Commit Graph

4 Commits

Author SHA1 Message Date
Sebastiaan van Stijn e5702e000c
Tweak validation messages
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
2019-03-19 03:17:02 +01:00
Sebastiaan van Stijn f2424bd375
Fix labels copying value from environment variables
This patch fixes a bug where labels use the same behavior as `--env`, resulting
in a value to be copied from environment variables with the same name as the
label if no value is set (i.e. a simple key, no `=` sign, no value).

An earlier pull request addressed similar cases for `docker run`;
2b17f4c8a8, but this did not address the
same situation for (e.g.) `docker service create`.

Digging in history for this bug, I found that use of the `ValidateEnv`
function for  labels was added in the original implementation of the labels feature in
abb5e9a077 (diff-ae476143d40e21ac0918630f7365ed3cR34)

However, the design never intended it to expand environment variables,
and use of this function was either due to either a "copy/paste" of the
equivalent `--env` flags, or a misunderstanding (the name `ValidateEnv` does
not communicate that it also expands environment variables), and the existing
`ValidateLabel` was designed for _engine_ labels (which required a value to
be set).

Following the initial implementation, other parts of the code followed
the same (incorrect) approach, therefore leading the bug to be introduced
in services as well.

This patch:

- updates the `ValidateLabel` to match the expected validation
  rules (this function is no longer used since 31dc5c0a9a),
  and the daemon has its own implementation)
- corrects various locations in the code where `ValidateEnv` was used instead of `ValidateLabel`.

Before this patch:

```bash
export SOME_ENV_VAR=I_AM_SOME_ENV_VAR
docker service create --label SOME_ENV_VAR --tty --name test busybox

docker service inspect --format '{{json .Spec.Labels}}' test
{"SOME_ENV_VAR":"I_AM_SOME_ENV_VAR"}
```

After this patch:

```bash
export SOME_ENV_VAR=I_AM_SOME_ENV_VAR
docker service create --label SOME_ENV_VAR --tty --name test busybox

docker container inspect --format '{{json .Config.Labels}}' test
{"SOME_ENV_VAR":""}
```

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
2019-03-19 03:01:57 +01:00
Tom Klingenberg 96c026eb30 import environment variables that are present
previously docker did import environment variables if they were present
but created them if they were not when it was asked via a --env-file
cli option to import but not create them.

fix is to only import the variable into the environment if it is present.

additionally do not import variable names of zero-length (which are lines
w/ a potential variable definition w/o a variable name).

refs:

- https://github.com/docker/for-linux/issues/284

Signed-off-by: Tom Klingenberg <tklingenberg@lastflood.net>
2018-07-02 07:37:12 +02:00
Vincent Demeester 2b17f4c8a8
Fix `--label-file` weird behavior
`--label-file` has the exact same behavior as `--env-file`, meaning any
placeholder (i.e. a simple key, no `=` sign, no value), it will get the
value from the environment variable.

For `--label-file` it should just add an empty label.

Signed-off-by: Vincent Demeester <vincent@sbr.pm>
2018-01-29 11:08:54 -08:00