feat: add config level host

Author: Josh Newman

README.md

@@ -35,8 +35,9 @@ go install github.com/technicallyjosh/protoc-gen-openapi@latest
 | `content_type`     | The content type to be associated with all operations.<sup>1</sup>                | application/json |
 | `json_names`       | Use the JSON names that Protobuf provides. Otherwise, proto field names are used. | false            |
 | `json_out`         | Create a JSON file instead of the default YAML.                                   | false            |
+| `host`             | The host to be used for all operations.<sup>1</sup>                               |                  |
 
-<sup>1</sup> _Can be overridden on a service or method._
+<sup>1</sup> _Can be overridden on a file, service, or method._
 
 ## Using Buf
 

internal/generator/generator.go

@@ -13,14 +13,15 @@ import (
 
 // Config holds the configuration for the generator.
 type Config struct {
-	Version         *string
-	Title           *string
+	ContentType     *string
+	DefaultResponse *string
 	Description     *string
+	Host            *string
 	Ignore          *string
-	DefaultResponse *string
-	ContentType     *string
-	UseJSONNames    *bool
 	JSONOutput      *bool
+	Title           *string
+	UseJSONNames    *bool
+	Version         *string
 }
 
 // Generator is an instance that parses the given folder and its Protobuf files into OAPI.

internal/generator/path.go

@@ -36,9 +36,13 @@ func newServer(host string) (*openapi3.Server, error) {
 func (g *Generator) addPathsToDoc(doc *openapi3.T, services []*protogen.Service) error {
 	contentType := *g.config.ContentType
 
+	// Default to config defined host.
+	host := *g.config.Host
+
 	for _, service := range services {
-		var host, pathPrefix string
+		var pathPrefix string
 
+		// Apply/Override file options.
 		extFile := proto.GetExtension(service.Desc.ParentFile().Options(), oapiv1.E_File)
 		if extFile != nil && extFile != oapiv1.E_File.InterfaceOf(oapiv1.E_File.Zero()) {
 			fileOptions := extFile.(*oapiv1.FileOptions)
@@ -51,6 +55,7 @@ func (g *Generator) addPathsToDoc(doc *openapi3.T, services []*protogen.Service)
 
 		serviceOptions := new(oapiv1.ServiceOptions)
 
+		// Service options.
 		extService := proto.GetExtension(service.Desc.Options(), oapiv1.E_Service)
 		if extService != nil && extService != oapiv1.E_Service.InterfaceOf(oapiv1.E_Service.Zero()) {
 			serviceOptions = extService.(*oapiv1.ServiceOptions)
@@ -91,6 +96,7 @@ func (g *Generator) addPathsToDoc(doc *openapi3.T, services []*protogen.Service)
 
 			var methodOptions *oapiv1.MethodOptions
 
+			// Method options. If not present, continue to next.
 			extMethod := proto.GetExtension(method.Desc.Options(), oapiv1.E_Method)
 			if extMethod != nil && extMethod != oapiv1.E_Method.InterfaceOf(oapiv1.E_Method.Zero()) {
 				methodOptions = extMethod.(*oapiv1.MethodOptions)

main.go

@@ -11,14 +11,15 @@ func main() {
 	var flags flag.FlagSet
 
 	conf := generator.Config{
-		Version:         flags.String("version", "0.0.1", "Version of the API."),
-		Title:           flags.String("title", "", "Title of the API"),
+		ContentType:     flags.String("content_type", "application/json", "Default content-type for all paths."),
+		DefaultResponse: flags.String("default_response", "", "Default response message to use for API responses not defined."),
 		Description:     flags.String("description", "", "Description of the API."),
+		Host:            flags.String("host", "", "Host to be used for all routes."),
 		Ignore:          flags.String("ignore", "", "Packages to ignore."),
-		DefaultResponse: flags.String("default_response", "", "Default response message to use for API responses not defined."),
-		ContentType:     flags.String("content_type", "application/json", "Default content-type for all paths."),
-		UseJSONNames:    flags.Bool("json_names", false, "Use JSON names instead of the proto names of fields."),
 		JSONOutput:      flags.Bool("json_out", false, "Generate a JSON file instead of YAML."),
+		Title:           flags.String("title", "", "Title of the API"),
+		UseJSONNames:    flags.Bool("json_names", false, "Use JSON names instead of the proto names of fields."),
+		Version:         flags.String("version", "0.0.1", "Version of the API."),
 	}
 
 	opts := protogen.Options{