settings.rs

/*! Configurable knobs and their related errors
*/
use std::{collections::HashMap, path::PathBuf};

#[cfg(feature = "cli")]
use clap::ArgAction;
use url::Url;

pub const SCRATCH_DIR: &str = "/nix/temp-install-dir";

/// Default [`nix_package_url`](CommonSettings::nix_package_url) for Linux x86_64
pub const NIX_X64_64_LINUX_URL: &str =
    "https://releases.nixos.org/nix/nix-2.15.0/nix-2.15.0-x86_64-linux.tar.xz";
/// Default [`nix_package_url`](CommonSettings::nix_package_url) for Linux x86 (32 bit)
pub const NIX_I686_LINUX_URL: &str =
    "https://releases.nixos.org/nix/nix-2.15.0/nix-2.15.0-i686-linux.tar.xz";
/// Default [`nix_package_url`](CommonSettings::nix_package_url) for Linux aarch64
pub const NIX_AARCH64_LINUX_URL: &str =
    "https://releases.nixos.org/nix/nix-2.15.0/nix-2.15.0-aarch64-linux.tar.xz";
/// Default [`nix_package_url`](CommonSettings::nix_package_url) for Darwin x86_64
pub const NIX_X64_64_DARWIN_URL: &str =
    "https://releases.nixos.org/nix/nix-2.15.0/nix-2.15.0-x86_64-darwin.tar.xz";
/// Default [`nix_package_url`](CommonSettings::nix_package_url) for Darwin aarch64
pub const NIX_AARCH64_DARWIN_URL: &str =
    "https://releases.nixos.org/nix/nix-2.15.0/nix-2.15.0-aarch64-darwin.tar.xz";

#[derive(Debug, serde::Deserialize, serde::Serialize, Clone, Copy, PartialEq, Eq)]
#[cfg_attr(feature = "cli", derive(clap::ValueEnum))]
pub enum InitSystem {
    #[cfg(not(target_os = "macos"))]
    None,
    #[cfg(target_os = "linux")]
    Systemd,
    #[cfg(target_os = "macos")]
    Launchd,
}

impl std::fmt::Display for InitSystem {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        match self {
            #[cfg(not(target_os = "macos"))]
            InitSystem::None => write!(f, "none"),
            #[cfg(target_os = "linux")]
            InitSystem::Systemd => write!(f, "systemd"),
            #[cfg(target_os = "macos")]
            InitSystem::Launchd => write!(f, "launchd"),
        }
    }
}

/** Common settings used by all [`BuiltinPlanner`](crate::planner::BuiltinPlanner)s

Settings which only apply to certain [`Planner`](crate::planner::Planner)s should be located in the planner.

*/
#[serde_with::serde_as]
#[derive(Debug, serde::Deserialize, serde::Serialize, Clone)]
#[cfg_attr(feature = "cli", derive(clap::Parser))]
pub struct CommonSettings {
    /// Modify the user profile to automatically load nix
    #[cfg_attr(
        feature = "cli",
        clap(
            action(ArgAction::SetFalse),
            default_value = "true",
            global = true,
            env = "NIX_INSTALLER_MODIFY_PROFILE",
            long = "no-modify-profile"
        )
    )]
    pub modify_profile: bool,

    /// The Nix build group name
    #[cfg_attr(
        feature = "cli",
        clap(
            long,
            default_value = "nixbld",
            env = "NIX_INSTALLER_NIX_BUILD_GROUP_NAME",
            global = true
        )
    )]
    pub nix_build_group_name: String,

    /// The Nix build group GID
    #[cfg_attr(
        feature = "cli",
        clap(
            long,
            default_value_t = 30_000,
            env = "NIX_INSTALLER_NIX_BUILD_GROUP_ID",
            global = true
        )
    )]
    pub nix_build_group_id: u32,

    /// The Nix build user prefix (user numbers will be postfixed)
    #[cfg_attr(
        feature = "cli",
        clap(long, env = "NIX_INSTALLER_NIX_BUILD_USER_PREFIX", global = true)
    )]
    #[cfg_attr(
        all(target_os = "macos", feature = "cli"),
        clap(default_value = "_nixbld")
    )]
    #[cfg_attr(
        all(target_os = "linux", feature = "cli"),
        clap(default_value = "nixbld")
    )]
    pub nix_build_user_prefix: String,

    /// Number of build users to create
    #[cfg_attr(
        all(target_os = "linux", feature = "cli"),
        doc = "On Linux, Nix's `auto-allocate-uids` feature will be enabled, so users don't need to be created."
    )]
    #[cfg_attr(
        feature = "cli",
        clap(
            long,
            alias = "daemon-user-count",
            env = "NIX_INSTALLER_NIX_BUILD_USER_COUNT",
            global = true
        )
    )]
    #[cfg_attr(all(target_os = "macos", feature = "cli"), clap(default_value = "32"))]
    #[cfg_attr(all(target_os = "linux", feature = "cli"), clap(default_value = "0"))]
    pub nix_build_user_count: u32,

    /// The Nix build user base UID (ascending)
    #[cfg_attr(
        feature = "cli",
        clap(long, env = "NIX_INSTALLER_NIX_BUILD_USER_ID_BASE", global = true)
    )]
    #[cfg_attr(
        all(target_os = "macos", feature = "cli"),
        doc = "Service users on Mac should be between 200-400"
    )]
    #[cfg_attr(all(target_os = "macos", feature = "cli"), clap(default_value_t = 300))]
    #[cfg_attr(
        all(target_os = "linux", feature = "cli"),
        clap(default_value_t = 30_000)
    )]
    pub nix_build_user_id_base: u32,

    /// The Nix package URL
    #[cfg_attr(
        feature = "cli",
        clap(long, env = "NIX_INSTALLER_NIX_PACKAGE_URL", global = true)
    )]
    #[cfg_attr(
        all(target_os = "macos", target_arch = "x86_64", feature = "cli"),
        clap(
            default_value = NIX_X64_64_DARWIN_URL,
        )
    )]
    #[cfg_attr(
        all(target_os = "macos", target_arch = "aarch64", feature = "cli"),
        clap(
            default_value = NIX_AARCH64_DARWIN_URL,
        )
    )]
    #[cfg_attr(
        all(target_os = "linux", target_arch = "x86_64", feature = "cli"),
        clap(
            default_value = NIX_X64_64_LINUX_URL,
        )
    )]
    #[cfg_attr(
        all(target_os = "linux", target_arch = "x86", feature = "cli"),
        clap(
            default_value = NIX_I686_LINUX_URL,
        )
    )]
    #[cfg_attr(
        all(target_os = "linux", target_arch = "aarch64", feature = "cli"),
        clap(
            default_value = NIX_AARCH64_LINUX_URL,
        )
    )]
    pub nix_package_url: Url,

    /// The proxy to use (if any), valid proxy bases are `https://$URL`, `http://$URL` and `socks5://$URL`
    #[cfg_attr(feature = "cli", clap(long, env = "NIX_INSTALLER_PROXY"))]
    pub proxy: Option<Url>,

    /// An SSL cert to use (if any), used for fetching Nix and sets `NIX_SSL_CERT_FILE` for Nix
    #[cfg_attr(feature = "cli", clap(long, env = "NIX_INSTALLER_SSL_CERT_FILE"))]
    pub ssl_cert_file: Option<PathBuf>,

    /// Extra configuration lines for `/etc/nix.conf`
    #[cfg_attr(feature = "cli", clap(long, action = ArgAction::Append, num_args = 0.., env = "NIX_INSTALLER_EXTRA_CONF", global = true))]
    pub extra_conf: Vec<String>,

    /// If `nix-installer` should forcibly recreate files it finds existing
    #[cfg_attr(
        feature = "cli",
        clap(
            long,
            action(ArgAction::SetTrue),
            default_value = "false",
            global = true,
            env = "NIX_INSTALLER_FORCE"
        )
    )]
    pub force: bool,

    #[cfg(feature = "diagnostics")]
    /// The URL or file path for an installation diagnostic to be sent
    ///
    /// Sample of the data sent:
    ///
    /// {
    ///     "version": "0.4.0",
    ///     "planner": "linux",
    ///     "configured_settings": [ "modify_profile" ],
    ///     "os_name": "Ubuntu",
    ///     "os_version": "22.04.1 LTS (Jammy Jellyfish)",
    ///     "triple": "x86_64-unknown-linux-gnu",
    ///     "is_ci": false,
    ///     "action": "Install",
    ///     "status": "Success"
    /// }
    ///
    /// To disable diagnostic reporting, unset the default with `--diagnostic-endpoint ""`, or `NIX_INSTALLER_DIAGNOSTIC_ENDPOINT=""`
    #[clap(
        long,
        env = "NIX_INSTALLER_DIAGNOSTIC_ENDPOINT",
        global = true,
        value_parser = crate::diagnostics::diagnostic_endpoint_validator,
        num_args = 0..=1, // Required to allow `--diagnostic-endpoint` or `NIX_INSTALLER_DIAGNOSTIC_ENDPOINT=""`
        default_value = "https://install.determinate.systems/nix/diagnostic"
    )]
    pub diagnostic_endpoint: Option<String>,
}

impl CommonSettings {
    /// The default settings for the given Architecture & Operating System
    pub async fn default() -> Result<Self, InstallSettingsError> {
        let url;
        let nix_build_user_prefix;
        let nix_build_user_id_base;
        let nix_build_user_count;

        use target_lexicon::{Architecture, OperatingSystem};
        match (Architecture::host(), OperatingSystem::host()) {
            #[cfg(target_os = "linux")]
            (Architecture::X86_64, OperatingSystem::Linux) => {
                url = NIX_X64_64_LINUX_URL;
                nix_build_user_prefix = "nixbld";
                nix_build_user_id_base = 30000;
                nix_build_user_count = 0;
            },
            #[cfg(target_os = "linux")]
            (Architecture::X86_32(_), OperatingSystem::Linux) => {
                url = NIX_I686_LINUX_URL;
                nix_build_user_prefix = "nixbld";
                nix_build_user_id_base = 30000;
                nix_build_user_count = 0;
            },
            #[cfg(target_os = "linux")]
            (Architecture::Aarch64(_), OperatingSystem::Linux) => {
                url = NIX_AARCH64_LINUX_URL;
                nix_build_user_prefix = "nixbld";
                nix_build_user_id_base = 30000;
                nix_build_user_count = 0;
            },
            #[cfg(target_os = "macos")]
            (Architecture::X86_64, OperatingSystem::MacOSX { .. })
            | (Architecture::X86_64, OperatingSystem::Darwin) => {
                url = NIX_X64_64_DARWIN_URL;
                nix_build_user_prefix = "_nixbld";
                nix_build_user_id_base = 300;
                nix_build_user_count = 32;
            },
            #[cfg(target_os = "macos")]
            (Architecture::Aarch64(_), OperatingSystem::MacOSX { .. })
            | (Architecture::Aarch64(_), OperatingSystem::Darwin) => {
                url = NIX_AARCH64_DARWIN_URL;
                nix_build_user_prefix = "_nixbld";
                nix_build_user_id_base = 300;
                nix_build_user_count = 32;
            },
            _ => {
                return Err(InstallSettingsError::UnsupportedArchitecture(
                    target_lexicon::HOST,
                ))
            },
        };

        Ok(Self {
            modify_profile: true,
            nix_build_group_name: String::from("nixbld"),
            nix_build_group_id: 30_000,
            nix_build_user_id_base,
            nix_build_user_count,
            nix_build_user_prefix: nix_build_user_prefix.to_string(),
            nix_package_url: url.parse()?,
            proxy: Default::default(),
            extra_conf: Default::default(),
            force: false,
            ssl_cert_file: Default::default(),
            #[cfg(feature = "diagnostics")]
            diagnostic_endpoint: Some("https://install.determinate.systems/nix/diagnostic".into()),
        })
    }

    /// A listing of the settings, suitable for [`Planner::settings`](crate::planner::Planner::settings)
    pub fn settings(&self) -> Result<HashMap<String, serde_json::Value>, InstallSettingsError> {
        let Self {
            modify_profile,
            nix_build_group_name,
            nix_build_group_id,
            nix_build_user_prefix,
            nix_build_user_id_base,
            nix_build_user_count,
            nix_package_url,
            proxy,
            extra_conf,
            force,
            ssl_cert_file,
            #[cfg(feature = "diagnostics")]
            diagnostic_endpoint,
        } = self;
        let mut map = HashMap::default();

        map.insert(
            "modify_profile".into(),
            serde_json::to_value(modify_profile)?,
        );
        map.insert(
            "nix_build_group_name".into(),
            serde_json::to_value(nix_build_group_name)?,
        );
        map.insert(
            "nix_build_group_id".into(),
            serde_json::to_value(nix_build_group_id)?,
        );
        map.insert(
            "nix_build_user_prefix".into(),
            serde_json::to_value(nix_build_user_prefix)?,
        );
        map.insert(
            "nix_build_user_id_base".into(),
            serde_json::to_value(nix_build_user_id_base)?,
        );
        map.insert(
            "nix_build_user_count".into(),
            serde_json::to_value(nix_build_user_count)?,
        );
        map.insert(
            "nix_package_url".into(),
            serde_json::to_value(nix_package_url)?,
        );
        map.insert("proxy".into(), serde_json::to_value(proxy)?);
        map.insert("ssl_cert_file".into(), serde_json::to_value(ssl_cert_file)?);
        map.insert("extra_conf".into(), serde_json::to_value(extra_conf)?);
        map.insert("force".into(), serde_json::to_value(force)?);

        #[cfg(feature = "diagnostics")]
        map.insert(
            "diagnostic_endpoint".into(),
            serde_json::to_value(diagnostic_endpoint)?,
        );

        Ok(map)
    }
}
#[cfg(target_os = "linux")]
async fn linux_detect_systemd_started() -> bool {
    use std::process::Stdio;

    let mut started = false;
    if std::path::Path::new("/run/systemd/system").exists() {
        started = if tokio::process::Command::new("systemctl")
            .arg("status")
            .stdin(Stdio::null())
            .stdout(Stdio::null())
            .stderr(Stdio::null())
            .status()
            .await
            .ok()
            .map(|exit| exit.success())
            .unwrap_or(false)
        {
            true
        } else {
            false
        }
    }

    // TODO: Other inits
    started
}

#[serde_with::serde_as]
#[derive(Debug, serde::Deserialize, serde::Serialize, Clone)]
#[cfg_attr(feature = "cli", derive(clap::Parser))]
pub struct InitSettings {
    /// Which init system to configure (if `--init none` Nix will be root-only)
    #[cfg_attr(feature = "cli", clap(value_parser, long, env = "NIX_INSTALLER_INIT",))]
    #[cfg_attr(
        all(target_os = "macos", feature = "cli"),
        clap(default_value_t = InitSystem::Launchd)
    )]
    #[cfg_attr(
        all(target_os = "linux", feature = "cli"),
        clap(default_value_t = InitSystem::Systemd)
    )]
    pub init: InitSystem,

    /// Start the daemon (if not `--init none`)
    #[cfg_attr(
        feature = "cli",
        clap(
            value_parser,
            long,
            action(ArgAction::SetFalse),
            env = "NIX_INSTALLER_START_DAEMON",
            default_value_t = true,
            long = "no-start-daemon"
        )
    )]
    pub start_daemon: bool,
}

impl InitSettings {
    /// The default settings for the given Architecture & Operating System
    pub async fn default() -> Result<Self, InstallSettingsError> {
        use target_lexicon::{Architecture, OperatingSystem};
        let (init, start_daemon) = match (Architecture::host(), OperatingSystem::host()) {
            #[cfg(target_os = "linux")]
            (Architecture::X86_64, OperatingSystem::Linux) => {
                (InitSystem::Systemd, linux_detect_systemd_started().await)
            },
            #[cfg(target_os = "linux")]
            (Architecture::X86_32(_), OperatingSystem::Linux) => {
                (InitSystem::Systemd, linux_detect_systemd_started().await)
            },
            #[cfg(target_os = "linux")]
            (Architecture::Aarch64(_), OperatingSystem::Linux) => {
                (InitSystem::Systemd, linux_detect_systemd_started().await)
            },
            #[cfg(target_os = "macos")]
            (Architecture::X86_64, OperatingSystem::MacOSX { .. })
            | (Architecture::X86_64, OperatingSystem::Darwin) => (InitSystem::Launchd, true),
            #[cfg(target_os = "macos")]
            (Architecture::Aarch64(_), OperatingSystem::MacOSX { .. })
            | (Architecture::Aarch64(_), OperatingSystem::Darwin) => (InitSystem::Launchd, true),
            _ => {
                return Err(InstallSettingsError::UnsupportedArchitecture(
                    target_lexicon::HOST,
                ))
            },
        };

        Ok(Self { init, start_daemon })
    }

    /// A listing of the settings, suitable for [`Planner::settings`](crate::planner::Planner::settings)
    pub fn settings(&self) -> Result<HashMap<String, serde_json::Value>, InstallSettingsError> {
        let Self { init, start_daemon } = self;
        let mut map = HashMap::default();

        map.insert("init".into(), serde_json::to_value(init)?);
        map.insert("start_daemon".into(), serde_json::to_value(start_daemon)?);
        Ok(map)
    }

    /// Which init system to configure
    pub fn init(&mut self, init: InitSystem) -> &mut Self {
        self.init = init;
        self
    }

    /// Start the daemon (if one is configured)
    pub fn start_daemon(&mut self, toggle: bool) -> &mut Self {
        self.start_daemon = toggle;
        self
    }
}

/// An error originating from a [`Planner::settings`](crate::planner::Planner::settings)
#[non_exhaustive]
#[derive(thiserror::Error, Debug, strum::IntoStaticStr)]
pub enum InstallSettingsError {
    /// `nix-installer` does not support the architecture right now
    #[error("`nix-installer` does not support the `{0}` architecture right now")]
    UnsupportedArchitecture(target_lexicon::Triple),
    /// Parsing URL
    #[error("Parsing URL")]
    Parse(
        #[source]
        #[from]
        url::ParseError,
    ),
    /// JSON serialization or deserialization error
    #[error("JSON serialization or deserialization error")]
    SerdeJson(
        #[source]
        #[from]
        serde_json::Error,
    ),
    #[error("No supported init system found")]
    InitNotSupported,
}

#[cfg(feature = "diagnostics")]
impl crate::diagnostics::ErrorDiagnostic for InstallSettingsError {
    fn diagnostic(&self) -> String {
        let static_str: &'static str = (self).into();
        return static_str.to_string();
    }
}