From f9fbe8980ff500f6ed8519a0054afffa6e8ff82b Mon Sep 17 00:00:00 2001
From: Alexander Kukushkin <alexander.kukushkin@zalando.de>
Date: Tue, 2 Jun 2015 13:36:36 +0200
Subject: [PATCH 1/3] Implement lsn_to_bytes bytes_to_lsn functions

---
 helpers/utils.py | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/helpers/utils.py b/helpers/utils.py
index 6b26444f..e08dd657 100644
--- a/helpers/utils.py
+++ b/helpers/utils.py
@@ -6,6 +6,32 @@ import time
 received_sigchld = False
 
 
+def lsn_to_bytes(value):
+    """
+    >>> lsn_to_bytes('1/66000060')
+    6006243424
+    >>> lsn_to_bytes('j/66000060')
+    0
+    """
+    try:
+        e = value.split('/')
+        if len(e) == 2 and len(e[0]) > 0 and len(e[1]) > 0:
+            return (int(e[0], 16) << 32) | int(e[1], 16)
+    except ValueError:
+        pass
+    return 0
+
+
+def bytes_to_lsn(value):
+    """
+    >>> bytes_to_lsn(6006243424)
+    '1/66000060'
+    """
+    id = value >> 32
+    off = value & 0xffffffff
+    return '%x/%x' % (id, off)
+
+
 def sigterm_handler(signo, stack_frame):
     sys.exit()
 

From aa1fc315ae9519780237fe0d910a252d38a06f61 Mon Sep 17 00:00:00 2001
From: Alexander Kukushkin <alexander.kukushkin@zalando.de>
Date: Wed, 3 Jun 2015 16:22:05 +0200
Subject: [PATCH 2/3] Process http requests in a threads with ThreadingMixIn

---
 helpers/api.py    | 32 ++++++++++++++++----------------
 tests/test_api.py |  3 +--
 2 files changed, 17 insertions(+), 18 deletions(-)

diff --git a/helpers/api.py b/helpers/api.py
index 53e3f2fb..6f9a626e 100644
--- a/helpers/api.py
+++ b/helpers/api.py
@@ -9,6 +9,7 @@ if sys.hexversion >= 0x03000000:
     from http.server import BaseHTTPRequestHandler, HTTPServer
 else:
     from BaseHTTPServer import BaseHTTPRequestHandler, HTTPServer
+    from SocketServer import ThreadingMixIn
 
 logger = logging.getLogger(__name__)
 
@@ -28,16 +29,14 @@ class RestApiHandler(BaseHTTPRequestHandler):
 
     def get_postgresql_status(self):
         try:
-            cursor = self.server._cursor()
-            cursor.execute("""SELECT to_char(pg_postmaster_start_time(), 'YYYY-MM-DD HH24:MI:SS.MS TZ'),
-                                     pg_is_in_recovery(),
-                                     CASE WHEN pg_is_in_recovery()
-                                          THEN null
-                                          ELSE pg_current_xlog_location() END,
-                                     pg_last_xlog_receive_location(),
-                                     pg_last_xlog_replay_location(),
-                                     pg_is_in_recovery() AND pg_is_xlog_replay_paused()""")
-            row = cursor.fetchone()
+            row = self.server.query("""SELECT to_char(pg_postmaster_start_time(), 'YYYY-MM-DD HH24:MI:SS.MS TZ'),
+                                              pg_is_in_recovery(),
+                                              CASE WHEN pg_is_in_recovery()
+                                                   THEN null
+                                                   ELSE pg_current_xlog_location() END,
+                                              pg_last_xlog_receive_location(),
+                                              pg_last_xlog_replay_location(),
+                                              pg_is_in_recovery() AND pg_is_xlog_replay_paused()""")[0]
             return {
                 'running': True,
                 'postmaster_start_time': row[0],
@@ -54,7 +53,7 @@ class RestApiHandler(BaseHTTPRequestHandler):
             return {'running': self.server.governor.postgresql.is_running()}
 
 
-class RestApiServer(HTTPServer, Thread):
+class RestApiServer(ThreadingMixIn, HTTPServer, Thread):
 
     def __init__(self, governor, config):
         self.connection_string = 'http://{}/governor'.format(config.get('connect_address', None) or config['listen'])
@@ -62,10 +61,11 @@ class RestApiServer(HTTPServer, Thread):
         HTTPServer.__init__(self, (host, int(port)), RestApiHandler)
         Thread.__init__(self, target=self.serve_forever)
         self.governor = governor
-        self._cursor_holder = None
         self.daemon = True
 
-    def _cursor(self):
-        if not self._cursor_holder or self._cursor_holder.closed:
-            self._cursor_holder = self.governor.postgresql.connection().cursor()
-        return self._cursor_holder
+    def query(self, sql, *params):
+        cursor = self.governor.postgresql.connection().cursor()
+        cursor.execute(sql, params)
+        ret = [r for r in cursor]
+        cursor.close()
+        return ret
diff --git a/tests/test_api.py b/tests/test_api.py
index eff848a3..3b906e4b 100644
--- a/tests/test_api.py
+++ b/tests/test_api.py
@@ -44,8 +44,7 @@ class MockRestApiServer(RestApiServer):
     def __init__(self, Handler, path, *args):
         self.governor = MockGovernor()
         if len(args) > 0:
-            self._cursor = args[0]
-        self._cursor_holder = None
+            self.query = args[0]
         Handler(MockRequest(path), ('0.0.0.0', 8080), self)
 
 

From fad2fbeae094803d3f87345a590cab1e5706a534 Mon Sep 17 00:00:00 2001
From: Alexander Kukushkin <alexander.kukushkin@zalando.de>
Date: Wed, 3 Jun 2015 16:39:29 +0200
Subject: [PATCH 3/3] Import ThreadingMixIn for python3

---
 helpers/api.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/helpers/api.py b/helpers/api.py
index 6f9a626e..869acdf3 100644
--- a/helpers/api.py
+++ b/helpers/api.py
@@ -7,6 +7,7 @@ from threading import Thread
 
 if sys.hexversion >= 0x03000000:
     from http.server import BaseHTTPRequestHandler, HTTPServer
+    from socketserver import ThreadingMixIn
 else:
     from BaseHTTPServer import BaseHTTPRequestHandler, HTTPServer
     from SocketServer import ThreadingMixIn