Use enum for process types

Author: ildus

Dockerfile.tmpl

@@ -2,10 +2,10 @@ FROM postgres:${PG_VERSION}-alpine
 
 ENV PYTHON=python${PYTHON_VERSION}
 RUN if [ "${PYTHON_VERSION}" = "2" ] ; then \
-	apk add --no-cache curl python2 python2-dev build-base py-virtualenv py-pip; \
+	apk add --no-cache curl python2 python2-dev build-base musl-dev py-virtualenv py-pip; \
 	fi
 RUN if [ "${PYTHON_VERSION}" = "3" ] ; then \
-	apk add --no-cache curl python3 python3-dev build-base py-virtualenv; \
+	apk add --no-cache curl python3 python3-dev build-base musl-dev py-virtualenv; \
 	fi
 ENV LANG=C.UTF-8
 

testgres/connection.py

@@ -34,7 +34,7 @@ def __init__(self, node, dbname=None, username=None, password=None):
         username = username or default_username()
 
         self._node = node
-        self._backend_pid = 0
+        self._pid = 0
 
         self._connection = pglib.connect(
             database=dbname,
@@ -54,10 +54,10 @@ def connection(self):
         return self._connection
 
     @property
-    def backend_pid(self):
-        if not self._backend_pid:
-            self._backend_pid = self.execute("select pg_backend_pid();")[0][0]
-        return self._backend_pid
+    def pid(self):
+        if not self._pid:
+            self._pid = self.execute("select pg_backend_pid();")[0][0]
+        return self._pid
 
     @property
     def cursor(self):

testgres/enums.py

@@ -35,3 +35,18 @@ def __bool__(self):
 
     # for Python 2.x
     __nonzero__ = __bool__
+
+
+class ProcessType(Enum):
+    """
+    Types of postgres processes
+    """
+    Checkpointer = 'postgres: checkpointer'
+    BackgroundWriter = 'postgres: background writer'
+    WalWriter = 'postgres: walwriter'
+    AutovacuumLauncher = 'postgres: autovacuum launcher'
+    StatsCollector = 'postgres: stats collector'
+    LogicalReplicationLauncher = 'postgres: logical replication launcher'
+    WalReceiver = 'postgres: walreceiver'
+    WalSender = 'postgres: walsender'
+    Startup = 'postgres: startup'

testgres/node.py

@@ -16,7 +16,7 @@
 from six import raise_from
 from tempfile import mkstemp, mkdtemp
 
-from .enums import NodeStatus
+from .enums import NodeStatus, ProcessType
 
 from .cache import cached_initdb
 
@@ -465,25 +465,13 @@ def get_auxiliary_pids(self):
         result = {}
         for child in children:
             line = child.cmdline()[0]
-            if line.startswith('postgres: checkpointer'):
-                result['checkpointer'] = child.pid
-            elif line.startswith('postgres: background writer'):
-                result['bgwriter'] = child.pid
-            elif line.startswith('postgres: walwriter'):
-                result['walwriter'] = child.pid
-            elif line.startswith('postgres: autovacuum launcher'):
-                result['autovacuum_launcher'] = child.pid
-            elif line.startswith('postgres: stats collector'):
-                result['stats'] = child.pid
-            elif line.startswith('postgres: logical replication launcher'):
-                result['logical_replication_launcher'] = child.pid
-            elif line.startswith('postgres: walreceiver'):
-                result['walreceiver'] = child.pid
-            elif line.startswith('postgres: walsender'):
-                result.setdefault('walsenders', [])
-                result['walsenders'].append(child.pid)
-            elif line.startswith('postgres: startup'):
-                result['startup'] = child.pid
+            for ptype in ProcessType:
+                if ptype == ProcessType.WalSender \
+                        and line.startswith(ptype.value):
+                    result.setdefault(ptype, [])
+                    result[ptype].append(child.pid)
+                elif line.startswith(ptype.value):
+                    result[ptype] = child.pid
 
         return result
 

tests/test_simple.py

@@ -40,6 +40,7 @@
 
 from testgres import bound_ports
 from testgres.utils import pg_version_ge
+from testgres.enums import ProcessType
 
 
 def util_exists(util):
@@ -709,28 +710,28 @@ def test_pids(self):
             psutil = None
 
         master_processes = (
-            'checkpointer',
-            'bgwriter',
-            'walwriter',
-            'autovacuum_launcher',
-            'stats',
-            'logical_replication_launcher',
-            'walsenders',
+            ProcessType.Checkpointer,
+            ProcessType.BackgroundWriter,
+            ProcessType.WalWriter,
+            ProcessType.AutovacuumLauncher,
+            ProcessType.StatsCollector,
+            ProcessType.LogicalReplicationLauncher,
+            ProcessType.WalSender,
         )
         repl_processes = (
-            'startup',
-            'checkpointer',
-            'bgwriter',
-            'stats',
-            'walreceiver',
+            ProcessType.Startup,
+            ProcessType.Checkpointer,
+            ProcessType.BackgroundWriter,
+            ProcessType.StatsCollector,
+            ProcessType.WalReceiver,
         )
 
         with get_new_node('master') as master:
             master.init().start()
 
             self.assertIsNotNone(master.pid)
             with master.connect() as con:
-                self.assertTrue(con.backend_pid > 0)
+                self.assertTrue(con.pid > 0)
 
             with master.backup() as backup:
                 with backup.spawn_replica('repl', True) as repl:
@@ -740,14 +741,16 @@ def test_pids(self):
                         self.assertIsNone(repl.auxiliary_pids)
                     else:
                         master_pids = master.auxiliary_pids
-                        for name in master_processes:
-                            self.assertTrue(name in master_pids)
-                        self.assertTrue(len(master_pids['walsenders']) == 1)
+                        for ptype in master_processes:
+                            self.assertIn(ptype, master_pids)
+                        self.assertTrue(len(master_pids[ProcessType.WalSender]) == 1)
 
                         repl_pids = repl.auxiliary_pids
-                        for name in repl_processes:
-                            self.assertTrue(name in repl_pids)
-                        self.assertTrue(repl.get_walsender_pid() == master_pids['walsenders'][0])
+                        for ptype in repl_processes:
+                            self.assertIn(ptype, repl_pids)
+
+                        sender_pid = master_pids[ProcessType.WalSender][0]
+                        self.assertTrue(repl.get_walsender_pid() == sender_pid)
 
 
 if __name__ == '__main__':