abstract the project filter logic a bit

aeromancer/cli/grep.py

@@ -4,6 +4,7 @@ import logging
 import os
 
 from aeromancer import project
+from aeromancer import project_filter
 
 from cliff.command import Command
 
@@ -15,13 +16,7 @@ class Grep(Command):
 
     def get_parser(self, prog_name):
         parser = super(Grep, self).get_parser(prog_name)
-        parser.add_argument(
+        project_filter.ProjectFilter.add_arguments(parser)
-            '--project',
-            action='append',
-            default=[],
-            dest='projects',
-            help='projects to limit search',
-        )
         parser.add_argument('pattern',
                             action='store',
                             help='regular expression',
@@ -31,7 +26,8 @@ class Grep(Command):
     def take_action(self, parsed_args):
         session = self.app.get_db_session()
         pm = project.ProjectManager(session)
-        for r in pm.grep(parsed_args.pattern, parsed_args.projects):
+        prj_filt = project_filter.ProjectFilter.from_parsed_args(parsed_args)
+        for r in pm.grep(parsed_args.pattern, prj_filt):
             line_num, content, filename, project_name = r
             print('%s/%s:%s:%s' %
                   (project_name, filename, line_num, content.rstrip())

aeromancer/project.py

@@ -194,7 +194,7 @@ class ProjectManager(object):
                 self._remove_file_data(obj, reason='file no longer exists')
                 self.session.flush()
 
-    def grep(self, pattern, projects=[]):
+    def grep(self, pattern, prj_filter):
         """Given a pattern, search for lines in files in all projects that match it.
 
         Returns results of the query, including the four columns line
@@ -210,9 +210,7 @@ class ProjectManager(object):
         ).join(File, Project).filter(
             Line.content.op('regexp')(pattern)
         )
-        if projects:
+        if prj_filter:
-            query = query.filter(
+            query = prj_filter.update_query(query)
-                Project.name.in_(projects)
-            )
         query = query.order_by(Project.name, File.name, Line.number)
         return query.yield_per(20).all()

aeromancer/project_filter.py

@@ -0,0 +1,36 @@
+import argparse
+
+
+from aeromancer.db.models import Project
+
+
+class ProjectFilter(object):
+    """Manage the arguments for filtering queries by project.
+    """
+
+    @staticmethod
+    def add_arguments(parser):
+        """Given an argparse.ArgumentParser add arguments.
+        """
+        grp = parser.add_argument_group('Project Filter')
+        grp.add_argument(
+            '--project',
+            action='append',
+            default=[],
+            dest='projects',
+            help='projects to limit search, by exact name',
+        )
+
+    @classmethod
+    def from_parsed_args(cls, parsed_args):
+        return cls(projects=parsed_args.projects)
+
+    def __init__(self, projects):
+        self.projects = projects
+
+    def update_query(self, query):
+        if self.projects:
+            query = query.filter(
+                Project.name.in_(self.projects)
+            )
+        return query