Add content-type to route.

mark.george / httpcat

Browse code Add content-type to route. closes #7
1 parent b3c5df7 commit 16a302889fa8f57eba9bdcef27c06f98c61e5885 Mark George authored on 12 May 2022

Patch

Showing 4 changed files

Ignore Space Show notes View src/client.go
/** Author: Mark George <mark.george@otago.ac.nz> License: Zero-Clause BSD License / package main import ( "fmt" "net/http" "os" "strings" ) type ClientCommand struct { Headers []string `short:"H" long:"header" description:"A header to add to request in the form name:value. Use multiple times for multiple headers."` Method string `short:"m" long:"method" choice:"GET" choice:"POST" choice:"PUT" choice:"DELETE" choice:"PATCH" choice:"HEAD" choice:"OPTIONS" description:"HTTP method for request." default:"GET"` Body string `short:"b" long:"body" description:"Request body to send."` Args struct { URL string } `positional-args:"yes" required:"yes"` } func (opts ClientCommand) Execute(args []string) error { sendRequest(opts) return nil } func sendRequest(opts ClientCommand) { client := http.Client{} request, _ := http.NewRequest(opts.Method, opts.Args.URL, strings.NewReader(opts.Body)) // add extra headers if specified if len(opts.Headers) > 0 { for _, header := range opts.Headers { if name, value, err := parseHeader(header); err == nil { if globalOptions.Verbose { fmt.Println("Adding request header - " + name + ": " + value) } request.Header.Add(name, value) } else { fmt.Println("The following header is not in the correct format: " + header + "\nCorrect format is: 'name:value'") os.Exit(1) } } } if response, err := client.Do(request); err != nil { fmt.Println("Could not connect to server") } else { defer response.Body.Close() showResponse(response) } } /* Author: Mark George <mark.george@otago.ac.nz> License: Zero-Clause BSD License / package main import ( "fmt" "net/http" "os" "strings" ) type ClientCommand struct { Headers []string `short:"H" long:"header" description:"A header to add to request in the form name:value. Use multiple times for multiple headers."` Method string `short:"m" long:"method" choice:"GET" choice:"POST" choice:"PUT" choice:"DELETE" choice:"PATCH" choice:"HEAD" choice:"OPTIONS" description:"HTTP method for request." default:"GET"` Body string `short:"b" long:"body" description:"Request body to send."` URL string `positional-arg-name:"URL" description:"The URL to send the request to." required:"true"` Args struct { URL string } `positional-args:"yes" required:"yes"` } func (opts ClientCommand) Execute(args []string) error { sendRequest(opts) return nil } func sendRequest(opts *ClientCommand) { client := http.Client{} request, _ := http.NewRequest(opts.Method, opts.Args.URL, strings.NewReader(opts.Body)) // add extra headers if specified if len(opts.Headers) > 0 { for _, header := range opts.Headers { if name, value, err := parseHeader(header); err == nil { if globalOptions.Verbose { fmt.Println("Adding request header - " + name + ": " + value) } request.Header.Add(name, value) } else { fmt.Println("The following header is not in the correct format: " + header + "\nCorrect format is: 'name:value'") os.Exit(1) } } } if response, err := client.Do(request); err != nil { fmt.Println("Could not connect to server") } else { defer response.Body.Close() showResponse(response) } }

Ignore Space Show notes View

src/client.go

/**
  Author: Mark George <mark.george@otago.ac.nz>
  License: Zero-Clause BSD License
*/

package main

import (
	"fmt"
	"net/http"
	"os"
	"strings"
)

type ClientCommand struct {
	Headers []string `short:"H" long:"header" description:"A header to add to request in the form name:value. Use multiple times for multiple headers."`
	Method  string   `short:"m" long:"method" choice:"GET" choice:"POST" choice:"PUT" choice:"DELETE" choice:"PATCH" choice:"HEAD" choice:"OPTIONS" description:"HTTP method for request." default:"GET"`
	Body    string   `short:"b" long:"body" description:"Request body to send."`
	Args    struct {
		URL string
	} `positional-args:"yes" required:"yes"`
}

func (opts *ClientCommand) Execute(args []string) error {
	sendRequest(opts)
	return nil
}

func sendRequest(opts *ClientCommand) {

client := http.Client{}

request, _ := http.NewRequest(opts.Method, opts.Args.URL, strings.NewReader(opts.Body))

// add extra headers if specified
	if len(opts.Headers) > 0 {
		for _, header := range opts.Headers {
			if name, value, err := parseHeader(header); err == nil {

if globalOptions.Verbose {
					fmt.Println("Adding request header - " + name + ": " + value)
				}

request.Header.Add(name, value)
			} else {
				fmt.Println("The following header is not in the correct format: " + header + "\nCorrect format is: 'name:value'")
				os.Exit(1)
			}
		}
	}

if response, err := client.Do(request); err != nil {
		fmt.Println("Could not connect to server")
	} else {
		defer response.Body.Close()
		showResponse(response)
	}

}

/**
  Author: Mark George <mark.george@otago.ac.nz>
  License: Zero-Clause BSD License
*/

package main

import (
	"fmt"
	"net/http"
	"os"
	"strings"
)

type ClientCommand struct {
	Headers []string `short:"H" long:"header" description:"A header to add to request in the form name:value. Use multiple times for multiple headers."`
	Method  string   `short:"m" long:"method" choice:"GET" choice:"POST" choice:"PUT" choice:"DELETE" choice:"PATCH" choice:"HEAD" choice:"OPTIONS" description:"HTTP method for request." default:"GET"`
	Body    string   `short:"b" long:"body" description:"Request body to send."`
	URL     string   `positional-arg-name:"URL" description:"The URL to send the request to." required:"true"`
	Args    struct {
		URL string
	} `positional-args:"yes" required:"yes"`
}

func (opts *ClientCommand) Execute(args []string) error {
	sendRequest(opts)
	return nil
}

func sendRequest(opts *ClientCommand) {

client := http.Client{}

request, _ := http.NewRequest(opts.Method, opts.Args.URL, strings.NewReader(opts.Body))

// add extra headers if specified
	if len(opts.Headers) > 0 {
		for _, header := range opts.Headers {
			if name, value, err := parseHeader(header); err == nil {

if globalOptions.Verbose {
					fmt.Println("Adding request header - " + name + ": " + value)
				}

request.Header.Add(name, value)
			} else {
				fmt.Println("The following header is not in the correct format: " + header + "\nCorrect format is: 'name:value'")
				os.Exit(1)
			}
		}
	}

if response, err := client.Do(request); err != nil {
		fmt.Println("Could not connect to server")
	} else {
		defer response.Body.Close()
		showResponse(response)
	}

}

Ignore Space Show notes View src/main.go
/** Author: Mark George <mark.george@otago.ac.nz> License: Zero-Clause BSD License / package main import ( "fmt" "os" "github.com/jessevdk/go-flags" ) const version string = "2.2" type VersionCommand struct{} func (c VersionCommand) Execute(args []string) error { fmt.Println("httpcat v" + version) return nil } func main() { parser := flags.NewParser(globalOptions, flags.Default) parser.AddCommand("client", "Send an HTTP request", "", &ClientCommand{}) parser.AddCommand("server", "Start a mock HTTP server", "", &ServerCommand{}) parser.AddCommand("proxy", "Start a reverse HTTP logging proxy", "", &ProxyCommand{}) parser.AddCommand("version", "Display version", "", &VersionCommand{}) _, err := parser.Parse() if err != nil { parseErr := err.(flags.Error) if parseErr.Type.String() == flags.ErrCommandRequired.String() { os.Stderr.WriteString("\n") parser.WriteHelp(os.Stderr) } } } /* Author: Mark George <mark.george@otago.ac.nz> License: Zero-Clause BSD License / package main import ( "fmt" "os" "github.com/jessevdk/go-flags" ) const version string = "2.1" type VersionCommand struct{} func (c VersionCommand) Execute(args []string) error { fmt.Println("httpcat v" + version) return nil } func main() { parser := flags.NewParser(globalOptions, flags.Default) parser.AddCommand("client", "Send an HTTP request", "", &ClientCommand{}) parser.AddCommand("server", "Start a mock HTTP server", "", &ServerCommand{}) parser.AddCommand("proxy", "Start a reverse HTTP logging proxy", "", &ProxyCommand{}) parser.AddCommand("version", "Display version", "", &VersionCommand{}) _, err := parser.Parse() if err != nil { parseErr := err.(*flags.Error) if parseErr.Type.String() == flags.ErrCommandRequired.String() { os.Stderr.WriteString("\n") parser.WriteHelp(os.Stderr) } } }

Ignore Space Show notes View

src/main.go

Ignore Space Show notes View src/parsing.go
/** Author: Mark George <mark.george@otago.ac.nz> License: Zero-Clause BSD License / package main import ( "errors" "strconv" "strings" ) var ( headers map[string]string = make(map[string]string) bodies map[string]string = make(map[string]string) contentTypes map[string]string = make(map[string]string) statuses map[string]int = make(map[string]int) ) func parseHeader(header string) (string, string, error) { parts := strings.Split(header, ":") if len(parts) < 2 { return "", "", errors.New("header is not in the correct format") } else { name := strings.TrimSpace(parts[0]) value := strings.TrimSpace(parts[1]) // value had a ':' in it (probably a URL) so append the remaining part if len(parts) == 3 { value = value + ":" + strings.TrimSpace(parts[2]) } headers[name] = value return name, value, nil } } func parseRoute(route string) (string, error) { parts := strings.Split(route, "\|") if len(parts) != 4 { return "", errors.New("route is not in the correct format") } else { path := parts[0] body := parts[1] contentType := parts[2] status := parts[3] code, err := strconv.Atoi(status) if err != nil { return "", errors.New("route is not in the correct format") } bodies[path] = body statuses[path] = code contentTypes[path] = contentType return path, nil } } /* Author: Mark George <mark.george@otago.ac.nz> License: Zero-Clause BSD License */ package main import ( "errors" "strconv" "strings" ) var ( headers map[string]string = make(map[string]string) bodies map[string]string = make(map[string]string) statuses map[string]int = make(map[string]int) ) func parseHeader(header string) (string, string, error) { parts := strings.Split(header, ":") if len(parts) < 2 { return "", "", errors.New("header is not in the correct format") } else { name := strings.TrimSpace(parts[0]) value := strings.TrimSpace(parts[1]) // value had a ':' in it (probably a URL) so append the remaining part if len(parts) == 3 { value = value + ":" + strings.TrimSpace(parts[2]) } headers[name] = value return name, value, nil } } func parseRoute(route string) (string, string, int, error) { parts := strings.Split(route, "\|") if len(parts) != 3 { return "", "", 0, errors.New("route is not in the correct format") } else { path := parts[0] body := parts[1] status := parts[2] code, err := strconv.Atoi(status) if err != nil { return "", "", 0, errors.New("route is not in the correct format") } bodies[path] = body statuses[path] = code return path, body, code, nil } }

Ignore Space Show notes View

src/parsing.go

/**
  Author: Mark George <mark.george@otago.ac.nz>
  License: Zero-Clause BSD License
*/

package main

import (
	"errors"
	"strconv"
	"strings"
)

var (
	headers      map[string]string = make(map[string]string)
	bodies       map[string]string = make(map[string]string)
	contentTypes map[string]string = make(map[string]string)
	statuses     map[string]int    = make(map[string]int)
)

func parseHeader(header string) (string, string, error) {

parts := strings.Split(header, ":")

if len(parts) < 2 {
		return "", "", errors.New("header is not in the correct format")
	} else {
		name := strings.TrimSpace(parts[0])
		value := strings.TrimSpace(parts[1])

// value had a ':' in it (probably a URL) so append the remaining part
		if len(parts) == 3 {
			value = value + ":" + strings.TrimSpace(parts[2])
		}

headers[name] = value

return name, value, nil
	}

}

func parseRoute(route string) (string, error) {

parts := strings.Split(route, "|")

if len(parts) != 4 {
		return "", errors.New("route is not in the correct format")
	} else {
		path := parts[0]
		body := parts[1]
		contentType := parts[2]
		status := parts[3]
		code, err := strconv.Atoi(status)
		if err != nil {
			return "", errors.New("route is not in the correct format")
		}

bodies[path] = body
		statuses[path] = code
		contentTypes[path] = contentType

return path, nil
	}

}

/**
  Author: Mark George <mark.george@otago.ac.nz>
  License: Zero-Clause BSD License
*/

package main

import (
	"errors"
	"strconv"
	"strings"
)

var (
	headers  map[string]string = make(map[string]string)
	bodies   map[string]string = make(map[string]string)
	statuses map[string]int    = make(map[string]int)
)

func parseHeader(header string) (string, string, error) {

parts := strings.Split(header, ":")

if len(parts) < 2 {
		return "", "", errors.New("header is not in the correct format")
	} else {
		name := strings.TrimSpace(parts[0])
		value := strings.TrimSpace(parts[1])

// value had a ':' in it (probably a URL) so append the remaining part
		if len(parts) == 3 {
			value = value + ":" + strings.TrimSpace(parts[2])
		}

headers[name] = value

return name, value, nil
	}

}

func parseRoute(route string) (string, string, int, error) {

parts := strings.Split(route, "|")

if len(parts) != 3 {
		return "", "", 0, errors.New("route is not in the correct format")
	} else {
		path := parts[0]
		body := parts[1]
		status := parts[2]
		code, err := strconv.Atoi(status)
		if err != nil {
			return "", "", 0, errors.New("route is not in the correct format")
		}

bodies[path] = body
		statuses[path] = code

return path, body, code, nil
	}

}

Ignore Space Show notes View src/server.go
/** Author: Mark George <mark.george@otago.ac.nz> License: Zero-Clause BSD License / package main import ( "fmt" "net/http" "os" "strconv" ) type ServerCommand struct { Port int `short:"p" long:"port" description:"Port to listen on." default:"8080"` Routes []string `short:"r" long:"route" description:"Add a route which is made up of a path, a response body, a content type, and a response status code, all separated by the pipe '\|' character. Repeat for additional routes. Example '/\|Testing 123\|text/plain\|200'."` Cors bool `short:"c" long:"cors" description:"Enable Cross Origin Resource Sharing (CORS). Allows all requested methods and headers."` Headers []string `short:"H" long:"header" description:"A header to add to response in the form name:value. Use multiple times for multiple headers."` } var ( serverOptions ServerCommand ) func (opts ServerCommand) Execute(args []string) error { serverOptions = opts // parse custom headers if provided if len(opts.Headers) > 0 { for _, header := range opts.Headers { if _, _, err := parseHeader(header); err != nil { fmt.Println("The following header is not in the correct format: " + header + "\nCorrect format is: 'name:value'") os.Exit(1) } } } fmt.Println("HTTP server listening on port " + strconv.Itoa(opts.Port) + "\n") if len(opts.Routes) > 0 { fmt.Println("Routes:") for _, route := range opts.Routes { if path, err := parseRoute(route); err == nil { fmt.Println(" " + path) http.HandleFunc(path, serverRequestHandler) } else { fmt.Println("The following route is not in the correct format: " + route + "\nCorrect format is: \"/path\|response body\|content type\|status code\"") os.Exit(1) } } fmt.Println() } else { // wildcard mode http.HandleFunc("/", serverRequestHandler) } if err := http.ListenAndServe(":"+strconv.Itoa(opts.Port), nil); err != nil { fmt.Fprintf(os.Stderr, "Could not start server. Is port %d available?\n", opts.Port) os.Exit(1) } return nil } func serverRequestHandler(rsp http.ResponseWriter, req http.Request) { path := req.RequestURI body := bodies[path] contentType := contentTypes[path] code := statuses[path] // are we in wildcard mode? if code == 0 && len(statuses) == 0 { if req.Method == http.MethodGet { code = 200 } else { code = 204 } } else if code == 0 { // not in wildcard mode so this is a bad path code = 404 } showRequest(req) // CORS preflight if serverOptions.Cors && req.Method == http.MethodOptions { // was the OPTIONS request actually a CORS request? if secFetchMode := req.Header.Get("Sec-Fetch-Mode"); secFetchMode == "cors" { if globalOptions.Verbose { fmt.Println("Responding to CORS preflight") } if origin := req.Header.Get("Origin"); origin != "" { if globalOptions.Verbose { fmt.Println("Adding CORS response header - Access-Control-Allow-Origin: " + origin) } // allow the origin rsp.Header().Set("Access-Control-Allow-Origin", origin) if headers := req.Header.Get("Access-Control-Request-Headers"); headers != "" { if globalOptions.Verbose { fmt.Println("Adding CORS response header - Access-Control-Allow-Headers: " + headers) } // allow any requested headers rsp.Header().Set("Access-Control-Allow-Headers", headers) } if method := req.Header.Get("Access-Control-Request-Method"); method != "" { if globalOptions.Verbose { fmt.Println("Adding CORS response header - Access-Control-Allow-Methods: " + method) } // allow any requested methods rsp.Header().Set("Access-Control-Allow-Methods", method) } if globalOptions.Verbose { fmt.Println("Adding CORS response header - Access-Control-Max-Age: " + "600") } // allow browser to reuse the permissions for 10 minutes rsp.Header().Set("Access-Control-Max-Age", "600") rsp.WriteHeader(200) return } else { if globalOptions.Verbose { fmt.Println("CORS preflight did not contain 'Origin' header!") } rsp.Header().Set("Content-Type", "text/plain") rsp.WriteHeader(400) fmt.Fprint(rsp, "Origin header was not provided") return } } } // add custom headers if provided if len(serverOptions.Headers) > 0 { for name, value := range headers { if globalOptions.Verbose { fmt.Println("Adding response header - " + name + ": " + value) } rsp.Header().Set(name, value) } } // add CORS allow-origin header if serverOptions.Cors && req.Method != http.MethodOptions { if origin := req.Header.Get("Origin"); origin != "" { if globalOptions.Verbose { fmt.Println("Adding CORS response header - Access-Control-Allow-Origin: " + origin) } rsp.Header().Set("Access-Control-Allow-Origin", origin) } } // add content type if specified if len(contentType) > 0 { rsp.Header().Set("Content-Type", contentType) } // add status line rsp.WriteHeader(code) // add body fmt.Fprint(rsp, body) } /** Author: Mark George <mark.george@otago.ac.nz> License: Zero-Clause BSD License / package main import ( "fmt" "net/http" "os" "strconv" ) type ServerCommand struct { Port int `short:"p" long:"port" description:"Port to listen on." default:"8080"` Routes []string `short:"r" long:"route" description:"Route which is made up of a path, a response body, and a response status, all separated by the pipe '\|' character. Repeat for additional routes."` Cors bool `short:"c" long:"cors" description:"Enable Cross Origin Resource Sharing (CORS). Allows all requested methods and headers."` Headers []string `short:"H" long:"header" description:"A header to add to response in the form name:value. Use multiple times for multiple headers."` } var ( serverOptions ServerCommand ) func (opts ServerCommand) Execute(args []string) error { serverOptions = opts // parse custom headers if provided if len(opts.Headers) > 0 { for _, header := range opts.Headers { if _, _, err := parseHeader(header); err != nil { fmt.Println("The following header is not in the correct format: " + header + "\nCorrect format is: 'name:value'") os.Exit(1) } } } fmt.Println("HTTP server listening on port " + strconv.Itoa(opts.Port) + "\n") if len(opts.Routes) > 0 { fmt.Println("Routes:") for _, route := range opts.Routes { if path, _, _, err := parseRoute(route); err == nil { fmt.Println(" " + path) http.HandleFunc(path, serverRequestHandler) } else { fmt.Println("The following route is not in the correct format: " + route + "\nCorrect format is: \"/path\|response body\|status code\"") os.Exit(1) } } fmt.Println() } else { // wildcard mode http.HandleFunc("/", serverRequestHandler) } if err := http.ListenAndServe(":"+strconv.Itoa(opts.Port), nil); err != nil { fmt.Fprintf(os.Stderr, "Could not start server. Is port %d available?\n", opts.Port) os.Exit(1) } return nil } func serverRequestHandler(rsp http.ResponseWriter, req http.Request) { path := req.RequestURI body := bodies[path] code := statuses[path] // are we in wildcard mode? if code == 0 && len(statuses) == 0 { if req.Method == http.MethodGet { code = 200 } else { code = 204 } } else if code == 0 { // not in wildcard mode so this is a bad path code = 404 } showRequest(req) // CORS preflight if serverOptions.Cors && req.Method == http.MethodOptions { // was the OPTIONS request actually a CORS request? if secFetchMode := req.Header.Get("Sec-Fetch-Mode"); secFetchMode == "cors" { if globalOptions.Verbose { fmt.Println("Responding to CORS preflight") } if origin := req.Header.Get("Origin"); origin != "" { if globalOptions.Verbose { fmt.Println("Adding CORS response header - Access-Control-Allow-Origin: " + origin) } // allow the origin rsp.Header().Set("Access-Control-Allow-Origin", origin) if headers := req.Header.Get("Access-Control-Request-Headers"); headers != "" { if globalOptions.Verbose { fmt.Println("Adding CORS response header - Access-Control-Allow-Headers: " + headers) } // allow any requested headers rsp.Header().Set("Access-Control-Allow-Headers", headers) } if method := req.Header.Get("Access-Control-Request-Method"); method != "" { if globalOptions.Verbose { fmt.Println("Adding CORS response header - Access-Control-Allow-Methods: " + method) } // allow any requested methods rsp.Header().Set("Access-Control-Allow-Methods", method) } if globalOptions.Verbose { fmt.Println("Adding CORS response header - Access-Control-Max-Age: " + "600") } // allow browser to reuse the permissions for 10 minutes rsp.Header().Set("Access-Control-Max-Age", "600") rsp.WriteHeader(200) return } else { if globalOptions.Verbose { fmt.Println("CORS preflight did not contain 'Origin' header!") } rsp.Header().Set("Content-Type", "text/plain") rsp.WriteHeader(400) fmt.Fprint(rsp, "Origin header was not provided") return } } } // add custom headers if provided if len(serverOptions.Headers) > 0 { for name, value := range headers { if globalOptions.Verbose { fmt.Println("Adding response header - " + name + ": " + value) } rsp.Header().Set(name, value) } } // add CORS allow-origin header if serverOptions.Cors && req.Method != http.MethodOptions { if origin := req.Header.Get("Origin"); origin != "" { if globalOptions.Verbose { fmt.Println("Adding CORS response header - Access-Control-Allow-Origin: " + origin) } rsp.Header().Set("Access-Control-Allow-Origin", origin) } } // add status line rsp.WriteHeader(code) // add body fmt.Fprint(rsp, body) }

Ignore Space Show notes View

src/server.go

/**
  Author: Mark George <mark.george@otago.ac.nz>
  License: Zero-Clause BSD License
*/

package main

import (
	"fmt"
	"net/http"
	"os"
	"strconv"
)

type ServerCommand struct {
	Port    int      `short:"p" long:"port" description:"Port to listen on." default:"8080"`
	Routes  []string `short:"r" long:"route" description:"Add a route which is made up of a path, a response body, a content type, and a response status code, all separated by the pipe '|' character.  Repeat for additional routes.  Example '/|Testing 123|text/plain|200'."`
	Cors    bool     `short:"c" long:"cors" description:"Enable Cross Origin Resource Sharing (CORS).  Allows all requested methods and headers."`
	Headers []string `short:"H" long:"header" description:"A header to add to response in the form name:value. Use multiple times for multiple headers."`
}

var (
	serverOptions *ServerCommand
)

func (opts *ServerCommand) Execute(args []string) error {

serverOptions = opts

// parse custom headers if provided
	if len(opts.Headers) > 0 {
		for _, header := range opts.Headers {
			if _, _, err := parseHeader(header); err != nil {
				fmt.Println("The following header is not in the correct format: " + header + "\nCorrect format is: 'name:value'")
				os.Exit(1)
			}
		}
	}

fmt.Println("HTTP server listening on port " + strconv.Itoa(opts.Port) + "\n")

if len(opts.Routes) > 0 {
		fmt.Println("Routes:")
		for _, route := range opts.Routes {
			if path, err := parseRoute(route); err == nil {
				fmt.Println("  " + path)
				http.HandleFunc(path, serverRequestHandler)
			} else {
				fmt.Println("The following route is not in the correct format: " + route + "\nCorrect format is: \"/path|response body|content type|status code\"")
				os.Exit(1)
			}
		}
		fmt.Println()
	} else {
		// wildcard mode
		http.HandleFunc("/", serverRequestHandler)
	}

if err := http.ListenAndServe(":"+strconv.Itoa(opts.Port), nil); err != nil {
		fmt.Fprintf(os.Stderr, "Could not start server.  Is port %d available?\n", opts.Port)
		os.Exit(1)
	}

return nil
}

func serverRequestHandler(rsp http.ResponseWriter, req *http.Request) {

path := req.RequestURI
	body := bodies[path]
	contentType := contentTypes[path]
	code := statuses[path]

// are we in wildcard mode?
	if code == 0 && len(statuses) == 0 {
		if req.Method == http.MethodGet {
			code = 200
		} else {
			code = 204
		}
	} else if code == 0 {
		// not in wildcard mode so this is a bad path
		code = 404
	}

showRequest(req)

// CORS preflight
	if serverOptions.Cors && req.Method == http.MethodOptions {

// was the OPTIONS request actually a CORS request?
		if secFetchMode := req.Header.Get("Sec-Fetch-Mode"); secFetchMode == "cors" {

if globalOptions.Verbose {
				fmt.Println("Responding to CORS preflight")
			}

if origin := req.Header.Get("Origin"); origin != "" {

if globalOptions.Verbose {
					fmt.Println("Adding CORS response header - Access-Control-Allow-Origin: " + origin)
				}

// allow the origin
				rsp.Header().Set("Access-Control-Allow-Origin", origin)

if headers := req.Header.Get("Access-Control-Request-Headers"); headers != "" {

if globalOptions.Verbose {
						fmt.Println("Adding CORS response header - Access-Control-Allow-Headers: " + headers)
					}

// allow any requested headers
					rsp.Header().Set("Access-Control-Allow-Headers", headers)
				}

if method := req.Header.Get("Access-Control-Request-Method"); method != "" {
					if globalOptions.Verbose {
						fmt.Println("Adding CORS response header - Access-Control-Allow-Methods: " + method)
					}
					// allow any requested methods
					rsp.Header().Set("Access-Control-Allow-Methods", method)
				}

if globalOptions.Verbose {
					fmt.Println("Adding CORS response header - Access-Control-Max-Age: " + "600")
				}
				// allow browser to reuse the permissions for 10 minutes
				rsp.Header().Set("Access-Control-Max-Age", "600")

rsp.WriteHeader(200)

return

} else {
				if globalOptions.Verbose {
					fmt.Println("CORS preflight did not contain 'Origin' header!")
				}
				rsp.Header().Set("Content-Type", "text/plain")
				rsp.WriteHeader(400)
				fmt.Fprint(rsp, "Origin header was not provided")

return
			}
		}

}

// add custom headers if provided
	if len(serverOptions.Headers) > 0 {

for name, value := range headers {

if globalOptions.Verbose {
				fmt.Println("Adding response header - " + name + ": " + value)
			}

rsp.Header().Set(name, value)
		}
	}

// add CORS allow-origin header
	if serverOptions.Cors && req.Method != http.MethodOptions {
		if origin := req.Header.Get("Origin"); origin != "" {
			if globalOptions.Verbose {
				fmt.Println("Adding CORS response header - Access-Control-Allow-Origin: " + origin)
			}
			rsp.Header().Set("Access-Control-Allow-Origin", origin)
		}
	}

// add content type if specified
	if len(contentType) > 0 {
		rsp.Header().Set("Content-Type", contentType)
	}

// add status line
	rsp.WriteHeader(code)

// add body
	fmt.Fprint(rsp, body)
}

/**
  Author: Mark George <mark.george@otago.ac.nz>
  License: Zero-Clause BSD License
*/

package main

import (
	"fmt"
	"net/http"
	"os"
	"strconv"
)

type ServerCommand struct {
	Port    int      `short:"p" long:"port" description:"Port to listen on." default:"8080"`
	Routes  []string `short:"r" long:"route" description:"Route which is made up of a path, a response body, and a response status, all separated by the pipe '|' character.  Repeat for additional routes."`
	Cors    bool     `short:"c" long:"cors" description:"Enable Cross Origin Resource Sharing (CORS).  Allows all requested methods and headers."`
	Headers []string `short:"H" long:"header" description:"A header to add to response in the form name:value. Use multiple times for multiple headers."`
}

var (
	serverOptions *ServerCommand
)

func (opts *ServerCommand) Execute(args []string) error {

serverOptions = opts

fmt.Println("HTTP server listening on port " + strconv.Itoa(opts.Port) + "\n")

if len(opts.Routes) > 0 {
		fmt.Println("Routes:")
		for _, route := range opts.Routes {
			if path, _, _, err := parseRoute(route); err == nil {
				fmt.Println("  " + path)
				http.HandleFunc(path, serverRequestHandler)
			} else {
				fmt.Println("The following route is not in the correct format: " + route + "\nCorrect format is: \"/path|response body|status code\"")
				os.Exit(1)
			}
		}
		fmt.Println()
	} else {
		// wildcard mode
		http.HandleFunc("/", serverRequestHandler)
	}

if err := http.ListenAndServe(":"+strconv.Itoa(opts.Port), nil); err != nil {
		fmt.Fprintf(os.Stderr, "Could not start server.  Is port %d available?\n", opts.Port)
		os.Exit(1)
	}

return nil
}

func serverRequestHandler(rsp http.ResponseWriter, req *http.Request) {

path := req.RequestURI
	body := bodies[path]
	code := statuses[path]

showRequest(req)

// CORS preflight
	if serverOptions.Cors && req.Method == http.MethodOptions {

// was the OPTIONS request actually a CORS request?
		if secFetchMode := req.Header.Get("Sec-Fetch-Mode"); secFetchMode == "cors" {

if globalOptions.Verbose {
				fmt.Println("Responding to CORS preflight")
			}

if origin := req.Header.Get("Origin"); origin != "" {

if globalOptions.Verbose {
					fmt.Println("Adding CORS response header - Access-Control-Allow-Origin: " + origin)
				}

// allow the origin
				rsp.Header().Set("Access-Control-Allow-Origin", origin)

if headers := req.Header.Get("Access-Control-Request-Headers"); headers != "" {

if globalOptions.Verbose {
						fmt.Println("Adding CORS response header - Access-Control-Allow-Headers: " + headers)
					}

// allow any requested headers
					rsp.Header().Set("Access-Control-Allow-Headers", headers)
				}

rsp.WriteHeader(200)

return

return
			}
		}

}

// add custom headers if provided
	if len(serverOptions.Headers) > 0 {

for name, value := range headers {

if globalOptions.Verbose {
				fmt.Println("Adding response header - " + name + ": " + value)
			}

rsp.Header().Set(name, value)
		}
	}

// add status line
	rsp.WriteHeader(code)

// add body
	fmt.Fprint(rsp, body)
}

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