fix: replace moby/moby namesgenerator with internal implementation (#21377)

Replace the external moby/moby/pkg/namesgenerator dependency with an
internal implementation using gofakeit/v7. The moby package has ~25k
unique name combinations, and with its retry parameter only adds a
random digit 0-9, giving ~250k possibilities. In parallel tests, this
has led to collisions (flakes).

The new internal API at coderd/util/namesgenerator eliminates the
external dependnecy and offers functions with explicit uniqueness
guarantees. This PR also consolidates fragmented name generation in a
few places to use the new package.

| Old (moby/moby)                     | New                    |
|-------------------------------------|------------------------|
| namesgenerator.GetRandomName(0)     | NameWith("_")          |
| namesgenerator.GetRandomName(>0)    | NameDigitWith("_")     |
| testutil.GetRandomName(t)           | UniqueName()           |
| testutil.GetRandomNameHyphenated(t) | UniqueNameWith("-")    |

namesgenerator package API:
- NameWith(delim): random name, not unique
- NameDigitWith(delim): random name with 1-9 suffix, not unique
- UniqueName(): guaranteed unique via atomic counter
- UniqueNameWith(delim): unique with custom delimiter

Names continue to be docker style `[adjective][delim][surname]`. Unique
names are truncated to 32 characters (preserving the numeric suffix) to
fit common name length limits in Coder.

Related test flakes:
https://github.com/coder/internal/issues/1212
https://github.com/coder/internal/issues/118
https://github.com/coder/internal/issues/1068

coderd/apikey.go

@@ -9,7 +9,6 @@ import (
 
 	"github.com/go-chi/chi/v5"
 	"github.com/google/uuid"
-	"github.com/moby/moby/pkg/namesgenerator"
 	"golang.org/x/xerrors"
 
 	"cdr.dev/slog/v3"
@@ -22,6 +21,7 @@ import (
 	"github.com/coder/coder/v2/coderd/rbac"
 	"github.com/coder/coder/v2/coderd/rbac/policy"
 	"github.com/coder/coder/v2/coderd/telemetry"
+	"github.com/coder/coder/v2/coderd/util/namesgenerator"
 	"github.com/coder/coder/v2/codersdk"
 )
 
@@ -101,7 +101,7 @@ func (api *API) postToken(rw http.ResponseWriter, r *http.Request) {
 		}
 	}
 
-	tokenName := namesgenerator.GetRandomName(1)
+	tokenName := namesgenerator.NameDigitWith("_")
 
 	if len(createToken.TokenName) != 0 {
 		tokenName = createToken.TokenName

coderd/coderdtest/authorize.go

@@ -11,7 +11,6 @@ import (
 	"testing"
 
 	"github.com/google/uuid"
-	"github.com/moby/moby/pkg/namesgenerator"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"golang.org/x/xerrors"
@@ -22,6 +21,7 @@ import (
 	"github.com/coder/coder/v2/coderd/rbac"
 	"github.com/coder/coder/v2/coderd/rbac/policy"
 	"github.com/coder/coder/v2/coderd/rbac/regosql"
+	"github.com/coder/coder/v2/coderd/util/namesgenerator"
 	"github.com/coder/coder/v2/codersdk"
 	"github.com/coder/coder/v2/cryptorand"
 )
@@ -439,10 +439,10 @@ func RandomRBACObject() rbac.Object {
 		OrgID: uuid.NewString(),
 		Type:  randomRBACType(),
 		ACLUserList: map[string][]policy.Action{
-			namesgenerator.GetRandomName(1): {RandomRBACAction()},
+			namesgenerator.UniqueName(): {RandomRBACAction()},
 		},
 		ACLGroupList: map[string][]policy.Action{
-			namesgenerator.GetRandomName(1): {RandomRBACAction()},
+			namesgenerator.UniqueName(): {RandomRBACAction()},
 		},
 	}
 }
@@ -471,7 +471,7 @@ func RandomRBACSubject() rbac.Subject {
 	return rbac.Subject{
 		ID:     uuid.NewString(),
 		Roles:  rbac.RoleIdentifiers{rbac.RoleMember()},
-		Groups: []string{namesgenerator.GetRandomName(1)},
+		Groups: []string{namesgenerator.UniqueName()},
 		Scope:  rbac.ScopeAll,
 	}
 }

coderd/coderdtest/coderdtest.go

@@ -30,17 +30,17 @@ import (
 	"sync/atomic"
 	"testing"
 	"time"
-	"unicode"
 
 	"cloud.google.com/go/compute/metadata"
 	"github.com/fullsailor/pkcs7"
 	"github.com/go-chi/chi/v5"
 	"github.com/golang-jwt/jwt/v4"
 	"github.com/google/uuid"
-	"github.com/moby/moby/pkg/namesgenerator"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	"golang.org/x/text/cases"
+	"golang.org/x/text/language"
 	"golang.org/x/xerrors"
 	"google.golang.org/api/idtoken"
 	"google.golang.org/api/option"
@@ -80,6 +80,7 @@ import (
 	"github.com/coder/coder/v2/coderd/schedule"
 	"github.com/coder/coder/v2/coderd/telemetry"
 	"github.com/coder/coder/v2/coderd/updatecheck"
+	"github.com/coder/coder/v2/coderd/util/namesgenerator"
 	"github.com/coder/coder/v2/coderd/util/ptr"
 	"github.com/coder/coder/v2/coderd/webpush"
 	"github.com/coder/coder/v2/coderd/workspaceapps"
@@ -792,7 +793,7 @@ func AuthzUserSubject(user codersdk.User, orgID uuid.UUID) rbac.Subject {
 
 func createAnotherUserRetry(t testing.TB, client *codersdk.Client, organizationIDs []uuid.UUID, retries int, roles []rbac.RoleIdentifier, mutators ...func(r *codersdk.CreateUserRequestWithOrgs)) (*codersdk.Client, codersdk.User) {
 	req := codersdk.CreateUserRequestWithOrgs{
-		Email:           namesgenerator.GetRandomName(10) + "@coder.com",
+		Email:           namesgenerator.UniqueName() + "@coder.com",
 		Username:        RandomUsername(t),
 		Name:            RandomName(t),
 		Password:        "SomeSecurePassword!",
@@ -1556,37 +1557,15 @@ func NewAzureInstanceIdentity(t testing.TB, instanceID string) (x509.VerifyOptio
 		}
 }
 
-func RandomUsername(t testing.TB) string {
-	suffix, err := cryptorand.String(3)
-	require.NoError(t, err)
-	suffix = "-" + suffix
-	n := strings.ReplaceAll(namesgenerator.GetRandomName(10), "_", "-") + suffix
-	if len(n) > 32 {
-		n = n[:32-len(suffix)] + suffix
-	}
-	return n
+func RandomUsername(_ testing.TB) string {
+	return namesgenerator.UniqueNameWith("-")
 }
 
-func RandomName(t testing.TB) string {
-	var sb strings.Builder
-	var err error
-	ss := strings.Split(namesgenerator.GetRandomName(10), "_")
-	for si, s := range ss {
-		for ri, r := range s {
-			if ri == 0 {
-				_, err = sb.WriteRune(unicode.ToTitle(r))
-				require.NoError(t, err)
-			} else {
-				_, err = sb.WriteRune(r)
-				require.NoError(t, err)
-			}
-		}
-		if si < len(ss)-1 {
-			_, err = sb.WriteRune(' ')
-			require.NoError(t, err)
-		}
-	}
-	return sb.String()
+// RandomName returns a random name in title case (e.g. "Happy Einstein").
+func RandomName(_ testing.TB) string {
+	return cases.Title(language.English).String(
+		namesgenerator.NameWith(" "),
+	)
 }
 
 // Used to easily create an HTTP transport!

coderd/coderdtest/coderdtest_test.go

@@ -1,8 +1,11 @@
 package coderdtest_test
 
 import (
+	"strings"
 	"testing"
+	"unicode"
 
+	"github.com/stretchr/testify/require"
 	"go.uber.org/goleak"
 
 	"github.com/coder/coder/v2/coderd/coderdtest"
@@ -28,3 +31,22 @@ func TestNew(t *testing.T) {
 	_, _ = coderdtest.NewGoogleInstanceIdentity(t, "example", false)
 	_, _ = coderdtest.NewAWSInstanceIdentity(t, "an-instance")
 }
+
+func TestRandomName(t *testing.T) {
+	t.Parallel()
+
+	for range 10 {
+		name := coderdtest.RandomName(t)
+
+		require.NotEmpty(t, name, "name should not be empty")
+		require.NotContains(t, name, "_", "name should not contain underscores")
+
+		// Should be title cased (e.g., "Happy Einstein").
+		words := strings.Split(name, " ")
+		require.Len(t, words, 2, "name should have exactly two words")
+		for _, word := range words {
+			firstRune := []rune(word)[0]
+			require.True(t, unicode.IsUpper(firstRune), "word %q should start with uppercase letter", word)
+		}
+	}
+}

coderd/taskname/taskname.go

@@ -12,11 +12,11 @@ import (
 
 	"github.com/anthropics/anthropic-sdk-go"
 	anthropicoption "github.com/anthropics/anthropic-sdk-go/option"
-	"github.com/moby/moby/pkg/namesgenerator"
 	"golang.org/x/xerrors"
 
 	"cdr.dev/slog/v3"
 	"github.com/coder/aisdk-go"
+	"github.com/coder/coder/v2/coderd/util/namesgenerator"
 	strutil "github.com/coder/coder/v2/coderd/util/strings"
 	"github.com/coder/coder/v2/codersdk"
 )
@@ -125,10 +125,7 @@ func generateFallback() TaskName {
 	// We have a 32 character limit for the name.
 	// We have a 5 character suffix `-ffff`.
 	// This leaves us with 27 characters for the name.
-	//
-	// `namesgenerator.GetRandomName(0)` can generate names
-	// up to 27 characters, but we truncate defensively.
-	name := strings.ReplaceAll(namesgenerator.GetRandomName(0), "_", "-")
+	name := namesgenerator.NameWith("-")
 	name = name[:min(len(name), 27)]
 	name = strings.TrimSuffix(name, "-")
 

coderd/templateversions.go

@@ -16,7 +16,6 @@ import (
 
 	"github.com/go-chi/chi/v5"
 	"github.com/google/uuid"
-	"github.com/moby/moby/pkg/namesgenerator"
 	"github.com/sqlc-dev/pqtype"
 	"github.com/zclconf/go-cty/cty"
 	"golang.org/x/xerrors"
@@ -37,6 +36,7 @@ import (
 	"github.com/coder/coder/v2/coderd/rbac"
 	"github.com/coder/coder/v2/coderd/rbac/policy"
 	"github.com/coder/coder/v2/coderd/tracing"
+	"github.com/coder/coder/v2/coderd/util/namesgenerator"
 	"github.com/coder/coder/v2/coderd/util/ptr"
 	"github.com/coder/coder/v2/codersdk"
 	"github.com/coder/coder/v2/examples"
@@ -1699,7 +1699,7 @@ func (api *API) postTemplateVersionsByOrganization(rw http.ResponseWriter, r *ht
 		}
 
 		if req.Name == "" {
-			req.Name = namesgenerator.GetRandomName(1)
+			req.Name = namesgenerator.NameDigitWith("_")
 		}
 
 		err = tx.InsertTemplateVersion(ctx, database.InsertTemplateVersionParams{

coderd/userauth.go

@@ -19,7 +19,6 @@ import (
 	"github.com/go-jose/go-jose/v4/jwt"
 	"github.com/google/go-github/v43/github"
 	"github.com/google/uuid"
-	"github.com/moby/moby/pkg/namesgenerator"
 	"golang.org/x/oauth2"
 	"golang.org/x/xerrors"
 
@@ -41,6 +40,7 @@ import (
 	"github.com/coder/coder/v2/coderd/render"
 	"github.com/coder/coder/v2/coderd/telemetry"
 	"github.com/coder/coder/v2/coderd/userpassword"
+	"github.com/coder/coder/v2/coderd/util/namesgenerator"
 	"github.com/coder/coder/v2/coderd/util/ptr"
 	"github.com/coder/coder/v2/codersdk"
 	"github.com/coder/coder/v2/cryptorand"
@@ -1723,7 +1723,7 @@ func (api *API) oauthLogin(r *http.Request, params *oauthLoginParams) ([]*http.C
 					validUsername bool
 				)
 				for i := 0; i < 10; i++ {
-					alternate := fmt.Sprintf("%s-%s", original, namesgenerator.GetRandomName(1))
+					alternate := fmt.Sprintf("%s-%s", original, namesgenerator.NameDigitWith("_"))
 
 					params.Username = codersdk.UsernameFrom(alternate)
 

coderd/util/namesgenerator/namesgenerator.go

@@ -0,0 +1,82 @@
+// Package namesgenerator generates random names.
+//
+// This package provides functions for generating random names in the format
+// "adjective_surname" with various options for delimiters and uniqueness.
+//
+// For identifiers that must be unique within a process, use UniqueName or
+// UniqueNameWith. For display purposes where uniqueness is not required,
+// use NameWith.
+package namesgenerator
+
+import (
+	"math/rand/v2"
+	"strconv"
+	"strings"
+	"sync/atomic"
+
+	"github.com/brianvoe/gofakeit/v7"
+)
+
+// maxNameLen is the maximum length for names. Many places in Coder have a 32
+// character limit for names (e.g. usernames, workspace names).
+const maxNameLen = 32
+
+// counter provides unique suffixes for UniqueName functions.
+var counter atomic.Int64
+
+// NameWith returns a random name with a custom delimiter.
+// Names are not guaranteed to be unique.
+func NameWith(delim string) string {
+	const seed = 0 // gofakeit will use a random crypto seed.
+	faker := gofakeit.New(seed)
+	adjective := strings.ToLower(faker.AdjectiveDescriptive())
+	last := strings.ToLower(faker.LastName())
+	return adjective + delim + last
+}
+
+// NameDigitWith returns a random name with a single random digit suffix (1-9),
+// in the format "[adjective][delim][surname][digit]" e.g. "happy_smith9".
+// Provides some collision resistance while keeping names short and clean.
+// Not guaranteed to be unique.
+func NameDigitWith(delim string) string {
+	const (
+		minDigit = 1
+		maxDigit = 9
+	)
+	//nolint:gosec // The random digit doesn't need to be cryptographically secure.
+	return NameWith(delim) + strconv.Itoa(rand.IntN(maxDigit-minDigit+1))
+}
+
+// UniqueName returns a random name with a monotonically increasing suffix,
+// guaranteeing uniqueness within the process. The name is truncated to 32
+// characters if necessary, preserving the numeric suffix.
+func UniqueName() string {
+	return UniqueNameWith("_")
+}
+
+// UniqueNameWith returns a unique name with a custom delimiter.
+// See UniqueName for details on uniqueness guarantees.
+func UniqueNameWith(delim string) string {
+	name := NameWith(delim) + strconv.FormatInt(counter.Add(1), 10)
+	return truncate(name, maxNameLen)
+}
+
+// truncate truncates a name to maxLen characters. It assumes the name ends with
+// a numeric suffix and preserves it, truncating the base name portion instead.
+func truncate(name string, maxLen int) string {
+	if len(name) <= maxLen {
+		return name
+	}
+	// Find where the numeric suffix starts.
+	suffixStart := len(name)
+	for suffixStart > 0 && name[suffixStart-1] >= '0' && name[suffixStart-1] <= '9' {
+		suffixStart--
+	}
+	base := name[:suffixStart]
+	suffix := name[suffixStart:]
+	truncateAt := maxLen - len(suffix)
+	if truncateAt <= 0 {
+		return strconv.Itoa(maxLen) // Fallback, shouldn't happen in practice.
+	}
+	return base[:truncateAt] + suffix
+}

coderd/util/namesgenerator/namesgenerator_internal_test.go

@@ -0,0 +1,103 @@
+package namesgenerator
+
+import (
+	"strings"
+	"testing"
+	"unicode"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestTruncate(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name   string
+		input  string
+		maxLen int
+		want   string
+	}{
+		{
+			name:   "no truncation needed",
+			input:  "foo1",
+			maxLen: 10,
+			want:   "foo1",
+		},
+		{
+			name:   "exact fit",
+			input:  "foo1",
+			maxLen: 4,
+			want:   "foo1",
+		},
+		{
+			name:   "truncate base",
+			input:  "foobar42",
+			maxLen: 5,
+			want:   "foo42",
+		},
+		{
+			name:   "truncate more",
+			input:  "foobar3",
+			maxLen: 3,
+			want:   "fo3",
+		},
+		{
+			name:   "long suffix",
+			input:  "foo123456",
+			maxLen: 8,
+			want:   "fo123456",
+		},
+		{
+			name:   "realistic name",
+			input:  "condescending_proskuriakova999999",
+			maxLen: 32,
+			want:   "condescending_proskuriakov999999",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+			got := truncate(tt.input, tt.maxLen)
+			assert.Equal(t, tt.want, got)
+			assert.LessOrEqual(t, len(got), tt.maxLen)
+		})
+	}
+}
+
+func TestUniqueNameLength(t *testing.T) {
+	t.Parallel()
+
+	// Generate many names to exercise the truncation logic.
+	const iter = 10000
+	for range iter {
+		name := UniqueName()
+		assert.LessOrEqual(t, len(name), maxNameLen)
+		assert.Contains(t, name, "_")
+		assert.Equal(t, name, strings.ToLower(name))
+		verifyNoWhitespace(t, name)
+	}
+}
+
+func TestUniqueNameWithLength(t *testing.T) {
+	t.Parallel()
+
+	// Generate many names with hyphen delimiter.
+	const iter = 10000
+	for range iter {
+		name := UniqueNameWith("-")
+		assert.LessOrEqual(t, len(name), maxNameLen)
+		assert.Contains(t, name, "-")
+		assert.Equal(t, name, strings.ToLower(name))
+		verifyNoWhitespace(t, name)
+	}
+}
+
+func verifyNoWhitespace(t *testing.T, s string) {
+	t.Helper()
+	for _, r := range s {
+		if unicode.IsSpace(r) {
+			t.Fatalf("found whitespace in string %q: %v", s, r)
+		}
+	}
+}