github.com/google/go-safeweb@v0.0.0-20231219055052-64d8cfc90fbb/examples/sample-application/secure/dispatcher.go (about)

     1  // Copyright 2020 Google LLC
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //	https://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  //go:build go1.16
    16  // +build go1.16
    17  
    18  package secure
    19  
    20  import (
    21  	"net/http"
    22  
    23  	"github.com/google/go-safeweb/safehttp"
    24  
    25  	"github.com/google/go-safeweb/examples/sample-application/secure/responses"
    26  	"github.com/google/go-safeweb/examples/sample-application/secure/templates"
    27  )
    28  
    29  // dispatcher is a custom dispatcher implementation. See
    30  // https://pkg.go.dev/github.com/google/go-safeweb/safehttp#hdr-Dispatcher.
    31  type dispatcher struct {
    32  	// No need for a Write method, the default dispatcher knows how to write all
    33  	// non-error responses we use in this project.
    34  	safehttp.DefaultDispatcher
    35  }
    36  
    37  func (d dispatcher) Error(rw http.ResponseWriter, resp safehttp.ErrorResponse) error {
    38  	if ce, ok := resp.(responses.Error); ok {
    39  		rw.Header().Set("Content-Type", "text/html; charset=utf-8")
    40  		rw.WriteHeader(int(ce.Code()))
    41  		return templates.All.ExecuteTemplate(rw, "error.tpl.html", ce.Message)
    42  	}
    43  	// Calling the default dispatcher in case we have no custom responses that match.
    44  	// This is strongly advised.
    45  	return d.DefaultDispatcher.Error(rw, resp)
    46  }