feat: backend container executor implement

2026-08-15 20:58:01 +08:00
parent b4e18c6f0c
commit fbce91d797
10 changed files with 1662 additions and 1 deletions
@@ -0,0 +1,150 @@
+package healthcheck
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"time"
+)
+
+const maximumResponseBytes = 1 << 20
+
+var ErrWorkloadStopped = errors.New("workload stopped before becoming healthy")
+
+// RunningProbe 在每次健康采样前核对容器是否仍处于运行状态。
+type RunningProbe func(context.Context) (bool, error)
+
+// ActuatorReport 是一次成功健康采样的非敏感摘要。
+type ActuatorReport struct {
+	Status     string
+	Components map[string]string
+}
+
+// ActuatorChecker 等待 Spring Boot Actuator 顶层状态进入 UP。
+// 它只采样健康状态，不负责重启容器。
+type ActuatorChecker struct {
+	client   *http.Client
+	interval time.Duration
+}
+
+// Check 执行一次健康采样，供事务恢复时核对已经记录意图的健康步骤。
+func (c *ActuatorChecker) Check(ctx context.Context, endpoint string, running RunningProbe) (ActuatorReport, bool, error) {
+	if running == nil {
+		return ActuatorReport{}, false, errors.New("running probe is required")
+	}
+	if err := validateEndpoint(endpoint); err != nil {
+		return ActuatorReport{}, false, err
+	}
+	return c.sample(ctx, endpoint, running)
+}
+
+// NewActuatorChecker 创建固定间隔的 Actuator 检查器。
+func NewActuatorChecker(client *http.Client, interval time.Duration) (*ActuatorChecker, error) {
+	if client == nil {
+		return nil, errors.New("HTTP client is required")
+	}
+	if interval <= 0 {
+		return nil, errors.New("health check interval must be positive")
+	}
+	return &ActuatorChecker{client: client, interval: interval}, nil
+}
+
+// Wait 在 timeout 范围内持续采样。容器停止时立即失败；其他未就绪结果保留到截止时间。
+func (c *ActuatorChecker) Wait(ctx context.Context, endpoint string, timeout time.Duration, running RunningProbe) (ActuatorReport, error) {
+	if timeout <= 0 {
+		return ActuatorReport{}, errors.New("health check timeout must be positive")
+	}
+	if running == nil {
+		return ActuatorReport{}, errors.New("running probe is required")
+	}
+	if err := validateEndpoint(endpoint); err != nil {
+		return ActuatorReport{}, err
+	}
+
+	waitContext, cancel := context.WithTimeout(ctx, timeout)
+	defer cancel()
+	var lastErr error
+	for {
+		report, ready, err := c.sample(waitContext, endpoint, running)
+		if ready {
+			return report, nil
+		}
+		if errors.Is(err, ErrWorkloadStopped) {
+			return ActuatorReport{}, err
+		}
+		lastErr = err
+
+		timer := time.NewTimer(c.interval)
+		select {
+		case <-waitContext.Done():
+			timer.Stop()
+			return ActuatorReport{}, fmt.Errorf("Actuator did not become UP within %s: %w", timeout, errors.Join(waitContext.Err(), lastErr))
+		case <-timer.C:
+		}
+	}
+}
+
+func validateEndpoint(endpoint string) error {
+	parsed, err := url.ParseRequestURI(endpoint)
+	if err != nil || parsed.Scheme != "http" || parsed.Host == "" {
+		return fmt.Errorf("invalid Actuator HTTP endpoint: %q", endpoint)
+	}
+	return nil
+}
+
+func (c *ActuatorChecker) sample(ctx context.Context, endpoint string, running RunningProbe) (ActuatorReport, bool, error) {
+	isRunning, err := running(ctx)
+	if err != nil {
+		return ActuatorReport{}, false, fmt.Errorf("inspect workload before health check: %w", err)
+	}
+	if !isRunning {
+		return ActuatorReport{}, false, ErrWorkloadStopped
+	}
+
+	request, err := http.NewRequestWithContext(ctx, http.MethodGet, endpoint, nil)
+	if err != nil {
+		return ActuatorReport{}, false, fmt.Errorf("create Actuator request: %w", err)
+	}
+	request.Header.Set("Accept", "application/json")
+	response, err := c.client.Do(request)
+	if err != nil {
+		return ActuatorReport{}, false, fmt.Errorf("request Actuator health: %w", err)
+	}
+	defer response.Body.Close()
+	body, err := io.ReadAll(io.LimitReader(response.Body, maximumResponseBytes+1))
+	if err != nil {
+		return ActuatorReport{}, false, fmt.Errorf("read Actuator response: %w", err)
+	}
+	if len(body) > maximumResponseBytes {
+		return ActuatorReport{}, false, errors.New("Actuator response exceeds size limit")
+	}
+	if response.StatusCode != http.StatusOK {
+		return ActuatorReport{}, false, fmt.Errorf("Actuator returned HTTP status %d", response.StatusCode)
+	}
+
+	var payload actuatorPayload
+	if err := json.Unmarshal(body, &payload); err != nil {
+		return ActuatorReport{}, false, fmt.Errorf("decode Actuator response: %w", err)
+	}
+	report := ActuatorReport{Status: payload.Status, Components: make(map[string]string, len(payload.Components))}
+	for name, component := range payload.Components {
+		report.Components[name] = component.Status
+	}
+	if payload.Status != "UP" {
+		return report, false, fmt.Errorf("Actuator status is %q", payload.Status)
+	}
+	return report, true, nil
+}
+
+type actuatorPayload struct {
+	Status     string                       `json:"status"`
+	Components map[string]actuatorComponent `json:"components"`
+}
+
+type actuatorComponent struct {
+	Status string `json:"status"`
+}