How to install PHP composer inside a docker container

To install PHP Composer inside a Docker container, you will need to do the following:

  1. Start by creating a new Dockerfile. This file will be used to build an image for your container. In the Dockerfile, include the following lines:
FROM php:7.4-cli
RUN apt-get update && apt-get install -y \
    zip \
RUN curl -sS | php -- --install-dir=/usr/local/bin --filename=composer

This will use the php:7.4-cli image as the base for your container and install the necessary dependencies for Composer (zip and unzip). It will then use curl to download the Composer installer and run it to install Composer in the /usr/local/bin directory.

  1. Next, build the image using the Dockerfile:
docker build -t composer .

This will create an image called composer based on the instructions in the Dockerfile.

  1. Run a new container using the image you just created:
docker run -it --name my-composer composer

This will create a new container called my-composer and start it in interactive mode. You should now be able to use Composer inside the container by running composer followed by the desired command.

For example, to install a package using Composer, you can run:

composer require vendor/package

I hope this helps! Let me know if you have any questions.