Applying mod to nginx image fails

[pagdot]

Applying a mod to the nginx image fails with:

nginx        | [mod-init] Attempting to run Docker Modification Logic
nginx        | [mod-init] Applying pagdot/nginx-reverse-mod files to container
nginx        | tar: invalid magic
nginx        | tar: short read

According to a question on unix stackexchange the tar binary from alpines busybox doesn"t support a necessary feature

[aptalca]

Can you share more info on what the mod is? The dockerfile for it?

[pagdot]

Here are the sources: https://github.com/pagdot/DockerBuild/tree/nginx-reverse-mod

[aptalca]

I'll look into it more in a bit. But with regards to alpine not working, it does work with our mod system as the openssh-server mods listed are alpine based: https://github.com/linuxserver/docker-mods/blob/openssh-server-rsync/root/etc/cont-init.d/99-rsync#L4

[thelamer]

You need to include a tag with the env var DOCKER_MODS so use:

-e DOCKER_MODS=pagdot/nginx-reverse-mod:latest

[pagdot]

@thelamer Of course, else it would't even try to install the mod as shown in the log above

[thelamer]

I didn't just close this without testing it works fine on my end:

docker run --rm -it -e DOCKER_MODS=pagdot/nginx-reverse-mod:latest lsiobase/alpine:3.11 bash
[mod-init] Curl was not found on this system for Docker mods installing
fetch http://dl-cdn.alpinelinux.org/alpine/v3.11/main/x86_64/APKINDEX.tar.gz
fetch http://dl-cdn.alpinelinux.org/alpine/v3.11/community/x86_64/APKINDEX.tar.gz
(1/3) Installing nghttp2-libs (1.40.0-r0)
(2/3) Installing libcurl (7.67.0-r0)
(3/3) Installing curl (7.67.0-r0)
Executing busybox-1.31.1-r9.trigger
OK: 24 MiB in 31 packages
[mod-init] Attempting to run Docker Modification Logic
[mod-init] Applying pagdot/nginx-reverse-mod:latest files to container
[s6-init] making user provided files available at /var/run/s6/etc...exited 0.
[s6-init] ensuring user provided files have correct perms...exited 0.
[fix-attrs.d] applying ownership & permissions fixes...
[fix-attrs.d] done.
[cont-init.d] executing container initialization scripts...
[cont-init.d] 01-envfile: executing... 
[cont-init.d] 01-envfile: exited 0.
[cont-init.d] 10-adduser: executing... 
usermod: no changes

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-------------------------------------
GID/UID
-------------------------------------

User uid:    911
User gid:    911
-------------------------------------

[cont-init.d] 10-adduser: exited 0.
[cont-init.d] 25-config-reverse: executing... 
Creating DH parameters for additional security. This may take a very long time. There will be another message once this process is completed
/var/run/s6/etc/cont-init.d/25-config-reverse: line 16: openssl: command not found
DH parameters successfully created -  bits
[cont-init.d] 25-config-reverse: exited 0.
[cont-init.d] 99-custom-files: executing... 
[custom-init] no custom files found exiting...
[cont-init.d] 99-custom-files: exited 0.
[cont-init.d] done.
[services.d] starting services
[services.d] done.
root@eb2e42baac27:/# ls -l /defaults/
total 36
-rw-rw-r-- 1 root root  3027 Feb 15 16:28 default
-rw-rw-r-- 1 root root  4140 Feb 15 16:28 ldap.conf
-rw-rw-r-- 1 root root  1892 Feb 15 16:28 nginx.conf
drwxr-xr-x 2 root root 12288 Feb 18 21:31 proxy-confs
-rw-rw-r-- 1 root root  1073 Feb 15 16:28 proxy.conf
-rw-rw-r-- 1 root root  1602 Feb 15 16:28 ssl.conf

[pagdot]

I've got it working. I forgot to add a tag to the mod image. Would it be possible to automatically choose "latest" or at least print a warning or an error?

Sample triggering this error:

$ docker run --rm -it -e DOCKER_MODS=pagdot/nginx-reverse-mod lsiobase/alpine:3.11 bash
Unable to find image 'lsiobase/alpine:3.11' locally
3.11: Pulling from lsiobase/alpine
7a6daffa09ba: Pull complete 
faf9ecdaab4b: Pull complete 
e2f177c3a31b: Pull complete 
Digest: sha256:49dcfdc686285ad66614bda40189e9a62cc56972e2eb21cc3ceeedb07ea84550
Status: Downloaded newer image for lsiobase/alpine:3.11
[mod-init] Curl was not found on this system for Docker mods installing
fetch http://dl-cdn.alpinelinux.org/alpine/v3.11/main/x86_64/APKINDEX.tar.gz
fetch http://dl-cdn.alpinelinux.org/alpine/v3.11/community/x86_64/APKINDEX.tar.gz
(1/3) Installing nghttp2-libs (1.40.0-r0)
(2/3) Installing libcurl (7.67.0-r0)
(3/3) Installing curl (7.67.0-r0)
Executing busybox-1.31.1-r9.trigger
OK: 24 MiB in 31 packages
[mod-init] Attempting to run Docker Modification Logic
[mod-init] Applying pagdot/nginx-reverse-mod files to container
tar: invalid magic
tar: short read
[s6-init] making user provided files available at /var/run/s6/etc...exited 0.
[s6-init] ensuring user provided files have correct perms...exited 0.
[fix-attrs.d] applying ownership & permissions fixes...
[fix-attrs.d] done.