podman

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//go:build !remote && systemd
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package libpod
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import (
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	"context"
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	"fmt"
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	"os"
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	"os/exec"
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	"strings"
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	systemdCommon "github.com/containers/common/pkg/systemd"
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	"github.com/containers/podman/v5/pkg/errorhandling"
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	"github.com/containers/podman/v5/pkg/rootless"
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	"github.com/containers/podman/v5/pkg/systemd"
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	"github.com/sirupsen/logrus"
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)
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// createTimer systemd timers for healthchecks of a container
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func (c *Container) createTimer(interval string, isStartup bool) error {
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	if c.disableHealthCheckSystemd(isStartup) {
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		return nil
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	}
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	podman, err := os.Executable()
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	if err != nil {
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		return fmt.Errorf("failed to get path for podman for a health check timer: %w", err)
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	}
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	var cmd = []string{"--property", "LogLevelMax=notice"}
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	if rootless.IsRootless() {
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		cmd = append(cmd, "--user")
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	}
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	path := os.Getenv("PATH")
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	if path != "" {
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		cmd = append(cmd, "--setenv=PATH="+path)
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	}
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	cmd = append(cmd, "--unit", c.hcUnitName(isStartup), fmt.Sprintf("--on-unit-inactive=%s", interval), "--timer-property=AccuracySec=1s", podman)
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	if logrus.IsLevelEnabled(logrus.DebugLevel) {
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		cmd = append(cmd, "--log-level=debug", "--syslog")
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	}
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	cmd = append(cmd, "healthcheck", "run", c.ID())
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	conn, err := systemd.ConnectToDBUS()
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	if err != nil {
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		return fmt.Errorf("unable to get systemd connection to add healthchecks: %w", err)
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	}
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	conn.Close()
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	logrus.Debugf("creating systemd-transient files: %s %s", "systemd-run", cmd)
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	systemdRun := exec.Command("systemd-run", cmd...)
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	if output, err := systemdRun.CombinedOutput(); err != nil {
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		return fmt.Errorf("%s", output)
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	}
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	return nil
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}
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// Wait for a message on the channel.  Throw an error if the message is not "done".
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func systemdOpSuccessful(c chan string) error {
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	msg := <-c
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	switch msg {
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	case "done":
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		return nil
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	default:
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		return fmt.Errorf("expected %q but received %q", "done", msg)
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	}
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}
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// startTimer starts a systemd timer for the healthchecks
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func (c *Container) startTimer(isStartup bool) error {
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	if c.disableHealthCheckSystemd(isStartup) {
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		return nil
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	}
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	conn, err := systemd.ConnectToDBUS()
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	if err != nil {
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		return fmt.Errorf("unable to get systemd connection to start healthchecks: %w", err)
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	}
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	defer conn.Close()
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	startFile := fmt.Sprintf("%s.service", c.hcUnitName(isStartup))
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	startChan := make(chan string)
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	if _, err := conn.RestartUnitContext(context.Background(), startFile, "fail", startChan); err != nil {
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		return err
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	}
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	if err := systemdOpSuccessful(startChan); err != nil {
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		return fmt.Errorf("starting systemd health-check timer %q: %w", startFile, err)
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	}
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	return nil
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}
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// removeTransientFiles removes the systemd timer and unit files
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// for the container
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func (c *Container) removeTransientFiles(ctx context.Context, isStartup bool) error {
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	if c.disableHealthCheckSystemd(isStartup) {
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		return nil
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	}
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	conn, err := systemd.ConnectToDBUS()
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	if err != nil {
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		return fmt.Errorf("unable to get systemd connection to remove healthchecks: %w", err)
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	}
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	defer conn.Close()
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	// Errors are returned at the very end. Let's make sure to stop and
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	// clean up as much as possible.
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	stopErrors := []error{}
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	// Stop the timer before the service to make sure the timer does not
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	// fire after the service is stopped.
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	timerChan := make(chan string)
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	timerFile := fmt.Sprintf("%s.timer", c.hcUnitName(isStartup))
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	if _, err := conn.StopUnitContext(ctx, timerFile, "ignore-dependencies", timerChan); err != nil {
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		if !strings.HasSuffix(err.Error(), ".timer not loaded.") {
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			stopErrors = append(stopErrors, fmt.Errorf("removing health-check timer %q: %w", timerFile, err))
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		}
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	} else if err := systemdOpSuccessful(timerChan); err != nil {
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		stopErrors = append(stopErrors, fmt.Errorf("stopping systemd health-check timer %q: %w", timerFile, err))
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	}
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	// Reset the service before stopping it to make sure it's being removed
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	// on stop.
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	serviceChan := make(chan string)
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	serviceFile := fmt.Sprintf("%s.service", c.hcUnitName(isStartup))
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	if err := conn.ResetFailedUnitContext(ctx, serviceFile); err != nil {
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		logrus.Debugf("Failed to reset unit file: %q", err)
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	}
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	if _, err := conn.StopUnitContext(ctx, serviceFile, "ignore-dependencies", serviceChan); err != nil {
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		if !strings.HasSuffix(err.Error(), ".service not loaded.") {
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			stopErrors = append(stopErrors, fmt.Errorf("removing health-check service %q: %w", serviceFile, err))
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		}
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	} else if err := systemdOpSuccessful(serviceChan); err != nil {
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		stopErrors = append(stopErrors, fmt.Errorf("stopping systemd health-check service %q: %w", serviceFile, err))
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	}
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	return errorhandling.JoinErrors(stopErrors)
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}
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func (c *Container) disableHealthCheckSystemd(isStartup bool) bool {
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	if !systemdCommon.RunsOnSystemd() || os.Getenv("DISABLE_HC_SYSTEMD") == "true" {
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		return true
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	}
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	if isStartup {
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		if c.config.StartupHealthCheckConfig.Interval == 0 {
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			return true
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		}
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	}
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	if c.config.HealthCheckConfig.Interval == 0 {
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		return true
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	}
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	return false
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}
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// Systemd unit name for the healthcheck systemd unit
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func (c *Container) hcUnitName(isStartup bool) string {
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	unitName := c.ID()
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	if isStartup {
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		unitName += "-startup"
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	}
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	return unitName
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}
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