Adhere to optional git options

Author: smlindauer

src/sasctl/pzmm/gitIntegration.py

@@ -5,13 +5,30 @@
 from uuid import UUID
 from warnings import warn
 import zipfile
-import git
-from git import Repo
 import io
 
 from .._services.model_repository import ModelRepository as mr
 from ..core import RestObj
 
+try:
+    import git
+    from git import Repo
+except ImportError:
+    git = None
+    
+def checkGitStatus():
+    '''Check to see if GitPython has been installed and if a valid git executable 
+    exists on the target system. If one of those two conditions is not met, then 
+    a RunTime error is raised.
+
+    Raises
+    ------
+    RuntimeError
+        Raised if an invalid git setup for git integration is detected.
+    '''
+    if git is None:
+        raise RuntimeError("The 'GitPython' package and a valid git executable is required" + 
+                           " for use of the git integration functions.")
 
 def getZippedModel(model, gPath, project=None):
     """Retrieve a zipped file containing all of the model contents or a specified
@@ -280,6 +297,8 @@ def gitRepoPush(cls, gPath, commitMessage, remote="origin", branch="main"):
         branch : string
             Branch name for the target pull branch from remote, by default 'main'
         """
+        checkGitStatus()
+    
         repo = Repo(gPath)
         repo.git.add(all=True)
         repo.index.commit(commitMessage)
@@ -299,6 +318,8 @@ def gitRepoPull(cls, gPath, remote="origin", branch="main"):
         branch : string
             Branch name for the target pull branch from remote, by default 'main'
         """
+        checkGitStatus()
+    
         repo = git.Git(gPath)
         repo.pull(remote, branch)