96 lines
3.9 KiB
Markdown
96 lines
3.9 KiB
Markdown
# container-logs
|
|
|
|
[](https://drone.cryptic.systems/volker.raschek/container-logs)
|
|
[](https://pkg.go.dev/git.cryptic.systems/volker.raschek/container-logs)
|
|
|
|
container-log is a utility program. It writes the logs from docker container to
|
|
stdout. The containers can be specified by ame or ID like the `docker logs`
|
|
command. In addition, `container-logs` offers the possibility to search for
|
|
containers by their labels.
|
|
|
|
## Usage
|
|
|
|
The following chapter contains examples how to use `container-logs`.
|
|
|
|
All examples are about an nginx and oracle container. The nginx container has
|
|
the name `nginx` and the id `59a6358197ef`. The oracle container has the name
|
|
`oracle` and the id `9d0bb88fa6a1`
|
|
|
|
### Logs without any restrictions
|
|
|
|
When container-logs is run without restriction, the logs that write the
|
|
containers to stdout and stderr are printed on standard system output.
|
|
|
|
```bash
|
|
$ container-logs
|
|
[0.000] 127.0.0.1 - - [20/Nov/2020:18:57:16 +0000] "HEAD /index.html HTTP/1.1" 200 0 "-" "curl/7.29.0" "-"
|
|
[0.000] 127.0.0.1 - - [20/Nov/2020:18:57:56 +0000] "HEAD /index.html HTTP/1.1" 200 0 "-" "curl/7.29.0" "-"
|
|
[0.000] 127.0.0.1 - - [20/Nov/2020:18:58:37 +0000] "HEAD /index.html HTTP/1.1" 200 0 "-" "curl/7.29.0" "-"
|
|
...
|
|
SQL*Plus: Release 11.2.0.2.0 Production on Fri Nov 20 14:56:25 2020
|
|
Copyright (c) 1982, 2011, Oracle. All rights reserved.
|
|
Connected to:
|
|
Oracle Database 11g Express Edition Release 11.2.0.2.0 - 64bit Production
|
|
```
|
|
|
|
### Logs by container name
|
|
|
|
Containers whose logs write to standard output and standard error output can
|
|
also be selected by name.
|
|
|
|
In the following example only the logs of the container nginx are output. The
|
|
container is selected by its name.
|
|
|
|
```bash
|
|
$ container-logs --name nginx
|
|
[0.000] 127.0.0.1 - - [20/Nov/2020:18:57:16 +0000] "HEAD /index.html HTTP/1.1" 200 0 "-" "curl/7.29.0" "-"
|
|
[0.000] 127.0.0.1 - - [20/Nov/2020:18:57:56 +0000] "HEAD /index.html HTTP/1.1" 200 0 "-" "curl/7.29.0" "-"
|
|
[0.000] 127.0.0.1 - - [20/Nov/2020:18:58:37 +0000] "HEAD /index.html HTTP/1.1" 200 0 "-" "curl/7.29.0" "-"
|
|
...
|
|
```
|
|
|
|
The flag `--n, --name` can be used multiple times to select multiple containers.
|
|
|
|
### Logs by container id
|
|
|
|
The behaviour of `-i, --id` is similar to `-n, --name`. It can be specified
|
|
multiple times. It selects the container by thir ID instead of their name. The
|
|
ID does not need to be specified by their full length. The first characters of
|
|
the ID are sufficient.
|
|
|
|
For example to select the container oracle.
|
|
|
|
```bash
|
|
$ container-logs --id 9d0bb88fa6a1
|
|
[0.000] 127.0.0.1 - - [20/Nov/2020:18:57:16 +0000] "HEAD /index.html HTTP/1.1" 200 0 "-" "curl/7.29.0" "-"
|
|
[0.000] 127.0.0.1 - - [20/Nov/2020:18:57:56 +0000] "HEAD /index.html HTTP/1.1" 200 0 "-" "curl/7.29.0" "-"
|
|
[0.000] 127.0.0.1 - - [20/Nov/2020:18:58:37 +0000] "HEAD /index.html HTTP/1.1" 200 0 "-" "curl/7.29.0" "-"
|
|
```
|
|
|
|
### Logs by container labels
|
|
|
|
Outputting the logs of containers, selected by their labels, is the real reason
|
|
for implementing this little program. Containers are only selected if all
|
|
labels, which were passed, are also defined in the container image.
|
|
|
|
In the following example the container nginx is selected by one of its labels.
|
|
|
|
```bash
|
|
$ container-logs --label "maintainer=NGINX Docker Maintainers <docker-maint@nginx.com>"
|
|
[0.000] 127.0.0.1 - - [20/Nov/2020:18:57:16 +0000] "HEAD /index.html HTTP/1.1" 200 0 "-" "curl/7.29.0" "-"
|
|
[0.000] 127.0.0.1 - - [20/Nov/2020:18:57:56 +0000] "HEAD /index.html HTTP/1.1" 200 0 "-" "curl/7.29.0" "-"
|
|
[0.000] 127.0.0.1 - - [20/Nov/2020:18:58:37 +0000] "HEAD /index.html HTTP/1.1" 200 0 "-" "curl/7.29.0" "-"
|
|
```
|
|
|
|
To find the labels of a container, you can use the inspect sub-command of
|
|
docker. Here is an example:
|
|
|
|
```bash
|
|
$ docker inspect nginx:alpine
|
|
...
|
|
"Labels": {
|
|
"maintainer": "NGINX Docker Maintainers <docker-maint@nginx.com>"
|
|
},
|
|
...
|
|
```
|