Added a postgres sink implementation.

internal/sinks/postgres/map.go

@@ -0,0 +1,343 @@
+package postgres
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"strings"
+	"time"
+
+	fkevent "gitea.maximumdirect.net/ejr/feedkit/event"
+	fksinks "gitea.maximumdirect.net/ejr/feedkit/sinks"
+	"gitea.maximumdirect.net/ejr/weatherfeeder/model"
+	"gitea.maximumdirect.net/ejr/weatherfeeder/standards"
+)
+
+func mapPostgresEvent(_ context.Context, e fkevent.Event) ([]fksinks.PostgresWrite, error) {
+	schema := strings.TrimSpace(e.Schema)
+	switch schema {
+	case standards.SchemaWeatherObservationV1:
+		return mapObservationEvent(e)
+	case standards.SchemaWeatherForecastV1:
+		return mapForecastEvent(e)
+	case standards.SchemaWeatherAlertV1:
+		return mapAlertEvent(e)
+	default:
+		return nil, nil
+	}
+}
+
+func mapObservationEvent(e fkevent.Event) ([]fksinks.PostgresWrite, error) {
+	obs, err := decodePayload[model.WeatherObservation](e.Payload)
+	if err != nil {
+		return nil, fmt.Errorf("decode observation payload: %w", err)
+	}
+	if obs.Timestamp.IsZero() {
+		return nil, fmt.Errorf("decode observation payload: timestamp is required")
+	}
+
+	observedAt := obs.Timestamp.UTC()
+	writes := make([]fksinks.PostgresWrite, 0, 1+len(obs.CloudLayers)+len(obs.PresentWeather))
+
+	writes = append(writes, fksinks.PostgresWrite{
+		Table: tableObservations,
+		Values: map[string]any{
+			"event_id":                  e.ID,
+			"event_kind":                string(e.Kind),
+			"event_source":              e.Source,
+			"event_schema":              e.Schema,
+			"event_emitted_at":          e.EmittedAt.UTC(),
+			"event_effective_at":        nullableTime(e.EffectiveAt),
+			"station_id":                nullableString(obs.StationID),
+			"station_name":              nullableString(obs.StationName),
+			"observed_at":               observedAt,
+			"condition_code":            int(obs.ConditionCode),
+			"condition_text":            nullableString(obs.ConditionText),
+			"is_day":                    nullableBool(obs.IsDay),
+			"provider_raw_description":  nullableString(obs.ProviderRawDescription),
+			"text_description":          nullableString(obs.TextDescription),
+			"icon_url":                  nullableString(obs.IconURL),
+			"temperature_c":             nullableFloat64(obs.TemperatureC),
+			"dewpoint_c":                nullableFloat64(obs.DewpointC),
+			"wind_direction_degrees":    nullableFloat64(obs.WindDirectionDegrees),
+			"wind_speed_kmh":            nullableFloat64(obs.WindSpeedKmh),
+			"wind_gust_kmh":             nullableFloat64(obs.WindGustKmh),
+			"barometric_pressure_pa":    nullableFloat64(obs.BarometricPressurePa),
+			"sea_level_pressure_pa":     nullableFloat64(obs.SeaLevelPressurePa),
+			"visibility_meters":         nullableFloat64(obs.VisibilityMeters),
+			"relative_humidity_percent": nullableFloat64(obs.RelativeHumidityPercent),
+			"apparent_temperature_c":    nullableFloat64(obs.ApparentTemperatureC),
+			"elevation_meters":          nullableFloat64(obs.ElevationMeters),
+			"raw_message":               nullableString(obs.RawMessage),
+		},
+	})
+
+	for i, cl := range obs.CloudLayers {
+		writes = append(writes, fksinks.PostgresWrite{
+			Table: tableObservationCloudLayers,
+			Values: map[string]any{
+				"event_id":    e.ID,
+				"layer_index": i,
+				"observed_at": observedAt,
+				"base_meters": nullableFloat64(cl.BaseMeters),
+				"amount":      nullableString(cl.Amount),
+			},
+		})
+	}
+
+	for i, pw := range obs.PresentWeather {
+		rawText, err := compactJSONText(pw.Raw)
+		if err != nil {
+			return nil, fmt.Errorf("observation presentWeather[%d].raw: %w", i, err)
+		}
+		writes = append(writes, fksinks.PostgresWrite{
+			Table: tableObservationPresentWeather,
+			Values: map[string]any{
+				"event_id":      e.ID,
+				"weather_index": i,
+				"observed_at":   observedAt,
+				"raw_text":      rawText,
+			},
+		})
+	}
+
+	return writes, nil
+}
+
+func mapForecastEvent(e fkevent.Event) ([]fksinks.PostgresWrite, error) {
+	run, err := decodePayload[model.WeatherForecastRun](e.Payload)
+	if err != nil {
+		return nil, fmt.Errorf("decode forecast payload: %w", err)
+	}
+	if run.IssuedAt.IsZero() {
+		return nil, fmt.Errorf("decode forecast payload: issuedAt is required")
+	}
+	if strings.TrimSpace(string(run.Product)) == "" {
+		return nil, fmt.Errorf("decode forecast payload: product is required")
+	}
+
+	issuedAt := run.IssuedAt.UTC()
+	writes := make([]fksinks.PostgresWrite, 0, 1+len(run.Periods))
+
+	writes = append(writes, fksinks.PostgresWrite{
+		Table: tableForecasts,
+		Values: map[string]any{
+			"event_id":           e.ID,
+			"event_kind":         string(e.Kind),
+			"event_source":       e.Source,
+			"event_schema":       e.Schema,
+			"event_emitted_at":   e.EmittedAt.UTC(),
+			"event_effective_at": nullableTime(e.EffectiveAt),
+			"location_id":        nullableString(run.LocationID),
+			"location_name":      nullableString(run.LocationName),
+			"issued_at":          issuedAt,
+			"updated_at":         nullableTime(run.UpdatedAt),
+			"product":            string(run.Product),
+			"latitude":           nullableFloat64(run.Latitude),
+			"longitude":          nullableFloat64(run.Longitude),
+			"elevation_meters":   nullableFloat64(run.ElevationMeters),
+			"period_count":       len(run.Periods),
+		},
+	})
+
+	for i, p := range run.Periods {
+		if p.StartTime.IsZero() || p.EndTime.IsZero() {
+			return nil, fmt.Errorf("decode forecast payload: periods[%d] startTime/endTime are required", i)
+		}
+		writes = append(writes, fksinks.PostgresWrite{
+			Table: tableForecastPeriods,
+			Values: map[string]any{
+				"run_event_id":                         e.ID,
+				"period_index":                         i,
+				"issued_at":                            issuedAt,
+				"start_time":                           p.StartTime.UTC(),
+				"end_time":                             p.EndTime.UTC(),
+				"name":                                 nullableString(p.Name),
+				"is_day":                               nullableBool(p.IsDay),
+				"condition_code":                       int(p.ConditionCode),
+				"condition_text":                       nullableString(p.ConditionText),
+				"provider_raw_description":             nullableString(p.ProviderRawDescription),
+				"text_description":                     nullableString(p.TextDescription),
+				"detailed_text":                        nullableString(p.DetailedText),
+				"icon_url":                             nullableString(p.IconURL),
+				"temperature_c":                        nullableFloat64(p.TemperatureC),
+				"temperature_c_min":                    nullableFloat64(p.TemperatureCMin),
+				"temperature_c_max":                    nullableFloat64(p.TemperatureCMax),
+				"dewpoint_c":                           nullableFloat64(p.DewpointC),
+				"relative_humidity_percent":            nullableFloat64(p.RelativeHumidityPercent),
+				"wind_direction_degrees":               nullableFloat64(p.WindDirectionDegrees),
+				"wind_speed_kmh":                       nullableFloat64(p.WindSpeedKmh),
+				"wind_gust_kmh":                        nullableFloat64(p.WindGustKmh),
+				"barometric_pressure_pa":               nullableFloat64(p.BarometricPressurePa),
+				"visibility_meters":                    nullableFloat64(p.VisibilityMeters),
+				"apparent_temperature_c":               nullableFloat64(p.ApparentTemperatureC),
+				"cloud_cover_percent":                  nullableFloat64(p.CloudCoverPercent),
+				"probability_of_precipitation_percent": nullableFloat64(p.ProbabilityOfPrecipitationPercent),
+				"precipitation_amount_mm":              nullableFloat64(p.PrecipitationAmountMm),
+				"snowfall_depth_mm":                    nullableFloat64(p.SnowfallDepthMM),
+				"uv_index":                             nullableFloat64(p.UVIndex),
+			},
+		})
+	}
+
+	return writes, nil
+}
+
+func mapAlertEvent(e fkevent.Event) ([]fksinks.PostgresWrite, error) {
+	run, err := decodePayload[model.WeatherAlertRun](e.Payload)
+	if err != nil {
+		return nil, fmt.Errorf("decode alert payload: %w", err)
+	}
+	if run.AsOf.IsZero() {
+		return nil, fmt.Errorf("decode alert payload: asOf is required")
+	}
+
+	asOf := run.AsOf.UTC()
+	writes := make([]fksinks.PostgresWrite, 0, 1+len(run.Alerts)+countAlertReferences(run.Alerts))
+
+	writes = append(writes, fksinks.PostgresWrite{
+		Table: tableAlertRuns,
+		Values: map[string]any{
+			"event_id":           e.ID,
+			"event_kind":         string(e.Kind),
+			"event_source":       e.Source,
+			"event_schema":       e.Schema,
+			"event_emitted_at":   e.EmittedAt.UTC(),
+			"event_effective_at": nullableTime(e.EffectiveAt),
+			"location_id":        nullableString(run.LocationID),
+			"location_name":      nullableString(run.LocationName),
+			"as_of":              asOf,
+			"latitude":           nullableFloat64(run.Latitude),
+			"longitude":          nullableFloat64(run.Longitude),
+			"alert_count":        len(run.Alerts),
+		},
+	})
+
+	for i, a := range run.Alerts {
+		if strings.TrimSpace(a.ID) == "" {
+			return nil, fmt.Errorf("decode alert payload: alerts[%d].id is required", i)
+		}
+
+		writes = append(writes, fksinks.PostgresWrite{
+			Table: tableAlerts,
+			Values: map[string]any{
+				"run_event_id":     e.ID,
+				"alert_index":      i,
+				"as_of":            asOf,
+				"alert_id":         a.ID,
+				"event":            nullableString(a.Event),
+				"headline":         nullableString(a.Headline),
+				"severity":         nullableString(a.Severity),
+				"urgency":          nullableString(a.Urgency),
+				"certainty":        nullableString(a.Certainty),
+				"status":           nullableString(a.Status),
+				"message_type":     nullableString(a.MessageType),
+				"category":         nullableString(a.Category),
+				"response":         nullableString(a.Response),
+				"description":      nullableString(a.Description),
+				"instruction":      nullableString(a.Instruction),
+				"sent":             nullableTime(a.Sent),
+				"effective":        nullableTime(a.Effective),
+				"onset":            nullableTime(a.Onset),
+				"expires":          nullableTime(a.Expires),
+				"area_description": nullableString(a.AreaDescription),
+				"sender_name":      nullableString(a.SenderName),
+				"reference_count":  len(a.References),
+			},
+		})
+
+		for j, ref := range a.References {
+			writes = append(writes, fksinks.PostgresWrite{
+				Table: tableAlertReferences,
+				Values: map[string]any{
+					"run_event_id":    e.ID,
+					"alert_index":     i,
+					"reference_index": j,
+					"as_of":           asOf,
+					"id":              nullableString(ref.ID),
+					"identifier":      nullableString(ref.Identifier),
+					"sender":          nullableString(ref.Sender),
+					"sent":            nullableTime(ref.Sent),
+				},
+			})
+		}
+	}
+
+	return writes, nil
+}
+
+func decodePayload[T any](payload any) (T, error) {
+	var out T
+	if payload == nil {
+		return out, fmt.Errorf("payload is nil")
+	}
+
+	if typed, ok := payload.(T); ok {
+		return typed, nil
+	}
+	if ptr, ok := payload.(*T); ok {
+		if ptr == nil {
+			return out, fmt.Errorf("payload pointer is nil")
+		}
+		return *ptr, nil
+	}
+
+	b, err := json.Marshal(payload)
+	if err != nil {
+		return out, fmt.Errorf("marshal payload: %w", err)
+	}
+	if err := json.Unmarshal(b, &out); err != nil {
+		return out, fmt.Errorf("unmarshal payload: %w", err)
+	}
+	return out, nil
+}
+
+func countAlertReferences(alerts []model.WeatherAlert) int {
+	total := 0
+	for _, a := range alerts {
+		total += len(a.References)
+	}
+	return total
+}
+
+func nullableString(s string) any {
+	if strings.TrimSpace(s) == "" {
+		return nil
+	}
+	return s
+}
+
+func nullableFloat64(v *float64) any {
+	if v == nil {
+		return nil
+	}
+	return *v
+}
+
+func nullableBool(v *bool) any {
+	if v == nil {
+		return nil
+	}
+	return *v
+}
+
+func nullableTime(v *time.Time) any {
+	if v == nil || v.IsZero() {
+		return nil
+	}
+	return v.UTC()
+}
+
+func compactJSONText(v any) (any, error) {
+	if v == nil {
+		return nil, nil
+	}
+	b, err := json.Marshal(v)
+	if err != nil {
+		return nil, err
+	}
+	if string(b) == "null" {
+		return nil, nil
+	}
+	return string(b), nil
+}