refactor(api): simplify handler structure

Author: pixel365

internal/api/config.go

@@ -0,0 +1,67 @@
+package api
+
+import (
+	"fmt"
+	"net/http"
+
+	"github.com/pixel365/pulse/internal/config"
+)
+
+func (h *Handler) ensureService(serviceID string) error {
+	if _, ok := h.cfgProvider.Current().Services[serviceID]; ok {
+		return nil
+	}
+
+	return apiError{
+		status: http.StatusNotFound,
+		err:    fmt.Errorf("service %s not found", serviceID),
+	}
+}
+
+func (h *Handler) ensureCheck(serviceID, checkID string) error {
+	_, err := h.checkFields(serviceID, checkID)
+	return err
+}
+
+func (h *Handler) checkFields(serviceID, checkID string) (config.CheckFields, error) {
+	cfg := h.cfgProvider.Current()
+
+	if fields, ok := checkFields(cfg.HttpChecks, serviceID, checkID); ok {
+		return fields, nil
+	}
+
+	if fields, ok := checkFields(cfg.TCPChecks, serviceID, checkID); ok {
+		return fields, nil
+	}
+
+	if fields, ok := checkFields(cfg.GRPCChecks, serviceID, checkID); ok {
+		return fields, nil
+	}
+
+	if fields, ok := checkFields(cfg.DNSChecks, serviceID, checkID); ok {
+		return fields, nil
+	}
+
+	if fields, ok := checkFields(cfg.TLSChecks, serviceID, checkID); ok {
+		return fields, nil
+	}
+
+	return config.CheckFields{}, apiError{
+		status: http.StatusNotFound,
+		err:    fmt.Errorf("check %s/%s not found", serviceID, checkID),
+	}
+}
+
+func checkFields[T any](
+	checks map[string]config.TypedCheck[T],
+	serviceID string,
+	checkID string,
+) (config.CheckFields, bool) {
+	for i := range checks {
+		if checks[i].Service == serviceID && checks[i].ID == checkID {
+			return checks[i].CheckFields, true
+		}
+	}
+
+	return config.CheckFields{}, false
+}

internal/api/errors.go

@@ -0,0 +1,33 @@
+package api
+
+import (
+	"errors"
+	"net/http"
+
+	"github.com/go-chi/render"
+)
+
+type apiError struct {
+	err    error
+	status int
+}
+
+func (e apiError) Error() string {
+	return e.err.Error()
+}
+
+func statusCode(err error, fallback int) int {
+	var apiErr apiError
+	if ok := errors.As(err, &apiErr); ok {
+		return apiErr.status
+	}
+
+	return fallback
+}
+
+func errorResponse(w http.ResponseWriter, r *http.Request, status int, err error) {
+	render.Status(r, status)
+	render.JSON(w, r, map[string]string{
+		"error": err.Error(),
+	})
+}

internal/api/filters.go

@@ -0,0 +1,124 @@
+package api
+
+import (
+	"fmt"
+	"net/http"
+	"strconv"
+	"time"
+
+	"github.com/go-chi/chi/v5"
+
+	"github.com/pixel365/pulse/internal/model"
+)
+
+func executionFilterFromRequest(r *http.Request) (model.CheckExecutionFilter, error) {
+	filter := model.CheckExecutionFilter{
+		ServiceID: chi.URLParam(r, "serviceId"),
+		CheckID:   chi.URLParam(r, "checkId"),
+	}
+
+	query := r.URL.Query()
+
+	if raw := query.Get("from"); raw != "" {
+		from, err := time.Parse(time.RFC3339, raw)
+		if err != nil {
+			return filter, err
+		}
+		filter.From = &from
+	}
+
+	if raw := query.Get("to"); raw != "" {
+		to, err := time.Parse(time.RFC3339, raw)
+		if err != nil {
+			return filter, err
+		}
+		filter.To = &to
+	}
+
+	if raw := query.Get("limit"); raw != "" {
+		limit, err := strconv.Atoi(raw)
+		if err != nil {
+			return filter, err
+		}
+		filter.Limit = limit
+	}
+
+	return filter, nil
+}
+
+func (h *Handler) timelineFilterFromRequest(
+	r *http.Request,
+) (model.CheckExecutionTimelineFilter, error) {
+	filter := model.CheckExecutionTimelineFilter{
+		ServiceID: chi.URLParam(r, "serviceId"),
+		CheckID:   chi.URLParam(r, "checkId"),
+	}
+
+	query := r.URL.Query()
+
+	if raw := query.Get("from"); raw != "" {
+		from, err := time.Parse(time.RFC3339, raw)
+		if err != nil {
+			return filter, err
+		}
+		filter.From = from
+	}
+
+	if raw := query.Get("to"); raw != "" {
+		to, err := time.Parse(time.RFC3339, raw)
+		if err != nil {
+			return filter, err
+		}
+		filter.To = to
+	}
+
+	filter.Bucket = model.CheckExecutionBucket(query.Get("bucket"))
+
+	fields, err := h.checkFields(filter.ServiceID, filter.CheckID)
+	if err != nil {
+		return filter, err
+	}
+	filter.Interval = fields.Interval
+
+	if !isAllowedBucket(filter.Bucket, fields.AllowedBuckets) {
+		return filter, fmt.Errorf(
+			"bucket %q is not allowed for check %s/%s; allowed buckets: %v",
+			filter.Bucket,
+			filter.ServiceID,
+			filter.CheckID,
+			allowedBuckets(fields.AllowedBuckets),
+		)
+	}
+
+	return filter, filter.Validate()
+}
+
+func allowedBuckets(allowed []string) []string {
+	if len(allowed) > 0 {
+		return allowed
+	}
+
+	return []string{
+		string(model.CheckExecutionBucketMinute),
+		string(model.CheckExecutionBucketHour),
+	}
+}
+
+func isAllowedBucket(bucket model.CheckExecutionBucket, allowed []string) bool {
+	if bucket == "" {
+		bucket = model.CheckExecutionBucketMinute
+	}
+
+	if len(allowed) == 0 {
+		return bucket == model.CheckExecutionBucketMinute ||
+			bucket == model.CheckExecutionBucketHour
+	}
+
+	for i := range allowed {
+		if model.CheckExecutionBucket(allowed[i]) == bucket {
+			return true
+		}
+	}
+
+	return false
+}