Implement types.yaml parsing

Gopkg.toml

@@ -15,3 +15,7 @@ required = ["github.com/vektah/dataloaden"]
 [prune]
   go-tests = true
   unused-packages = true
+
+[[constraint]]
+  name = "gopkg.in/yaml.v2"
+  version = "2.2.1"

codegen/codegen.go

@@ -51,13 +51,13 @@ func (tm TypeMap) Get(typeName string) *TypeMapEntry {
 }
 
 type TypeMapEntry struct {
-	TypeName   string
-	EntityPath string
+	TypeName   string `yaml:"typeName"`
+	EntityPath string `yaml:"entityPath"`
 	Fields     []TypeMapField
 }
 
 type TypeMapField struct {
-	FieldName string
+	FieldName string `yaml:"fieldName"`
 }
 
 func Generate(cfg Config) error {

main.go

@@ -6,8 +6,10 @@ import (
 	"fmt"
 	"io/ioutil"
 	"os"
+	"strings"
 
 	"github.com/vektah/gqlgen/codegen"
+	"gopkg.in/yaml.v2"
 )
 
 var output = flag.String("out", "generated.go", "the file to write to")
@@ -58,6 +60,19 @@ func loadTypeMap() codegen.TypeMap {
 	if *typemap == "" {
 		return nil
 	}
+
+	if strings.HasSuffix(*typemap, ".json") {
+		return loadTypeMapJSON()
+	}
+
+	return loadTypeMapYAML()
+}
+
+func loadTypeMapJSON() codegen.TypeMap {
+	if *typemap == "" {
+		return nil
+	}
+
 	b, err := ioutil.ReadFile(*typemap)
 	if err != nil {
 		fmt.Fprintln(os.Stderr, "unable to open typemap: "+err.Error())
@@ -89,3 +104,23 @@ func loadTypeMap() codegen.TypeMap {
 
 	return typeMap
 }
+
+func loadTypeMapYAML() codegen.TypeMap {
+	if *typemap == "" {
+		return nil
+	}
+
+	b, err := ioutil.ReadFile(*typemap)
+	if err != nil {
+		fmt.Fprintln(os.Stderr, "unable to open typemap: "+err.Error())
+		return nil
+	}
+
+	var typeMap codegen.TypeMap
+	if err = yaml.Unmarshal(b, &typeMap); err != nil {
+		fmt.Fprintln(os.Stderr, "unable to parse typemap: "+err.Error())
+		os.Exit(1)
+	}
+
+	return typeMap
+}

test/resolvers_test.go

@@ -1,4 +1,4 @@
-//go:generate gorunpkg github.com/vektah/gqlgen -out generated.go -typemap types.json -models models/generated.go
+//go:generate gorunpkg github.com/vektah/gqlgen -out generated.go -typemap types.yaml -models models/generated.go
 
 package test
 

test/types.yaml

@@ -0,0 +1,8 @@
+- typeName:   Element
+  entityPath: github.com/vektah/gqlgen/test.Element
+
+- typeName:   Viewer
+  entityPath: github.com/vektah/gqlgen/test.Viewer
+
+- typeName:   User
+  entityPath: remote_api.User