dnswatcher/internal/handlers/handlers.go

// Package handlers provides HTTP request handlers.
package handlers

import (
	"encoding/json"
	"log/slog"
	"net/http"

	"go.uber.org/fx"

	"sneak.berlin/go/dnswatcher/internal/globals"
	"sneak.berlin/go/dnswatcher/internal/healthcheck"
	"sneak.berlin/go/dnswatcher/internal/logger"
	"sneak.berlin/go/dnswatcher/internal/notify"
	"sneak.berlin/go/dnswatcher/internal/state"
)

// Params contains dependencies for Handlers.
type Params struct {
	fx.In

	Logger      *logger.Logger
	Globals     *globals.Globals
	Healthcheck *healthcheck.Healthcheck
	State       *state.State
	Notify      *notify.Service
}

// Handlers provides HTTP request handlers.
type Handlers struct {
	log           *slog.Logger
	params        *Params
	globals       *globals.Globals
	hc            *healthcheck.Healthcheck
	state         *state.State
	notifyHistory *notify.AlertHistory
}

// New creates a new Handlers instance.
func New(_ fx.Lifecycle, params Params) (*Handlers, error) {
	return &Handlers{
		log:           params.Logger.Get(),
		params:        &params,
		globals:       params.Globals,
		hc:            params.Healthcheck,
		state:         params.State,
		notifyHistory: params.Notify.History(),
	}, nil
}

func (h *Handlers) respondJSON(
	writer http.ResponseWriter,
	_ *http.Request,
	data any,
	status int,
) {
	writer.Header().Set("Content-Type", "application/json")
	writer.WriteHeader(status)

	if data != nil {
		err := json.NewEncoder(writer).Encode(data)
		if err != nil {
			h.log.Error("json encode error", "error", err)
		}
	}
}