expose field object publicly

rql.go

@@ -17,6 +17,7 @@ import (
 //go:generate easyjson -omit_empty -disallow_unknown_fields -snake_case rql.go
 
 // Query is the decoded result of the user input.
+//
 //easyjson:json
 type Query struct {
 	// Limit must be > 0 and <= to `LimitMaxValue`.
@@ -73,7 +74,6 @@ type Query struct {
 //		return nil, err
 //	}
 //	return users, nil
-//
 type Params struct {
 	// Limit represents the number of rows returned by the SELECT statement.
 	Limit int
@@ -105,7 +105,7 @@ func (p ParseError) Error() string {
 }
 
 // field is a configuration of a struct field.
-type field struct {
+type FieldMeta struct {
 	// Name of the column.
 	Name string
 	// Has a "sort" option in the tag.
@@ -114,6 +114,9 @@ type field struct {
 	Filterable bool
 	// All supported operators for this field.
 	FilterOps map[string]bool
+}
+type Field struct {
+	*FieldMeta
 	// Validation for the type. for example, unit8 greater than or equal to 0.
 	ValidateFn func(interface{}) error
 	// ConvertFn converts the given value to the type value.
@@ -124,7 +127,7 @@ type field struct {
 // It is safe for concurrent use by multiple goroutines except for configuration changes.
 type Parser struct {
 	Config
-	fields map[string]*field
+	fields map[string]*Field
 }
 
 // NewParser creates a new Parser. it fails if the configuration is invalid.
@@ -134,14 +137,31 @@ func NewParser(c Config) (*Parser, error) {
 	}
 	p := &Parser{
 		Config: c,
-		fields: make(map[string]*field),
+		fields: make(map[string]*Field),
 	}
 	if err := p.init(); err != nil {
 		return nil, err
 	}
 	return p, nil
 }
 
+// Does not use config.Model, gets config from Fields)
+func NewParserF(c Config, fields []*Field) (*Parser, error) {
+	if err := c.defaults(); err != nil {
+		return nil, err
+	}
+
+	m := make(map[string]*Field, len(fields))
+	for _, v := range fields {
+		m[v.Name] = v
+	}
+	p := &Parser{
+		Config: c,
+		fields: m,
+	}
+	return p, nil
+}
+
 // MustNewParser is like NewParser but panics if the configuration is invalid.
 // It simplifies safe initialization of global variables holding a resource parser.
 func MustNewParser(c Config) *Parser {
@@ -197,13 +217,20 @@ func (p *Parser) ParseQuery(q *Query) (pr *Params, err error) {
 	return
 }
 
+func (p *Parser) GetFields() []*Field {
+	fields := make([]*Field, 0, len(p.fields))
+	for _, v := range p.fields {
+		fields = append(fields, v)
+	}
+	return fields
+}
+
 // Column is the default function that converts field name into a database column.
 // It used to convert the struct fields into their database names. For example:
 //
 //	Username => username
 //	FullName => full_name
 //	HTTPCode => http_code
-//
 func Column(s string) string {
 	var b strings.Builder
 	for i := 0; i < len(s); i++ {
@@ -257,10 +284,12 @@ func (p *Parser) init() error {
 // parseField parses the given struct field tag, and add a rule
 // in the parser according to its type and the options that were set on the tag.
 func (p *Parser) parseField(sf reflect.StructField) error {
-	f := &field{
-		Name:      p.ColumnFn(sf.Name),
-		CovertFn:  valueFn,
-		FilterOps: make(map[string]bool),
+	f := &Field{
+		FieldMeta: &FieldMeta{
+			Name:      p.ColumnFn(sf.Name),
+			FilterOps: make(map[string]bool),
+		},
+		CovertFn: valueFn,
 	}
 	layout := time.RFC3339
 	opts := strings.Split(sf.Tag.Get(p.TagName), ",")
@@ -438,7 +467,7 @@ func (p *parseState) relOp(op Op, terms []interface{}) {
 	}
 }
 
-func (p *parseState) field(f *field, v interface{}) {
+func (p *parseState) field(f *Field, v interface{}) {
 	terms, ok := v.(map[string]interface{})
 	// default equality check.
 	if !ok {

rql_test.go

@@ -1021,3 +1021,58 @@ func mustParseTime(layout, s string) time.Time {
 	t, _ := time.Parse(layout, s)
 	return t
 }
+
+func TestGetFields(t *testing.T) {
+	tests := []struct {
+		name    string
+		conf    Config
+		wantOut []*Field
+	}{
+		{
+			name: "get fields",
+			conf: Config{
+				Model: struct {
+					SomeName string `rql:"filter"`
+				}{},
+			},
+			wantOut: []*Field{
+				&Field{
+					FieldMeta: &FieldMeta{
+						Name:       "some_name",
+						Sortable:   false,
+						Filterable: true,
+					},
+					// Column:     "some_name",
+					// AvailableOps: []string{"$eq", "$neq", "$lt", "$lte", "$gt", "$gte", "$like"},
+				},
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			p, err := NewParser(tt.conf)
+			if err != nil {
+				t.Fatalf("failed to build parser: %v", err)
+			}
+			out := p.GetFields()
+			assertFieldsEqual(t, out, tt.wantOut)
+		})
+	}
+}
+
+func assertFieldsEqual(t *testing.T, got []*Field, want []*Field) {
+	if len(got) != len(want) {
+		t.Fatalf("got %v, wanted %v", got, want)
+	}
+	for i := 0; i < len(got); i++ {
+		if got[i].Filterable != want[i].Filterable {
+			t.Fatalf("Filterable got:%v want: %v", got[i].Filterable, want[i].Filterable)
+		}
+		if got[i].Sortable != want[i].Sortable {
+			t.Fatalf("Sortable got:%v want: %v", got[i].Sortable, want[i].Sortable)
+		}
+		if got[i].Name != want[i].Name {
+			t.Fatalf("Name got:%v want: %v", got[i].Name, want[i].Name)
+		}
+	}
+}