Add git pull with cooldown interval

gitmgr.py

@@ -2,6 +2,7 @@ import git
 import os
 import shutil
 import tempfile
+import time
 
 from util import load_env
 
@@ -12,18 +13,21 @@ class GitManagerConfiguration:
         origin = load_env("GIT_ORIGIN", None)
         wc_path = load_env("GIT_WC_PATH", None)
         git_pw = load_env("GIT_PASSWORD", None)
+        pull_intv = load_env("GIT_PULL_INTV", None)
 
         return GitManagerConfiguration(origin=origin,
                                        git_pw=git_pw,
-                                       wc_path=wc_path)
+                                       wc_path=wc_path,
+                                       pull_intv=pull_intv)
 
-    def __init__(self, origin, git_pw=None, wc_path=None):
+    def __init__(self, origin, git_pw=None, wc_path=None, pull_intv=None):
         if not origin:
             raise ValueError("Git origin cannot be empty!")
 
         self._origin = origin
         self._git_pw = git_pw
         self._wc_path = wc_path
+        self._pull_intv = 30 if pull_intv is None else int(pull_intv)
 
     @property
     def origin(self):
@@ -37,6 +41,10 @@ class GitManagerConfiguration:
     def wc_path(self):
         return self._wc_path
 
+    @property
+    def pull_intv(self):
+        return self._pull_intv
+
 
 class GitManager:
     def __init__(self, configuration):
@@ -45,6 +53,7 @@ class GitManager:
 
         self._configuration = configuration
         self._wc = None
+        self._last_pull = 0
 
     @property
     def configuration(self):
@@ -138,6 +147,7 @@ class GitManager:
     def setup(self):
         self._setup_wc()
         self._init_repo()
+        self.pull(force=True)
 
     def teardown(self):
         self._teardown_wc()
@@ -148,3 +158,31 @@ class GitManager:
         print(f"\tUsing working copy path %s" % self._wc)
         if not self._wc == self.configuration.wc_path:
             print("\tUsing a temporary working copy.")
+
+    @property
+    def head_sha(self):
+        return None if self.repo is None else self.repo.head.object.hexsha
+
+    def pull(self, force=False):
+        """Pull from origin.
+
+        Arguments:
+            `force` -- Do a pull even though the pull interval has not elapsed
+
+        Returns: True if pull was executed
+        """
+
+        if not force and (time.time() - self._last_pull < self.configuration.pull_intv):
+            return False
+
+        self._last_pull = time.time()
+
+        old_head = self.head_sha
+
+        # get the origin
+        # (We verified during initialization that this origin exists.)
+        origin = self.repo.remote('origin')
+
+        origin.pull(rebase=True)
+
+        return self.head_sha != old_head