docker(3)快速搭建centos7-python3.6環境
前言
當我們在一臺電腦上搭建了python3.6的環境,下次換臺電腦,又得重新搭建一次,設定環境變數等操作。
好不容易安裝好,一會提示pip不是內部或外部命令,一會又提示pip: command not found,想死的心都有了。
搭建環境是真的麻煩,不弄好又不行,從今天開始學好docker,環境問題從此和你說再見
docker search搜尋映象
docker search : 從Docker Hub(https://hub.docker.com)中搜索指定的映象
比如我這裡搜尋一個基於centos7環境安裝的python3.6版本
[root@jkc ~]# docker search python NAME DESCRIPTION STARS OFFICIAL AUTOMATED python Python is an interpreted, interactive, objec… 5776 [OK] django Django is a free web application framework, … 1040 [OK] pypy PyPy is a fast, compliant alternative implem… 262 [OK] nikolaik/python-nodejs Python with Node.js 57 [OK] joyzoursky/python-chromedriver Python with Chromedriver, for running automa… 57 [OK] arm32v7/python Python is an interpreted, interactive, objec… 54 circleci/python Python is an interpreted, interactive, objec… 42 centos/python-35-centos7 Platform for building and running Python 3.5… 39 centos/python-36-centos7 Platform for building and running Python 3.6… 30 hylang Hy is a Lisp dialect that translates express… 29 [OK] arm64v8/python Python is an interpreted, interactive, objec… 24 revolutionsystems/python Optimized Python Images 18 centos/python-27-centos7 Platform for building and running Python 2.7… 17 bitnami/python Bitnami Python Docker Image 10 [OK] publicisworldwide/python-conda Basic Python environments with Conda. 6 [OK] d3fk/python_in_bottle Simple python:alpine completed by Bottle+Req… 5 [OK] dockershelf/python Repository for docker images of Python. Test… 5 [OK] clearlinux/python Python programming interpreted language with… 4 i386/python Python is an interpreted, interactive, objec… 3 centos/python-34-centos7 Platform for building and running Python 3.4… 2 ppc64le/python Python is an interpreted, interactive, objec… 2 amd64/python Python is an interpreted, interactive, objec… 1 s390x/python Python is an interpreted, interactive, objec… 0 ccitest/python CircleCI test images for Python 0 [OK] saagie/python Repo for python jobs 0
- NAME 映象倉庫名稱
- DESCRIPTION 映象描述資訊
- STARS 映象收藏數
- OFFICIAL 是否為docker官方釋出的映象
- AUTOMATED 是否為自動化構建的映象
- 關於自動化構建,可以檢視官方文件:https://docs.docker.com/docker-hub/builds/#how-automated-builds-work
下載pull映象
上面找的想要下載的映象centos/python-36-centos7,接下來下載到自己本地
docker pull centos/python-36-centos7
[root@jkc docker]# docker pull centos/python-36-centos7 Using default tag: latest latest: Pulling from centos/python-36-centos7 75f829a71a1c: Pull complete e2c4942f4189: Pull complete f1498894b11c: Pull complete da56c9694723: Pull complete 07fa76fc639e: Pull complete abab42dfb7f7: Pull complete dd73d54fbd62: Pull complete 25966a5cbd52: Pull complete b947aec7d116: Pull complete Digest: sha256:ac50754646f0d37616515fb30467d8743fb12954260ec36c9ecb5a94499447e0 Status: Downloaded newer image for centos/python-36-centos7:latest docker.io/centos/python-36-centos7:latest [root@jkc docker]#
安裝其他python版本
如果有小夥伴想安裝其他python版本,比如3.7或者3.8,去https://hub.docker.com搜尋即可
點選選中的標籤,進入複製命令即可
docker images
使用docker images檢視本地已經下載好的映象
[root@jkc docker]# docker images REPOSITORY TAG IMAGE ID CREATED SIZE mysql 5.7 ae0658fdbad5 2 months ago 449MB centos/python-36-centos7 latest 602660fa9b4e 4 months ago 650MB [root@jkc docker]#
執行互動式的容器
Docker會在隔離的容器中執行程序。當執行docker run命令時,Docker會啟動一個程序,併為這個程序分配其獨佔的檔案系統、網路資源和以此程序為根程序的程序組。
在容器啟動時,映象可能已經定義了要執行的二進位制檔案、暴露的網路埠等,但是使用者可以通過docker run命令重新定義
最基本的docker run命令的格式如下:
$ sudo docker run [OPTIONS] IMAGE[:TAG] [COMMAND] [ARG...]
比如我這裡要啟動centos7,進入互動模式,通過docker的兩個引數 -i -t,讓docker執行的容器實現"對話"的能力
- t: 在新容器內指定一個偽終端或終端。
- i: 允許你對容器內的標準輸入 (STDIN) 進行互動
docker run -i -t centos/python-36-centos7 /bin/bash
下進入centos終端後,進python互動環境列印"hello",最後用exit退出
[root@jkc docker]# docker run -i -t centos/python-36-centos7 /bin/bash
(app-root) python
Python 3.6.9 (default, Nov 11 2019, 11:24:16)
[GCC 4.8.5 20150623 (Red Hat 4.8.5-39)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> print("hello")
hello
>>> exit()
(app-root)
後臺模式啟動
run加上-i -t是進互動模式,如果不想進互動模式直接執行指令碼,可以直接使用run,比如echo "hello world",螢幕會輸出"hello world"
docker run centos/python-36-centos7 /bin/echo "hello world"
如果不想在前臺執行,一般我們執行環境會選擇掛後臺,加個-d 引數即可
[root@jkc docker]# docker run centos/python-36-centos7 /bin/echo "hello world"
hello world
[root@jkc docker]# docker run -d centos/python-36-centos7 /bin/echo "hello world"
8c7c7449d8596d0d2b7c6d5672ec68d9da73733984232377fb35b30b876faaf5
使用-d後臺執行後,會發現下面多了一長串,這個就是容器的唯一id,可以通過這個id找到容器
docker ps檢視容器
先run下 training/webapp
docker run -d -p 5000:5000 training/webapp python app.py
使用docker ps檢視正在執行的容器
[root@jkc docker]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
a67640969dd9 training/webapp "python app.py" 31 seconds ago Up 31 seconds 0.0.0.0:5000->5000/tcp admiring_mahavira
[root@jkc docker]#
上面的echo "hello world"只是一個很簡單的輸出指令,執行完就關閉了,所以ps查詢正在執行的查不到,可以加個-a引數,顯示所有的容器,包括未執行的
ps 查詢引數相關語法
- -a :顯示所有的容器,包括未執行的。
- -f :根據條件過濾顯示的內容。
- --format :指定返回值的模板檔案。
- -l :顯示最近建立的容器。
- -n :列出最近建立的n個容器。
- --no-trunc :不截斷輸出。
- -q :靜默模式,只顯示容器編號。
- -s :顯示總的檔案大小。
docker ps -a
[root@jkc docker]# docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
a67640969dd9 training/webapp "python app.py" 2 minutes ago Up 2 minutes 0.0.0.0:5000->5000/tcp admiring_mahavira
8c7c7449d859 centos/python-36-centos7 "container-entrypoin…" 4 minutes ago Exited (0) 4 minutes ago nostalgic_mccarthy
9df0d290b4e6 centos/python-36-centos7 "container-entrypoin…" 5 minutes ago Exited (0) 5 minutes ago wonderful_cohen
c01f59e13a3a centos/python-36-centos7 "container-entrypoin…" 5 minutes ago Exited (0) 5 minutes ago wonderful_hamilton
3c2d40166a8f centos/python-36-centos7 "container-entrypoin…" 12 minutes ago Exited (0) 5 minutes ago pedantic_engelbart
713e29359fcd centos/python-36-centos7 "container-entrypoin…" 14 minutes ago Exited (0) 12 minutes ago priceless_allen
29980b073576 mysql:5.7 "docker-entrypoint.s…" 7 weeks ago Exited (0) 2 hours ago jkcmysql
[root@jkc docker]#
這樣就能找到上面的容器id 8c7c7449d859
,不過沒那麼長
docker logs檢視日誌
可以通過容器id去查執行的日誌
docker logs [容器id]
[root@jkc docker]# docker logs 8c7c7449d859
hello world
[root@jkc docker]#
也可以通過容器的名稱去檢視,注意這裡是容器的名稱,不是映象名稱。容器名稱是系統自動分配的,如上面的最後一項NAMES 值hopeful_poincare
[root@jkc docker]# docker logs nostalgic_mccarthy
hello world
-f: 讓 docker logs 像使用 tail -f 一樣來輸出容器內部的標準輸出。
[root@jkc docker]# docker logs -f 8c7c7449d859
hello world
停止容器
可以用ps檢視正在執行的容器
docker ps
[root@jkc docker]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
a67640969dd9 training/webapp "python app.py" 9 minutes ago Up 9 minutes 0.0.0.0:5000->5000/tcp admiring_mahavira
停止容器的話,可以用stop容器的id或者容器NAME名稱
docker stop a67640969dd9
或者提供容器名稱admiring_mahavira來停止
docker stop admiring_mahavira
啟動容器
提供start啟動容器
[root@jkc docker]# docker start a67640969dd9
a67640969dd9
[root@jkc docker]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
a67640969dd9 training/webapp "python app.py" 13 minutes ago Up 6 seconds 0.0.0.0:5000->5000/tcp admiring_mahavira
正在執行的容器,可以使用 docker restart 命令來重啟
[root@jkc docker]# docker restart a67640969dd9
a67640969dd9
刪除容器
使用 docker rm 命令來刪除不需要的容器
[root@jkc docker]# docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
a67640969dd9 training/webapp "python app.py" 14 minutes ago Up About a minute 0.0.0.0:5000->5000/tcp admiring_mahavira
8c7c7449d859 centos/python-36-centos7 "container-entrypoin…" 17 minutes ago Exited (0) 17 minutes ago nostalgic_mccarthy
9df0d290b4e6 centos/python-36-centos7 "container-entrypoin…" 18 minutes ago Exited (0) 18 minutes ago wonderful_cohen
c01f59e13a3a centos/python-36-centos7 "container-entrypoin…" 18 minutes ago Exited (0) 18 minutes ago wonderful_hamilton
3c2d40166a8f centos/python-36-centos7 "container-entrypoin…" 25 minutes ago Exited (0) 18 minutes ago pedantic_engelbart
713e29359fcd centos/python-36-centos7 "container-entrypoin…" 26 minutes ago Exited (0) 25 minutes ago priceless_allen
29980b073576 mysql:5.7 "docker-entrypoint.s…" 7 weeks ago Exited (0) 3 hours ago jkcmysql
[root@jkc docker]# docker rm 8c7c7449d859
8c7c7449d859
[root@jkc docker]# docker rm 9df0d290b4e6
9df0d290b4e6
[root@jkc docker]# docker rm admiring_mahavira
Error response from daemon: You cannot remove a running container a67640969dd99d6f26810857d29dd47a43088ea927c03b36dd04dddaf18a4dcf. Stop the container before attempting removal or force remove
[root@jkc docker]#
但是rm 正在執行的容器時候,它會報錯,需先stop,才能rm
[root@jkc docker]# docker stop admiring_mahavira
admiring_mahavira
[root@jkc docker]# docker rm admiring_mahavira
admiring_mahavira
[root@jkc docker]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
[root@jkc docker]#