feat: set version equal to module version

As of googleapis/google-cloud-go#5517 we
now have a version file in the internal package for every module.
This change reads variable and uses it for the client version. This
means all autogenerated clients will now get a meaningful realease
version in thier call metadata.

internal/gengapic/doc_file.go

@@ -15,6 +15,7 @@
 package gengapic
 
 import (
+	"fmt"
 	"sort"
 	"strings"
 
@@ -105,6 +106,7 @@ func (g *generator) genDocFile(year int, scopes []string, serv *descriptor.Servi
 	p("//")
 	p("// For information about setting deadlines, reusing contexts, and more")
 	p("// please visit https://pkg.go.dev/cloud.google.com/go.")
+	//TODO(codyoss): use the pkgPath opt
 	p("package %s // import %q", g.opts.pkgName, g.opts.pkgPath)
 	p("")
 
@@ -119,6 +121,7 @@ func (g *generator) genDocFile(year int, scopes []string, serv *descriptor.Servi
 	p("%s%q", "\t", "strings")
 	p("%s%q", "\t", "unicode")
 	p("")
+	p("%s%q", "\t", resolveModuleInternalPkg(g.opts.pkgPath))
 	if hasREST {
 		p("%s%q", "\t", "golang.org/x/xerrors")
 	}
@@ -133,7 +136,7 @@ func (g *generator) genDocFile(year int, scopes []string, serv *descriptor.Servi
 	p("type clientHook func(context.Context, clientHookParams) ([]option.ClientOption, error)")
 	p("")
 
-	p("const versionClient = %q", "UNKNOWN")
+	p("var versionClient = internal.Version")
 	p("")
 
 	p("func insertMetadata(ctx context.Context, mds ...metadata.MD) context.Context {")
@@ -271,3 +274,9 @@ func wrapString(str string, max int) []string {
 
 	return lines
 }
+
+func resolveModuleInternalPkg(pkgPath string) string {
+	pkgSuffix := strings.TrimPrefix(pkgPath, "cloud.google.com/go/")
+	pkg := strings.Split(pkgSuffix, "/")[0]
+	return fmt.Sprintf("cloud.google.com/go/%s/internal", pkg)
+}

internal/gengapic/testdata/doc_file.want

@@ -78,6 +78,7 @@ import (
 	"strings"
 	"unicode"
 
+	"cloud.google.com/go/path/internal"
 	"golang.org/x/xerrors"
 	"google.golang.org/api/option"
 	"google.golang.org/grpc/metadata"
@@ -88,7 +89,7 @@ import (
 type clientHookParams struct{}
 type clientHook func(context.Context, clientHookParams) ([]option.ClientOption, error)
 
-const versionClient = "UNKNOWN"
+var versionClient = internal.Version
 
 func insertMetadata(ctx context.Context, mds ...metadata.MD) context.Context {
 	out, _ := metadata.FromOutgoingContext(ctx)

internal/gengapic/testdata/doc_file_alpha.want

@@ -80,6 +80,7 @@ import (
 	"strings"
 	"unicode"
 
+	"cloud.google.com/go/path/internal"
 	"golang.org/x/xerrors"
 	"google.golang.org/api/option"
 	"google.golang.org/grpc/metadata"
@@ -90,7 +91,7 @@ import (
 type clientHookParams struct{}
 type clientHook func(context.Context, clientHookParams) ([]option.ClientOption, error)
 
-const versionClient = "UNKNOWN"
+var versionClient = internal.Version
 
 func insertMetadata(ctx context.Context, mds ...metadata.MD) context.Context {
 	out, _ := metadata.FromOutgoingContext(ctx)

internal/gengapic/testdata/doc_file_alpha_emptyservice.want

@@ -57,6 +57,7 @@ import (
 	"strings"
 	"unicode"
 
+	"cloud.google.com/go/path/internal"
 	"google.golang.org/api/option"
 	"google.golang.org/grpc/metadata"
 )
@@ -66,7 +67,7 @@ import (
 type clientHookParams struct{}
 type clientHook func(context.Context, clientHookParams) ([]option.ClientOption, error)
 
-const versionClient = "UNKNOWN"
+var versionClient = internal.Version
 
 func insertMetadata(ctx context.Context, mds ...metadata.MD) context.Context {
 	out, _ := metadata.FromOutgoingContext(ctx)

internal/gengapic/testdata/doc_file_beta.want

@@ -80,6 +80,7 @@ import (
 	"strings"
 	"unicode"
 
+	"cloud.google.com/go/path/internal"
 	"golang.org/x/xerrors"
 	"google.golang.org/api/option"
 	"google.golang.org/grpc/metadata"
@@ -90,7 +91,7 @@ import (
 type clientHookParams struct{}
 type clientHook func(context.Context, clientHookParams) ([]option.ClientOption, error)
 
-const versionClient = "UNKNOWN"
+var versionClient = internal.Version
 
 func insertMetadata(ctx context.Context, mds ...metadata.MD) context.Context {
 	out, _ := metadata.FromOutgoingContext(ctx)

internal/gengapic/testdata/doc_file_beta_emptyservice.want

@@ -57,6 +57,7 @@ import (
 	"strings"
 	"unicode"
 
+	"cloud.google.com/go/path/internal"
 	"google.golang.org/api/option"
 	"google.golang.org/grpc/metadata"
 )
@@ -66,7 +67,7 @@ import (
 type clientHookParams struct{}
 type clientHook func(context.Context, clientHookParams) ([]option.ClientOption, error)
 
-const versionClient = "UNKNOWN"
+var versionClient = internal.Version
 
 func insertMetadata(ctx context.Context, mds ...metadata.MD) context.Context {
 	out, _ := metadata.FromOutgoingContext(ctx)

internal/gengapic/testdata/doc_file_emptyservice.want

@@ -55,6 +55,7 @@ import (
 	"strings"
 	"unicode"
 
+	"cloud.google.com/go/path/internal"
 	"google.golang.org/api/option"
 	"google.golang.org/grpc/metadata"
 )
@@ -64,7 +65,7 @@ import (
 type clientHookParams struct{}
 type clientHook func(context.Context, clientHookParams) ([]option.ClientOption, error)
 
-const versionClient = "UNKNOWN"
+var versionClient = internal.Version
 
 func insertMetadata(ctx context.Context, mds ...metadata.MD) context.Context {
 	out, _ := metadata.FromOutgoingContext(ctx)