// marshalEndpoint marshals a service endpoint into a json schema
func marshalEndpoint(ep *Endpoint) (*jsonschema.JsonSchema, error) {
reqT, resT := ep.ProtoTypes()
if reqT == nil && resT == nil {
return nil, nil
}
// Generate the root schema for this endpoint
rootSchema := jsonschema.New()
rootSchema.Id = fmt.Sprintf("http://directory.hailoweb.com/service/%s-%v.json#%s", Name, Version, ep.GetName())
rootSchema.Title = fmt.Sprintf("%s-%v.%s", Name, Version, ep.GetName())
rootSchema.Description = fmt.Sprintf("%s endpoint schema for %s-%v", ep.GetName(), Name, Version)
rootSchema.Type = jsonschema.TYPE_OBJECT
rootSchema.Schema = "http://json-schema.org/draft-04/schema#"
if reqT != nil {
// Generate the request skeleton
reqSchema := jsonschema.New()
reqSchema.Property = "Request"
reqSchema.Parent = rootSchema
if err := reflectEndpoint(reqT, reqSchema); err != nil {
return nil, err
}
if len(reqSchema.Properties) > 0 || len(reqSchema.Definitions) > 0 {
reqSchema.Type = jsonschema.TYPE_OBJECT
}
rootSchema.AddProperty(reqSchema)
}
if resT != nil {
// Generate the response skeleton
resSchema := jsonschema.New()
resSchema.Property = "Response"
resSchema.Parent = rootSchema
if err := reflectEndpoint(resT, resSchema); err != nil {
return nil, err
}
if len(resSchema.Properties) > 0 || len(resSchema.Definitions) > 0 {
resSchema.Type = jsonschema.TYPE_OBJECT
}
rootSchema.AddProperty(resSchema)
}
// All definitions go on the root level
definitions := make(map[string]*jsonschema.JsonSchema, 20)
for _, child := range rootSchema.DefinitionsChildren {
definitions[child.Property] = child
}
rootSchema.Definitions = definitions
return rootSchema, nil
}
// reflectEndpoint traverses a given endpoint and returns a predefined json schema
// based on its data
func reflectEndpoint(typ reflect.Type, schema *jsonschema.JsonSchema) error {
if typ.Kind() == reflect.Ptr {
typ = typ.Elem()
}
// Iterate over not built-in types
if typ.PkgPath() != "" && typ.Kind() == reflect.Struct {
for i := 0; i < typ.NumField(); i++ {
f := typ.Field(i)
tag := f.Tag.Get("protobuf")
// If there are no proto tags, we assume the field is unused
if tag == "" {
continue
}
// Parse the proto tags
priority, propertyName, _, enum := parseProtoTag(tag)
// Create a property wrapper
prop := jsonschema.New()
prop.Property = propertyName
prop.Parent = schema
var (
items *jsonschema.JsonSchema
isSlice bool
)
typ := f.Type
// Check if we have a slice
if typ.Kind() == reflect.Slice {
typ = typ.Elem()
isSlice = true
items = jsonschema.New()
items.Parent = prop
}
// Check if we have a ptr and get the underlying type
if typ.Kind() == reflect.Ptr {
typ = typ.Elem()
}
// Add this to the required fields on this level if necessary
if priority == "req" {
if err := schema.AddRequired(propertyName); err != nil {
return err
}
}
// Deal with enums
if enum != "" {
enumVals := getProtoEnumValues(typ)
if isSlice {
items.Type = jsonschema.TYPE_STRING
items.Enum = enumVals
prop.Items = items
prop.Type = jsonschema.TYPE_ARRAY
} else {
prop.Type = jsonschema.TYPE_STRING
prop.Enum = enumVals
}
if err := schema.AddProperty(prop); err != nil {
return err
}
continue
}
// Deal with custom types
if typ.PkgPath() != "" {
// If this was a slice, create a new property and add the ref as a child
// Otherwise, add the reference as a normal property
if isSlice {
items.Ref = fmt.Sprintf("#/definitions/%s", typ.String())
prop.Items = items
prop.Type = jsonschema.TYPE_ARRAY
if err := schema.AddProperty(prop); err != nil {
return err
}
} else {
ref := jsonschema.New()
ref.Ref = fmt.Sprintf("#/definitions/%s", typ.String())
ref.Parent = schema
ref.Property = propertyName
if err := schema.AddProperty(ref); err != nil {
return err
}
}
// Create a new definition for this object and iterate it
// NOTE: We always put definitions at root level
root := findRoot(schema)
if root == nil {
root = schema
}
def := jsonschema.New()
def.Property = typ.String()
def.Parent = root
def.Type = jsonschema.TYPE_OBJECT
root.AddDefinitionChild(def)
reflectEndpoint(typ, def)
continue
}
// We are dealing with a builtin type
switch typ.Kind() {
case reflect.String:
prop.Type = jsonschema.TYPE_STRING
case reflect.Bool:
prop.Type = jsonschema.TYPE_BOOLEAN
case reflect.Int, reflect.Int16, reflect.Int8, reflect.Int32, reflect.Int64,
reflect.Uint, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uint8:
prop.Type = jsonschema.TYPE_INTEGER
case reflect.Float32, reflect.Float64, reflect.Complex128, reflect.Complex64:
prop.Type = jsonschema.TYPE_NUMBER
default:
// We should never get here
log.Errorf("Unhandled type: %v", typ.Kind())
continue
}
// If we had a slice on this iteration, use the prop type for the nested items scheme
if isSlice {
items.Type = prop.Type
prop.Type = jsonschema.TYPE_ARRAY
prop.Items = items
}
if err := schema.AddProperty(prop); err != nil {
return err
}
}
}
return nil
}
