Hai semuanya, di materi kali ini kita akan membahas tentang Include/Exclude Resources yang kita COPY/ADD pada Dockerfile menggunakan .dockerignore seperti berikut:

Before the docker CLI sends the context to the docker daemon, it looks for a file named .dockerignore in the root directory of the context. If this file exists, the CLI modifies the context to exclude files and directories that match patterns in it. This helps to avoid unnecessarily sending large or sensitive files and directories to the daemon and potentially adding them to images using ADD or COPY. The CLI interprets the .dockerignore file as a newline-separated list of patterns similar to git ignore

This file causes the following build behavior:

Rule Behavior
# comment Ignored
*/temp* Exclude files and directories whose names start with temp in any immediate subdirectory of the root. For example, the plain file /somedir/temporary.txt is excluded, as is the directory /somedir/temp.
*/*/temp* Exclude files and directories starting with temp from any subdirectory that is two levels below the root. For example, /somedir/subdir/temporary.txt is excluded.
temp? Exclude files and directories in the root directory whose names are a one-character extension of temp. For example, /tempa and /tempb are excluded.
!README.md except README.md are excluded from the context.

For Example

Buatlah file dalam folder yang sama dengan Dockerfile seperti berikut:

dan buat file bernama .dockerignore seperti berikut isinya:

Kemudian buatlah file lagi sebagai contoh

  1. README.md
  2. Contribution.md
  3. .idea/connection.xml

Jika dijalankan maka hasilnya seperti berikut:

➜ 07-dockerfile  ls
    Directory: C:\Users\dimasm93\Workspaces\youtube\docker\07-dockerfile

Mode                 LastWriteTime         Length Name
----                 -------------         ------ ----
d-----         6/13/2021   2:26 PM                .idea
-a----         6/13/2021   2:26 PM            115 .dockerignore
-a----         6/13/2021   1:52 PM           2092 belajar-docker-07b-copy-resource.tar.gz 
-a----         6/13/2021   2:26 PM             17 Contribution.md
-a----         6/13/2021   2:05 PM            129 Dockerfile
-a----         6/13/2021   2:26 PM             19 README.md

 ➜ 07-dockerfile ✗  docker build -t dimmaryanto93/centos:0.4 .       
[+] Building 0.2s (8/8) FINISHED
 => [internal] load build definition from Dockerfile                                 0.0s 
 => => transferring dockerfile: 164B                                                 0.0s 
 => [internal] load .dockerignore                                                    0.0s 
 => => transferring context: 34B                                                     0.0s 
 => [internal] load metadata for docker.io/library/centos:7                          0.0s 
 => [1/3] FROM docker.io/library/centos:7                                            0.0s 
 => [internal] load build context                                                    0.0s 
 => => transferring context: 287B                                                    0.0s 
 => CACHED [2/3] RUN mkdir -p /usr/share/nginx/html                                  0.0s 
 => [3/3] ADD . /usr/share/nginx/html                                                0.0s 
 => exporting to image                                                               0.0s 
 => => exporting layers                                                              0.0s 
 => => writing image sha256:7109257718d355a5efa27e9d013337a7d41f56493b11b8e9e103ebf  0.0s 
 => => naming to docker.io/dimmaryanto93/centos:0.4                                  0.0s 


➜ 07-dockerfile  docker run --rm -it dimmaryanto93/centos:0.4     
Dockerfile  README.md  belajar-docker-07b-copy-resource.tar.gz

Cleanup

Seperti biasa, setelah kita mencoba praktikan kita bersih-bersih dulu ya. berikut perintahnya: