I need to edit a file in a docker container. as no advanced ide inside the container,I wonder if vscode or some other ide can access into the container and let me edit files as outside the container.
With the May, 2nd 2019 announcement of "Remote Development with VS Code", you actually can use The Remote - Containers extension :
The Remote - Containers extension lets you use a Docker container as a full-featured development environment.
Containers make a great development environment because you can:
Develop with a consistent and easily reproducible toolchain and on the same operating system you are deploying to.
Quickly swap between different, isolated development environments and safely make updates without worrying about impacting your local machine.
Make it easy for new team members / contributors to get up and running in a consistent development environment.
Docker Workspace makes enabled to add folder inside a running docker container.
Docker extension for VS Code (ms-azuretools.vscode-docker) allows you to right-click on any running container in the list, then choose 'Attach Visual Studio Code' - and you will be able to open any folder inside Docker container in a new VS Code window. I presume you must have The Remote - Containers extensions installed as well.
Start the container by mapping the host path with container path using -v
docker run -v ~/yourlocalpath:/dockerpath
Changes you make on this folder will be reflected inside.
Related
for the development of my Python project I have setup a Remote Development Container. The project uses, for example, MariaDB and RabbitMQ. Until recently I built and started containers for those services outside of VSCode. A few days ago, I reworked the project using Docker Compose so that I can manage the other containers using the remarkable Docker extension (Id: ms-azuretools.vscode-docker, Version: 1.22.0). That is working fine, besides one issue I cannot figure out:
I can start all containers using compose up, however, the Python project Remote Development Container is not staying up. Currently, I open the project folder in a second VSCode window and use the "Reopen in Container" command.
However, it would be nice if the Python project container is staying up and I could just use the "Attach Visual Studio Code" command from the Docker extension Containers menu.
I am wondering, if there is something I can add to the .devcontainer.json or some other configuration file to realize this scenario?
Any help is much appreciated!
If it helps I can post the docker-compose.yml, Dockerfile's or the .devcontainer.json, please let me know what is required.
Is it possible to run code someFile.js from inside a docker container, and have it open in VS Code?
Why do I want to do this? Because vue dev tools allows you to open a vue component from within the browser. This is especially helpful for new devs that want to quickly track down components and open them in the editor.
Unfortunatly - since my dev server is running inside a docker container - this functionality doesn't work. This is because the editor is opened from within the devserver.
Might be worth noting, I'm using Visual Studio Code Remote - Containers.
So to narrow the question furthur:
How can I allow launch VS Code from a docker container, so that vue dev tools can open that file in my local editor?
Yes, if you don't mind running your vue tools inside the docker container as well. You have to set up a .devcontainer.json file specifying the dockerfile or image or dockercompose file to use to build the container. It will create the container for you and automatically mount your project directory by default, but there are a lot of alternative configuration options as well.
This means you'd open VS Code and basically your whole IDE would be in the docker container. You could call vue tools from the VS Code terminal, including calls to code.
I've been doing this with some tensorflow stuff for the last 6 weeks or so. It was a little confusing at first, but now I really like it.
One challenge I've encountered so far is that if you are deploying your image as a deliverable, using a container as a dev environment can cause some dev tool creep into the image (like including dev tools in your Dockerfile that you need in development but dont want in the deployed image). There are probably good ways to deal with this but I haven't explored them all yet.
Another note: I can't seem to find the docs, but I think the recommended way is to use WSL2-backed docker, and then do all your docker mounting and docker client invocations from the WSL2 filesystem to docker instead of from Windows to Docker. I guess if WSL2 and docker are sharing the same VM, the mounted file systems are faster between WSL2/Docker than from Windows/Docker. This has worked well for me so far...
I've managed to adapt this dockerized version of VS Code to our restrictive runtime environment (Openshift), although it does assume connection to the internet, so extensions and Intellisense ML model had to be preinstalled:
https://hub.docker.com/r/codercom/code-server
When my Docker containers start, I receive the following notification that reads:
Docker Desktop has detected that you shared a Windows file into a WSL 2 container, which may perform poorly. Click here for more details.
My questions are:
What does this mean?
What is the better practice / how should this be avoided?
If the message has been closed, or I've clicked "Don't show again", how can I get to the details of this warning?
I am happy to share the Dockerfile or Docker-Compose setup if needed, but I simply cannot find anything either here on SO or by a Google search that points me in any direction, so I'm not sure where to start. I'm assuming the issue lies in the Dockerfile since that is where we running COPY to move some files around.
Docker Version: Docker Desktop 2.4.0.0 (48506) Community
Operating System: Windows 10 Pro (version 10.0.19041)
This error means that accessing files on the Windows host file system from a Linux container will perform a little slower than accessing files that are already in a Linux filesystem. Accessing Windows files from the Linux container will perform like accessing files on a remote file share.
Docker and Microsoft recommend avoiding this by storing your source files in a WSL2 distro's file system (which you can bind mount to the container) or building your container image to include all the files needed rather than storing your files in the Windows file system.
If you've clicked "Don't show again", you can get to the details of this message by going to Develop with Docker and WSL 2.
For more information, Docker for Windows Best Practices says:
Linux containers only receive file change events (“inotify events”) if the original files are stored in the Linux filesystem. For example, some web development workflows rely on inotify events for automatic reloading when files have changed.
Performance is much higher when files are bind-mounted from the Linux filesystem, rather than remoted from the Windows host. Therefore avoid docker run -v /mnt/c/users:/users (where /mnt/c is mounted from Windows).
Instead, from a Linux shell use a command like docker run -v ~/my-project:/sources <my-image> where ~ is expanded by the Linux shell to $HOME.
Microsoft's Comparing WSL 1 and WSL 2 article has a whole section on Performance across OS file systems, and its opening paragraph says:
We recommend against working across operating systems with your files, unless you have a specific reason for doing so. For the fastest performance speed, store your files in the WSL file system if you are working in a Linux command line (Ubuntu, OpenSUSE, etc). If you're working in a Windows command line (PowerShell, Command Prompt), store your files in the Windows file system.
Also, the Docker blog article Docker Desktop: WSL 2 Best practices has an "Awesome mounts performance" section that says:
Both your own WSL 2 distro and docker-desktop run on the same utility VM. They share the same Kernel, VFS cache etc. They just run in separate namespaces so that they have the illusion of running totally independently. Docker Desktop leverages that to handle bind mounts from a WSL 2 distro without involving any remote file sharing system. This means that when you mount your project files in a container (with docker run -v ~/my-project:/sources <...>), docker will propagate inotify events and share the same cache as your own distro to avoid reading file content from disk repeatedly.
A little warning though: if you mount files that live in the Windows file system (such as with docker run -v /mnt/c/Users/Simon/windows-project:/sources <...>), you won’t get those performance benefits, as /mnt/c is actually a mountpoint exposing Windows files through a Plan9 file share.
All of that advice is great if you want your primary development workflow to be in Linux. Docker wants you to go "all in" on Linux containers. But if you work primarily in Windows and just want to use a Linux container for a specialized task, then it's fine to click "Don't show again". As Microsoft said, "If you're working in a Windows command line, store your files in the Windows file system."
I run with my main development folder in Windows, and I bind mount it to a Linux container that's just used to execute unit tests. So my full build runs in Windows, then I run all my unit tests in Windows, and I finish by running all my unit tests in a Linux container too. Having Linux bind mount to my Windows folder works fast and great for this scenario where the "dotnet test" call in Linux is just loading and executing the required DLLs from my Windows volume.
This setup may sound like heresy to those that believe containers must be used everywhere, but I love containers for application deployment. I'm not convinced that you need to go all in and do all your development inside a container too. I'm happy with Windows (and VS 2019) as my development environment, and then I use Linux containers for application testing and deployment. So the Windows/WSL2 file system performance hit is a minimal impact to me.
OCI containers are a convenient way to package suitable toolchain for a project so that the development environments are consistent and new project members can start quickly by simply checking out the project and pulling the relevant containers.
Of course I am not talking about projects that simply need a C++ compiler or Node.JS. I am talking about projects that need specific compiler packages that don't work with newer than Fedora 22, projects with special tools that need to be installed manually into strange places, working on multiple projects that have tools that are not co-installable and such. For this kind of things it is easier to have a container than follow twenty installation steps and then pray the bits left from previous project don't break things for you.
However, starting a container with compiler to build a project requires quite a few options on the docker (or podman) command-line. Besides the image name, usually:
mount of the project working directory
user id (because the container should access the mounted files as the user running it)
if the tool needs access to some network resources, it might also need
some credentials, via environment or otherwise
ssh agent socket (mount and environment variable)
if the build process involves building docker containers
docker socket (mount); buildah may work without special setup though
and if is a graphic tool (e.g. IDE)
X socket mount and environment variable
--ipc host to make shared memory work
And then it can get more complicated by other factors. E.g. if the developers are in different departments and don't have access to the same docker repository, their images may be called differently, because docker does not support symbolic names of repositories (podman does though).
Is there some standard(ish) way to handle these options or is everybody just using ad-hoc wrapper scripts?
I use Visual Studio Code Remote - Containers extension to connect the source code to a Docker container that holds all the tools needed to build the code (e.g npm modules, ruby gems, eslint, Node.JS, java). The container contains all the "tools" used to develop/build/test the source code.
Additionally, you can also put the VSCode extensions into the Docker image to help keep VSCode IDE tools portable as well.
https://code.visualstudio.com/docs/remote/containers#_managing-extensions
You can provide a Dockerfile in the source code for newcomers to build the Docker image themselves or attach VSCode to an existing Docker container.
If you need to run a server inside the Docker container for testing purposes, you can expose a port on the container via VSCode, and start hitting the server inside the container with a browser or cURL from the host machine.
Be aware of the known limitations to Visual Studio Code Remote - Containers extension. The one that impacts me the most is the beta support for Alphine Linux. I have often noticed some of the popular Docker Hub images are based on Alphine.
Motivation
As of now, we are using five docker containers (MySQL, PHP, static...) managed by docker-compose. We do only need to access one of them. We now have a local copy of all data inside and sync it from Windows to the container, but that is very slow, VSCode on Windows sometimes randomly locks files causing git rebase origin/master to end in very unpleasant ways.
Desired behaviour
Use VSCode Remote Development extension to:
Edit files inside the container without any mirrored files on Windows
Run git commands (checkout, rebase, merge...)
Run build commands (make, ng, npm)
Still keep Windows as for many developers it is the prefered platform.
Question
Is it possible to develop inside a docker container using VSCode?
I have tried to follow the official guide, but they do seem to require us to have mirrored files. We do also use WSL.
As #FSCKur points out this is the exact scenario VSCode dev containers is supposed to address, but on Windows I've found the performance to be unusable.
I've settled on running VSCode and docker inside a Linux VM on Windows, and have a 96% time saving in things like running up a server and watching code for changes making this setup my preferred way now.
The standardisation of devcontainer.json and being able to use github codespaces if you're away from your normal dev machine make this whole setup a pleasure to use.
see https://stackoverflow.com/a/72787362/183005 for detailed timing comparison and setup details
This is sounds like exactly what I do. My team uses Windows on the desktop, and we develop a containerised Linux app.
We use VSCode dev containers. They are an excellent solution for the scenario.
You may also be able to SSH to your docker host and code on it, but in my view this is less good because you want to keep all customisation "contained" - I have installed a few quality-of-life packages in my dev container which I'd prefer to keep out of my colleague's environments and off the docker host.
We have access to the docker host, so we clone our source on the docker host and mount it through. We also bind-mount folders from the docker host for SQL and Redis data - but that could be achieved with docker volumes instead. IIUC, the workspace folder itself does have to be a bind-mount - in fact, no alternative is allowed in the devcontainer.json file. But since you need permission anyway on the docker daemon, this is probably achievable.
All source code operations happen in the dev container, i.e. in Linux. We commit and push from there, we edit our code there. If we need to work on the repo on our laptops, we pull it locally. No rcopy, no SCP - github is our "sync" mechanism. We previously used vagrant and mounted the source from Windows - the symlinks were an absolute pain for us, but probably anyone who's tried mounting source code from Windows into Linux will have experienced pain over some element or other.
VSCode in a dev container is very similar to the local experience. You will get bash in the terminal. To be real, you probably can't work like this without touching bash. However, you can install PSv7 in the container, and/or a 'better' shell (opinion mine) such as zsh.