Support VM export

codchi/src/cli.rs

@@ -476,7 +476,7 @@ See the following docs on how to register the completions with your shell:
     #[clap(hide = true)]
     Tray {},
 
-    #[clap(about = "Export the file system of a code machine.")]
+    #[clap(about = "Export the file system of a code machine including NixOS configuration and codchi secrets.")]
     Tar {
         /// Name of the code machine
         name: String,

codchi/src/config/flake.rs

@@ -1,6 +1,6 @@
 use super::*;
 use crate::cli::ModuleAttrPath;
-use crate::consts::{store, ToPath};
+use crate::consts::ToPath;
 use crate::util::*;
 use git_url_parse::{GitUrl, Scheme};
 use std::marker::PhantomData;
@@ -44,7 +44,7 @@ fn metadata_to_query(metadata: &[(&str, Option<&String>)]) -> String {
 
 impl<W: Hkd> FlakeUrl<W> {
     /// Serialize to nix readable flake url, ignoring `flake_module` (the part after '#')
-    pub fn to_nix_url(&self, machine_name: &str) -> String {
+    pub fn to_nix_url(&self, local_root: LinuxPath) -> String {
         use FlakeLocation::*;
         use FlakeScheme::*;
 
@@ -75,7 +75,7 @@ impl<W: Hkd> FlakeUrl<W> {
                 }
             }
             Local { path } => {
-                let real_path = store::DIR_DATA.join_machine(machine_name).join_str(path).0;
+                let real_path = local_root.join_str(path).0;
                 let query = metadata_to_query(&[
                     ("commit", self.commit.as_ref()),
                     ("ref", self.r#ref.as_ref()),
@@ -302,6 +302,7 @@ pub enum FlakeScheme {
 
 #[cfg(test)]
 mod tests {
+    use crate::consts;
     use super::*;
 
     fn local() -> FlakeUrl<Required> {
@@ -357,15 +358,15 @@ mod tests {
     #[test]
     fn to_nix_url() {
         assert_eq!(
-            local().to_nix_url("machine_name"),
+            local().to_nix_url(consts::store::DIR_DATA.join_machine("machine_name")),
             "git+file:///data/machine/machine_name/docs/codchi?"
         );
         assert_eq!(
-            remote_gh().to_nix_url(""),
+            remote_gh().to_nix_url(LinuxPath("".to_string())),
             "github:aformatik/codchi?host=github.com"
         );
         assert_eq!(
-            remote_custom().to_nix_url(""),
+            remote_custom().to_nix_url(LinuxPath("".to_string())),
             "git+https://my:[email protected]/aformatik/codchi.git?commit=jakfkl2&ref=my-branch&host=foo.bar"
         );
     }

codchi/src/module.rs

@@ -2,6 +2,7 @@ use crate::cli::{InputOptions, ModuleAttrPath, ModuleName, NixpkgsLocation, Rela
 use crate::config::git_url::{GitUrl, Scheme};
 use crate::consts;
 use crate::consts::user::DEFAULT_HOME;
+use crate::consts::ToPath;
 use crate::logging::{log_progress, set_progress_status};
 use crate::platform::{nix::NixDriver, *};
 use crate::progress_scope;
@@ -309,7 +310,7 @@ pub fn fetch_modules(
         .unwrap_or_else(|| petname(1, "-").expect("Failed to generate random name"));
 
     let flake_url = inquire_module_url(opts, url, allow_local)?;
-    let nix_url = flake_url.to_nix_url(&machine.name);
+    let nix_url = flake_url.to_nix_url(consts::store::DIR_DATA.join_machine(&machine.name));
 
     let available_modules = progress_scope! {
         set_progress_status("Fetching available modules...");

codchi/src/platform/linux/lxd.rs

@@ -6,25 +6,22 @@ use std::process::Command;
 use std::sync::OnceLock;
 use which::which;
 
-static LXD_COMMAND: OnceLock<&str> = OnceLock::new();
-
-pub fn init_lxc_command() -> Result<()> {
-    LXD_COMMAND.get_or_try_init(|| {
-        if let Ok(_) = which("lxd") {
-            log::trace!("Using LXD as container runtime.");
-            Ok("lxc")
-        } else if let Ok(_) = which("incus") {
-            log::trace!("Using Incus as container runtime.");
-            Ok("incus")
-        } else {
-            bail!("Either LXD or Incus is required to run Codchi.")
-        }
-    })?;
-    Ok(())
-}
-
 pub fn lxc_command(args: &[&str]) -> Command {
-    let mut cmd = Command::new(LXD_COMMAND.get().expect("init_lxc_command was not called"));
+    static LXD_COMMAND: OnceLock<&str> = OnceLock::new();
+    let command = LXD_COMMAND
+        .get_or_try_init(|| {
+            if let Ok(_) = which("lxd") {
+                log::trace!("Using LXD as container runtime.");
+                Ok("lxc")
+            } else if let Ok(_) = which("incus") {
+                log::trace!("Using Incus as container runtime.");
+                Ok("incus")
+            } else {
+                bail!("Either LXD or Incus is required to run Codchi.")
+            }
+        })
+        .unwrap();
+    let mut cmd = Command::new(command);
     cmd.arg("-q");
     cmd.args(args);
     cmd

codchi/src/platform/linux/mod.rs

@@ -17,14 +17,7 @@ use inquire::Confirm;
 use log::*;
 use lxd::lxc_command;
 use std::{
-    collections::HashMap,
-    env,
-    fs::{self, File},
-    io::Write,
-    path::PathBuf,
-    process::Command,
-    sync::mpsc::channel,
-    thread,
+    collections::HashMap, env, fs, path::PathBuf, process::Command, sync::mpsc::channel, thread,
 };
 
 pub const NIX_STORE_PACKAGE: &str = "store-lxd";
@@ -34,7 +27,6 @@ pub struct StoreImpl {}
 
 impl Store for StoreImpl {
     fn start_or_init_container() -> Result<Self> {
-        lxd::init_lxc_command()?;
         let status = lxd::container::get_platform_status(consts::CONTAINER_STORE_NAME).context(
             "Failed to run LXD. It seems like LXD is not installed or set up correctly! \
 Please see <https://codchi.dev/introduction/installation#linux> for setup instructions!",
@@ -232,23 +224,7 @@ impl MachineDriver for Machine {
                 )?;
             }
             with_tmp_file(&format!("codchi-{}-env", self.config.name), |path| {
-                let mut env = self.config.secrets.clone();
-
-                env.insert(
-                    "DEBUG".to_string(),
-                    if *DEBUG { "1" } else { "" }.to_string(),
-                );
-                env.insert("MACHINE_NAME".to_string(), self.config.name.clone());
-
-                let mut env_file = File::options()
-                    .write(true)
-                    .create(true)
-                    .truncate(true)
-                    .open(path)?;
-                for (key, value) in env {
-                    writeln!(env_file, r#"export CODCHI_{key}="{value}""#)?;
-                }
-                env_file.sync_all()?;
+                self.write_env_file(&path)?;
                 lxd::container::file_push(
                     &machine_name(&self.config.name),
                     path,
@@ -380,14 +356,61 @@ Is it okay to use {sudo_name}? [y/n]",
 
         with_tmp_file(&format!("codchi-backup-{}", self.config.name), |tmp_dir| {
             fs::create_dir_all(tmp_dir)?;
+
+            let etc_nixos = tmp_dir.join("backup/container/rootfs/etc/nixos");
+            etc_nixos.get_or_create()?;
+            self.write_flake_standalone(etc_nixos.join("flake.nix"))?;
+            fs::copy(
+                consts::host::DIR_CONFIG
+                    .join_machine(&self.config.name)
+                    .join("flake.lock"),
+                etc_nixos.join("flake.lock"),
+            )
+            .trace_err("Failed copying flake.lock")
+            .ignore();
+
+            self.write_env_file(tmp_dir.join(format!(
+                "backup/container/rootfs{}",
+                consts::machine::CODCHI_ENV.0
+            )))?;
+
             let lxc_export = tmp_dir.join("lxc_export.tar").display().to_string();
             let target_file = target_file.display().to_string();
             lxd::container::export(
                 &consts::machine::machine_name(&self.config.name),
                 &lxc_export,
             )?;
             Command::new("tar")
-                .args(["-C", &tmp_dir.display().to_string(), "-xf", &lxc_export])
+                .args([
+                    "-C",
+                    &tmp_dir.display().to_string(),
+                    "-xf",
+                    &lxc_export,
+                    "--exclude=.files",
+                    "--exclude=bin*",
+                    "--exclude=dev*",
+                    "--exclude=etc*",
+                    "--exclude=lib*",
+                    "--exclude=lib64*",
+                    "--exclude=nix*",
+                    "--exclude=proc*",
+                    "--exclude=run*",
+                    "--exclude=sbin*",
+                    "--exclude=sys*",
+                    "--exclude=tmp*",
+                    "--exclude=var/.updated",
+                    "--exclude=var/cache",
+                    "--exclude=var/db*",
+                    "--exclude=var/empty",
+                    "--exclude=var/lib/nixos*",
+                    "--exclude=var/lib/systemd*",
+                    "--exclude=var/lock",
+                    "--exclude=var/log*",
+                    "--exclude=var/spool*",
+                ])
+                .wait_ok()?;
+            Command::new("chmod")
+                .args(["755", &tmp_dir.display().to_string()])
                 .wait_ok()?;
             with_suspended_progress(|| {
                 command_with_privileges(

codchi/src/platform/machine.rs

@@ -2,7 +2,7 @@ use super::{
     platform::HostImpl, Host, LinuxCommandBuilder, LinuxCommandTarget, LinuxUser, NixDriver,
 };
 use crate::{
-    cli::CODCHI_DRIVER_MODULE,
+    cli::{CODCHI_DRIVER_MODULE, DEBUG},
     config::{ConfigResult, EnvSecret, FlakeLocation, MachineConfig},
     consts::{self, host, ToPath},
     logging::{hide_progress, log_progress, set_progress_status, with_suspended_progress},
@@ -13,7 +13,14 @@ use crate::{
 use anyhow::{bail, Context, Result};
 use itertools::Itertools;
 use log::Level;
-use std::{collections::HashMap, fs, sync::mpsc::channel, thread};
+use std::{
+    collections::HashMap,
+    fs::{self, File},
+    io::Write,
+    path::Path,
+    sync::mpsc::channel,
+    thread,
+};
 
 pub trait MachineDriver: Sized {
     fn cmd(&self) -> impl LinuxCommandTarget;
@@ -144,7 +151,7 @@ fi
                 .map(|(name, url)| {
                     format!(
                         r#"    "{name}".url = "{}";"#,
-                        url.to_nix_url(&self.config.name)
+                        url.to_nix_url(consts::store::DIR_DATA.join_machine(&self.config.name))
                     )
                 })
                 .join("\n");
@@ -205,6 +212,85 @@ fi
         Ok(())
     }
 
+    pub fn write_flake_standalone<P: AsRef<Path>>(&self, target: P) -> Result<()> {
+        let flake = {
+            let codchi_url = consts::CODCHI_FLAKE_URL;
+            let codchi_driver = CODCHI_DRIVER_MODULE;
+            let module_inputs = self
+                .config
+                .modules
+                .iter()
+                .map(|(name, url)| {
+                    format!(
+                        r#"    "{name}".url = "{}";"#,
+                        url.to_nix_url(consts::user::DEFAULT_HOME.clone())
+                    )
+                })
+                .join("\n");
+            let nix_system = consts::NIX_SYSTEM;
+            let nixpkgs = if let Some(name) = &self.config.nixpkgs_from {
+                format!(r#"inputs."{name}".inputs.nixpkgs"#)
+            } else {
+                "inputs.codchi_driver.inputs.nixpkgs".to_string()
+            };
+            let modules = self
+                .config
+                .modules
+                .iter()
+                .map(|(name, url)| {
+                    format!(
+                        r#"        inputs."{name}".{module_name}"#,
+                        module_name = url.flake_attr
+                    )
+                })
+                .join("\n");
+            format!(
+                r#"{{
+  inputs = {{
+    {codchi_driver}.url = "{codchi_url}";
+{module_inputs}
+  }};
+  outputs = inputs: {{
+    nixosConfigurations.nixos = {nixpkgs}.lib.nixosSystem {{
+      system = "{nix_system}";
+      modules = [
+        {{ 
+             _module.args.inputs.nixpkgs = {nixpkgs}; 
+             codchi.driver.name = "none";
+        }}
+        inputs.{codchi_driver}.nixosModules.default
+{modules}
+      ];
+    }};
+  }};
+}}"#
+            )
+        };
+        fs::write(target, flake)?;
+        Ok(())
+    }
+
+    pub fn write_env_file<P: AsRef<Path>>(&self, target: P) -> Result<()> {
+        let mut env = self.config.secrets.clone();
+
+        env.insert(
+            "DEBUG".to_string(),
+            if *DEBUG { "1" } else { "" }.to_string(),
+        );
+        env.insert("MACHINE_NAME".to_string(), self.config.name.clone());
+
+        let mut env_file = File::options()
+            .write(true)
+            .create(true)
+            .truncate(true)
+            .open(target)?;
+        for (key, value) in env {
+            writeln!(env_file, r#"export CODCHI_{key}="{value}""#)?;
+        }
+        env_file.sync_all()?;
+        Ok(())
+    }
+
     pub fn update_flake(&self) -> Result<()> {
         Driver::store()
             .cmd()
@@ -514,7 +600,6 @@ git add flake.*
             ConfigResult::None => {}
         }
 
-
         let (lock, _) = MachineConfig::open(target_name, true)?;
         let mut new_cfg = self.config.clone();
         new_cfg.name = target_name.to_string();