[Arch Refactor for Agent Runtime]: Deprecating SSH-based communication and use EventStream

[xingyaoww]

What problem or use case are you trying to solve?

Right now, the backend mainly relies on ssh to communicate with sandbox, which does not fit too well with our current Event Stream-based communication. The requirement of the backend to know the existence of "ssh" makes thing much harder to support different runtimes/docker images (#1387, e.g., we need to automatically install sshd if user bring their own docker images without it - and it can get tricky very quickly since sshd may need to be installed differently across different linux distributions) and creating hosted version (#1086).

Describe the UX of the solution you'd like

I imagine our next step in architecture will be able to support arbitrary docker image sandbox/runtime by creating one piece of software called od-runtime-client and automatically installing it into the user-provided sandbox (if it wasn't installed already - this is already partially done in #2101).

Then, at the entry point of each docker sandbox, od-runtime-client will be started:

• it will connect to backend's event stream (via WebSocket well it is currently implemented as REST API), handle event stream communication to/from other sources. Resolved by Add websocket runtime and od-client-runtime #2603
  • For example, CmdRunAction can be directly stream from the agent and received by od-runtime-client, and od-runtime-client can maintains a pexcept session that directly interact with /bin/bash to execute that command.
  • This will allows us to get rid of the SSH requirement altogether
• be docker-image agnostic to support arbitrary user-provided sandbox images
  • Partially done in Make plugins sandbox-agnostic #2101
  • Partially done in [Arch] Implement EventStream Runtime Client with Jupyter Support using Agnostic Sandbox #2879, require further testing
  • We need to shrink down the size of our dependency required to install in the runtime-client (now we need to install everything opendevin needed), so we can build any user-provide images faster (Remove torch dependency if possible #690 is related): [Runtime] Reduce dependency to speed up CI and reduce image size #3195
• A browser can be maintained as a plugin for od-runtime-client, so we can get rid of the current browsing running on the backend (cc @frankxu2004). Done in [Arch] EventStreamRuntime supports browser #2899
  • It will also make it easier for (multimodal) agent to use the browser to browse some local multimedia file (e.g., goto url file://image.jpg)
  • It will also be more natural to integrate browser primitives (e.g., goto_url) into agentskills library when they are in the same container.
• maintain an IPython + agentskills library with the od-runtime-client. Done in [Arch] Implement EventStream Runtime Client with Jupyter Support using Agnostic Sandbox #2879
• we might also consider merging all the existing plugins into od-runtime-client. [Arch] Implement EventStream Runtime Client with Jupyter Support using Agnostic Sandbox #2879
• [ ] replace <execute_bash> with a execute_bash agentskills. (no plan for me)
• Extensively tests EventStream runtime to make sure it is in feature parity as our existing ServerRuntime:
  • Add tests for sandbox: Migrate multi-line-bash-related sandbox tests into runtime tests and fix multi-line issue #3128
  • Add integration tests: [Arch] Support integration tests using EventStream Runtime #3184
• Make sure EventStreamRuntime works across all the evaluation suite. Run SWE-Bench to ensure there's no performance degradation: [Refactor, Evaluation] Refactor and clean up evaluation harness to remove global config and use EventStreamRuntime #3230
• Deprecate and remove ServerRuntime, and switch to EventStreamRuntime by default: (arch) Switch default runtime to EventStream Runtime #3271

Do you have thoughts on the technical implementation?

Due to the diversity of user-provided docker images we might need to support, I propose we use some package manager like miniforge that is already multi-platform to maintain the environment (miniforge can install different python version, and even maintains its own glibc version to circumvent some system-level restriction, e.g., glibc version too old) and dependencies of od-runtime-client. So the workflow of user-bring docker sandbox would be (essentially what we implemented in #2101):

1. Detect if a user brings an image that comes with already installed od-runtime-client
2. If not, we create a temporary Dockerfile, FROM user-provided-docker, then build that image with a suffix _od
3. Then we use ${SANDBOX_CONTAINER_IMAGE}_od to start the sandbox, and assume every dependencies is met.

Describe alternatives you've considered

Additional context

[iFurySt]

The design is great.

If I understand you correctly, the od-runtime-client will install all needed packages/plugins to the target sandbox to smoothly execute all tasks received from the OD server through the WebSocket connection.

I have a few worries about the dependencies, package installation, and plugin management.

we might also consider merging all the existing plugins into od-runtime-client

Will the od-runtime-client grow significantly over time, or does it only consist of basic plugins and it can pull others from the remote?

BTW, how do we define the plugins? Is it possible to let the users define their own plugins?

[xingyaoww]

Will the od-runtime-client grow significantly over time, or does it only consist of basic plugins and it can pull others from the remote?

This is a very good question! For simplicity now, we can just say we want to pack everything at the beginning (maybe keep the "setup.sh" based workflow for our plugins now).

BTW, how do we define the plugins? Is it possible to let the users define their own plugins?

Now user can already define their own plugins via setup.sh.

But in the long term, we should consider make this plugin management very easy, so that user can easily define their plugins. I have a preliminary thought about using a Python package manager like pip for plugin management -- user can bring their own pip package to the system, and we basically need a pip install to install it.

Besides this, I'm also debating the difference between plugins and agentskills:

• I view plugins more like a heavy OD-specific dependency that is required to support certain things (e.g., if we have a VSCode frontend, we may have a vscode plugin that needs to be activated inside od-runtime-client so it can directly take to vscode for code editing actions). This should/can be transparent to the end user that just want to use OD to solve tasks.

• agentskills is more like a custom library of tools that user can easily add new capabilities into it, whether it is for support new modality (e.g., transcribe_speech_to_text) or customized workflow (e.g., lookup_my_calendar). User should be aware of this, and can new actions to it when needed. I'm thinking maybe we should focus more on lowering the entry barrier for user here?

[yufansong]

Working on this recently, will open a draft PR when finish the basic framework.

[rbren]

Very excited for this! I have two basic concerns here though:

• How will we manage state without an SSH session (e.g. environment variables and cwd)?
• The browser installation is very tricky, and will be hard to do with a BYOImage. My guess is we'll have the most luck using a separate browser container

Re: plugins, IMO we should see if we can remove this entirely. It will be hard to create plugins that support every possible container OS, and create maintenance headaches. What are we currently using plugins for at this point?

[yufansong]

Hi @rbren , my basic plan:

1. implememnt a od-runtime-client (run inside the container)
   1.1 initialization work (include plugin and agentskills)
   1.2 open a websocket to receive cmd to execute
   1.3 use pexcept to maintain a bash session, then can be stateful (solve the environment variables and cwd problem)
2. Implement websocket sandbox to communicate with the websocket in od-runtime-client

Do you have any suggestions?

How will we manage state without an SSH session (e.g. environment variables and cwd)?

It should solved by pexcept

The browser installation is very tricky, and will be hard to do with a BYOImage

I have not investigate this tech details. My basic idea is try to do it in od-runtime-client iniitialization. Still need more time to check our current browse code.

What are we currently using plugins for at this point?

In the code definition, only AgentSkillsRequirement() and JupyterRequirement()