path: root/Documentation/gitremote-helpers.txt
diff options
authorbrian m. carlson <>2019-10-16 23:45:34 (GMT)
committerJunio C Hamano <>2019-10-17 07:08:22 (GMT)
commit6f1194246a514ba093a11dde73aabe4c0da5526f (patch)
treec77e309f8c9b926709aeb15bc3a13baa08f149e2 /Documentation/gitremote-helpers.txt
parent5fa0f5238b0cd46cfe7f6fa76c3f526ea98148d9 (diff)
remote-curl: pass on atomic capability to remote side
When pushing more than one reference with the --atomic option, the server is supposed to perform a single atomic transaction to update the references, leaving them either all to succeed or all to fail. This works fine when pushing locally or over SSH, but when pushing over HTTP, we fail to pass the atomic capability to the remote side. In fact, we have not reported this capability to any remote helpers during the life of the feature. Now normally, things happen to work nevertheless, since we actually check for most types of failures, such as non-fast-forward updates, on the client side, and just abort the entire attempt. However, if the server side reports a problem, such as the inability to lock a ref, the transaction isn't atomic, because we haven't passed the appropriate capability over and the remote side has no way of knowing that we wanted atomic behavior. Fix this by passing the option from the transport code through to remote helpers, and from the HTTP remote helper down to send-pack. With this change, we can detect if the server side rejects the push and report back appropriately. Note the difference in the messages: the remote side reports "atomic transaction failed", while our own checking rejects pushes with the message "atomic push failed". Document the atomic option in the remote helper documentation, so other implementers can implement it if they like. Signed-off-by: brian m. carlson <> Signed-off-by: Junio C Hamano <>
Diffstat (limited to 'Documentation/gitremote-helpers.txt')
1 files changed, 5 insertions, 0 deletions
diff --git a/Documentation/gitremote-helpers.txt b/Documentation/gitremote-helpers.txt
index 43f80c8..03b3a68 100644
--- a/Documentation/gitremote-helpers.txt
+++ b/Documentation/gitremote-helpers.txt
@@ -505,6 +505,11 @@ set by Git if the remote helper has the 'option' capability.
Indicate that only the objects wanted need to be fetched, not
their dependents.
+'option atomic' {'true'|'false'}::
+ When pushing, request the remote server to update refs in a single atomic
+ transaction. If successful, all refs will be updated, or none will. If the
+ remote side does not support this capability, the push will fail.