Use dataset-connectors 2.0 api (wip)

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

diff --git a/datasette_pytables/__init__.py b/datasette_pytables/__init__.py
index 58fee10364d3fec5c83d5b011579555f8d492712..396cd0dbb93a09dbcd41da70b1d505e6a72d822c 100644 (file)
--- a/datasette_pytables/__init__.py
+++ b/datasette_pytables/__init__.py
@@ -1,8 +1,58 @@
 from moz_sql_parser import parse
 import re
+
 import tables
+import datasette_connectors as dc
+
+
+class PyTablesConnection(dc.Connection):
+    def __init__(self, path, connector):
+        super().__init__(path, connector)
+        self.h5file = tables.open_file(path)
+
+
+class PyTablesConnector(dc.Connector):
+    connector_type = 'pytables'
+    connection_class = PyTablesConnection
+
+    def table_names(self):
+        return [
+            node._v_pathname
+            for node in self.conn.h5file
+            if not(isinstance(node, tables.group.Group))
+        ]
+
+    def table_count(self, table_name):
+        table = self.conn.h5file.get_node(table_name)
+        return int(table.nrows)
+
+    def table_info(self, table_name):
+        table = self.conn.h5file.get_node(table_name)
+        colnames = ['value']
+        if isinstance(table, tables.table.Table):
+            colnames = table.colnames
+
+        return [
+            {
+                'idx': idx,
+                'name': colname,
+                'primary_key': False,
+            }
+            for idx, colname in enumerate(colnames)
+        ]
+
+    def hidden_table_names(self):
+        return []
+
+    def detect_spatialite(self):
+        return False
+
+    def view_names(self):
+        return []
+
+    def detect_fts(self, table_name):
+        return False
 
-_connector_type = 'pytables'
 
 def inspect(path):
     "Open file and return tables info"
@@ -31,7 +81,7 @@ def inspect(path):
 
 def _parse_sql(sql, params):
     # Table name
-    sql = re.sub('(?i)from \[(.*)]', 'from "\g<1>"', sql)
+    sql = re.sub(r'(?i)from \[(.*)]', r'from "\g<1>"', sql)
     # Params
     for param in params:
         sql = sql.replace(":" + param, param)
@@ -43,7 +93,7 @@ def _parse_sql(sql, params):
         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)
+                modified_sql = re.sub('(?i)where (.*)(' + token + ')', r'\g<2>', sql)
                 parsed = parse(modified_sql)
                 parsed['where'] = res.group(1).strip()
                 break
@@ -81,7 +131,7 @@ class Connection:
 
         if parsed_sql['from'] == 'sqlite_master':
             rows = self._execute_datasette_query(sql, params)
-            description = (('value',))
+            description = (('value',),)
             return rows, truncated, description
 
         table = self.h5file.get_node(parsed_sql['from'])
@@ -146,6 +196,16 @@ class Connection:
             else:
                 query = parsed_sql['where']
 
+        # Sort by column
+        orderby = ''
+        if 'orderby' in parsed_sql:
+            orderby = parsed_sql['orderby']
+            if type(orderby) is list:
+                orderby = orderby[0]
+            orderby = orderby['value']
+            if orderby == 'rowid':
+                orderby = ''
+
         # Limit number of rows
         limit = None
         if 'limit' in parsed_sql:
@@ -159,6 +219,8 @@ class Connection:
         # Execute query
         if query:
             table_rows = table.where(query, params, start, end)
+        elif orderby:
+            table_rows = table.itersorted(orderby, start=start, stop=end)
         else:
             table_rows = table.iterrows(start, end)
 
@@ -233,23 +295,23 @@ class Connection:
 
     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:
+        if sql == 'select sql from sqlite_master where name = :n and type=:t':
+            if params['t'] == 'view':
                 return []
+            else:
+                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")
+            raise Exception("SQLite queries cannot be executed with this connector: %s, %s" % (sql, params))
+
 
 class Row(list):
     def __init__(self, values=None):