hyperhive/nix/module-eval/agent-forge-bao.nix

# `checks.module-eval-agent-forge-bao` — see ./lib.nix for the shared
# rationale (why this suite exists, naming convention, "evaluates
# not executes").
#
# The agent side of the swarm-minted forge token: ../agent-modules/forge-token.nix
# fetches it, and ../agent-modules/forge.nix's readers find it.
{
  pkgs,
  lib,
  self,
  nixosSystem,
}:
let
  inherit
    (import ./lib.nix {
      inherit
        pkgs
        lib
        self
        nixosSystem
        ;
    })
    agentWith
    runGroup
    ;

  forgeUrl = "http://forge.t.local";
  baoAddr = "https://bao.t.local:8200";

  # A forge and a store: the fetch exists and every reader points at it.
  agentForgeBao = agentWith {
    services.hyperhive.agent.bao.addr = baoAddr;
    services.hyperhive.agent.forge.url = forgeUrl;
    services.hyperhive.agent.icon = pkgs.emptyFile;
  };

  # A forge and no store: the absence arm, and what makes the cases above able
  # to fail.
  agentForgeNoBao = agentWith {
    services.hyperhive.agent.forge.url = forgeUrl;
    services.hyperhive.agent.icon = pkgs.emptyFile;
  };

  fetchUnit = machine: machine.systemd.services.hive-agent-forge-token;
  tokenFile = machine: machine.services.hyperhive.agent.forge.tokenFile;
in
let
  cases = [
    {
      # The whole switch is the store address, as for the queue credential.
      name = "an agent with a store address fetches its forge token";
      ok =
        agentForgeBao.systemd.services ? hive-agent-forge-token
        && agentForgeBao.systemd.timers ? hive-agent-forge-token;
    }
    {
      name = "an agent told no store address fetches no forge token";
      ok =
        !(agentForgeNoBao.systemd.services ? hive-agent-forge-token)
        && !(agentForgeNoBao.systemd.timers ? hive-agent-forge-token)
        && !(agentForgeNoBao.systemd.globalEnvironment ? HIVE_FORGE_TOKEN_FILE);
    }
    {
      # The nix half of `swarm_secret_client::forge::agent_token_path` plus the
      # mount. Spelled out: the Rust test pins `swarm/agents/atlas/forge-token`,
      # and a drift between the two is a fetch that 404s forever and says
      # "not minted yet".
      name = "the fetch reads the agent's own forge-token path";
      ok =
        let
          name = agentForgeBao.services.hyperhive.agent.user.name;
        in
        lib.hasInfix "secret/swarm/agents/${name}/forge-token" (fetchUnit agentForgeBao).script;
    }
    {
      # One store identity per agent: the fetch presents the same certificate
      # the identity check proves. Every `BAO_*` value is an address or a
      # `%d/` path, never a value.
      name = "the fetch presents the agent's own store identity, by path";
      ok =
        let
          u = fetchUnit agentForgeBao;
          e = u.environment;
        in
        builtins.elem "hive-agent-bao-cert" u.serviceConfig.LoadCredential
        && builtins.elem "hive-agent-bao-key" u.serviceConfig.LoadCredential
        && e.BAO_ADDR == baoAddr
        && e.BAO_CLIENT_CERT == "%d/hive-agent-bao-cert"
        && e.BAO_CLIENT_KEY == "%d/hive-agent-bao-key";
    }
    {
      # The field is the secret. It goes to a file by redirect and is never
      # echoed.
      name = "the fetch writes the token by redirect and never echoes it";
      ok =
        let
          s = (fetchUnit agentForgeBao).script;
        in
        lib.hasInfix "-field=value" s
        && lib.hasInfix "> ${lib.escapeShellArg "/run/hive-agent-forge-token/token.new"}" s
        && !(lib.hasInfix "echo \"$(bao" s)
        && !(lib.hasInfix "echo $(bao" s);
    }
    {
      # A timer can only start an inactive unit, so the fetch must not stay
      # active; the directory, and the token in it, has to outlive each run.
      name = "the fetch can be re-run by its timer without losing the token";
      ok =
        let
          c = (fetchUnit agentForgeBao).serviceConfig;
        in
        !c.RemainAfterExit
        && c.RuntimeDirectory == "hive-agent-forge-token"
        && c.RuntimeDirectoryPreserve == "yes"
        && c.UMask == "0377";
    }
    {
      # Rename in only on a change: a reader never sees half a token, and the
      # avatar watcher does not fire on every timer tick.
      name = "the fetch swaps the token in by rename, only when it changed";
      ok =
        let
          s = (fetchUnit agentForgeBao).script;
        in
        lib.hasInfix "cmp -s" s && lib.hasInfix "mv -f" s;
    }
    {
      # Every unit and the bash-task runner find the token through this. A
      # path, never the value.
      name = "the fetched token's path is published to every unit";
      ok =
        agentForgeBao.systemd.globalEnvironment.HIVE_FORGE_TOKEN_FILE == tokenFile agentForgeBao
        && tokenFile agentForgeBao == "/run/hive-agent-forge-token/token";
    }
    {
      # The avatar sync has to re-fire when the swarm's token lands, which is
      # the file the fetch writes, not the state-dir file nothing writes any
      # more.
      name = "the avatar watcher follows the fetched token";
      ok =
        agentForgeBao.systemd.paths.forge-avatar-sync.pathConfig.PathChanged == tokenFile agentForgeBao
        && builtins.elem "hive-agent-forge-token.service" agentForgeBao.systemd.services.forge-avatar-sync.after;
    }
    {
      # Both readers take the fetched token first and fall back to the state
      # file, which is still the only copy for an agent with no store identity.
      name = "the avatar sync reads the fetched token before the state file";
      ok =
        let
          s = agentForgeBao.systemd.services.forge-avatar-sync.script;
          name = agentForgeBao.services.hyperhive.agent.user.name;
          fetched = lib.escapeShellArg (tokenFile agentForgeBao);
          state = lib.escapeShellArg "/agents/${name}/state/forge-token";
        in
        lib.hasInfix "for f in ${fetched} ${state}; do" s;
    }
    {
      # tea-login copied the token into ~/.config/tea/config.yml, which
      # docs/swarm/credentials.md forbids for a store secret. Gone, with the
      # package it configured.
      name = "no tea-login unit and no tea package";
      ok =
        !(agentForgeBao.systemd.services ? tea-login)
        && !(agentForgeNoBao.systemd.services ? tea-login)
        && !(builtins.elem pkgs.tea agentForgeBao.environment.systemPackages);
    }
  ];
in
runGroup "agent-forge-bao" cases