Copy File To Docker Container

Then pressing ENTER to use the suggested command:

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Using docker cp to copy files to docker containers

Copying individual files

To copy a file to a container, you can either use its relative or absolute path, and specify the destination directory as follows:

Alternatively, you can copy and rename at the same time, by providing the full destination path:

Note that it is not possible to copy multiple files at once using the docker cp command, unless you either use a for loop:

Or copy the entire directory that contains them (if located in the same directory).

Copying entire directories recursively

When copying a directory, the docker cp command will behave like the Unix cp -a command, which means that the directory will be copied recursively with permission preserved if possible.

Copying absolute and relative paths, such as a parent directory

The docker cp assumes container paths are relative to the container's root directory (i.e. /). A destination path can therefore be written with or without the initial forward slash, as docker cp will see these two commands as identical:

Source paths on the other hand, can be written either in their relative form:

Or in their absolute form:

You can learn more about the docker cp command in the official Docker documentation.

Copying files at build-time using a Dockerfile

A Dockerfile is a text file that contains all the necessary instructions for building a Docker image. These instructions can be used for installing and configuring command line tools, declaring environment variables, exposing ports, copying files from the local environment, and so on.

To copy files and directory at build-time, you can use the COPY instruction:

Where:

• src is the path on your local machine of the file(s) you want to copy.
• dest is the path on the container you want to copy the file to.

COPY source path options

Unlike with the docker cp command, the COPY instruction allows you to copy multiple sources at once–which can be files, directories, or both–by separating them with a whitespace character:

These source paths may also contain wildcards:

It is important to note that the paths of the source files and directories will be interpreted as relative to the source of the context of the build, which means that only the files contained in the directory where the Dockerfile is located will be copied.

You can therefore copy the entire directory of the build context using the dot notation:

But you cannot copy files that are outside of the build context of the Dockerfile:

Also note that when copying a directory, only the content of the directory will be copied, but not the directory itself.

For example, the following command will copy the content of the dir directory into the /app directory:

COPY destination path options

The destination path may either be an absolute path:

Or a path relative to the one specified in the WORKDIR instruction:

The WORKDIR instruction is used to set the working directory for instructions such as COPY, ADD, RUN, etc. If the specified directory doesn't exist, it will be automatically created. In Unix, this is the equivalent of the following command: