Docker inspect format returns different date format than inspect

[DavidJFelix]

Relevant issues/pull requests:

#11706
#7670

Summary:

The docker inspect command issued with a -f formatting flag will cause times to be displayed in a manner that is inconsistent with the rest of the API.

Expected

Dates returned by docker inspect match dates returned by docker inspect -f identically, including formatting.

Observed

Dates do not match in formatting. One features a non-standard format.

Reproduce by:

1. Issue a docker inspect command on a container
2. Notice that times are delivered in ISO8601
3. Issue a docker inspect -f {.State} to format the output and display an object that has a time in it.
4. Notice that the times are delivered in a NON ISO8601 manner

Environment

• docker version:

Client version: 1.5.0
Client API version: 1.17
Go version (client): go1.4.1
Git commit (client): a8a31ef
OS/Arch (client): linux/amd64
Server version: 1.5.0
Server API version: 1.17
Go version (server): go1.4.1
Git commit (server): a8a31ef

• docker info:

Containers: 26
Images: 82
Storage Driver: aufs
 Root Dir: /var/lib/docker/aufs
 Backing Filesystem: extfs
 Dirs: 134
Execution Driver: native-0.2
Kernel Version: 3.13.0-52-generic
Operating System: Ubuntu 14.04.2 LTS
CPUs: 2
Total Memory: 3.861 GiB
Name: vagrant
ID: N74I:YFQO:4DEY:I2EY:ZWBB:ZB45:UGHD:77SF:NXGS:BFUV:4QUN:B4SN
WARNING: No swap limit support

• uname -a

Linux vagrant 3.13.0-52-generic #86-Ubuntu SMP Mon May 4 04:32:59 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux

[erikthered]

Using docker inspect with no flags yields the following State block:

    "State": {
        "Running": false,
        "Paused": false,
        "Restarting": false,
        "OOMKilled": false,
        "Dead": false,
        "Pid": 0,
        "ExitCode": 137,
        "Error": "",
        "StartedAt": "2015-06-24T19:01:32.816007457Z",
        "FinishedAt": "2015-06-24T19:02:37.026871139Z"
    },

Whereas, docker inspect -f '{{.State.FinishedAt}}' yields:

2015-06-24 19:02:37.026871139 +0000 UTC

Filtering on just .State has the same issue:

{false false false false false 0 137  2015-06-24 19:01:32.816007457 +0000 UTC 2015-06-24 19:02:37.026871139 +0000 UTC}

docker version
Client version: 1.7.0
Client API version: 1.19
Go version (client): go1.4.2
Git commit (client): 0baf609
OS/Arch (client): linux/amd64
Server version: 1.7.0
Server API version: 1.19
Go version (server): go1.4.2
Git commit (server): 0baf609
OS/Arch (server): linux/amd64

docker info
Containers: 2
Images: 32
Storage Driver: aufs
Root Dir: /var/lib/docker/aufs
Backing Filesystem: extfs
Dirs: 36
Dirperm1 Supported: true
Execution Driver: native-0.2
Logging Driver: json-file
Kernel Version: 3.19.0-21-generic
Operating System: Ubuntu 15.04
CPUs: 2
Total Memory: 3.86 GiB
Name: vulcan
ID: UASH:ETSF:KX4E:6YP7:HKBV:7BTN:QFEQ:XNEK:ZIH5:XPQV:YGQH:RPIM
WARNING: No swap limit support

uname -a
Linux vulcan 3.19.0-21-generic #21-Ubuntu SMP Sun Jun 14 18:31:11 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux

[runcom]

This is because of the way the template is rendered with plain go objects.
docker inspect is working fine because it will defaults to json while -f {{.State}} isn't. This can also be checked doing -f {{json .State}} and times are rendered correctly (in the json format) I'll create a PR to fix this maybe

[runcom]

as per my previous comment I think this issue should be closed but feel free to ping me if I'm mistaken and I'll reopen it

[MetalArend]

This bug is still present in Docker 18.03, both in docker inspect as in docker service inspect. Should I open a new report, or can we reopen this one?

[thaJeztah]

Trying on Docker 18.06.1;

Default output;

docker inspect mycontainer

...
"State": {
    "Status": "running",
    "Running": true,
    "Paused": false,
    "Restarting": false,
    "OOMKilled": false,
    "Dead": false,
    "Pid": 14969,
    "ExitCode": 0,
    "Error": "",
    "StartedAt": "2018-09-17T11:35:38.801585592Z",
    "FinishedAt": "0001-01-01T00:00:00Z"
},
...

String presentation

docker inspect -f '{{.State}}' mycontainer
{running true false false false false 14969 0  2018-09-17T11:35:38.801585592Z 0001-01-01T00:00:00Z <nil>}

String presentation (only StartedAt);

docker inspect -f '{{.State.StartedAt}}' mycontainer
2018-09-17T11:35:38.801585592Z

JSON presentation

docker inspect -f '{{json .State}}' mycontainer
{"Status":"running","Running":true,"Paused":false,"Restarting":false,"OOMKilled":false,"Dead":false,"Pid":14969,"ExitCode":0,"Error":"","StartedAt":"2018-09-17T11:35:38.801585592Z","FinishedAt":"0001-01-01T00:00:00Z"}

[nospam2000]

In Docker version 19.03.4, build 9013bf583a there are still some inconsistencies when the timestamp is not stored with UTC ("Z") timezone , but with the explicit "json" prefix this can be solved:

$ docker image inspect -f '{{.Metadata.LastTagTime}}' 91858d4f2d4c
2020-02-20 20:14:14.766460032 +0100 CET

$ docker image inspect -f '{{json .Metadata.LastTagTime}}' 91858d4f2d4c
"2020-02-20T20:14:14.766460032+01:00"

For ".Created" which is stored with "Z" timezone there is no difference besides the quotes:
$ docker image inspect -f '{{json .Created}}' 91858d4f2d4c
"2020-02-20T16:59:24.777091227Z"

$ docker image inspect -f '{{.Created}}' 91858d4f2d4c
2020-02-20T16:59:24.777091227Z

[DavidJFelix]

Honestly, I'd open a new issue for this. This issue is almost 5 years old and has been closed nearly since it opened. The consensus for the initial issue seemed to be use json but what you describe seems to be a different issue.