enum for xlog_method in NodeBackup

Author: Valeria1235

testgres/backup.py

@@ -5,12 +5,12 @@
 import tempfile
 
 from six import raise_from
+from enum import Enum
 
 from .consts import \
     DATA_DIR, \
     PG_CONF_FILE, \
-    BACKUP_LOG_FILE, \
-    DEFAULT_XLOG_METHOD
+    BACKUP_LOG_FILE
 
 from .exceptions import BackupException
 
@@ -20,6 +20,16 @@
     execute_utility
 
 
+class XLogMethod(Enum):
+    """
+    Available WAL methods for NodeBackup
+    """
+
+    none = 'none'
+    fetch = 'fetch'
+    stream = 'stream'
+
+
 class NodeBackup(object):
     """
     Smart object responsible for backups
@@ -33,7 +43,7 @@ def __init__(self,
                  node,
                  base_dir=None,
                  username=None,
-                 xlog_method=DEFAULT_XLOG_METHOD):
+                 xlog_method=XLogMethod.fetch):
         """
         Create a new backup.
 
@@ -47,6 +57,13 @@ def __init__(self,
         if not node.status():
             raise BackupException('Node must be running')
 
+        # Check arguments
+        if not isinstance(xlog_method, XLogMethod):
+            try:
+                xlog_method = XLogMethod(xlog_method)
+            except ValueError:
+                raise BackupException('Invalid xlog_method "{}"'.format(xlog_method))
+
         # Set default arguments
         username = username or default_username()
         base_dir = base_dir or tempfile.mkdtemp()
@@ -68,7 +85,7 @@ def __init__(self,
             "-h", node.host,
             "-U", username,
             "-D", data_dir,
-            "-X", xlog_method
+            "-X", xlog_method.value
         ]
         execute_utility(_params, self.log_file)
 

testgres/consts.py

@@ -12,6 +12,3 @@
 PG_LOG_FILE = "postgresql.log"
 UTILS_LOG_FILE = "utils.log"
 BACKUP_LOG_FILE = "backup.log"
-
-# default argument value
-DEFAULT_XLOG_METHOD = "fetch"

testgres/node.py

@@ -27,8 +27,7 @@
     HBA_CONF_FILE, \
     RECOVERY_CONF_FILE, \
     PG_LOG_FILE, \
-    UTILS_LOG_FILE, \
-    DEFAULT_XLOG_METHOD
+    UTILS_LOG_FILE
 
 from .exceptions import \
     CatchUpException,   \
@@ -52,6 +51,10 @@
     method_decorator, \
     positional_args_hack
 
+from .backup import \
+    XLogMethod,     \
+    NodeBackup
+
 
 class NodeStatus(IntEnum):
     """
@@ -838,7 +841,7 @@ def execute(self,
 
             return res
 
-    def backup(self, username=None, xlog_method=DEFAULT_XLOG_METHOD):
+    def backup(self, username=None, xlog_method=XLogMethod.fetch):
         """
         Perform pg_basebackup.
 
@@ -850,15 +853,14 @@ def backup(self, username=None, xlog_method=DEFAULT_XLOG_METHOD):
             A smart object of type NodeBackup.
         """
 
-        from .backup import NodeBackup
         return NodeBackup(node=self,
                           username=username,
                           xlog_method=xlog_method)
 
     def replicate(self,
                   name=None,
                   username=None,
-                  xlog_method=DEFAULT_XLOG_METHOD,
+                  xlog_method=XLogMethod.fetch,
                   use_logging=False):
         """
         Create a binary replica of this node.