Once: Cache CLI Commands(github.com)
54 pointsby baquero6 hours ago10 comments
  • deadbunny4 hours ago
    I've always wanted to deal with cache invalidation in my terminal.
  • aktau4 hours ago
    These kinds of tools are very useful. I have my own called memo (which is just a shell script: https://github.com/aktau/dotfiles/blob/master/bin/memo).

    It was discussed in https://news.ycombinator.com/item?id=45670052 and others chimed in with their own (like bkt(1) and up(1)).

    The main differences I see:

      - memo doesn't need to be built (its a shell script)
  - once keeps output cache in a running daemon. By contrast, memo stores content under /tmp with whatever the best compression available is (it prefers zstd). There's trade-offs in that. More pareto-optimal from the security front may be to have a sort of session key and to compress-then-encrypt files on disk.
    • thomascountz32 minutes ago
      Hey! I use your shell script after seeing it on HN awhile ago. It's very handy (I find myself reaching for it as if it's a built-in) and I appreciate its design (I learned a few things reading it)!
  • hecomo22 minutes ago
    This looks awesome. Thanks for making this.

    Been using this, for similar cli output catching. https://github.com/dimo414/bkt

    Wondering what you think about the two, and what are the good reasons to use one vs the other? (Maybe: once is more actively developed? bkt hasn't been active for a year).

  • __MatrixMan__2 hours ago
    I dream of applications that expose sufficient metadata about their outputs such that the OS can know if rerunning is necessary without me needing to specify.

    Nixos does this for builds, but I've not seen it generalized to arbitrary processes.

  • xuhu4 hours ago
    I wish this worked without prefixing the commands with "once". Especially if I ran a command with verbose output and afterwards decided I wanted to grep something from it. Terminals have the output in their scrollback buffer and maybe it's just a matter of writing an "output" command that lets me run:

        $ cmake ..
    $ output | grep "libssl version"
    • ctippett3 hours ago
      You could probably achieve something like that using Fish shell and their fish_preexec and fish_postexec event hooks.

      Edit: Nope, looks like you can't. You only get the invoked command and no output.

      • stirfish2 hours ago
        Could you use preexec + tee?
  • giancarlostoro2 hours ago
    > The typical use case: reading secrets from 1Password without approving every single read with your fingerprint.

    Uh I dont know about that one chief.

    • alex0ptr2 hours ago
      Yes - but I'm out of ideas. How else support long running agents without leaving secrets in files or by default exposed in the environment. That way I get notified the first time before they ask for credentials.
      • stryan30 minutes ago
        Fnox (by jdx of mise) supports fetching secrets and caching the results either in local age encrypted files or in a background daemon (in memory only) to minimize repeated gets. The daemon is per terminal instance too I believe so you fetching a secret once doesn't store it for the whole session.

        It's not a perfect fix but it keeps secrets out of env with (so far for me) minimal inconvenience.

      • mehackernewsacc2 hours ago
        Does https://secretspec.dev/ address your use case?
        • alex0ptr2 hours ago
          That looks pretty cool - even supports caching. Will take a deeper look. Thx
      • giancarlostoro2 hours ago
        The same agents that could potentially leak your secrets? I would rather not give a hacker a cached session that unlocks the keys to the kingdom.

        I'll take security by inconvenience over building what becomes the primary reason for a security incident.

        • alex0ptr2 hours ago
          If I already approved it once I already have to assume it could have been leaked. The cache doesn't change much about it if the agent / tenant is asking for something it already has.
      • devmoran hour ago
        Don't give secrets to agents at all that you don't plan on revoking immediately after.

        If you have allowed an agent to access any kind of credential, you should assume it is no longer private.

  • stingraycharles4 hours ago
    Seems well-designed, but what’s the use case? I’m trying to think of them but my creativity is failing me.
    • adregan4 hours ago
      I have a small fish function that does something similar. It saves output to a file in XDG_CACHE_HOME. I wouldn’t use it for sensitive items like passwords or tokens in the examples, but I do use it for scripts that need to fetch some data from the network.

      For example, I have a script for automating the creation of PRs which fetches the available labels for a repo from github and presents them with fzf multi select. I store the labels with a TTL of a week so that I don’t have to fetch them every time and the script compares the file’s age against the desired TTL to invalidate.

      I find it useful for augmenting other programs, but I’m not typically using it on the cli directly.

    • frizlab4 hours ago
      From the example in the Readme, I guess retrieving a token from an API, using a secret fetched from a secure vault that requests a password or TouchID validation.

      Not sure if there could be other interesting uses. I can’t think of one anyways.

      • alex0ptr2 hours ago
        Yes, exactly. This is especially frustrating when I leave an agent running for a long time and it gets stuck on my build scripts because it's waiting for my approval.

        I just want to avoid leaving my credentials and secrets on the filesystem.

        EDIT: I use a lot of direnv / mise. So reloading credentials with different values is common.

    • whilenot-dev4 hours ago
      I have the same question, especially since any CLI output can be stored explicitly in some variable or temp file. What's the advantage of storing the output implicitly?
      • alex0ptr2 hours ago
        I don't want to store them in a file since I don't trust my agents with that data. Instead, the daemon secures the values using/under an HMAC key, making them virtually impossible to guess.
  • newadaysan hour ago
    Congratulations. What is Word Error Rate? We have a few use cases for something like that at newcare.app
  • baquero6 hours ago
    Do you have CLI calls that you want to cache? Here you go!
  • singularityisne2 hours ago
    [flagged]