Docker 自定 image

首先運行一個alpine:latest的image

docker run -ti alpine:latest

Unable to find image 'alpine:latest' locally
latest: Pulling from library/alpine
aad63a933944: Pull complete
Digest: sha256:b276d875eeed9c7d3f1cfa7edb06b22ed22b14219a7d67c52c56612330348239
Status: Downloaded newer image for alpine:latest
/ #

由於本地沒有alpine:latest, 所以會從Docker hub (opens new window)下載一次到本地

嘗試使用vim ， 可以看到本身是沒有安裝vim

vim

/bin/sh: vim: not found

安裝vim

apk update && apk upgrade
apk add vim

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
(1/5) Installing xxd (8.2.0-r0)
(2/5) Installing lua5.3-libs (5.3.5-r2)
(3/5) Installing ncurses-terminfo-base (6.1_p20200118-r2)
(4/5) Installing ncurses-libs (6.1_p20200118-r2)
(5/5) Installing vim (8.2.0-r0)
Executing busybox-1.31.1-r9.trigger
OK: 35 MiB in 19 packages

現在可以使用vim

如果每次都要自己安裝十分麻煩，所以嘗試自己包裝一個image

建立一個Dockerfile檔案

FROM alpine

RUN apk update && apk upgrade #可忽略
RUN apk add vim

利用Dockerfile生成一個image

docker build -t alpine-with-vim .

Sending build context to Docker daemon   2.56kB
Step 1/3 : FROM alpine:latest
 ---> a187dde48cd2
Step 2/3 : RUN apk update && apk upgrade
 ---> Running in ce4b795adc2a
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
v3.11.5-41-g3deb517cec [http://dl-cdn.alpinelinux.org/alpine/v3.11/main]
v3.11.5-39-g0b5b5381b3 [http://dl-cdn.alpinelinux.org/alpine/v3.11/community]
OK: 11268 distinct packages available
Upgrading critical system libraries and apk-tools:
(1/1) Upgrading apk-tools (2.10.4-r3 -> 2.10.5-r0)
Executing busybox-1.31.1-r9.trigger
Continuing the upgrade transaction with new apk-tools:
OK: 6 MiB in 14 packages
Removing intermediate container ce4b795adc2a
 ---> 01320e1cb037
Step 3/3 : RUN apk add vim
 ---> Running in 3045082b61d6
(1/5) Installing xxd (8.2.0-r0)
(2/5) Installing lua5.3-libs (5.3.5-r2)
(3/5) Installing ncurses-terminfo-base (6.1_p20200118-r2)
(4/5) Installing ncurses-libs (6.1_p20200118-r2)
(5/5) Installing vim (8.2.0-r0)
Executing busybox-1.31.1-r9.trigger
OK: 35 MiB in 19 packages
Removing intermediate container 3045082b61d6
 ---> 9c385d05c3a2
Successfully built 9c385d05c3a2
Successfully tagged alpine-with-vim:latest

可以看到在生成image時已經按照Dockerfile安裝vim

現在有兩個image, 分別是原來的alpine和修改過的alpine-with-vim

docker image ls

REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
alpine-with-vim     latest              9c385d05c3a2        4 minutes ago       34.1MB
alpine              latest              a187dde48cd2        2 weeks ago         5.6MB

運行修改過的alpine-with-vim image

docker run -ti alpine-with-vim /bin/sh

/ #

嘗試運行vim

vim