Merge pull request #221 from vektah/middleware-stack

Implement FieldMiddleware Stack
99designs · Jul 26, 2018 · 803711e · 803711e
2 parents 66593ff + 0ec918b
commit 803711e
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Showing 29 changed files with 733 additions and 1,787 deletions.
diff --git a/codegen/build.go b/codegen/build.go
@@ -21,6 +21,7 @@ type Build struct {
 	SubscriptionRoot *Object
 	SchemaRaw        string
 	SchemaFilename   string
+	Directives       []*Directive
 }
 
 type ModelBuild struct {
@@ -84,6 +85,7 @@ func (cfg *Config) bind() (*Build, error) {
 		Imports:        imports.finalize(),
 		SchemaRaw:      cfg.SchemaStr,
 		SchemaFilename: cfg.SchemaFilename,
+		Directives:     cfg.buildDirectives(),
 	}
 
 	if cfg.schema.Query != nil {

diff --git a/codegen/directive.go b/codegen/directive.go
@@ -0,0 +1,5 @@
+package codegen
+
+type Directive struct {
+	Name string
+}
diff --git a/codegen/directive_build.go b/codegen/directive_build.go
@@ -0,0 +1,13 @@
+package codegen
+
+func (cfg *Config) buildDirectives() (directives []*Directive) {
+	for name := range cfg.schema.Directives {
+		if name == "skip" || name == "include" || name == "deprecated" {
+			continue
+		}
+		directives = append(directives, &Directive{
+			Name: name,
+		})
+	}
+	return directives
+}
diff --git a/codegen/templates/data.go b/codegen/templates/data.go
diff --git a/codegen/templates/field.gotpl b/codegen/templates/field.gotpl
@@ -46,7 +46,7 @@
 			rctx.PushField(field.Alias)
 			defer rctx.Pop()
 		{{- end }}
-			resTmp, err := ec.ResolverMiddleware(ctx, func(ctx context.Context) (interface{}, error) {
+			resTmp := ec.FieldMiddleware(ctx, func(ctx context.Context) (interface{}, error) {
 				{{- if $field.IsResolver }}
 					return ec.resolvers.{{ $field.ShortInvocation }}
 				{{- else if $field.GoVarName }}
@@ -59,10 +59,6 @@
 					{{- end }}
 				{{- end }}
 			})
-			if err != nil {
-				ec.Error(ctx, err)
-				return graphql.Null
-			}
 			if resTmp == nil {
 				return graphql.Null
 			}

diff --git a/codegen/templates/generated.gotpl b/codegen/templates/generated.gotpl
@@ -9,8 +9,16 @@ import (
 )
 
 // NewExecutableSchema creates an ExecutableSchema from the ResolverRoot interface.
-func NewExecutableSchema(resolvers ResolverRoot) graphql.ExecutableSchema {
-	return &executableSchema{resolvers: resolvers}
+func NewExecutableSchema(cfg Config) graphql.ExecutableSchema {
+	return &executableSchema{
+		resolvers: cfg.Resolvers,
+		directives: cfg.Directives,
+	}
+}
+
+type Config struct {
+	Resolvers  ResolverRoot
+	Directives DirectiveRoot
 }
 
 type ResolverRoot interface {
@@ -21,6 +29,12 @@ type ResolverRoot interface {
 {{- end }}
 }
 
+type DirectiveRoot struct {
+{{ range $directive := .Directives }}
+	{{$directive.Name|ucFirst}} graphql.FieldMiddleware
+{{ end }}
+}
+
 {{- range $object := .Objects -}}
 	{{ if $object.HasResolvers }}
 		type {{$object.GQLType}}Resolver interface {
@@ -32,7 +46,8 @@ type ResolverRoot interface {
 {{- end }}
 
 type executableSchema struct {
-	resolvers      ResolverRoot
+	resolvers  ResolverRoot
+	directives DirectiveRoot
 }
 
 func (e *executableSchema) Schema() *ast.Schema {
@@ -41,7 +56,7 @@ func (e *executableSchema) Schema() *ast.Schema {
 
 func (e *executableSchema) Query(ctx context.Context, op *ast.OperationDefinition) *graphql.Response {
 	{{- if .QueryRoot }}
-		ec := executionContext{graphql.GetRequestContext(ctx), e.resolvers}
+		ec := executionContext{graphql.GetRequestContext(ctx), e}
 
 		buf := ec.RequestMiddleware(ctx, func(ctx context.Context) []byte {
 			data := ec._{{.QueryRoot.GQLType}}(ctx, op.SelectionSet)
@@ -61,7 +76,7 @@ func (e *executableSchema) Query(ctx context.Context, op *ast.OperationDefinitio
 
 func (e *executableSchema) Mutation(ctx context.Context, op *ast.OperationDefinition) *graphql.Response {
 	{{- if .MutationRoot }}
-		ec := executionContext{graphql.GetRequestContext(ctx), e.resolvers}
+		ec := executionContext{graphql.GetRequestContext(ctx), e}
 
 		buf := ec.RequestMiddleware(ctx, func(ctx context.Context) []byte {
 			data := ec._{{.MutationRoot.GQLType}}(ctx, op.SelectionSet)
@@ -81,7 +96,7 @@ func (e *executableSchema) Mutation(ctx context.Context, op *ast.OperationDefini
 
 func (e *executableSchema) Subscription(ctx context.Context, op *ast.OperationDefinition) func() *graphql.Response {
 	{{- if .SubscriptionRoot }}
-		ec := executionContext{graphql.GetRequestContext(ctx), e.resolvers}
+		ec := executionContext{graphql.GetRequestContext(ctx), e}
 
 		next := ec._{{.SubscriptionRoot.GQLType}}(ctx, op.SelectionSet)
 		if ec.Errors != nil {
@@ -113,8 +128,7 @@ func (e *executableSchema) Subscription(ctx context.Context, op *ast.OperationDe
 
 type executionContext struct {
 	*graphql.RequestContext
-
-	resolvers ResolverRoot
+	*executableSchema
 }
 
 {{- range $object := .Objects }}
@@ -133,6 +147,31 @@ type executionContext struct {
 	{{ template "input.gotpl" $input }}
 {{- end }}
 
+func (ec *executionContext) FieldMiddleware(ctx context.Context, next graphql.Resolver) interface{} {
+	{{- if .Directives }}
+	rctx := graphql.GetResolverContext(ctx)
+	for _, d := range rctx.Field.Definition.Directives {
+		switch d.Name {
+		{{- range $directive := .Directives }}
+		case "{{$directive.Name}}":
+			if ec.directives.{{$directive.Name|ucFirst}} != nil {
+				n := next
+				next = func(ctx context.Context) (interface{}, error) {
+					return ec.directives.{{$directive.Name|ucFirst}}(ctx, n)
+				}
+			}
+		{{- end }}
+		}
+	}
+	{{- end }}
+	res, err := ec.ResolverMiddleware(ctx, next)
+	if err != nil {
+		ec.Error(ctx, err)
+		return nil
+	}
+	return res
+}
+
 func (ec *executionContext) introspectSchema() *introspection.Schema {
 	return introspection.WrapSchema(parsedSchema)
 }