feat(#33): unify api error handling further

internal/application/common/errors.go

@@ -15,6 +15,7 @@ type APIError interface {
 	error
 	Status() int
 	Response() modelsv1.Error
+	InternalCauses() []error // not for sending to the client, but useful for logging
 }
 
 // ErrorMessageCode is a key to use for error messages in frontends or other automated systems interacting
@@ -44,32 +45,32 @@ const (
 
 // construct specific API errors
 
-func NewBadRequest(ctx context.Context, message ErrorMessageCode, details url.Values) APIError {
-	return NewAPIError(ctx, http.StatusBadRequest, message, details)
+func NewBadRequest(ctx context.Context, message ErrorMessageCode, details url.Values, internalCauses ...error) APIError {
+	return NewAPIError(ctx, http.StatusBadRequest, message, details, internalCauses...)
 }
 
-func NewUnauthorized(ctx context.Context, message ErrorMessageCode, details url.Values) APIError {
-	return NewAPIError(ctx, http.StatusUnauthorized, message, details)
+func NewUnauthorized(ctx context.Context, message ErrorMessageCode, details url.Values, internalCauses ...error) APIError {
+	return NewAPIError(ctx, http.StatusUnauthorized, message, details, internalCauses...)
 }
 
-func NewForbidden(ctx context.Context, message ErrorMessageCode, details url.Values) APIError {
-	return NewAPIError(ctx, http.StatusForbidden, message, details)
+func NewForbidden(ctx context.Context, message ErrorMessageCode, details url.Values, internalCauses ...error) APIError {
+	return NewAPIError(ctx, http.StatusForbidden, message, details, internalCauses...)
 }
 
-func NewNotFound(ctx context.Context, message ErrorMessageCode, details url.Values) APIError {
-	return NewAPIError(ctx, http.StatusNotFound, message, details)
+func NewNotFound(ctx context.Context, message ErrorMessageCode, details url.Values, internalCauses ...error) APIError {
+	return NewAPIError(ctx, http.StatusNotFound, message, details, internalCauses...)
 }
 
-func NewConflict(ctx context.Context, message ErrorMessageCode, details url.Values) APIError {
-	return NewAPIError(ctx, http.StatusConflict, message, details)
+func NewConflict(ctx context.Context, message ErrorMessageCode, details url.Values, internalCauses ...error) APIError {
+	return NewAPIError(ctx, http.StatusConflict, message, details, internalCauses...)
 }
 
-func NewInternalServerError(ctx context.Context, message ErrorMessageCode, details url.Values) APIError {
-	return NewAPIError(ctx, http.StatusInternalServerError, message, details)
+func NewInternalServerError(ctx context.Context, message ErrorMessageCode, details url.Values, internalCauses ...error) APIError {
+	return NewAPIError(ctx, http.StatusInternalServerError, message, details, internalCauses...)
 }
 
-func NewBadGateway(ctx context.Context, message ErrorMessageCode, details url.Values) APIError {
-	return NewAPIError(ctx, http.StatusBadGateway, message, details)
+func NewBadGateway(ctx context.Context, message ErrorMessageCode, details url.Values, internalCauses ...error) APIError {
+	return NewAPIError(ctx, http.StatusBadGateway, message, details, internalCauses...)
 }
 
 // check for API errors
@@ -110,7 +111,8 @@ func IsAPIError(err error) bool {
 const isoDateTimeFormat = "2006-01-02T15:04:05-07:00"
 
 // NewAPIError creates a generic API error from directly provided information.
-func NewAPIError(ctx context.Context, status int, message ErrorMessageCode, details url.Values) APIError {
+func NewAPIError(ctx context.Context, status int, message ErrorMessageCode, details url.Values, internalCauses ...error) APIError {
+
 	return &StatusError{
 		errStatus: status,
 		response: modelsv1.Error{
@@ -119,14 +121,16 @@ func NewAPIError(ctx context.Context, status int, message ErrorMessageCode, deta
 			Message:   string(message),
 			Details:   details,
 		},
+		internalCauses: internalCauses,
 	}
 }
 
 var _ error = (*StatusError)(nil)
 
 type StatusError struct {
-	errStatus int
-	response  modelsv1.Error
+	errStatus      int
+	response       modelsv1.Error
+	internalCauses []error
 }
 
 func (se *StatusError) Error() string {
@@ -141,6 +145,10 @@ func (se *StatusError) Response() modelsv1.Error {
 	return se.response
 }
 
+func (se *StatusError) InternalCauses() []error {
+	return se.internalCauses
+}
+
 func isAPIErrorWithStatus(status int, err error) bool {
 	apiError, ok := err.(APIError)
 	return ok && status == apiError.Status()

internal/application/web/endpoint.go

@@ -13,7 +13,8 @@ type (
 	Endpoint[Req, Res any]   func(ctx context.Context, request *Req, w http.ResponseWriter) (*Res, error)
 )
 
-func CreateHandler[Req, Res any](endpoint Endpoint[Req, Res],
+func CreateHandler[Req, Res any](
+	endpoint Endpoint[Req, Res],
 	requestHandler RequestHandler[Req],
 	responseHandler ResponseHandler[Res],
 ) http.Handler {
@@ -36,24 +37,25 @@ func CreateHandler[Req, Res any](endpoint Endpoint[Req, Res],
 		defer func() {
 			err := r.Body.Close()
 			if err != nil {
-				aulogging.InfoErrf(ctx, err, "Error when closing the request body. [error]: %v", err)
+				aulogging.WarnErrf(ctx, err, "error while closing the request body: %v", err)
 			}
 		}()
 
 		request, err := requestHandler(r, w)
 		if err != nil {
-			aulogging.InfoErrf(ctx, err, "An error occurred while parsing the request. [error]: %v", err)
+			SendErrorResponse(ctx, w, err)
 			return
 		}
 
 		response, err := endpoint(ctx, request, w)
 		if err != nil {
-			aulogging.InfoErrf(ctx, err, "An error occurred during the request. [error]: %v", err)
+			SendErrorResponse(ctx, w, err)
 			return
 		}
 
 		if err := responseHandler(ctx, response, w); err != nil {
-			aulogging.InfoErrf(ctx, err, "An error occurred during the handling of the response. [error]: %v", err)
+			// cannot SendErrorResponse(ctx, w, err) - likely already have started sending in responseHandler
+			aulogging.ErrorErrf(ctx, err, "An error occurred during the handling of the response - response may have been incomplete. [error]: %v", err)
 		}
 	})
 }

internal/application/web/response.go

@@ -3,6 +3,7 @@ package web
 import (
 	"context"
 	"encoding/json"
+	"fmt"
 	aulogging "github.com/StephanHCB/go-autumn-logging"
 	"github.com/eurofurence/reg-room-service/internal/application/common"
 	"net/http"
@@ -45,6 +46,11 @@ func SendErrorResponse(ctx context.Context, w http.ResponseWriter, err error) {
 // which contains relevant information about the failed request to the client.
 // The function will also set the http status according to the provided status.
 func SendAPIErrorResponse(ctx context.Context, w http.ResponseWriter, apiErr common.APIError) {
+	aulogging.InfoErrf(ctx, apiErr, fmt.Sprintf("api response status %d: %v", apiErr.Status(), apiErr))
+	for _, cause := range apiErr.InternalCauses() {
+		aulogging.InfoErrf(ctx, cause, fmt.Sprintf("... caused by: %v", cause))
+	}
+
 	w.WriteHeader(apiErr.Status())
 
 	EncodeToJSON(ctx, w, apiErr.Response())

internal/controller/v1/countdownctl/countdown_get.go

@@ -61,8 +61,7 @@ func (*Handler) GetCountdownRequest(r *http.Request, w http.ResponseWriter) (*Ge
 		aulogging.Warn(ctx, "mock time specified")
 		mockTime, err := time.Parse(mockTimeFormat, currentTimeIsoParam)
 		if err != nil {
-			web.SendErrorResponse(ctx, w, common.NewBadRequest(ctx, common.RequestParseFailed, common.Details("mock time specified but failed to parse")))
-			return nil, err
+			return nil, common.NewBadRequest(ctx, common.RequestParseFailed, common.Details("mock time specified but failed to parse"))
 		}
 		return &GetCountdownRequest{mockTime: &mockTime}, nil
 	}

internal/controller/v1/groupsctl/groups_delete.go

@@ -2,7 +2,6 @@ package groupsctl
 
 import (
 	"context"
-	"github.com/eurofurence/reg-room-service/internal/application/web"
 	"github.com/go-chi/chi/v5"
 	"net/http"
 
@@ -19,16 +18,13 @@ type DeleteGroupRequest struct {
 // Only Admins or the current group owner can do this.
 func (h *Controller) DeleteGroup(ctx context.Context, req *DeleteGroupRequest, w http.ResponseWriter) (*modelsv1.Empty, error) {
 	err := h.svc.DeleteGroup(ctx, req.groupID)
-	if err != nil {
-		web.SendErrorResponse(ctx, w, err)
-	}
 	return nil, err
 }
 
 // DeleteGroupRequest parses and returns a request containing information to call the DeleteGroup function.
 func (h *Controller) DeleteGroupRequest(r *http.Request, w http.ResponseWriter) (*DeleteGroupRequest, error) {
 	groupID := chi.URLParam(r, "uuid")
-	if err := validateGroupID(r.Context(), w, groupID); err != nil {
+	if err := validateGroupID(r.Context(), groupID); err != nil {
 		return nil, err
 	}
 

internal/controller/v1/groupsctl/groups_get.go

@@ -23,7 +23,6 @@ type ListGroupsRequest struct {
 func (h *Controller) ListGroups(ctx context.Context, req *ListGroupsRequest, w http.ResponseWriter) (*modelsv1.GroupList, error) {
 	groups, err := h.svc.FindGroups(ctx, req.MinSize, req.MaxSize, req.MemberIDs)
 	if err != nil {
-		web.SendErrorResponse(ctx, w, err)
 		return nil, err
 	}
 
@@ -41,16 +40,14 @@ func (h *Controller) ListGroupsRequest(r *http.Request, w http.ResponseWriter) (
 	queryIDs := query.Get("member_ids")
 	memberIDs, err := util.ParseMemberIDs(queryIDs)
 	if err != nil {
-		web.SendErrorResponse(ctx, w, common.NewBadRequest(ctx, common.RequestParseFailed, common.Details(err.Error())))
-		return nil, err
+		return nil, common.NewBadRequest(ctx, common.RequestParseFailed, common.Details(err.Error()))
 	}
 
 	req.MemberIDs = memberIDs
 	if minSize := query.Get("min_size"); minSize != "" {
 		val, err := util.ParseUInt[uint](minSize)
 		if err != nil {
-			web.SendErrorResponse(ctx, w, common.NewBadRequest(ctx, common.RequestParseFailed, common.Details(err.Error())))
-			return nil, err
+			return nil, common.NewBadRequest(ctx, common.RequestParseFailed, common.Details(err.Error()))
 		}
 
 		req.MinSize = val
@@ -59,12 +56,10 @@ func (h *Controller) ListGroupsRequest(r *http.Request, w http.ResponseWriter) (
 	if maxSize := query.Get("max_size"); maxSize != "" {
 		val, err := util.ParseInt[int](maxSize)
 		if err != nil {
-			web.SendErrorResponse(ctx, w, common.NewBadRequest(ctx, common.RequestParseFailed, common.Details(err.Error())))
-			return nil, err
+			return nil, common.NewBadRequest(ctx, common.RequestParseFailed, common.Details(err.Error()))
 		}
 		if val < -1 {
-			web.SendErrorResponse(ctx, w, common.NewBadRequest(ctx, common.RequestParseFailed, common.Details("maxSize cannot be less than -1")))
-			return nil, err
+			return nil, common.NewBadRequest(ctx, common.RequestParseFailed, common.Details("maxSize cannot be less than -1"))
 		}
 
 		req.MaxSize = val
@@ -84,7 +79,6 @@ type FindMyGroupRequest struct{}
 func (h *Controller) FindMyGroup(ctx context.Context, req *FindMyGroupRequest, w http.ResponseWriter) (*modelsv1.Group, error) {
 	group, err := h.svc.FindMyGroup(ctx)
 	if err != nil {
-		web.SendErrorResponse(ctx, w, err)
 		return nil, err
 	}
 
@@ -107,7 +101,6 @@ type FindGroupByIDRequest struct {
 func (h *Controller) FindGroupByID(ctx context.Context, req *FindGroupByIDRequest, w http.ResponseWriter) (*modelsv1.Group, error) {
 	grp, err := h.svc.GetGroupByID(ctx, req.GroupID)
 	if err != nil {
-		web.SendErrorResponse(ctx, w, err)
 		return nil, err
 	}
 
@@ -117,9 +110,7 @@ func (h *Controller) FindGroupByID(ctx context.Context, req *FindGroupByIDReques
 func (h *Controller) FindGroupByIDRequest(r *http.Request, w http.ResponseWriter) (*FindGroupByIDRequest, error) {
 	groupID := chi.URLParam(r, "uuid")
 	if _, err := uuid.Parse(groupID); err != nil {
-		ctx := r.Context()
-		web.SendErrorResponse(ctx, w, common.NewBadRequest(ctx, common.GroupIDInvalid, url.Values{"details": []string{"you must specify a valid uuid"}}))
-		return nil, err
+		return nil, common.NewBadRequest(r.Context(), common.GroupIDInvalid, url.Values{"details": []string{"you must specify a valid uuid"}})
 	}
 
 	req := &FindGroupByIDRequest{

internal/controller/v1/groupsctl/groups_post.go

@@ -2,8 +2,7 @@ package groupsctl
 
 import (
 	"context"
-	aulogging "github.com/StephanHCB/go-autumn-logging"
-	"github.com/eurofurence/reg-room-service/internal/application/web"
+	"errors"
 	"github.com/eurofurence/reg-room-service/internal/controller/v1/util"
 	"net/http"
 	"net/url"
@@ -29,15 +28,12 @@ type CreateGroupRequest struct {
 func (h *Controller) CreateGroup(ctx context.Context, req *CreateGroupRequest, w http.ResponseWriter) (*modelsv1.Empty, error) {
 	newGroupUUID, err := h.svc.CreateGroup(ctx, req.Group)
 	if err != nil {
-		web.SendErrorResponse(ctx, w, err)
 		return nil, err
 	}
 
 	requestURL, ok := ctx.Value(common.CtxKeyRequestURL{}).(*url.URL)
 	if !ok {
-		aulogging.Error(ctx, "could not retrieve base URL from context")
-		web.SendErrorResponse(ctx, w, nil)
-		return nil, nil
+		return nil, errors.New("could not retrieve base URL from context - this is an implementation error")
 	}
 
 	w.Header().Set("Location", path.Join(requestURL.Path, newGroupUUID))
@@ -48,11 +44,7 @@ func (h *Controller) CreateGroupRequest(r *http.Request, w http.ResponseWriter)
 	var group modelsv1.GroupCreate
 
 	if err := util.NewStrictJSONDecoder(r.Body).Decode(&group); err != nil {
-		ctx := r.Context()
-		web.SendErrorResponse(ctx, w, common.NewBadRequest(ctx,
-			common.GroupDataInvalid, common.Details("invalid json provided"),
-		))
-		return nil, err
+		return nil, common.NewBadRequest(r.Context(), common.GroupDataInvalid, common.Details("invalid json provided"))
 	}
 
 	cgr := &CreateGroupRequest{

internal/controller/v1/groupsctl/groups_put.go

@@ -2,8 +2,7 @@ package groupsctl
 
 import (
 	"context"
-	aulogging "github.com/StephanHCB/go-autumn-logging"
-	"github.com/eurofurence/reg-room-service/internal/application/web"
+	"errors"
 	"github.com/eurofurence/reg-room-service/internal/controller/v1/util"
 	"github.com/go-chi/chi/v5"
 	"net/http"
@@ -22,14 +21,12 @@ type UpdateGroupRequest struct {
 // Admins or the current group owner can change the group owner to any member of the group.
 func (h *Controller) UpdateGroup(ctx context.Context, req *UpdateGroupRequest, w http.ResponseWriter) (*modelsv1.Empty, error) {
 	if err := h.svc.UpdateGroup(ctx, req.Group); err != nil {
-		web.SendErrorResponse(ctx, w, err)
 		return nil, err
 	}
 
 	reqURL, ok := ctx.Value(common.CtxKeyRequestURL{}).(*url.URL)
 	if !ok {
-		aulogging.Error(ctx, "unable to retrieve URL from context")
-		return nil, nil
+		return nil, errors.New("unable to retrieve URL from context - this is an implementation error")
 	}
 
 	w.Header().Set("Location", reqURL.Path)
@@ -41,15 +38,14 @@ func (h *Controller) UpdateGroupRequest(r *http.Request, w http.ResponseWriter)
 	ctx := r.Context()
 
 	groupID := chi.URLParam(r, "uuid")
-	if err := validateGroupID(ctx, w, groupID); err != nil {
+	if err := validateGroupID(ctx, groupID); err != nil {
 		return nil, err
 	}
 
 	var group modelsv1.Group
 
 	if err := util.NewStrictJSONDecoder(r.Body).Decode(&group); err != nil {
-		web.SendErrorResponse(ctx, w, common.NewBadRequest(ctx, common.GroupDataInvalid, common.Details("invalid json provided")))
-		return nil, err
+		return nil, common.NewBadRequest(ctx, common.GroupDataInvalid, common.Details("invalid json provided"))
 	}
 
 	group.ID = groupID

internal/controller/v1/groupsctl/members_delete.go

@@ -2,7 +2,6 @@ package groupsctl
 
 import (
 	"context"
-	"github.com/eurofurence/reg-room-service/internal/application/web"
 	"github.com/eurofurence/reg-room-service/internal/controller/v1/util"
 	"github.com/go-chi/chi/v5"
 	"net/http"
@@ -21,24 +20,25 @@ type RemoveGroupMemberRequest struct {
 //
 // Details see OpenAPI spec.
 func (h *Controller) RemoveGroupMember(ctx context.Context, req *RemoveGroupMemberRequest, w http.ResponseWriter) (*modelsv1.Empty, error) {
+	// TODO
+
 	return nil, nil
 }
 
 // RemoveGroupMemberRequest validates and creates the request for the RemoveGroupMember operation.
 func (h *Controller) RemoveGroupMemberRequest(r *http.Request, w http.ResponseWriter) (*RemoveGroupMemberRequest, error) {
 	const uuidParam, badeNumberParam = "uuid", "badgenumber"
 
+	ctx := r.Context()
+
 	groupID := chi.URLParam(r, uuidParam)
-	if err := validateGroupID(r.Context(), w, groupID); err != nil {
+	if err := validateGroupID(ctx, groupID); err != nil {
 		return nil, err
 	}
 
 	badgeNumber, err := util.ParseUInt[uint](chi.URLParam(r, badeNumberParam))
 	if err != nil {
-		ctx := r.Context()
-		web.SendErrorResponse(ctx, w,
-			common.NewBadRequest(ctx, common.GroupDataInvalid, common.Details("invalid type for badge number")))
-		return nil, err
+		return nil, common.NewBadRequest(ctx, common.GroupDataInvalid, common.Details("invalid type for badge number"))
 	}
 
 	return &RemoveGroupMemberRequest{groupID, badgeNumber}, nil