Alteration for version passing

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

.gitignore

@@ -2,3 +2,6 @@
 hosts
 /resolv.conf
 .idea/
+
+basic-auth-user
+basic-auth-password

Gopkg.lock

@@ -273,6 +273,14 @@
   revision = "ba968bfe8b2f7e042a574c888954fccecfa385b4"
   version = "v0.8.1"
 
+[[projects]]
+  digest = "1:044c51736e2688a3e4f28f72537f8a7b3f9c188fab4477d5334d92dfe2c07ed5"
+  name = "github.com/sethvargo/go-password"
+  packages = ["password"]
+  pruneopts = "UT"
+  revision = "07c3d521e892540e71469bb0312866130714c038"
+  version = "v0.1.3"
+
 [[projects]]
   digest = "1:fd61cf4ae1953d55df708acb6b91492d538f49c305b364a014049914495db426"
   name = "github.com/sirupsen/logrus"
@@ -466,6 +474,7 @@
     "github.com/containerd/containerd/oci",
     "github.com/morikuni/aec",
     "github.com/opencontainers/runtime-spec/specs-go",
+    "github.com/sethvargo/go-password/password",
     "github.com/spf13/cobra",
     "github.com/vishvananda/netlink",
     "github.com/vishvananda/netns",

Gopkg.toml

@@ -21,3 +21,7 @@
 [prune]
   go-tests = true
   unused-packages = true
+
+[[constraint]]
+  name = "github.com/sethvargo/go-password"
+  version = "0.1.3"

Makefile

@@ -1,6 +1,6 @@
 Version := $(shell git describe --tags --dirty)
 GitCommit := $(shell git rev-parse HEAD)
-LDFLAGS := "-s -w -X pkg.Version=$(Version) -X pkg.GitCommit=$(GitCommit)"
+LDFLAGS := "-s -w -X main.Version=$(Version) -X main.GitCommit=$(GitCommit)"
 
 .PHONY: all
 all: local

README.md

@@ -40,7 +40,6 @@ Other operations are pending development in the provider.
 
 Pending:
 
-* [ ] Configure `basic_auth` to protect the OpenFaaS gateway and faas-containerd HTTP API
 * [ ] Use CNI to create network namespaces and adapters
 * [ ] Monitor and restart any of the core components at runtime if the container stops
 * [ ] Bundle/package/automate installation of containerd - [see bootstrap from k3s](https://github.com/rancher/k3s)
@@ -55,6 +54,7 @@ Done:
 * [x] Restart containers upon restart of faasd
 * [x] Clear / remove containers and tasks with SIGTERM / SIGINT
 * [x] Determine armhf/arm64 containers to run for gateway
+* [x] Configure `basic_auth` to protect the OpenFaaS gateway and faas-containerd HTTP API
 
 ## Hacking (build from source)
 
@@ -86,17 +86,17 @@ go build
 
 ```sh
 # For x86_64
-sudo curl -fSLs "https://github.com/alexellis/faasd/releases/download/0.2.5/faasd" \
+sudo curl -fSLs "https://github.com/alexellis/faasd/releases/download/0.3.1/faasd" \
     -o "/usr/local/bin/faasd" \
     && sudo chmod a+x "/usr/local/bin/faasd"
 
 # armhf
-sudo curl -fSLs "https://github.com/alexellis/faasd/releases/download/0.2.5/faasd-armhf" \
+sudo curl -fSLs "https://github.com/alexellis/faasd/releases/download/0.3.1/faasd-armhf" \
     -o "/usr/local/bin/faasd" \
     && sudo chmod a+x "/usr/local/bin/faasd"
 
 # arm64
-sudo curl -fSLs "https://github.com/alexellis/faasd/releases/download/0.2.5/faasd-arm64" \
+sudo curl -fSLs "https://github.com/alexellis/faasd/releases/download/0.3.1/faasd-arm64" \
     -o "/usr/local/bin/faasd" \
     && sudo chmod a+x "/usr/local/bin/faasd"
 ```
@@ -123,6 +123,11 @@ Since faas-containerd uses containerd heavily it is not running as a container,
 
 * Now go to the gateway's IP address as shown above on port 8080, i.e. http://172.19.0.3:8080 - you can also use this address to deploy OpenFaaS Functions via the `faas-cli`. 
 
+* basic-auth
+
+    You will then need to get the basic-auth password, it is written to `$GOPATH/src/github.com/alexellis/faasd/basic-auth-password` if you followed the above instructions.
+The default Basic Auth username is `admin`, which is written to `$GOPATH/src/github.com/alexellis/faasd/basic-auth-user`, if you wish to use a non-standard user then create this file and add your username (no newlines or other characters) 
+
 #### Installation with systemd
 
 * `faasd install` - install faasd and containerd with systemd, run in `$GOPATH/src/github.com/alexellis/faasd`

cmd/root.go

@@ -3,19 +3,10 @@ package cmd
 import (
 	"fmt"
 
-	"github.com/alexellis/faasd/pkg"
 	"github.com/morikuni/aec"
 	"github.com/spf13/cobra"
 )
 
-var (
-	// Version as per git repo
-	Version string
-
-	// GitCommit as per git repo
-	GitCommit string
-)
-
 // WelcomeMessage to introduce ofc-bootstrap
 const WelcomeMessage = "Welcome to faasd"
 
@@ -25,39 +16,14 @@ func init() {
 	rootCommand.AddCommand(installCmd)
 }
 
-var rootCommand = &cobra.Command{
-	Use:   "faasd",
-	Short: "Start faasd",
-	Long: `
-faasd - serverless without Kubernetes
-`,
-	RunE:         runRootCommand,
-	SilenceUsage: true,
-}
-
-var versionCmd = &cobra.Command{
-	Use:   "version",
-	Short: "Display version information.",
-	Run:   parseBaseCommand,
-}
-
-func getVersion() string {
-	if len(Version) != 0 {
-		return Version
-	}
-	return "dev"
-}
-
-func parseBaseCommand(_ *cobra.Command, _ []string) {
-	printLogo()
-
-	fmt.Printf(
-		`faasd
-Commit: %s
-Version: %s
-`, pkg.GitCommit, pkg.GetVersion())
-}
+var (
+	// GitCommit Git Commit SHA
+	GitCommit string
+	// Version version of the CLI
+	Version string
+)
 
+// Execute faasd
 func Execute(version, gitCommit string) error {
 
 	// Get Version and GitCommit values from main.go.
@@ -70,6 +36,16 @@ func Execute(version, gitCommit string) error {
 	return nil
 }
 
+var rootCommand = &cobra.Command{
+	Use:   "faasd",
+	Short: "Start faasd",
+	Long: `
+faasd - serverless without Kubernetes
+`,
+	RunE:         runRootCommand,
+	SilenceUsage: true,
+}
+
 func runRootCommand(cmd *cobra.Command, args []string) error {
 
 	printLogo()
@@ -78,7 +54,39 @@ func runRootCommand(cmd *cobra.Command, args []string) error {
 	return nil
 }
 
+var versionCmd = &cobra.Command{
+	Use:   "version",
+	Short: "Display version information.",
+	Run:   parseBaseCommand,
+}
+
+func parseBaseCommand(_ *cobra.Command, _ []string) {
+	printLogo()
+
+	fmt.Printf(
+		`faasd
+Commit: %s
+Version: %s
+`, GitCommit, GetVersion())
+}
+
 func printLogo() {
-	logoText := aec.WhiteF.Apply(pkg.Logo)
+	logoText := aec.WhiteF.Apply(Logo)
 	fmt.Println(logoText)
 }
+
+// GetVersion get latest version
+func GetVersion() string {
+	if len(Version) == 0 {
+		return "dev"
+	}
+	return Version
+}
+
+// Logo for version and root command
+const Logo = `  __                     _ 
+ / _| __ _  __ _ ___  __| |
+| |_ / _` + "`" + ` |/ _` + "`" + ` / __|/ _` + "`" + ` |
+|  _| (_| | (_| \__ \ (_| |
+|_|  \__,_|\__,_|___/\__,_|
+`

cmd/up.go

@@ -2,6 +2,8 @@ package cmd
 
 import (
 	"fmt"
+	"github.com/pkg/errors"
+	"io/ioutil"
 	"log"
 	"os"
 	"os/signal"
@@ -12,6 +14,7 @@ import (
 
 	"github.com/alexellis/faasd/pkg"
 	"github.com/alexellis/k3sup/pkg/env"
+	"github.com/sethvargo/go-password/password"
 	"github.com/spf13/cobra"
 )
 
@@ -42,6 +45,11 @@ func runUp(_ *cobra.Command, _ []string) error {
 		clientSuffix = "-arm64"
 	}
 
+	authFileErr := errors.Wrap(makeBasicAuthFiles(), "Could not create gateway auth files")
+	if authFileErr != nil {
+		return authFileErr
+	}
+
 	services := makeServiceDefinitions(clientSuffix)
 
 	start := time.Now()
@@ -96,10 +104,70 @@ func runUp(_ *cobra.Command, _ []string) error {
 	return nil
 }
 
+func makeBasicAuthFiles() error {
+	wd, _ := os.Getwd()
+	pwdFile := wd + "/basic-auth-password"
+	authPassword, err := password.Generate(63, 10, 0, false, true)
+
+	if err != nil {
+		return err
+	}
+
+	err = makeFile(pwdFile, authPassword)
+	if err != nil {
+		return err
+	}
+
+	userFile := wd + "/basic-auth-user"
+	err = makeFile(userFile, "admin")
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func makeFile(filePath, fileContents string) error {
+	_, err := os.Stat(filePath)
+	if err == nil {
+		log.Printf("File exists: %q, Using data from this file",filePath)
+		return nil
+	} else if os.IsNotExist(err) {
+		log.Printf("Writing file: %q", filePath)
+		return ioutil.WriteFile(filePath, []byte(fileContents), 0644)
+	} else {
+		return err
+	}
+}
+
 func makeServiceDefinitions(archSuffix string) []pkg.Service {
 	wd, _ := os.Getwd()
 
+	secretMountDir := "/run/secrets/"
+
 	return []pkg.Service{
+		pkg.Service{
+			Name:   "basic-auth-plugin",
+			Image:  "docker.io/openfaas/basic-auth-plugin:0.18.10" + archSuffix,
+			Env: []string{
+				"port=8080",
+				"secret_mount_path=" + secretMountDir,
+				"user_filename=basic-auth-user",
+				"pass_filename=basic-auth-password",
+			},
+			Mounts: []pkg.Mount{
+				pkg.Mount{
+					Src:path.Join(wd, "/basic-auth-password"),
+					Dest:secretMountDir + "basic-auth-password",
+				},
+				pkg.Mount{
+					Src:  path.Join(wd, "/basic-auth-user"),
+					Dest: secretMountDir + "basic-auth-user",
+				},
+			},
+			Caps: []string{"CAP_NET_RAW"},
+			Args:   nil,
+		},
 		pkg.Service{
 			Name:  "nats",
 			Env:   []string{""},
@@ -122,7 +190,7 @@ func makeServiceDefinitions(archSuffix string) []pkg.Service {
 		pkg.Service{
 			Name: "gateway",
 			Env: []string{
-				"basic_auth=false",
+				"basic_auth=true",
 				"functions_provider_url=http://faas-containerd:8081/",
 				"direct_functions=false",
 				"read_timeout=60s",
@@ -130,9 +198,21 @@ func makeServiceDefinitions(archSuffix string) []pkg.Service {
 				"upstream_timeout=65s",
 				"faas_nats_address=nats",
 				"faas_nats_port=4222",
+				"auth_proxy_url=http://basic-auth-plugin:8080/validate",
+				"auth_proxy_pass_body=false",
+				"secret_mount_path=" + secretMountDir,
 			},
 			Image:  "docker.io/openfaas/gateway:0.18.8" + archSuffix,
-			Mounts: []pkg.Mount{},
+			Mounts: []pkg.Mount{
+				pkg.Mount{
+					Src:path.Join(wd, "/basic-auth-password"),
+					Dest:secretMountDir + "basic-auth-password",
+				},
+				pkg.Mount{
+					Src:  path.Join(wd, "/basic-auth-user"),
+					Dest: secretMountDir + "basic-auth-user",
+				},
+			},
 			Caps:   []string{"CAP_NET_RAW"},
 		},
 		pkg.Service{
@@ -145,9 +225,20 @@ func makeServiceDefinitions(archSuffix string) []pkg.Service {
 				"ack_wait=5m5s",
 				"max_inflight=1",
 				"write_debug=false",
+				"basic_auth=true",
+				"secret_mount_path=" + secretMountDir,
 			},
 			Image:  "docker.io/openfaas/queue-worker:0.9.0",
-			Mounts: []pkg.Mount{},
+			Mounts: []pkg.Mount{
+				pkg.Mount{
+					Src:path.Join(wd, "/basic-auth-password"),
+					Dest:secretMountDir + "basic-auth-password",
+				},
+				pkg.Mount{
+					Src:  path.Join(wd, "/basic-auth-user"),
+					Dest: secretMountDir + "basic-auth-user",
+				},
+			},
 			Caps:   []string{"CAP_NET_RAW"},
 		},
 	}

main.go

@@ -4,13 +4,19 @@ import (
 	"os"
 
 	"github.com/alexellis/faasd/cmd"
-	"github.com/alexellis/faasd/pkg"
+)
+
+// These values will be injected into these variables at the build time.
+var (
+	// GitCommit Git Commit SHA
+	GitCommit string
+	// Version version of the CLI
+	Version string
 )
 
 func main() {
-	if err := cmd.Execute(pkg.Version, pkg.GitCommit); err != nil {
+	if err := cmd.Execute(Version, GitCommit); err != nil {
 		os.Exit(1)
 	}
 	return
-
 }

pkg/proxy.go

@@ -63,7 +63,7 @@ func (p *Proxy) Start() error {
 			}
 
 			upstream := fmt.Sprintf("http://%s:8080%s%s", data.host, r.URL.Path, query)
-			fmt.Printf("Forward to %s %s\n", upstream, data)
+			fmt.Printf("[faasd] proxy: %s\n", upstream)
 
 			if r.Body != nil {
 				defer r.Body.Close()

pkg/version.go

@@ -1,23 +1 @@
 package pkg
-
-var (
-	//GitCommit Git Commit SHA
-	GitCommit string
-	//Version version of the CLI
-	Version string
-)
-
-//GetVersion get latest version
-func GetVersion() string {
-	if len(Version) == 0 {
-		return "dev"
-	}
-	return Version
-}
-
-const Logo = `  __                     _ 
- / _| __ _  __ _ ___  __| |
-| |_ / _` + "`" + ` |/ _` + "`" + ` / __|/ _` + "`" + ` |
-|  _| (_| | (_| \__ \ (_| |
-|_|  \__,_|\__,_|___/\__,_|
-`

vendor/github.com/sethvargo/go-password/LICENSE

@@ -0,0 +1,20 @@
+Copyright 2017 Seth Vargo <seth@sethvargo.com>
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

vendor/github.com/sethvargo/go-password/password/generate.go

@@ -0,0 +1,253 @@
+// Package password provides a library for generating high-entropy random
+// password strings via the crypto/rand package.
+//
+//    res, err := Generate(64, 10, 10, false, false)
+//    if err != nil  {
+//      log.Fatal(err)
+//    }
+//    log.Printf(res)
+//
+// Most functions are safe for concurrent use.
+package password
+
+import (
+	"crypto/rand"
+	"errors"
+	"math/big"
+	"strings"
+)
+
+// Built-time checks that the generators implement the interface.
+var _ PasswordGenerator = (*Generator)(nil)
+
+// PasswordGenerator is an interface that implements the Generate function. This
+// is useful for testing where you can pass this interface instead of a real
+// password generator to mock responses for predicability.
+type PasswordGenerator interface {
+	Generate(int, int, int, bool, bool) (string, error)
+	MustGenerate(int, int, int, bool, bool) string
+}
+
+const (
+	// LowerLetters is the list of lowercase letters.
+	LowerLetters = "abcdefghijklmnopqrstuvwxyz"
+
+	// UpperLetters is the list of uppercase letters.
+	UpperLetters = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+
+	// Digits is the list of permitted digits.
+	Digits = "0123456789"
+
+	// Symbols is the list of symbols.
+	Symbols = "~!@#$%^&*()_+`-={}|[]\\:\"<>?,./"
+)
+
+var (
+	// ErrExceedsTotalLength is the error returned with the number of digits and
+	// symbols is greater than the total length.
+	ErrExceedsTotalLength = errors.New("number of digits and symbols must be less than total length")
+
+	// ErrLettersExceedsAvailable is the error returned with the number of letters
+	// exceeds the number of available letters and repeats are not allowed.
+	ErrLettersExceedsAvailable = errors.New("number of letters exceeds available letters and repeats are not allowed")
+
+	// ErrDigitsExceedsAvailable is the error returned with the number of digits
+	// exceeds the number of available digits and repeats are not allowed.
+	ErrDigitsExceedsAvailable = errors.New("number of digits exceeds available digits and repeats are not allowed")
+
+	// ErrSymbolsExceedsAvailable is the error returned with the number of symbols
+	// exceeds the number of available symbols and repeats are not allowed.
+	ErrSymbolsExceedsAvailable = errors.New("number of symbols exceeds available symbols and repeats are not allowed")
+)
+
+// Generator is the stateful generator which can be used to customize the list
+// of letters, digits, and/or symbols.
+type Generator struct {
+	lowerLetters string
+	upperLetters string
+	digits       string
+	symbols      string
+}
+
+// GeneratorInput is used as input to the NewGenerator function.
+type GeneratorInput struct {
+	LowerLetters string
+	UpperLetters string
+	Digits       string
+	Symbols      string
+}
+
+// NewGenerator creates a new Generator from the specified configuration. If no
+// input is given, all the default values are used. This function is safe for
+// concurrent use.
+func NewGenerator(i *GeneratorInput) (*Generator, error) {
+	if i == nil {
+		i = new(GeneratorInput)
+	}
+
+	g := &Generator{
+		lowerLetters: i.LowerLetters,
+		upperLetters: i.UpperLetters,
+		digits:       i.Digits,
+		symbols:      i.Symbols,
+	}
+
+	if g.lowerLetters == "" {
+		g.lowerLetters = LowerLetters
+	}
+
+	if g.upperLetters == "" {
+		g.upperLetters = UpperLetters
+	}
+
+	if g.digits == "" {
+		g.digits = Digits
+	}
+
+	if g.symbols == "" {
+		g.symbols = Symbols
+	}
+
+	return g, nil
+}
+
+// Generate generates a password with the given requirements. length is the
+// total number of characters in the password. numDigits is the number of digits
+// to include in the result. numSymbols is the number of symbols to include in
+// the result. noUpper excludes uppercase letters from the results. allowRepeat
+// allows characters to repeat.
+//
+// The algorithm is fast, but it's not designed to be performant; it favors
+// entropy over speed. This function is safe for concurrent use.
+func (g *Generator) Generate(length, numDigits, numSymbols int, noUpper, allowRepeat bool) (string, error) {
+	letters := g.lowerLetters
+	if !noUpper {
+		letters += g.upperLetters
+	}
+
+	chars := length - numDigits - numSymbols
+	if chars < 0 {
+		return "", ErrExceedsTotalLength
+	}
+
+	if !allowRepeat && chars > len(letters) {
+		return "", ErrLettersExceedsAvailable
+	}
+
+	if !allowRepeat && numDigits > len(g.digits) {
+		return "", ErrDigitsExceedsAvailable
+	}
+
+	if !allowRepeat && numSymbols > len(g.symbols) {
+		return "", ErrSymbolsExceedsAvailable
+	}
+
+	var result string
+
+	// Characters
+	for i := 0; i < chars; i++ {
+		ch, err := randomElement(letters)
+		if err != nil {
+			return "", err
+		}
+
+		if !allowRepeat && strings.Contains(result, ch) {
+			i--
+			continue
+		}
+
+		result, err = randomInsert(result, ch)
+		if err != nil {
+			return "", err
+		}
+	}
+
+	// Digits
+	for i := 0; i < numDigits; i++ {
+		d, err := randomElement(g.digits)
+		if err != nil {
+			return "", err
+		}
+
+		if !allowRepeat && strings.Contains(result, d) {
+			i--
+			continue
+		}
+
+		result, err = randomInsert(result, d)
+		if err != nil {
+			return "", err
+		}
+	}
+
+	// Symbols
+	for i := 0; i < numSymbols; i++ {
+		sym, err := randomElement(g.symbols)
+		if err != nil {
+			return "", err
+		}
+
+		if !allowRepeat && strings.Contains(result, sym) {
+			i--
+			continue
+		}
+
+		result, err = randomInsert(result, sym)
+		if err != nil {
+			return "", err
+		}
+	}
+
+	return result, nil
+}
+
+// MustGenerate is the same as Generate, but panics on error.
+func (g *Generator) MustGenerate(length, numDigits, numSymbols int, noUpper, allowRepeat bool) string {
+	res, err := g.Generate(length, numDigits, numSymbols, noUpper, allowRepeat)
+	if err != nil {
+		panic(err)
+	}
+	return res
+}
+
+// Generate is the package shortcut for Generator.Generate.
+func Generate(length, numDigits, numSymbols int, noUpper, allowRepeat bool) (string, error) {
+	gen, err := NewGenerator(nil)
+	if err != nil {
+		return "", err
+	}
+
+	return gen.Generate(length, numDigits, numSymbols, noUpper, allowRepeat)
+}
+
+// MustGenerate is the package shortcut for Generator.MustGenerate.
+func MustGenerate(length, numDigits, numSymbols int, noUpper, allowRepeat bool) string {
+	res, err := Generate(length, numDigits, numSymbols, noUpper, allowRepeat)
+	if err != nil {
+		panic(err)
+	}
+	return res
+}
+
+// randomInsert randomly inserts the given value into the given string.
+func randomInsert(s, val string) (string, error) {
+	if s == "" {
+		return val, nil
+	}
+
+	n, err := rand.Int(rand.Reader, big.NewInt(int64(len(s)+1)))
+	if err != nil {
+		return "", err
+	}
+	i := n.Int64()
+	return s[0:i] + val + s[i:], nil
+}
+
+// randomElement extracts a random element from the given string.
+func randomElement(s string) (string, error) {
+	n, err := rand.Int(rand.Reader, big.NewInt(int64(len(s))))
+	if err != nil {
+		return "", err
+	}
+	return string(s[n.Int64()]), nil
+}

vendor/github.com/sethvargo/go-password/password/mock.go

@@ -0,0 +1,39 @@
+package password
+
+// Built-time checks that the generators implement the interface.
+var _ PasswordGenerator = (*mockGenerator)(nil)
+
+type mockGenerator struct {
+	result string
+	err    error
+}
+
+// NewMockGenerator creates a new generator that satisfies the PasswordGenerator
+// interface. If an error is provided, the error is returned. If a result if
+// provided, the result is always returned, regardless of what parameters are
+// passed into the Generate or MustGenerate methods.
+//
+// This function is most useful for tests where you want to have predicable
+// results for a transitive resource that depends on go-password.
+func NewMockGenerator(result string, err error) *mockGenerator {
+	return &mockGenerator{
+		result: result,
+		err:    err,
+	}
+}
+
+// Generate returns the mocked result or error.
+func (g *mockGenerator) Generate(int, int, int, bool, bool) (string, error) {
+	if g.err != nil {
+		return "", g.err
+	}
+	return g.result, nil
+}
+
+// MustGenerate returns the mocked result or panics if an error was given.
+func (g *mockGenerator) MustGenerate(int, int, int, bool, bool) string {
+	if g.err != nil {
+		panic(g.err)
+	}
+	return g.result
+}