69 lines
2.3 KiB
Markdown
69 lines
2.3 KiB
Markdown
This is a starting point for Rust solutions to the
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["Build Your Own Docker" Challenge](https://codecrafters.io/challenges/docker).
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In this challenge, you'll build a program that can pull an image from
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[Docker Hub](https://hub.docker.com/) and execute commands in it. Along the way,
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we'll learn about [chroot](https://en.wikipedia.org/wiki/Chroot),
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[kernel namespaces](https://en.wikipedia.org/wiki/Linux_namespaces), the
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[docker registry API](https://docs.docker.com/registry/spec/api/) and much more.
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**Note**: If you're viewing this repo on GitHub, head over to
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[codecrafters.io](https://codecrafters.io) to signup for early access.
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# Usage
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1. Ensure you have [Docker](https://www.docker.com/) installed locally.
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1. Follow the details below ("Running your program locally") to run your Docker
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implementation, which is implemented in `src/main.rs`.
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1. Commit your changes and run `git push origin master` to submit your solution
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to CodeCrafters. Test output will be streamed to your terminal.
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# Running your program locally
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Since you'll need to use linux-specific syscalls in this challenge, we'll run
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your code _inside_ a docker container.
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```sh
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docker build -t my_docker . && docker run --cap-add="SYS_ADMIN" my_docker run some_image /usr/local/bin/docker-explorer echo hey
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```
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(The `--cap-add="SYS_ADMIN"` flag is required to create
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[PID Namespaces](https://man7.org/linux/man-pages/man7/pid_namespaces.7.html))
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To make this easier to type out, you could add a
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[shell alias](https://shapeshed.com/unix-alias/):
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```sh
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alias mydocker='docker build -t mydocker . && docker run --cap-add="SYS_ADMIN" mydocker'
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```
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You can then execute your program like this:
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```sh
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mydocker run ubuntu:latest /usr/local/bin/docker-explorer echo hey
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```
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This command compiles your Rust project, so it might be slow the first time you
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run it. Subsequent runs will be fast.
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# Passing the first stage
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CodeCrafters runs tests when you do a `git push`. Make an empty commit and push
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your solution to see the first stage fail.
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```sh
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git commit --allow-empty -m "Running tests"
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git push origin master
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```
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Go to `src/main.rs` and uncomment the implementation. Commit and push your
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changes to pass the first stage:
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```sh
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git add .
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git commit -m "pass the first stage"
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git push origin master
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```
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Time to move on to the next stage!
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