Added pipeline support maintaining backward compatibility.

1 files changed, 90 insertions, 0 deletions

diff --git a/sqlparse/pipeline.py b/sqlparse/pipeline.py
new file mode 100644
index 0000000..167d083
--- /dev/null
+++ b/sqlparse/pipeline.py
@@ -0,0 +1,90 @@
+# Copyright (C) 2011 Jesus Leganes "piranna", piranna@gmail.com
+#
+# This module is part of python-sqlparse and is released under
+# the BSD License: http://www.opensource.org/licenses/bsd-license.php.
+
+from types import GeneratorType
+
+
+class Pipeline(list):
+    """Pipeline to process filters sequentially"""
+
+    def __call__(self, stream):
+        """Run the pipeline
+
+        Return a static (non generator) version of the result
+        """
+
+        # Run the stream over all the filters on the pipeline
+        for filter in self:
+            # Functions and callable objects (objects with '__call__' method)
+            if callable(filter):
+                stream = filter(stream)
+
+            # Normal filters (objects with 'process' method)
+            else:
+                stream = filter.process(None, stream)
+
+        # If last filter return a generator, staticalize it inside a list
+        if isinstance(stream, GeneratorType):
+            return list(stream)
+        return stream
+
+
+if __name__ == '__main__':
+    sql = """-- type: script
+            -- return: integer
+
+            INCLUDE "Direntry.make.sql";
+
+            INSERT INTO directories(inode)
+                            VALUES(:inode)
+            LIMIT 1"""
+
+    sql2 = """SELECT child_entry,asdf AS inode, creation
+              FROM links
+              WHERE parent_dir == :parent_dir AND name == :name
+              LIMIT 1"""
+
+    sql3 = """SELECT
+    0 AS st_dev,
+    0 AS st_uid,
+    0 AS st_gid,
+
+    dir_entries.type         AS st_mode,
+    dir_entries.inode        AS st_ino,
+    COUNT(links.child_entry) AS st_nlink,
+
+    :creation                AS st_ctime,
+    dir_entries.access       AS st_atime,
+    dir_entries.modification AS st_mtime,
+--    :creation                                                AS st_ctime,
+--    CAST(STRFTIME('%s',dir_entries.access)       AS INTEGER) AS st_atime,
+--    CAST(STRFTIME('%s',dir_entries.modification) AS INTEGER) AS st_mtime,
+
+    COALESCE(files.size,0) AS st_size, -- Python-FUSE
+    COALESCE(files.size,0) AS size     -- PyFilesystem
+
+    FROM dir_entries
+        LEFT JOIN files
+            ON dir_entries.inode == files.inode
+        LEFT JOIN links
+            ON dir_entries.inode == links.child_entry
+    
+    WHERE dir_entries.inode == :inode
+    
+    GROUP BY dir_entries.inode
+    LIMIT 1"""
+
+    from filters import ColumnsSelect
+    from lexer import tokenize
+
+    def show(args):
+        for a in args:
+            print repr(a)
+
+    pipe = Pipeline()
+    pipe.append(tokenize)
+    pipe.append(ColumnsSelect())
+
+    show(pipe(sql3))
\ No newline at end of file