There has been a lot of discussion (issues 4242 and 5262) about making
`FROM scratch` either a special case or making `FROM` optional, implying
starting from an empty file system.
This patch makes the build command `FROM scratch` special cased from now on
and if used does not pull/set the the initial layer of the build to the ancient
image ID (511136ea..) but instead marks the build as having no base image. The
next command in the dockerfile will create an image with a parent image ID of "".
This means every image ever can now use one fewer layer!
This also makes the image name `scratch` a reserved name by the TagStore. You
will not be able to tag an image with this name from now on. If any users
currently have an image tagged as `scratch`, they will still be able to use that
image, but will not be able to tag a new image with that name.
Goodbye '511136ea3c5a64f264b78b5433614aec563103b4d4702f3ba7d4d2698e22c158',
it was nice knowing you.
Fixes#4242
Docker-DCO-1.1-Signed-off-by: Josh Hawn <josh.hawn@docker.com> (github: jlhawn)
When we use the engine/env object we can run into a situation where
a string is passed in as the value but later on when we json serialize
the name/value pairs, because the string is made up of just numbers
it appears as an integer and not a string - meaning no quotes. This
can cause parsing issues for clients.
I tried to find all spots where we call env.Set() and the type of the
name being set might end up having a value that could look like an int
(like author). In those cases I switched it to use env.SetJson() instead
because that will wrap it in quotes.
One interesting thing to note about the testcase that I modified is that
the escaped quotes should have been there all along and we were incorrectly
letting it thru. If you look at the metadata stored for that resource you
can see the quotes were escaped and we lost them during the serialization
steps because of the env.Set() stuff. The use of env is probably not the
best way to do all of this.
Closes: #9602
Signed-off-by: Doug Davis <dug@us.ibm.com>
