openapi3filter: add context to Validator Middleware's ErrFunc and Log…

…Func functions (#953)

* add context to Validator Middleware's ErrFunc and LogFunc functions

* update existing ErrFunc and LogFunc instead of creating new ones and updated docs

---------

Co-authored-by: ap7u5 <christian.radow@huk-coburg.de>

.github/docs/openapi3filter.txt

@@ -182,7 +182,7 @@ type ErrCode int
     occur during validation. These may be used to write an appropriate response
     in ErrFunc.
 
-type ErrFunc func(w http.ResponseWriter, status int, code ErrCode, err error)
+type ErrFunc func(ctx context.Context, w http.ResponseWriter, status int, code ErrCode, err error)
     ErrFunc handles errors that may occur during validation.
 
 type ErrorEncoder func(ctx context.Context, err error, w http.ResponseWriter)
@@ -198,7 +198,7 @@ type Headerer interface {
     Headerer, the provided headers will be applied to the response writer,
     after the Content-Type is set.
 
-type LogFunc func(message string, err error)
+type LogFunc func(ctx context.Context, message string, err error)
     LogFunc handles log messages that may occur during validation.
 
 type Options struct {

openapi3filter/middleware.go

@@ -2,6 +2,7 @@ package openapi3filter
 
 import (
 	"bytes"
+	"context"
 	"io"
 	"log"
 	"net/http"
@@ -19,10 +20,10 @@ type Validator struct {
 }
 
 // ErrFunc handles errors that may occur during validation.
-type ErrFunc func(w http.ResponseWriter, status int, code ErrCode, err error)
+type ErrFunc func(ctx context.Context, w http.ResponseWriter, status int, code ErrCode, err error)
 
 // LogFunc handles log messages that may occur during validation.
-type LogFunc func(message string, err error)
+type LogFunc func(ctx context.Context, message string, err error)
 
 // ErrCode is used for classification of different types of errors that may
 // occur during validation. These may be used to write an appropriate response
@@ -61,10 +62,10 @@ func (e ErrCode) responseText() string {
 func NewValidator(router routers.Router, options ...ValidatorOption) *Validator {
 	v := &Validator{
 		router: router,
-		errFunc: func(w http.ResponseWriter, status int, code ErrCode, _ error) {
+		errFunc: func(_ context.Context, w http.ResponseWriter, status int, code ErrCode, _ error) {
 			http.Error(w, code.responseText(), status)
 		},
-		logFunc: func(message string, err error) {
+		logFunc: func(_ context.Context, message string, err error) {
 			log.Printf("%s: %v", message, err)
 		},
 	}
@@ -117,10 +118,11 @@ func ValidationOptions(options Options) ValidatorOption {
 // request and response validation.
 func (v *Validator) Middleware(h http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		ctx := r.Context()
 		route, pathParams, err := v.router.FindRoute(r)
 		if err != nil {
-			v.logFunc("validation error: failed to find route for "+r.URL.String(), err)
-			v.errFunc(w, http.StatusNotFound, ErrCodeCannotFindRoute, err)
+			v.logFunc(ctx, "validation error: failed to find route for "+r.URL.String(), err)
+			v.errFunc(ctx, w, http.StatusNotFound, ErrCodeCannotFindRoute, err)
 			return
 		}
 		requestValidationInput := &RequestValidationInput{
@@ -129,9 +131,9 @@ func (v *Validator) Middleware(h http.Handler) http.Handler {
 			Route:      route,
 			Options:    &v.options,
 		}
-		if err = ValidateRequest(r.Context(), requestValidationInput); err != nil {
-			v.logFunc("invalid request", err)
-			v.errFunc(w, http.StatusBadRequest, ErrCodeRequestInvalid, err)
+		if err = ValidateRequest(ctx, requestValidationInput); err != nil {
+			v.logFunc(ctx, "invalid request", err)
+			v.errFunc(ctx, w, http.StatusBadRequest, ErrCodeRequestInvalid, err)
 			return
 		}
 
@@ -144,22 +146,22 @@ func (v *Validator) Middleware(h http.Handler) http.Handler {
 
 		h.ServeHTTP(wr, r)
 
-		if err = ValidateResponse(r.Context(), &ResponseValidationInput{
+		if err = ValidateResponse(ctx, &ResponseValidationInput{
 			RequestValidationInput: requestValidationInput,
 			Status:                 wr.statusCode(),
 			Header:                 wr.Header(),
 			Body:                   io.NopCloser(bytes.NewBuffer(wr.bodyContents())),
 			Options:                &v.options,
 		}); err != nil {
-			v.logFunc("invalid response", err)
+			v.logFunc(ctx, "invalid response", err)
 			if v.strict {
-				v.errFunc(w, http.StatusInternalServerError, ErrCodeResponseInvalid, err)
+				v.errFunc(ctx, w, http.StatusInternalServerError, ErrCodeResponseInvalid, err)
 			}
 			return
 		}
 
 		if err = wr.flushBodyContents(); err != nil {
-			v.logFunc("failed to write response", err)
+			v.logFunc(ctx, "failed to write response", err)
 		}
 	})
 }

openapi3filter/middleware_test.go

@@ -2,6 +2,7 @@ package openapi3filter_test
 
 import (
 	"bytes"
+	"context"
 	"encoding/json"
 	"fmt"
 	"io"
@@ -489,7 +490,7 @@ paths:
 	// testing a service against its spec in development and CI. In production,
 	// availability may be more important than strictness.
 	v := openapi3filter.NewValidator(router, openapi3filter.Strict(true),
-		openapi3filter.OnErr(func(w http.ResponseWriter, status int, code openapi3filter.ErrCode, err error) {
+		openapi3filter.OnErr(func(_ context.Context, w http.ResponseWriter, status int, code openapi3filter.ErrCode, err error) {
 			// Customize validation error responses to use JSON
 			w.Header().Set("Content-Type", "application/json")
 			w.WriteHeader(status)