image2df是什么

image2df是通过图像生成Dockerfile的工具。

这个工具是非常有用的，当你只有docker镜像，需要生成一个Dockerfile。

它是如何工作的

根据图像的历史信息进行反向解析。

如何使用这个图像

# Command alias
echo "alias image2df='docker run -v /var/run/docker.sock:/var/run/docker.sock --rm cucker/image2df'" >> ~/.bashrc
. ~/.bashrc

# Excute command
image2df <IMAGE>

See help docker run --rm cucker/image2df --help For example $ echo "alias image2df='docker run -v /var/run/docker.sock:/var/run/docker.sock --rm cucker/image2df'" >> ~/.bashrc $ . ~/.bashrc $ docker pull mysql $ image2df mysql ========== Dockerfile ========== FROM mysql:latest RUN groupadd -r mysql && useradd -r -g mysql mysql RUN apt-get update && apt-get install -y --no-install-recommends gnupg dirmngr && rm -rf /var/lib/apt/lists/* ENV GOSU_VERSION=1.12 RUN set -eux; \ savedAptMark="$(apt-mark showmanual)"; \ apt-get update; \ apt-get install -y --no-install-recommends ca-certificates wget; \ rm -rf /var/lib/apt/lists/*; \ dpkgArch="$(dpkg --print-architecture | awk -F- '{ print $NF }')"; \ wget -O /usr/local/bin/gosu "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$dpkgArch"; \ wget -O /usr/local/bin/gosu.asc "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$dpkgArch.asc"; \ export GNUPGHOME="$(mktemp -d)"; \ gpg --batch --keyserver hkps://keys.openpgp.org --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4; \ gpg --batch --verify /usr/local/bin/gosu.asc /usr/local/bin/gosu; \ gpgconf --kill all; \ rm -rf "$GNUPGHOME" /usr/local/bin/gosu.asc; \ apt-mark auto '.*' > /dev/null; \ [ -z "$savedAptMark" ] || apt-mark manual $savedAptMark > /dev/null; \ apt-get purge -y --auto-remove -o APT::AutoRemove::RecommendsImportant=false; \ chmod +x /usr/local/bin/gosu; \ gosu --version; \ gosu nobody true RUN mkdir /docker-entrypoint-initdb.d RUN apt-get update && apt-get install -y --no-install-recommends \ pwgen \ openssl \ perl \ xz-utils \ && rm -rf /var/lib/apt/lists/* RUN set -ex; \ key='A4A9406876FCBD3C456770C88C718D3B5072E1F5'; \ export GNUPGHOME="$(mktemp -d)"; \ gpg --batch --keyserver ha.pool.sks-keyservers.net --recv-keys "$key"; \ gpg --batch --export "$key" > /etc/apt/trusted.gpg.d/mysql.gpg; \ gpgconf --kill all; \ rm -rf "$GNUPGHOME"; \ apt-key list > /dev/null ENV MYSQL_MAJOR=8.0 ENV MYSQL_VERSION=8.0.24-1debian10 RUN echo 'deb http://repo.mysql.com/apt/debian/ buster mysql-8.0' > /etc/apt/sources.list.d/mysql.list RUN { \ echo mysql-community-server mysql-community-server/data-dir select ''; \ echo mysql-community-server mysql-community-server/root-pass password ''; \ echo mysql-community-server mysql-community-server/re-root-pass password ''; \ echo mysql-community-server mysql-community-server/remove-test-db select false; \ } | debconf-set-selections \ && apt-get update \ && apt-get install -y \ mysql-community-client="${MYSQL_VERSION}" \ mysql-community-server-core="${MYSQL_VERSION}" \ && rm -rf /var/lib/apt/lists/* \ && rm -rf /var/lib/mysql && mkdir -p /var/lib/mysql /var/run/mysqld \ && chown -R mysql:mysql /var/lib/mysql /var/run/mysqld \ && chmod 1777 /var/run/mysqld /var/lib/mysql VOLUME [/var/lib/mysql] COPY dir:2e040acc386ebd23b8571951a51e6cb93647df091bc26159b8c757ef82b3fcda in /etc/mysql/ COPY file:345a22fe55d3e6783a17075612415413487e7dba27fbf1000a67c7870364b739 in /usr/local/bin/ RUN ln -s usr/local/bin/docker-entrypoint.sh /entrypoint.sh # backwards compat ENTRYPOINT ["docker-entrypoint.sh"] EXPOSE 3306 33060 CMD ["mysqld"] reference

要了解如何构建docker映像，请使用 Docker历史记录——no-trunc命令。

您可以从映像构建docker文件，但它不会包含您想要完全理解映像是如何生成的所有内容。合理地，你可以提取的是dockerfile的MAINTAINER、ENV、EXPOSE、VOLUME、WORKDIR、ENTRYPOINT、CMD和ONBUILD部分。

下面的脚本应该为您工作:

#!/bin/bash
docker history --no-trunc "$1" | \
sed -n -e 's,.*/bin/sh -c #(nop) \(MAINTAINER .*[^ ]\) *0 B,\1,p' | \
head -1
docker inspect --format='{{range $e := .Config.Env}}
ENV {{$e}}
{{end}}{{range $e,$v := .Config.ExposedPorts}}
EXPOSE {{$e}}
{{end}}{{range $e,$v := .Config.Volumes}}
VOLUME {{$e}}
{{end}}{{with .Config.User}}USER {{.}}{{end}}
{{with .Config.WorkingDir}}WORKDIR {{.}}{{end}}
{{with .Config.Entrypoint}}ENTRYPOINT {{json .}}{{end}}
{{with .Config.Cmd}}CMD {{json .}}{{end}}
{{with .Config.OnBuild}}ONBUILD {{json .}}{{end}}' "$1"

我使用它作为脚本的一部分，以图像的形式重新构建运行的容器: https://github.com/docbill/docker-scripts/blob/master/docker-rebase

如果您希望能够重新打包图像，Dockerfile主要是有用的。

需要记住的是，docker映像实际上可以是真实或虚拟机的tar备份。我已经用这种方法制作了几个docker映像。甚至构建历史也显示我导入了一个巨大的tar文件作为创建映像的第一步…

image2df是什么

image2df是通过图像生成Dockerfile的工具。

这个工具是非常有用的，当你只有docker镜像，需要生成一个Dockerfile。

它是如何工作的

根据图像的历史信息进行反向解析。

如何使用这个图像

# Command alias
echo "alias image2df='docker run -v /var/run/docker.sock:/var/run/docker.sock --rm cucker/image2df'" >> ~/.bashrc
. ~/.bashrc

# Excute command
image2df <IMAGE>

See help docker run --rm cucker/image2df --help For example $ echo "alias image2df='docker run -v /var/run/docker.sock:/var/run/docker.sock --rm cucker/image2df'" >> ~/.bashrc $ . ~/.bashrc $ docker pull mysql $ image2df mysql ========== Dockerfile ========== FROM mysql:latest RUN groupadd -r mysql && useradd -r -g mysql mysql RUN apt-get update && apt-get install -y --no-install-recommends gnupg dirmngr && rm -rf /var/lib/apt/lists/* ENV GOSU_VERSION=1.12 RUN set -eux; \ savedAptMark="$(apt-mark showmanual)"; \ apt-get update; \ apt-get install -y --no-install-recommends ca-certificates wget; \ rm -rf /var/lib/apt/lists/*; \ dpkgArch="$(dpkg --print-architecture | awk -F- '{ print $NF }')"; \ wget -O /usr/local/bin/gosu "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$dpkgArch"; \ wget -O /usr/local/bin/gosu.asc "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$dpkgArch.asc"; \ export GNUPGHOME="$(mktemp -d)"; \ gpg --batch --keyserver hkps://keys.openpgp.org --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4; \ gpg --batch --verify /usr/local/bin/gosu.asc /usr/local/bin/gosu; \ gpgconf --kill all; \ rm -rf "$GNUPGHOME" /usr/local/bin/gosu.asc; \ apt-mark auto '.*' > /dev/null; \ [ -z "$savedAptMark" ] || apt-mark manual $savedAptMark > /dev/null; \ apt-get purge -y --auto-remove -o APT::AutoRemove::RecommendsImportant=false; \ chmod +x /usr/local/bin/gosu; \ gosu --version; \ gosu nobody true RUN mkdir /docker-entrypoint-initdb.d RUN apt-get update && apt-get install -y --no-install-recommends \ pwgen \ openssl \ perl \ xz-utils \ && rm -rf /var/lib/apt/lists/* RUN set -ex; \ key='A4A9406876FCBD3C456770C88C718D3B5072E1F5'; \ export GNUPGHOME="$(mktemp -d)"; \ gpg --batch --keyserver ha.pool.sks-keyservers.net --recv-keys "$key"; \ gpg --batch --export "$key" > /etc/apt/trusted.gpg.d/mysql.gpg; \ gpgconf --kill all; \ rm -rf "$GNUPGHOME"; \ apt-key list > /dev/null ENV MYSQL_MAJOR=8.0 ENV MYSQL_VERSION=8.0.24-1debian10 RUN echo 'deb http://repo.mysql.com/apt/debian/ buster mysql-8.0' > /etc/apt/sources.list.d/mysql.list RUN { \ echo mysql-community-server mysql-community-server/data-dir select ''; \ echo mysql-community-server mysql-community-server/root-pass password ''; \ echo mysql-community-server mysql-community-server/re-root-pass password ''; \ echo mysql-community-server mysql-community-server/remove-test-db select false; \ } | debconf-set-selections \ && apt-get update \ && apt-get install -y \ mysql-community-client="${MYSQL_VERSION}" \ mysql-community-server-core="${MYSQL_VERSION}" \ && rm -rf /var/lib/apt/lists/* \ && rm -rf /var/lib/mysql && mkdir -p /var/lib/mysql /var/run/mysqld \ && chown -R mysql:mysql /var/lib/mysql /var/run/mysqld \ && chmod 1777 /var/run/mysqld /var/lib/mysql VOLUME [/var/lib/mysql] COPY dir:2e040acc386ebd23b8571951a51e6cb93647df091bc26159b8c757ef82b3fcda in /etc/mysql/ COPY file:345a22fe55d3e6783a17075612415413487e7dba27fbf1000a67c7870364b739 in /usr/local/bin/ RUN ln -s usr/local/bin/docker-entrypoint.sh /entrypoint.sh # backwards compat ENTRYPOINT ["docker-entrypoint.sh"] EXPOSE 3306 33060 CMD ["mysqld"] reference

这是源自@fallino的答案，通过使用docker历史的输出格式选项进行了一些调整和简化。因为macOS和Gnu/Linux有不同的命令行实用程序，所以Mac需要不同的版本。如果你只需要其中一个，你可以只使用那些行。

#!/bin/bash
case "$OSTYPE" in
    linux*)
        docker history --no-trunc --format "{{.CreatedBy}}" $1 | # extract information from layers
        tac                                                    | # reverse the file
        sed 's,^\(|3.*\)\?/bin/\(ba\)\?sh -c,RUN,'             | # change /bin/(ba)?sh calls to RUN
        sed 's,^RUN #(nop) *,,'                                | # remove RUN #(nop) calls for ENV,LABEL...
        sed 's,  *&&  *, \\\n \&\& ,g'                           # pretty print multi command lines following Docker best practices
    ;;
    darwin*)
        docker history --no-trunc --format "{{.CreatedBy}}" $1 | # extract information from layers
        tail -r                                                | # reverse the file
        sed -E 's,^(\|3.*)?/bin/(ba)?sh -c,RUN,'               | # change /bin/(ba)?sh calls to RUN
        sed 's,^RUN #(nop) *,,'                                | # remove RUN #(nop) calls for ENV,LABEL...
        sed $'s,  *&&  *, \\\ \\\n \&\& ,g'                      # pretty print multi command lines following Docker best practices
    ;;
    *)
        echo "unknown OSTYPE: $OSTYPE"
    ;;
esac

在这一点上是不可能的(除非图像的作者显式地包含Dockerfile)。

然而，它绝对是有用的东西!有两件事将有助于获得这个特性。

可信构建(详见docker-dev讨论) 构建过程生成的连续映像中的更详细的元数据。从长远来看，元数据应该指出是哪个构建命令生成了映像，这意味着可以从一系列映像重建Dockerfile。

docker pull chenzj/dfimage

alias dfimage="docker run -v /var/run/docker.sock:/var/run/docker.sock --rm chenzj/dfimage"

dfimage image_id

dfimage命令的输出如下:

$ dfimage 0f1947a021ce

FROM node:8
WORKDIR /usr/src/app

COPY file:e76d2e84545dedbe901b7b7b0c8d2c9733baa07cc821054efec48f623e29218c in ./
RUN /bin/sh -c npm install
COPY dir:a89a4894689a38cbf3895fdc0870878272bb9e09268149a87a6974a274b2184a in .

EXPOSE 8080
CMD ["npm" "start"]