Added in uninstall command.

src/watson/admin.py

@@ -15,15 +15,17 @@ class WatsonSearchChangeList(ChangeList):
     
     def __init__(self, request, model, list_display, list_display_links, list_filter, date_hierarchy, search_fields, list_select_related, list_per_page, list_editable, model_admin):
         """Initializes the search engine."""
-        # Clear the search fields.
-        search_fields = ()
-        # Initialize the change list.
         super(WatsonSearchChangeList, self).__init__(request, model, list_display, list_display_links, list_filter, date_hierarchy, search_fields, list_select_related, list_per_page, list_editable, model_admin)
         
     def get_query_set(self):
         """Creates the query set."""
         # Do the basic searching.
-        qs = super(WatsonSearchChangeList, self).get_query_set()
+        search_fields = self.search_fields
+        self.search_fields = ()
+        try:
+            qs = super(WatsonSearchChangeList, self).get_query_set()
+        finally:
+            self.search_fields = search_fields
         # Do the full text searching.
         if self.query.strip():
             qs = self.model_admin.search_engine.filter(qs, self.query, ranking=False)

src/watson/backends.py

@@ -22,8 +22,12 @@ class SearchBackend(object):
 
     """Base class for all search backends."""
     
+    def is_installed(self):
+        """Checks whether django-watson is installed."""
+        return True
+    
     def do_install(self):
-        """Generates the SQL needed to install django-watson."""
+        """Executes the SQL needed to install django-watson."""
         pass
     
     supports_ranking = False
@@ -73,8 +77,17 @@ class PostgresSearchBackend(SearchBackend):
 
     """A search backend that uses native PostgreSQL full text indices."""
     
+    def is_installed(self):
+        """Checks whether django-watson is installed."""
+        cursor = connection.cursor()
+        cursor.execute("""        
+            SELECT attname FROM pg_attribute
+            WHERE attrelid = (SELECT oid FROM pg_class WHERE relname = 'watson_searchentry') AND attname = 'search_tsv';
+        """)
+        return bool(cursor.fetchall())
+    
     def do_install(self):
-        """Generates the PostgreSQL specific SQL code to install django-watson."""
+        """Executes the PostgreSQL specific SQL code to install django-watson."""
         connection.cursor().execute("""
             -- Ensure that plpgsql is installed.
             CREATE OR REPLACE FUNCTION make_plpgsql() RETURNS VOID LANGUAGE SQL AS
@@ -109,6 +122,16 @@ class PostgresSearchBackend(SearchBackend):
             CREATE TRIGGER watson_searchentry_trigger BEFORE INSERT OR UPDATE
             ON watson_searchentry FOR EACH ROW EXECUTE PROCEDURE watson_searchentry_trigger_handler();
         """)
+        
+    def do_uninstall(self):
+        """Executes the PostgreSQL specific SQL code to uninstall django-watson."""
+        connection.cursor().execute("""
+            ALTER TABLE watson_searchentry DROP COLUMN search_tsv;
+            
+            DROP TRIGGER watson_searchentry_trigger ON watson_searchentry;
+            
+            DROP FUNCTION watson_searchentry_trigger_handler();
+        """)
     
     supports_ranking = True
         

src/watson/management/commands/installwatson.py

@@ -15,4 +15,10 @@ class Command(NoArgsCommand):
         """Runs the management command."""
         verbosity = int(options.get("verbosity", 1))
         backend = get_backend()
-        install_sql = backend.do_install()
+        if backend.is_installed():
+            if verbosity >= 2:
+                self.stdout.write("django-watson is already installed.\n")
+        else:
+            backend.do_install()
+            if verbosity >= 2:
+                self.stdout.write("django-watson has been successfully installed.\n")

src/watson/management/commands/uninstallwatson.py

@@ -0,0 +1,24 @@
+"""Destroys the database indices needed by django-watson."""
+
+from django.core.management.base import NoArgsCommand
+from django.db import transaction
+
+from watson.registration import get_backend
+
+
+class Command(NoArgsCommand):
+
+    help = "Destroys the database indices needed by django-watson."
+    
+    @transaction.commit_on_success
+    def handle_noargs(self, **options):
+        """Runs the management command."""
+        verbosity = int(options.get("verbosity", 1))
+        backend = get_backend()
+        if backend.is_installed():
+            backend.do_uninstall()
+            if verbosity >= 2:
+                self.stdout.write("django-watson has been successfully uninstalled.\n")
+        else:
+            if verbosity >= 2:
+                self.stdout.write("django-watson is not installed.\n")

src/watson/migrations/0002_installwatson.py

@@ -16,6 +16,8 @@ class Migration(DataMigration):
 
     def backwards(self, orm):
         "Write your backwards methods here."
+        
+        call_command("uninstallwatson", verbosity=0)
 
 
     models = {

src/watson/tests.py

@@ -15,6 +15,7 @@ from django.conf.urls.defaults import *
 from django.conf import settings
 from django.contrib import admin
 from django.contrib.auth.models import User
+from django.http import HttpResponseNotFound, HttpResponseServerError
 from django import template
 from django.utils import simplejson as json
 
@@ -99,6 +100,9 @@ class SearchTestBase(TestCase):
 
     @watson.update_index()
     def setUp(self):
+        # If migrations are off, then this is needed to get the indices installed. It has to
+        # be called in the setUp() method, but multiple invocations should be safe.
+        call_command("installwatson", verbosity=0)
         # Remove all the current registered models.
         self.registered_models = watson.get_registered_models()
         for model in self.registered_models:
@@ -479,6 +483,14 @@ urlpatterns = patterns("",
 )
 
 
+def handler404(request):
+    return HttpResponseNotFound("Not found")
+    
+    
+def handler500(request):
+    return HttpResponseServerError("Server error")
+
+
 class AdminIntegrationTest(SearchTestBase):
 
     urls = "watson.tests"