all: sync with master; upd chlog

internal/aghhttp/json.go

@@ -0,0 +1,142 @@
+package aghhttp
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"strconv"
+	"time"
+
+	"github.com/AdguardTeam/golibs/httphdr"
+	"github.com/AdguardTeam/golibs/log"
+)
+
+// JSON Utilities
+
+// nsecPerMsec is the number of nanoseconds in a millisecond.
+const nsecPerMsec = float64(time.Millisecond / time.Nanosecond)
+
+// JSONDuration is a time.Duration that can be decoded from JSON and encoded
+// into JSON according to our API conventions.
+type JSONDuration time.Duration
+
+// type check
+var _ json.Marshaler = JSONDuration(0)
+
+// MarshalJSON implements the json.Marshaler interface for JSONDuration.  err is
+// always nil.
+func (d JSONDuration) MarshalJSON() (b []byte, err error) {
+	msec := float64(time.Duration(d)) / nsecPerMsec
+	b = strconv.AppendFloat(nil, msec, 'f', -1, 64)
+
+	return b, nil
+}
+
+// type check
+var _ json.Unmarshaler = (*JSONDuration)(nil)
+
+// UnmarshalJSON implements the json.Marshaler interface for *JSONDuration.
+func (d *JSONDuration) UnmarshalJSON(b []byte) (err error) {
+	if d == nil {
+		return fmt.Errorf("json duration is nil")
+	}
+
+	msec, err := strconv.ParseFloat(string(b), 64)
+	if err != nil {
+		return fmt.Errorf("parsing json time: %w", err)
+	}
+
+	*d = JSONDuration(int64(msec * nsecPerMsec))
+
+	return nil
+}
+
+// JSONTime is a time.Time that can be decoded from JSON and encoded into JSON
+// according to our API conventions.
+type JSONTime time.Time
+
+// type check
+var _ json.Marshaler = JSONTime{}
+
+// MarshalJSON implements the json.Marshaler interface for JSONTime.  err is
+// always nil.
+func (t JSONTime) MarshalJSON() (b []byte, err error) {
+	msec := float64(time.Time(t).UnixNano()) / nsecPerMsec
+	b = strconv.AppendFloat(nil, msec, 'f', -1, 64)
+
+	return b, nil
+}
+
+// type check
+var _ json.Unmarshaler = (*JSONTime)(nil)
+
+// UnmarshalJSON implements the json.Marshaler interface for *JSONTime.
+func (t *JSONTime) UnmarshalJSON(b []byte) (err error) {
+	if t == nil {
+		return fmt.Errorf("json time is nil")
+	}
+
+	msec, err := strconv.ParseFloat(string(b), 64)
+	if err != nil {
+		return fmt.Errorf("parsing json time: %w", err)
+	}
+
+	*t = JSONTime(time.Unix(0, int64(msec*nsecPerMsec)).UTC())
+
+	return nil
+}
+
+// WriteJSONResponse writes headers with the code, encodes resp into w, and logs
+// any errors it encounters.  r is used to get additional information from the
+// request.
+func WriteJSONResponse(w http.ResponseWriter, r *http.Request, code int, resp any) {
+	h := w.Header()
+	h.Set(httphdr.ContentType, HdrValApplicationJSON)
+	h.Set(httphdr.Server, UserAgent())
+
+	w.WriteHeader(code)
+
+	err := json.NewEncoder(w).Encode(resp)
+	if err != nil {
+		log.Error("aghhttp: writing json resp to %s %s: %s", r.Method, r.URL.Path, err)
+	}
+}
+
+// WriteJSONResponseOK writes headers with the code 200 OK, encodes v into w,
+// and logs any errors it encounters.  r is used to get additional information
+// from the request.
+func WriteJSONResponseOK(w http.ResponseWriter, r *http.Request, v any) {
+	WriteJSONResponse(w, r, http.StatusOK, v)
+}
+
+// ErrorCode is the error code as used by the HTTP API.  See the ErrorCode
+// definition in the OpenAPI specification.
+type ErrorCode string
+
+// ErrorCode constants.
+//
+// TODO(a.garipov): Expand and document codes.
+const (
+	// ErrorCodeTMP000 is the temporary error code used for all errors.
+	ErrorCodeTMP000 = ""
+)
+
+// HTTPAPIErrorResp is the error response as used by the HTTP API.  See the
+// BadRequestResp, InternalServerErrorResp, and similar objects in the OpenAPI
+// specification.
+type HTTPAPIErrorResp struct {
+	Code ErrorCode `json:"code"`
+	Msg  string    `json:"msg"`
+}
+
+// WriteJSONResponseError encodes err as a JSON error into w, and logs any
+// errors it encounters.  r is used to get additional information from the
+// request.
+func WriteJSONResponseError(w http.ResponseWriter, r *http.Request, err error) {
+	log.Error("aghhttp: writing json error to %s %s: %s", r.Method, r.URL.Path, err)
+
+	WriteJSONResponse(w, r, http.StatusUnprocessableEntity, &HTTPAPIErrorResp{
+		Code: ErrorCodeTMP000,
+		Msg:  err.Error(),
+	})
+}