Add an "accept_hostkey" parameter to the git module to help automatically

accept hostkeys for git repos and prevent task hangs when the key is unknown

lib/ansible/module_utils/known_hosts.py

+def add_git_host_key(module, url, accept_hostkey=True):
+
+    """ idempotently add a git url hostkey """
+
+    if accept_hostkey:
+
+        fqdn = get_fqdn(module.params['repo'])
+
+        if fqdn:
+            known_host = check_hostkey(module, fqdn)
+            if not known_host:
+                rc, out, err = add_host_key(module, fqdn)
+                if rc != 0:
+                    module.fail_json(msg="failed to add %s hostkey: %s" % (fqdn, out + err))
+
+def get_fqdn(repo_url):
+
+    """ chop the hostname out of a giturl """
+
+    result = None
+    if "@" in repo_url:
+        repo_url = repo_url.split("@", 1)[1]
+        if ":" in repo_url:
+            repo_url = repo_url.split(":")[0]
+            result = repo_url
+        elif "/" in repo_url:
+            repo_url = repo_url.split("/")[0]
+            result = repo_url
+
+    return result
+
+
+def check_hostkey(module, fqdn):
+
+    """ use ssh-keygen to check if key is known """
+
+    result = False
+    keygen_cmd = module.get_bin_path('ssh-keygen', True)
+    this_cmd = keygen_cmd + " -H -F " + fqdn
+    rc, out, err = module.run_command(this_cmd)
+
+    if rc == 0:
+        if out != "":
+            result = True
+
+    return result
+
+def add_host_key(module, fqdn, key_type="rsa"):
+
+    """ use ssh-keyscan to add the hostkey """
+
+    result = False
+    keyscan_cmd = module.get_bin_path('ssh-keyscan', True)
+    this_cmd = "%s -t %s %s >> ~/.ssh/known_hosts" % (keyscan_cmd, key_type, fqdn)
+    rc, out, err = module.run_command(this_cmd)
+
+    return rc, out, err
+

library/source_control/git

@@ -43,6 +43,12 @@ options:
             - What version of the repository to check out.  This can be the
               full 40-character I(SHA-1) hash, the literal string C(HEAD), a
               branch name, or a tag name.
+    accept_hostkey:
+        required: false
+        default: true
+        version_added: "1.5"
+        description:
+            - Add the hostkey for the repo url if not already added.
     reference:
         required: false
         default: null
@@ -118,6 +124,7 @@ EXAMPLES = '''
 import re
 import tempfile
 
+
 def get_version(git_path, dest, ref="HEAD"):
     ''' samples the version of the git repo '''
     os.chdir(dest)
@@ -352,6 +359,7 @@ def main():
             force=dict(default='yes', type='bool'),
             depth=dict(default=None, type='int'),
             update=dict(default='yes', type='bool'),
+            accept_hostkey=dict(default='yes', type='bool'),
             executable=dict(default=None),
             bare=dict(default='no', type='bool'),
         ),
@@ -369,6 +377,10 @@ def main():
     reference = module.params['reference']
     git_path  = module.params['executable'] or module.get_bin_path('git', True)
 
+    # add the git repo's hostkey 
+    if module.params['accept_hostkey']:
+        add_git_host_key(module, repo, accept_hostkey=True)
+
     if bare:
         gitconfig = os.path.join(dest, 'config')
     else:
@@ -430,4 +442,6 @@ def main():
 
 # import module snippets
 from ansible.module_utils.basic import *
+from ansible.module_utils.known_hosts import *
+
 main()