Add plugin for providing config via schema directives

api/generate.go

@@ -8,6 +8,7 @@ import (
 	"github.com/99designs/gqlgen/plugin"
 	"github.com/99designs/gqlgen/plugin/modelgen"
 	"github.com/99designs/gqlgen/plugin/resolvergen"
+	"github.com/99designs/gqlgen/plugin/schemaconfig"
 	"github.com/pkg/errors"
 	"golang.org/x/tools/go/packages"
 )
@@ -17,6 +18,7 @@ func Generate(cfg *config.Config, option ...Option) error {
 	_ = syscall.Unlink(cfg.Model.Filename)
 
 	plugins := []plugin.Plugin{
+		schemaconfig.New(),
 		modelgen.New(),
 		resolvergen.New(),
 	}

example/config/.gqlgen.yml

@@ -15,16 +15,9 @@ resolver:
 models:
   Todo:    # Object
     fields:
-      id:
-        resolver: true
       text:
         fieldName: Description # Field
   NewTodo: # Input
     fields:
       userId:
         fieldName: UserID      # Field
-  User:
-    model: github.com/99designs/gqlgen/example/config.User
-    fields:
-      name:
-        fieldName: FullName    # Method

example/config/schema.graphql

@@ -1,3 +1,6 @@
+directive @goModel(model: String, models: [String!]) on OBJECT | INPUT_OBJECT | SCALAR | ENUM | INTERFACE | UNION
+directive @goField(forceResolver: Boolean, name: String) on INPUT_FIELD_DEFINITION | FIELD_DEFINITION
+
 type Query {
   todos: [Todo!]!
 }

example/config/todo.graphql

@@ -1,5 +1,5 @@
 type Todo {
-  id: ID!
+  id: ID! @goField(forceResolver: true)
   databaseId: Int!
   text: String!
   done: Boolean!

example/config/user.graphql

@@ -1,4 +1,5 @@
-type User {
+type User
+@goModel(model:"github.com/99designs/gqlgen/example/config.User") {
   id: ID!
-  name: String!
+  name: String! @goField(name:"FullName")
 }

plugin/schemaconfig/schemaconfig.go

@@ -0,0 +1,95 @@
+package schemaconfig
+
+import (
+	"github.com/99designs/gqlgen/codegen/config"
+	"github.com/99designs/gqlgen/plugin"
+	"github.com/vektah/gqlparser/ast"
+)
+
+func New() plugin.Plugin {
+	return &Plugin{}
+}
+
+type Plugin struct{}
+
+var _ plugin.ConfigMutator = &Plugin{}
+
+func (m *Plugin) Name() string {
+	return "schemaconfig"
+}
+
+func (m *Plugin) MutateConfig(cfg *config.Config) error {
+	if err := cfg.Check(); err != nil {
+		return err
+	}
+
+	schema, _, err := cfg.LoadSchema()
+	if err != nil {
+		return err
+	}
+
+	cfg.InjectBuiltins(schema)
+
+	cfg.Directives["goModel"] = config.DirectiveConfig{
+		SkipRuntime: true,
+	}
+
+	cfg.Directives["goField"] = config.DirectiveConfig{
+		SkipRuntime: true,
+	}
+
+	for _, schemaType := range schema.Types {
+		if schemaType == schema.Query || schemaType == schema.Mutation || schemaType == schema.Subscription {
+			continue
+		}
+
+		if bd := schemaType.Directives.ForName("goModel"); bd != nil {
+			if ma := bd.Arguments.ForName("model"); ma != nil {
+				if mv, err := ma.Value.Value(nil); err == nil {
+					cfg.Models.Add(schemaType.Name, mv.(string))
+				}
+			}
+			if ma := bd.Arguments.ForName("models"); ma != nil {
+				if mvs, err := ma.Value.Value(nil); err == nil {
+					for _, mv := range mvs.([]interface{}) {
+						cfg.Models.Add(schemaType.Name, mv.(string))
+					}
+				}
+			}
+		}
+
+		if schemaType.Kind == ast.Object || schemaType.Kind == ast.InputObject {
+			for _, field := range schemaType.Fields {
+				if fd := field.Directives.ForName("goField"); fd != nil {
+					forceResolver := cfg.Models[schemaType.Name].Fields[field.Name].Resolver
+					fieldName := cfg.Models[schemaType.Name].Fields[field.Name].FieldName
+
+					if ra := fd.Arguments.ForName("forceResolver"); ra != nil {
+						if fr, err := ra.Value.Value(nil); err == nil {
+							forceResolver = fr.(bool)
+						}
+					}
+
+					if na := fd.Arguments.ForName("name"); na != nil {
+						if fr, err := na.Value.Value(nil); err == nil {
+							fieldName = fr.(string)
+						}
+					}
+
+					if cfg.Models[schemaType.Name].Fields == nil {
+						cfg.Models[schemaType.Name] = config.TypeMapEntry{
+							Model:  cfg.Models[schemaType.Name].Model,
+							Fields: map[string]config.TypeMapField{},
+						}
+					}
+
+					cfg.Models[schemaType.Name].Fields[field.Name] = config.TypeMapField{
+						FieldName: fieldName,
+						Resolver:  forceResolver,
+					}
+				}
+			}
+		}
+	}
+	return nil
+}