loki/pkg/querier/http.go

package querier

import (
	"encoding/json"
	"net/http"
	"net/url"
	"strconv"
	"time"

	"github.com/grafana/logish/pkg/logproto"
)

const (
	defaultQueryLimit = 100
	defaulSince       = 1 * time.Hour
)

func intParam(values url.Values, name string, def int) (int, error) {
	value := values.Get("limit")
	if value == "" {
		return def, nil
	}

	return strconv.Atoi(value)
}

func unixTimeParam(values url.Values, name string, def time.Time) (time.Time, error) {
	value := values.Get("limit")
	if value == "" {
		return def, nil
	}

	secs, err := strconv.ParseInt(value, 10, 64)
	if err != nil {
		return time.Time{}, err
	}

	return time.Unix(secs, 0), nil
}

func (q *Querier) QueryHandler(w http.ResponseWriter, r *http.Request) {
	params := r.URL.Query()
	query := params.Get("query")
	limit, err := intParam(params, "limit", defaultQueryLimit)
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	now := time.Now()
	start, err := unixTimeParam(params, "start", now.Add(-defaulSince))
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	end, err := unixTimeParam(params, "end", now)
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	request := logproto.QueryRequest{
		Query: query,
		Limit: uint32(limit),
		Start: start,
		End:   end,
	}
	result, err := q.Query(r.Context(), &request)
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	if err := json.NewEncoder(w).Encode(result); err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}
}