From 4b8712eacbc47ac048d63ab7d5619b02b563f2e7 Mon Sep 17 00:00:00 2001 From: Alfred Landrum Date: Mon, 20 Mar 2017 11:38:17 -0700 Subject: [PATCH] Let graphdrivers declare diff stream fidelity This allows graphdrivers to declare that they can reproduce the original diff stream for a layer. If they do so, the layer store will not use tar-split processing, but will still verify the digest on layer export. This makes it easier to experiment with non-default diff formats. Signed-off-by: Alfred Landrum --- docs/extend/plugins_graphdriver.md | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/docs/extend/plugins_graphdriver.md b/docs/extend/plugins_graphdriver.md index 74caa938f8..c134b1ebc4 100644 --- a/docs/extend/plugins_graphdriver.md +++ b/docs/extend/plugins_graphdriver.md @@ -84,6 +84,29 @@ The request also includes a list of UID and GID mappings, structed as follows: Respond with a non-empty string error if an error occurred. +### /GraphDriver.Capabilities + +**Request**: +```json +{} +``` + +Get behavioral characteristics of the graph driver. If a plugin does not handle +this request, the engine will use default values for all capabilities. + +**Response**: +```json +{ + "ReproducesExactDiffs": false, +} +``` + +Respond with values of capabilities: + +* **ReproducesExactDiffs** Defaults to false. Flags that this driver is capable +of reproducing exactly equivalent diffs for read-only filesystem layers. + + ### /GraphDriver.Create **Request**: