difftreelog
feat basic lustration helper
in: trunk
3 files changed
cmds/fleet/src/cmds/build_systems.rsdiffbeforeafterboth--- a/cmds/fleet/src/cmds/build_systems.rs
+++ b/cmds/fleet/src/cmds/build_systems.rs
@@ -1,6 +1,6 @@
use std::{env::current_dir, os::unix::fs::symlink, path::PathBuf, time::Duration};
-use anyhow::{anyhow, bail, Result};
+use anyhow::{anyhow, bail, Context, Result};
use clap::{Parser, ValueEnum};
use fleet_base::{
host::{Config, ConfigHost, DeployKind},
@@ -132,10 +132,10 @@
disable_rollback: bool,
) -> Result<()> {
let deploy_kind = host.deploy_kind().await?;
- if deploy_kind == DeployKind::NixosInstall
+ if (deploy_kind == DeployKind::NixosInstall || deploy_kind == DeployKind::NixosLustrate)
&& !matches!(action, DeployAction::Boot | DeployAction::Upload)
{
- bail!("nixos-install deploy kind only supports boot and upload actions");
+ bail!("{deploy_kind:?} deploy kind only supports boot and upload actions");
}
let mut failed = false;
@@ -184,6 +184,17 @@
}
}
}
+ if deploy_kind == DeployKind::NixosLustrate {
+ // Fleet could also create this file, but as this operation is potentially disruptive,
+ // make user do it themself.
+ if !host.file_exists("/etc/NIXOS_LUSTRATE").await? {
+ bail!("/etc/NIXOS_LUSTRATE should be created on remote host");
+ }
+ // Wanted by NixOS to recognize the system as NixOS.
+ let mut cmd = host.cmd("touch").await?;
+ cmd.arg("/etc/NIXOS");
+ cmd.sudo().run().await.context("creating /etc/NIXOS")?;
+ }
if deploy_kind == DeployKind::NixosInstall {
info!(
"running nixos-install to switch profile, install bootloader, and perform activation"
@@ -247,6 +258,9 @@
};
let switch_script = specialised.join("bin/switch-to-configuration");
let mut cmd = host.cmd(switch_script).in_current_span().await?;
+ if deploy_kind == DeployKind::NixosLustrate {
+ cmd.env("NIXOS_INSTALL_BOOTLOADER", "1");
+ }
cmd.env("FLEET_ONLINE_ACTIVATION", "1")
.arg(action.name().expect("upload.should_activate == false"));
if let Err(e) = cmd.sudo().run().in_current_span().await {
crates/fleet-base/src/host.rsdiffbeforeafterboth1use std::{2 cell::OnceCell,3 collections::BTreeSet,4 ffi::{OsStr, OsString},5 fmt::Display,6 io::Write,7 ops::Deref,8 path::PathBuf,9 str::FromStr,10 sync::{Arc, Mutex, MutexGuard, OnceLock},11};1213use anyhow::{anyhow, bail, ensure, Context, Result};14use fleet_shared::SecretData;15use nix_eval::{nix_go, nix_go_json, util::assert_warn, NixSession, Value};16use openssh::SessionBuilder;17use serde::de::DeserializeOwned;18use tempfile::NamedTempFile;1920use crate::{21 command::MyCommand,22 fleetdata::{FleetData, FleetSecret, FleetSharedSecret},23};2425pub struct FleetConfigInternals {26 /// Fleet project directory, containing fleet.nix file.27 pub directory: PathBuf,28 /// builtins.currentSystem29 pub local_system: String,30 pub data: Mutex<FleetData>,31 pub nix_args: Vec<OsString>,32 /// fleet_config.config33 pub config_field: Value,34 // TODO: Remove with connectivity refactor35 pub localhost: String,3637 /// import nixpkgs {system = local};38 pub default_pkgs: Value,39 /// inputs.nixpkgs40 pub nixpkgs: Value,4142 pub nix_session: NixSession,43}4445// TODO: Make field not pub46#[derive(Clone)]47pub struct Config(pub Arc<FleetConfigInternals>);4849impl Deref for Config {50 type Target = FleetConfigInternals;5152 fn deref(&self) -> &Self::Target {53 &self.054 }55}5657#[derive(Clone, Copy, Debug)]58pub enum EscalationStrategy {59 Sudo,60 Run0,61 Su,62}6364#[derive(Clone, PartialEq, Copy, Debug)]65pub enum DeployKind {66 /// NixOS => NixOS managed by fleet67 UpgradeToFleet,68 /// NixOS managed by fleet => NixOS managed by fleet69 Fleet,70 /// Remote host has /mnt, /mnt/boot mounted,71 /// generated config is added to fleet configuration.72 NixosInstall,73 /// Remote host has some system and nix installed in multi-user mode (/nix is owned by root),74 /// generated config is added to fleet configuration,75 /// and /etc/NIXOS_LUSTRATE exists, fleet will perform the rest.76 NixosLustrate,77}7879impl FromStr for DeployKind {80 type Err = anyhow::Error;81 fn from_str(s: &str) -> std::result::Result<Self, Self::Err> {82 match s {83 "upgrade-to-fleet" => Ok(Self::UpgradeToFleet),84 "fleet" => Ok(Self::Fleet),85 "nixos-install" => Ok(Self::NixosInstall),86 v => bail!("unknown deploy_kind: {v}; expected on of \"upgrade-to-fleet\", \"fleet\", \"nixos-install\""),87 }88 }89}90pub struct ConfigHost {91 config: Config,92 pub name: String,93 groups: OnceCell<Vec<String>>,9495 deploy_kind: OnceCell<DeployKind>,9697 pub host_config: Option<Value>,98 pub nixos_config: OnceCell<Value>,99 pub pkgs_override: Option<Value>,100101 // TODO: Move command helpers away with connectivity refactor102 pub local: bool,103 pub session: OnceLock<Arc<openssh::Session>>,104}105// TODO: Move command helpers away with connectivity refactor106impl ConfigHost {107 pub fn set_deploy_kind(&self, kind: DeployKind) {108 self.deploy_kind109 .set(kind)110 .ok()111 .expect("deploy kind is already set");112 }113 pub async fn deploy_kind(&self) -> Result<DeployKind> {114 if let Some(kind) = self.deploy_kind.get() {115 return Ok(kind.clone());116 }117 let is_fleet_managed = match self.file_exists("/etc/FLEET_HOST").await {118 Ok(v) => v,119 Err(e) => {120 bail!("failed to query remote system kind: {}", e);121 }122 };123 if !is_fleet_managed {124 bail!(indoc::indoc! {"125 host is not marked as managed by fleet126 if you're not trying to lustrate/install system from scratch,127 you should either128 1. manually create /etc/FLEET_HOST file on the target host,129 2. use ?deploy_kind=fleet host argument if you're upgrading from older version of fleet130 3. use ?deploy_kind=upgrade_to_fleet if you're upgrading from plain nixos to fleet-managed nixos131 "});132 }133 // TOCTOU is possible134 let _ = self.deploy_kind.set(DeployKind::Fleet);135 Ok(self136 .deploy_kind137 .get()138 .expect("deploy kind is just set")139 .clone())140 }141 pub async fn escalation_strategy(&self) -> Result<EscalationStrategy> {142 // Prefer sudo, as run0 has some gotchas with polkit143 // and too many repeating prompts.144 if (self.find_in_path("sudo").await).is_ok() {145 return Ok(EscalationStrategy::Sudo);146 }147 if (self.find_in_path("run0").await).is_ok() {148 return Ok(EscalationStrategy::Run0);149 }150 Ok(EscalationStrategy::Su)151 }152 async fn open_session(&self) -> Result<Arc<openssh::Session>> {153 assert!(!self.local, "do not open ssh connection to local session");154 // FIXME: TOCTOU155 if let Some(session) = &self.session.get() {156 return Ok((*session).clone());157 };158 let session = SessionBuilder::default();159 let session = session160 .connect(&self.name)161 .await162 .map_err(|e| anyhow!("ssh error while connecting to {}: {e}", self.name))?;163 let session = Arc::new(session);164 self.session.set(session.clone()).expect("TOCTOU happened");165 Ok(session)166 }167 pub async fn mktemp_dir(&self) -> Result<String> {168 let mut cmd = self.cmd("mktemp").await?;169 cmd.arg("-d");170 let path = cmd.run_string().await?;171 Ok(path.trim_end().to_owned())172 }173 pub async fn file_exists(&self, path: impl AsRef<OsStr>) -> Result<bool> {174 let mut cmd = self.cmd("sh").await?;175 cmd.arg("-c")176 .arg("test -e \"$1\" && echo true || echo false")177 .arg("_")178 .arg(path);179 Ok(cmd.run_value().await?)180 }181 pub async fn read_file_bin(&self, path: impl AsRef<OsStr>) -> Result<Vec<u8>> {182 let mut cmd = self.cmd("cat").await?;183 cmd.arg(path);184 cmd.run_bytes().await185 }186 pub async fn read_file_text(&self, path: impl AsRef<OsStr>) -> Result<String> {187 let mut cmd = self.cmd("cat").await?;188 cmd.arg(path);189 cmd.run_string().await190 }191 pub async fn read_dir(&self, path: impl AsRef<OsStr>) -> Result<Vec<String>> {192 let mut cmd = self.cmd("ls").await?;193 cmd.arg(path);194 let out = cmd.run_string().await?;195 let mut lines = out.split('\n');196 if let Some(last) = lines.next_back() {197 ensure!(last.is_empty(), "output of ls should end with newline");198 }199 Ok(lines.map(ToOwned::to_owned).collect())200 }201 #[allow(dead_code)]202 pub async fn read_file_json<D: DeserializeOwned>(&self, path: impl AsRef<OsStr>) -> Result<D> {203 let text = self.read_file_text(path).await?;204 Ok(serde_json::from_str(&text)?)205 }206 pub async fn read_env(&self, env: &str) -> Result<String> {207 let mut cmd = self.cmd("printenv").await?;208 cmd.arg(env);209 cmd.run_string().await210 }211 pub async fn find_in_path(&self, command: &str) -> Result<String> {212 // // `which` is not a part of coreutils, and it might not exist on machine.213 // let path = self.read_env("PATH").await?;214 // // Assuming delimiter is :, we don't work with windows host, this check will be much215 // // more sophisticated in remowt backend (and quicker, since actual PATH search will be done on remote machine)216 // for ele in path.split(':') {217 // let test_path = format!("{ele}/{cmd}");218 // test -x etc219 // }220 // let mut cmd = self.cmd("printenv").await?;221 // cmd.arg(env);222 // Ok(cmd.run_string().await?)223 // Assuming this is an environment issue if which doesn't exist, will be fixed with remowt.224 let mut cmd = self225 .cmd_escalation(226 // Not used227 EscalationStrategy::Su,228 "which",229 )230 .await?;231 cmd.arg(command);232 cmd.run_string().await233 }234 pub async fn read_file_value<D: FromStr>(&self, path: impl AsRef<OsStr>) -> Result<D>235 where236 <D as FromStr>::Err: Display,237 {238 let text = self.read_file_text(path).await?;239 D::from_str(&text).map_err(|e| anyhow!("failed to parse value: {e}"))240 }241 pub async fn cmd(&self, cmd: impl AsRef<OsStr>) -> Result<MyCommand> {242 self.cmd_escalation(self.escalation_strategy().await?, cmd)243 .await244 }245 pub async fn cmd_escalation(246 &self,247 escalation: EscalationStrategy,248 cmd: impl AsRef<OsStr>,249 ) -> Result<MyCommand> {250 if self.local {251 Ok(MyCommand::new(escalation, cmd))252 } else {253 let session = self.open_session().await?;254 Ok(MyCommand::new_on(escalation, cmd, session))255 }256 }257 pub async fn nix_cmd(&self) -> Result<MyCommand> {258 let mut nix = self.cmd("nix").await?;259 nix.args([260 "--extra-experimental-features",261 "nix-command",262 "--extra-experimental-features",263 "flakes",264 ]);265 Ok(nix)266 }267268 pub async fn decrypt(&self, data: SecretData) -> Result<Vec<u8>> {269 ensure!(data.encrypted, "secret is not encrypted");270 let mut cmd = self.cmd("fleet-install-secrets").await?;271 cmd.arg("decrypt").eqarg("--secret", data.to_string());272 let encoded = cmd273 .sudo()274 .run_string()275 .await276 .context("failed to call remote host for decrypt")?;277 let data: SecretData = encoded.parse().map_err(|e| anyhow!("{e}"))?;278 ensure!(!data.encrypted, "secret came out encrypted");279 Ok(data.data)280 }281 pub async fn reencrypt(&self, data: SecretData, targets: Vec<String>) -> Result<SecretData> {282 ensure!(data.encrypted, "secret is not encrypted");283 let mut cmd = self.cmd("fleet-install-secrets").await?;284 cmd.arg("reencrypt").eqarg("--secret", data.to_string());285 for target in targets {286 let key = self.config.key(&target).await?;287 cmd.eqarg("--targets", key);288 }289 let encoded = cmd290 .sudo()291 .run_string()292 .await293 .context("failed to call remote host for decrypt")?;294 let data: SecretData = encoded.parse().map_err(|e| anyhow!("{e}"))?;295 ensure!(data.encrypted, "secret came out not encrypted");296 Ok(data)297 }298 /// Returns path for futureproofing, as path might change i.e on conversion to CA299 pub async fn remote_derivation(&self, path: &PathBuf) -> Result<PathBuf> {300 if self.local {301 // Path is located locally, thus already trusted.302 return Ok(path.to_owned());303 }304 let mut nix = MyCommand::new(305 // Not used306 EscalationStrategy::Su,307 "nix",308 );309 nix.arg("copy").arg("--substitute-on-destination");310311 match self.deploy_kind().await? {312 DeployKind::Fleet | DeployKind::UpgradeToFleet | DeployKind::NixosLustrate => {313 nix.comparg("--to", format!("ssh-ng://{}", self.name));314 }315 DeployKind::NixosInstall => {316 nix317 // Signature checking makes no sense with remote-store store argument set, as we're not even interacting with remote nix daemon318 .arg("--no-check-sigs")319 .comparg(320 "--to",321 format!("ssh-ng://root@{}-install?remote-store=/mnt", self.name),322 );323 }324 }325 nix.arg(path);326 nix.run_nix().await.context("nix copy")?;327 Ok(path.to_owned())328 }329 pub async fn systemctl_stop(&self, name: &str) -> Result<()> {330 let mut cmd = self.cmd("systemctl").await?;331 cmd.arg("stop").arg(name);332 cmd.sudo().run().await333 }334 pub async fn systemctl_start(&self, name: &str) -> Result<()> {335 let mut cmd = self.cmd("systemctl").await?;336 cmd.arg("start").arg(name);337 cmd.sudo().run().await338 }339340 pub async fn rm_file(&self, path: impl AsRef<OsStr>, sudo: bool) -> Result<()> {341 let mut cmd = self.cmd("rm").await?;342 cmd.arg("-f").arg(path);343 if sudo {344 cmd = cmd.sudo()345 }346 cmd.run().await347 }348}349impl ConfigHost {350 // TOCTOU is possible here in case if config is changed, but this case is not handled anywhere anyway,351 // assuming getting tags always returns the same value.352 pub async fn tags(&self) -> Result<Vec<String>> {353 if let Some(v) = self.groups.get() {354 return Ok(v.clone());355 }356 let Some(host_config) = &self.host_config else {357 return Ok(vec![]);358 };359 let tags: Vec<String> = nix_go_json!(host_config.tags);360361 let _ = self.groups.set(tags.clone());362363 Ok(tags)364 }365 pub async fn nixos_config(&self) -> Result<Value> {366 if let Some(v) = self.nixos_config.get() {367 return Ok(v.clone());368 }369 let Some(host_config) = &self.host_config else {370 bail!("local host has no nixos_config");371 };372 let nixos_config = nix_go!(host_config.nixos.config);373 assert_warn("nixos config evaluation", &nixos_config).await?;374375 let _ = self.nixos_config.set(nixos_config.clone());376377 Ok(nixos_config)378 }379380 pub async fn list_configured_secrets(&self) -> Result<Vec<String>> {381 let nixos = self.nixos_config().await?;382 let secrets = nix_go!(nixos.secrets);383 let mut out = Vec::new();384 for name in secrets.list_fields().await? {385 let secret = nix_go!(secrets[{ name }]);386 let is_shared: bool = nix_go_json!(secret.shared);387 if is_shared {388 continue;389 }390 out.push(name);391 }392 Ok(out)393 }394 pub async fn secret_field(&self, name: &str) -> Result<Value> {395 let nixos = self.nixos_config().await?;396 Ok(nix_go!(nixos.secrets[{ name }]))397 }398399 /// Packages for this host, resolved with nixpkgs overlays400 pub async fn pkgs(&self) -> Result<Value> {401 if let Some(value) = &self.pkgs_override {402 return Ok(value.clone());403 }404 let Some(host_config) = &self.host_config else {405 bail!("local host has no host_config");406 };407 // TODO: Should nixos.options be cached?408 Ok(nix_go!(host_config.nixos.options._module.args.value.pkgs))409 }410}411412impl Config {413 pub async fn tagged_hostnames(&self, tag: &str) -> Result<Vec<String>> {414 let config = &self.config_field;415 let tagged: Vec<String> = nix_go_json!(config.taggedWith[{ tag }]);416 Ok(tagged)417 }418 pub async fn expand_owner_set(&self, owners: Vec<String>) -> Result<BTreeSet<String>> {419 let mut out = BTreeSet::new();420 for owner in owners {421 if let Some(tag) = owner.strip_prefix('@') {422 let hosts = self.tagged_hostnames(tag).await?;423 out.extend(hosts);424 } else {425 out.insert(owner);426 }427 }428 Ok(out)429 }430 pub fn local_host(&self) -> ConfigHost {431 ConfigHost {432 config: self.clone(),433 name: "<virtual localhost>".to_owned(),434 host_config: None,435 nixos_config: OnceCell::new(),436 groups: {437 let cell = OnceCell::new();438 let _ = cell.set(vec![]);439 cell440 },441 pkgs_override: Some(self.default_pkgs.clone()),442443 local: true,444 session: OnceLock::new(),445 deploy_kind: OnceCell::new(),446 }447 }448449 pub async fn host(&self, name: &str) -> Result<ConfigHost> {450 let config = &self.config_field;451 let host_config = nix_go!(config.hosts[{ name }]);452453 Ok(ConfigHost {454 config: self.clone(),455 name: name.to_owned(),456 host_config: Some(host_config),457 nixos_config: OnceCell::new(),458 groups: OnceCell::new(),459 pkgs_override: None,460461 // TODO: Remove with connectivit refactor462 local: self.localhost == name,463 session: OnceLock::new(),464 deploy_kind: OnceCell::new(),465 })466 }467 pub async fn list_hosts(&self) -> Result<Vec<ConfigHost>> {468 let config = &self.config_field;469 let names = nix_go!(config.hosts).list_fields().await?;470 let mut out = vec![];471 for name in names {472 out.push(self.host(&name).await?);473 }474 Ok(out)475 }476 // TODO: Replace usages with .host().nixos_config477 pub async fn system_config(&self, host: &str) -> Result<Value> {478 let fleet_field = &self.config_field;479 Ok(nix_go!(fleet_field.hosts[{ host }].nixos.config))480 }481482 /// Shared secrets configured in fleet.nix or in flake483 pub async fn list_configured_shared(&self) -> Result<Vec<String>> {484 let config_field = &self.config_field;485 Ok(nix_go!(config_field.sharedSecrets).list_fields().await?)486 }487 /// Shared secrets configured in fleet.nix488 pub fn list_shared(&self) -> Vec<String> {489 let data = self.data();490 data.shared_secrets.keys().cloned().collect()491 }492 pub fn has_shared(&self, name: &str) -> bool {493 let data = self.data();494 data.shared_secrets.contains_key(name)495 }496 pub fn replace_shared(&self, name: String, shared: FleetSharedSecret) {497 let mut data = self.data_mut();498 data.shared_secrets.insert(name.to_owned(), shared);499 }500 pub fn remove_shared(&self, secret: &str) {501 let mut data = self.data_mut();502 data.shared_secrets.remove(secret);503 }504505 pub fn list_secrets(&self, host: &str) -> Vec<String> {506 let data = self.data();507 let Some(secrets) = data.host_secrets.get(host) else {508 return Vec::new();509 };510 secrets.keys().cloned().collect()511 }512513 pub fn has_secret(&self, host: &str, secret: &str) -> bool {514 let data = self.data();515 let Some(host_secrets) = data.host_secrets.get(host) else {516 return false;517 };518 host_secrets.contains_key(secret)519 }520 pub fn insert_secret(&self, host: &str, secret: String, value: FleetSecret) {521 let mut data = self.data_mut();522 let host_secrets = data.host_secrets.entry(host.to_owned()).or_default();523 host_secrets.insert(secret, value);524 }525526 pub fn host_secret(&self, host: &str, secret: &str) -> Result<FleetSecret> {527 let data = self.data();528 let Some(host_secrets) = data.host_secrets.get(host) else {529 bail!("no secrets for machine {host}");530 };531 let Some(secret) = host_secrets.get(secret) else {532 bail!("machine {host} has no secret {secret}");533 };534 Ok(secret.clone())535 }536 pub fn shared_secret(&self, secret: &str) -> Result<FleetSharedSecret> {537 let data = self.data();538 let Some(secret) = data.shared_secrets.get(secret) else {539 bail!("no shared secret {secret}");540 };541 Ok(secret.clone())542 }543 pub async fn shared_secret_expected_owners(&self, secret: &str) -> Result<Vec<String>> {544 let config_field = &self.config_field;545 Ok(nix_go_json!(546 config_field.sharedSecrets[{ secret }].expectedOwners547 ))548 }549550 // TODO: Should this be something modifiable from other processes?551 // E.g terraform provider might want to update FleetData (e.g secrets),552 // and current implementation assumes only one process holds current fleet.nix553 // Given that it is no longer needs to be a file for nix evaluation,554 // maybe it can be a .nix file for persistence, but accessible only555 // thru some shared state controller? Might it be stored in terraform556 // state provider?557 pub fn data(&self) -> MutexGuard<FleetData> {558 self.data.lock().unwrap()559 }560 pub fn data_mut(&self) -> MutexGuard<FleetData> {561 self.data.lock().unwrap()562 }563 pub fn save(&self) -> Result<()> {564 let mut tempfile = NamedTempFile::new_in(self.directory.clone()).context("failed to create updated version of fleet.nix in the same directory as original.\nDo you have write access to it? Access only to the fleet.nix won't be enough, the directory is used for atomic overwrite operation.\nIt is not recommended to use fleet by root anyway, move fleet project to your home directory.")?;565 let data = nixlike::serialize(&self.data() as &FleetData)?;566 tempfile.write_all(567 format!(568 "# This file contains fleet state and shouldn't be edited by hand\n\n{}\n\n# vim: ts=2 et nowrap\n",569 data570 )571 .as_bytes(),572 )?;573 let mut fleet_data_path = self.directory.clone();574 fleet_data_path.push("fleet.nix");575 tempfile.persist(fleet_data_path)?;576 Ok(())577 }578}crates/fleet-base/src/opts.rsdiffbeforeafterboth--- a/crates/fleet-base/src/opts.rs
+++ b/crates/fleet-base/src/opts.rs
@@ -6,7 +6,7 @@
sync::{Arc, Mutex},
};
-use anyhow::{Context, Result};
+use anyhow::{bail, Context, Result};
use clap::Parser;
use nix_eval::{nix_go, util::assert_warn, NixSessionPool, Value};
use nom::{
@@ -182,7 +182,23 @@
// TODO: Config should be detached from opts.
pub async fn build(&self, nix_args: Vec<OsString>, assert: bool) -> Result<Config> {
- let directory = current_dir()?;
+ let cwd = current_dir()?;
+ let mut directory = cwd.clone();
+ let mut fleet_data_path = directory.join("fleet.nix");
+ while !fleet_data_path.is_file() {
+ // fleet.nix
+ fleet_data_path.pop();
+ if !directory.pop() || !fleet_data_path.pop() {
+ bail!(
+ "fleet.nix not found at {} or any of the parent directories",
+ cwd.display()
+ );
+ }
+ fleet_data_path.push("fleet.nix");
+ }
+ let bytes =
+ std::fs::read_to_string(&fleet_data_path).context("reading fleet state (fleet.nix)")?;
+ let data: Mutex<FleetData> = nixlike::parse_str(&bytes)?;
let pool = NixSessionPool::new(
directory.as_os_str().to_owned(),
@@ -193,12 +209,6 @@
let nix_session = pool.get().await?;
let builtins_field = Value::binding(nix_session.clone(), "builtins").await?;
-
- let mut fleet_data_path = directory.clone();
- fleet_data_path.push("fleet.nix");
- let bytes =
- std::fs::read_to_string(fleet_data_path).context("reading fleet state (fleet.nix)")?;
- let data: Mutex<FleetData> = nixlike::parse_str(&bytes)?;
let fleet_root = Value::binding(nix_session.clone(), "fleetConfigurations").await?;
let fleet_field = nix_go!(fleet_root.default({ data }));