rowid"=:p0':
- start = int(params['p0'])
- end = start + 1
- else:
- translated, params = _translate_condition(table, condition, params)
- conditions.append(translated)
- if conditions:
- query = ') & ('.join(conditions)
- query = '(' + query + ')'
- except:
- # Probably it's a PyTables query
- query = str(parsed_sql['where'])[6:] # without where keyword
+ if type(parsed_sql['where']) is dict:
+ query = _translate_where(parsed_sql['where'])
+ else:
+ query = parsed_sql['where']
# Limit number of rows
+ limit = None
if 'limit' in parsed_sql:
- max_rows = int(parsed_sql['limit'])
- if end - start > max_rows:
- end = start + max_rows
+ limit = int(parsed_sql['limit'])
+
+ # Truncate if needed
+ if page_size and max_returned_rows and truncate:
+ if max_returned_rows == page_size:
+ max_returned_rows += 1
# Execute query
if query:
table_rows = table.iterrows(start, end)
# Prepare rows
- if len(fields) == 1 and fields[0] == 'count(*)':
- rows.append(Row({fields[0]: int(table.nrows)}))
+ def normalize_field_value(value):
+ if type(value) is bytes:
+ return value.decode('utf-8')
+ elif not type(value) in (int, float, complex):
+ return str(value)
+ else:
+ return value
+
+ def make_get_rowid():
+ if type(table) is tables.table.Table:
+ def get_rowid(row):
+ return int(row.nrow)
+ else:
+ rowid = start - 1
+ def get_rowid(row):
+ nonlocal rowid
+ rowid += 1
+ return rowid
+ return get_rowid
+
+ def make_get_row_value():
+ if type(table) is tables.table.Table:
+ def get_row_value(row, field):
+ return row[field]
+ else:
+ def get_row_value(row, field):
+ return row
+ return get_row_value
+
+ if len(fields) == 1 and type(fields[0]['value']) is dict and \
+ fields[0]['value'].get('count') == '*':
+ rows.append(Row({'count(*)': int(table.nrows)}))
else:
+ get_rowid = make_get_rowid()
+ get_row_value = make_get_row_value()
+ count = 0
for table_row in table_rows:
+ count += 1
+ if limit and count > limit:
+ break
+ if truncate and max_returned_rows and count > max_returned_rows:
+ truncated = True
+ break
row = Row()
for field in fields:
- if field == 'rowid':
- row[field] = int(table_row.nrow)
- elif field == '*':
- for col in table.colnames:
- value = table_row[col]
- if type(value) is bytes:
- value = value.decode('utf-8')
- row[col] = value
+ field_name = field['value']
+ if type(field_name) is dict and 'distinct' in field_name:
+ field_name = field_name['distinct']
+ if field_name == 'rowid':
+ row['rowid'] = get_rowid(table_row)
+ elif field_name == '*':
+ for col in colnames:
+ row[col] = normalize_field_value(get_row_value(table_row, col))
else:
- row[field] = table_row[field]
+ row[field_name] = normalize_field_value(get_row_value(table_row, field_name))
rows.append(row)
# Prepare query description
- for field in fields:
+ for field in [f['value'] for f in fields]:
if field == '*':
- for col in table.colnames:
+ for col in colnames:
description.append((col,))
else:
description.append((field,))
# Return the rows
- if truncate:
- return rows, truncated, tuple(description)
+ return rows, truncated, tuple(description)
+
+ def _execute_datasette_query(self, sql, params):
+ "Datasette special queries for getting tables info"
+ if sql == "SELECT count(*) from sqlite_master WHERE type = 'view' and name=:n":
+ row = Row()
+ row['count(*)'] = 0
+ return [row]
+ elif sql == 'select sql from sqlite_master where name = :n and type="table"':
+ try:
+ table = self.h5file.get_node(params['n'])
+ colnames = ['value']
+ if type(table) is tables.table.Table:
+ colnames = table.colnames
+ row = Row()
+ row['sql'] = 'CREATE TABLE {} ({})'.format(params['n'], ", ".join(colnames))
+ return [row]
+ except:
+ return []
+ else:
+ raise Exception("SQLite queries cannot be executed with this connector")
+
+class Row(list):
+ def __init__(self, values=None):
+ self.labels = []
+ self.values = []
+ if values:
+ for idx in values:
+ self.__setitem__(idx, values[idx])
+
+ def __setitem__(self, idx, value):
+ if type(idx) is str:
+ if idx in self.labels:
+ self.values[self.labels.index(idx)] = value
+ else:
+ self.labels.append(idx)
+ self.values.append(value)
else:
- return rows
+ self.values[idx] = value
-class Row(OrderedDict):
- def __getitem__(self, label):
- if type(label) is int:
- return super(OrderedDict, self).__getitem__(list(self.keys())[label])
+ def __getitem__(self, idx):
+ if type(idx) is str:
+ return self.values[self.labels.index(idx)]
else:
- return super(OrderedDict, self).__getitem__(label)
+ return self.values[idx]
def __iter__(self):
- return self.values().__iter__()
+ return self.values.__iter__()
projects / datasette-pytables.git / blobdiff