hakurei/cmd/hpkg/with.go

package main

import (
	"context"
	"os"
	"strings"

	"hakurei.app/container/check"
	"hakurei.app/container/fhs"
	"hakurei.app/hst"
	"hakurei.app/message"
)

func withNixDaemon(
	ctx context.Context,
	msg message.Msg,
	action string, command []string, net bool, updateConfig func(config *hst.Config) *hst.Config,
	app *appInfo, pathSet *appPathSet, dropShell bool, beforeFail func(),
) {
	flags := hst.FMultiarch | hst.FUserns // nix sandbox requires userns
	if net {
		flags |= hst.FHostNet
	}
	if dropShell {
		flags |= hst.FTty
	}

	mustRunAppDropShell(ctx, msg, updateConfig(&hst.Config{
		ID: app.ID,

		ExtraPerms: []hst.ExtraPermConfig{
			{Path: dataHome, Execute: true},
			{Ensure: true, Path: pathSet.baseDir, Read: true, Write: true, Execute: true},
		},

		Identity: app.Identity,

		Container: &hst.ContainerConfig{
			Hostname: formatHostname(app.Name) + "-" + action,

			Filesystem: []hst.FilesystemConfigJSON{
				{FilesystemConfig: &hst.FSBind{Target: fhs.AbsEtc, Source: pathSet.cacheDir.Append("etc"), Special: true}},
				{FilesystemConfig: &hst.FSBind{Source: pathSet.nixPath, Target: pathNix, Write: true}},
				{FilesystemConfig: &hst.FSLink{Target: pathCurrentSystem, Linkname: app.CurrentSystem.String()}},
				{FilesystemConfig: &hst.FSLink{Target: pathBin, Linkname: pathSwBin.String()}},
				{FilesystemConfig: &hst.FSLink{Target: fhs.AbsUsrBin, Linkname: pathSwBin.String()}},
				{FilesystemConfig: &hst.FSBind{Target: pathDataData.Append(app.ID), Source: pathSet.homeDir, Write: true, Ensure: true}},
			},

			Username: "hakurei",
			Shell:    pathShell,
			Home:     pathDataData.Append(app.ID),

			Path: pathShell,
			Args: []string{bash, "-lc", "rm -f /nix/var/nix/daemon-socket/socket && " +
				// start nix-daemon
				"nix-daemon --store / & " +
				// wait for socket to appear
				"(while [ ! -S /nix/var/nix/daemon-socket/socket ]; do sleep 0.01; done) && " +
				// create directory so nix stops complaining
				"mkdir -p /nix/var/nix/profiles/per-user/root/channels && " +
				strings.Join(command, " && ") +
				// terminate nix-daemon
				" && pkill nix-daemon",
			},

			Flags: flags,
		},
	}), dropShell, beforeFail)
}

func withCacheDir(
	ctx context.Context,
	msg message.Msg,
	action string, command []string, workDir *check.Absolute,
	app *appInfo, pathSet *appPathSet, dropShell bool, beforeFail func(),
) {
	flags := hst.FMultiarch
	if dropShell {
		flags |= hst.FTty
	}

	mustRunAppDropShell(ctx, msg, &hst.Config{
		ID: app.ID,

		ExtraPerms: []hst.ExtraPermConfig{
			{Path: dataHome, Execute: true},
			{Ensure: true, Path: pathSet.baseDir, Read: true, Write: true, Execute: true},
			{Path: workDir, Execute: true},
		},

		Identity: app.Identity,

		Container: &hst.ContainerConfig{
			Hostname: formatHostname(app.Name) + "-" + action,

			Filesystem: []hst.FilesystemConfigJSON{
				{FilesystemConfig: &hst.FSBind{Target: fhs.AbsEtc, Source: workDir.Append(fhs.Etc), Special: true}},
				{FilesystemConfig: &hst.FSBind{Source: workDir.Append("nix"), Target: pathNix}},
				{FilesystemConfig: &hst.FSLink{Target: pathCurrentSystem, Linkname: app.CurrentSystem.String()}},
				{FilesystemConfig: &hst.FSLink{Target: pathBin, Linkname: pathSwBin.String()}},
				{FilesystemConfig: &hst.FSLink{Target: fhs.AbsUsrBin, Linkname: pathSwBin.String()}},
				{FilesystemConfig: &hst.FSBind{Source: workDir, Target: hst.AbsPrivateTmp.Append("bundle")}},
				{FilesystemConfig: &hst.FSBind{Target: pathDataData.Append(app.ID, "cache"), Source: pathSet.cacheDir, Write: true, Ensure: true}},
			},

			Username: "nixos",
			Shell:    pathShell,
			Home:     pathDataData.Append(app.ID, "cache"),

			Path: pathShell,
			Args: []string{bash, "-lc", strings.Join(command, " && ")},

			Flags: flags,
		},
	}, dropShell, beforeFail)
}

func mustRunAppDropShell(ctx context.Context, msg message.Msg, config *hst.Config, dropShell bool, beforeFail func()) {
	if dropShell {
		if config.Container != nil {
			config.Container.Args = []string{bash, "-l"}
		}
		mustRunApp(ctx, msg, config, beforeFail)
		beforeFail()
		msg.BeforeExit()
		os.Exit(0)
	}
	mustRunApp(ctx, msg, config, beforeFail)
}