Files
tiny-forge/internal/api/response.go

57 lines
1.8 KiB
Go

package api
import (
"encoding/json"
"log/slog"
"net/http"
"reflect"
)
// envelope is the standard API response wrapper.
type envelope struct {
Success bool `json:"success"`
Data any `json:"data,omitempty"`
Error string `json:"error,omitempty"`
}
// respondJSON writes a JSON success response with the given status code and data.
// Nil slices are converted to empty arrays to avoid "null" in JSON output.
func respondJSON(w http.ResponseWriter, status int, data any) {
// Convert nil slices to empty arrays so JSON encodes as [] not null.
if data != nil {
v := reflect.ValueOf(data)
if v.Kind() == reflect.Slice && v.IsNil() {
data = reflect.MakeSlice(v.Type(), 0, 0).Interface()
}
}
w.Header().Set("Content-Type", "application/json")
w.WriteHeader(status)
if err := json.NewEncoder(w).Encode(envelope{Success: true, Data: data}); err != nil {
slog.Error("encode response", "error", err)
}
}
// respondError writes a JSON error response with the given status code and message.
func respondError(w http.ResponseWriter, status int, msg string) {
w.Header().Set("Content-Type", "application/json")
w.WriteHeader(status)
if err := json.NewEncoder(w).Encode(envelope{Success: false, Error: msg}); err != nil {
slog.Error("encode error response", "error", err)
}
}
// respondNotFound writes a 404 JSON error response for the given entity type.
func respondNotFound(w http.ResponseWriter, entity string) {
respondError(w, http.StatusNotFound, entity+" not found")
}
// decodeJSON reads and decodes the request body into the given value.
// Returns false and writes a 400 error response if decoding fails.
func decodeJSON(w http.ResponseWriter, r *http.Request, v any) bool {
if err := json.NewDecoder(r.Body).Decode(v); err != nil {
respondError(w, http.StatusBadRequest, "invalid JSON: "+err.Error())
return false
}
return true
}