Filter fields with conditions from datasette forms

[datasette-pytables.git] / datasette_pytables / __init__.py

diff --git a/datasette_pytables/__init__.py b/datasette_pytables/__init__.py
index d44c9f93485e4e187c4ec06f3565da0df6723684..217214f6f4d7ece9b9566e8018f85ee85c5ee47f 100644 (file)
--- a/datasette_pytables/__init__.py
+++ b/datasette_pytables/__init__.py
@@ -1,6 +1,6 @@
-import tables
-import sqlparse
 from collections import OrderedDict
+import sqlparse
+import tables
 
 _connector_type = 'pytables'
 
@@ -43,17 +43,51 @@ def _parse_sql(sql):
             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
 
+_operators = {
+    '=': '==',
+}
+
+def _translate_condition(table, condition, params):
+    field = condition.left.get_real_name()
+
+    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
+
+    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
+
 class Connection:
     def __init__(self, path):
         self.path = path
         self.h5file = tables.open_file(path)
 
     def execute(self, sql, params=None, truncate=False):
+        if params is None:
+            params = {}
         rows = []
         truncated = False
         description = []
@@ -65,7 +99,22 @@ class Connection:
 
         # Use 'where' statement or get all the rows
         if 'where' in parsed_sql:
-            pass
+            query = []
+            start = 0
+            end = table.nrows
+            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)
+                    query.append(translated)
+            if query:
+                query = ') & ('.join(query)
+                query = '(' + query + ')'
+                table_rows = table.where(query, params, start, end)
+            else:
+                table_rows = table.iterrows(start, end)
         else:
             table_rows = table.iterrows()
 
@@ -80,7 +129,10 @@ class Connection:
                         row[field] = table_row.nrow
                     elif field == '*':
                         for col in table.colnames:
-                            row[col] = table_row[col]
+                            value = table_row[col]
+                            if type(value) is bytes:
+                                value = value.decode('utf-8')
+                            row[col] = value
                     else:
                         row[field] = table_row[field]
                 rows.append(row)
@@ -93,6 +145,7 @@ class Connection:
             else:
                 description.append((field,))
 
+        # Return the rows
         if truncate:
             return rows, truncated, tuple(description)
         else:
@@ -102,6 +155,8 @@ class Row(OrderedDict):
     def __getitem__(self, label):
         if type(label) is int:
             return super(OrderedDict, self).__getitem__(list(self.keys())[label])
+        else:
+            return super(OrderedDict, self).__getitem__(label)
 
     def __iter__(self):
         return self.values().__iter__()