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type.go
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type.go
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// Copyright 2019-present Facebook Inc. All rights reserved.
// This source code is licensed under the Apache 2.0 license found
// in the LICENSE file in the root directory of this source tree.
package gen
import (
"fmt"
"go/token"
"path"
"reflect"
"sort"
"strconv"
"strings"
"unicode"
"github.com/facebookincubator/ent"
"github.com/facebookincubator/ent/dialect/sql/schema"
"github.com/facebookincubator/ent/entc/load"
"github.com/facebookincubator/ent/schema/field"
)
type (
// Type represents one node-type in the graph, its relations and
// the information it holds.
Type struct {
*Config
// schema definition.
schema *load.Schema
// Name holds the type/ent name.
Name string
// ID holds the ID field of this type.
ID *Field
// Fields holds all the primitive fields of this type.
Fields []*Field
fields map[string]*Field
// Edge holds all the edges of this type.
Edges []*Edge
// Indexes are the configured indexes for this type.
Indexes []*Index
// ForeignKeys are the foreign-keys that resides in the type table.
ForeignKeys []*ForeignKey
foreignKeys map[string]struct{}
}
// Field holds the information of a type field used for the templates.
Field struct {
// field definition.
def *load.Field
// Name is the name of this field in the database schema.
Name string
// Type holds the type information of the field.
Type *field.TypeInfo
// Unique indicate if this field is a unique field.
Unique bool
// Optional indicates is this field is optional on create.
Optional bool
// Nillable indicates that this field can be null in the
// database and pointer in the generated entities.
Nillable bool
// Default indicates if this field has a default value for creation.
Default bool
// UpdateDefault indicates if this field has a default value for update.
UpdateDefault bool
// Immutable indicates is this field cannot be updated.
Immutable bool
// StructTag of the field. default to "json".
StructTag string
// Validators holds the number of validators this field have.
Validators int
// Position info of the field.
Position *load.Position
// UserDefined indicates that this field was defined by the loaded schema.
// Unlike default id field, which is defined by the generator.
UserDefined bool
}
// Edge of a graph between two types.
Edge struct {
// Name holds the name of the edge.
Name string
// Type holds a reference to the type this edge is directed to.
Type *Type
// Optional indicates is this edge is optional on create.
Optional bool
// Unique indicates if this edge is a unique edge.
Unique bool
// Inverse holds the name of the reference edge declared in the schema.
Inverse string
// Owner holds the type of the edge-owner. For assoc-edges it's the
// type that holds the edge, for inverse-edges, it's the assoc type.
Owner *Type
// StructTag of the edge-field in the struct. default to "json".
StructTag string
// Relation holds the relation info of an edge.
Rel Relation
// Bidi indicates if this edge is a bidirectional edge. A self-reference
// to the same type with the same name (symmetric relation). For example,
// a User type have one of following edges:
//
// edge.To("friends", User.Type) // many 2 many.
// edge.To("spouse", User.Type).Unique() // one 2 one.
//
Bidi bool
}
// Relation holds the relational database information for edges.
Relation struct {
// Type holds the relation type of the edge.
Type Rel
// Table holds the relation table for this edge.
// For O2O and O2M, it's the table name of the type we're this edge point to.
// For M2O, this is the owner's type, and for M2M this is the join table.
Table string
// Columns holds the relation column in the relation table above.
// In O2M, M2O and O2O, this the first element.
Columns []string
}
// Index represents a database index used for either increasing speed
// on database operations or defining constraints such as "UNIQUE INDEX".
// Note that some indexes are created implicitly like table foreign keys.
Index struct {
// Name of the index. One column index is simply the column name.
Name string
// Unique index or not.
Unique bool
// Columns are the table columns.
Columns []string
}
// ForeignKey holds the information for foreign-key columns of types.
// It's exported only because it's used by the codegen templates and
// should not be used beside that.
ForeignKey struct {
// Field information for the foreign-key column.
Field *Field
// Edge that is associated with this foreign-key.
Edge *Edge
}
)
// NewType creates a new type and its fields from the given schema.
func NewType(c *Config, schema *load.Schema) (*Type, error) {
typ := &Type{
Config: c,
ID: &Field{
Name: "id",
Type: c.IDType,
StructTag: `json:"id,omitempty"`,
},
schema: schema,
Name: schema.Name,
Fields: make([]*Field, 0, len(schema.Fields)),
fields: make(map[string]*Field, len(schema.Fields)),
foreignKeys: make(map[string]struct{}),
}
for _, f := range schema.Fields {
switch {
case f.Name == "":
return nil, fmt.Errorf("field name cannot be empty")
case f.Info == nil || !f.Info.Valid():
return nil, fmt.Errorf("invalid type for field %s", f.Name)
case f.Nillable && !f.Optional:
return nil, fmt.Errorf("nillable field %q must be optional", f.Name)
case f.Unique && f.Default:
return nil, fmt.Errorf("unique field %q cannot have default value", f.Name)
case typ.fields[f.Name] != nil:
return nil, fmt.Errorf("field %q redeclared for type %q", f.Name, typ.Name)
case f.Sensitive && f.Tag != "":
return nil, fmt.Errorf("sensitive field %q cannot have struct tags", f.Name)
case f.Info.Type == field.TypeEnum:
if err := validEnums(f); err != nil {
return nil, err
}
// Enum types should be named as follows: typepkg.Field.
f.Info.Ident = fmt.Sprintf("%s.%s", typ.Package(), pascal(f.Name))
}
tf := &Field{
def: f,
Name: f.Name,
Type: f.Info,
Unique: f.Unique,
Position: f.Position,
Nillable: f.Nillable,
Optional: f.Optional,
Default: f.Default,
UpdateDefault: f.UpdateDefault,
Immutable: f.Immutable,
StructTag: structTag(f.Name, f.Tag),
Validators: f.Validators,
UserDefined: true,
}
// user defined id field.
if tf.Name == typ.ID.Name {
typ.ID = tf
} else {
typ.Fields = append(typ.Fields, tf)
typ.fields[f.Name] = tf
}
}
return typ, nil
}
// Label returns Gremlin label name of the node/type.
func (t Type) Label() string { return snake(t.Name) }
// Table returns SQL table name of the node/type.
func (t Type) Table() string {
if t.schema != nil && t.schema.Config.Table != "" {
return t.schema.Config.Table
}
return snake(rules.Pluralize(t.Name))
}
// Package returns the package name of this node.
func (t Type) Package() string { return strings.ToLower(t.Name) }
// Receiver returns the receiver name of this node. It makes sure the
// receiver names doesn't conflict with import names.
func (t Type) Receiver() string {
return receiver(t.Name)
}
// HasAssoc returns true if this type has an assoc edge with the given name.
// faster than map access for most cases.
func (t Type) HasAssoc(name string) (*Edge, bool) {
for _, e := range t.Edges {
if name == e.Name {
return e, true
}
}
return nil, false
}
// HasValidators reports if any of the type's field has validators.
func (t Type) HasValidators() bool {
for _, f := range t.Fields {
if f.Validators > 0 {
return true
}
}
return false
}
// HasDefault reports if any of this type's fields has default value on creation.
func (t Type) HasDefault() bool {
for _, f := range t.Fields {
if f.Default {
return true
}
}
return false
}
// HasUpdateDefault reports if any of this type's fields has default value on update.
func (t Type) HasUpdateDefault() bool {
for _, f := range t.Fields {
if f.UpdateDefault {
return true
}
}
return false
}
// HasOptional reports if this type has an optional field.
func (t Type) HasOptional() bool {
for _, f := range t.Fields {
if f.Optional {
return true
}
}
return false
}
// HasNumeric reports if this type has a numeric field.
func (t Type) HasNumeric() bool {
for _, f := range t.Fields {
if f.Type.Numeric() {
return true
}
}
return false
}
// FKEdges returns all edges that reside on the type table as foreign-keys.
func (t Type) FKEdges() (edges []*Edge) {
for _, e := range t.Edges {
if e.OwnFK() {
edges = append(edges, e)
}
}
return
}
// MixedInWithDefaultOrValidator returns all mixed-in fields with default values for creation or update.
func (t Type) MixedInWithDefaultOrValidator() (fields []*Field) {
for _, f := range t.Fields {
if f.Position != nil && f.Position.MixedIn && (f.Default || f.UpdateDefault || f.Validators > 0) {
fields = append(fields, f)
}
}
return
}
// NumMixin returns the type's mixin count.
func (t Type) NumMixin() int {
m := make(map[int]struct{})
for _, f := range t.Fields {
if p := f.Position; p != nil && p.MixedIn {
m[p.MixinIndex] = struct{}{}
}
}
return len(m)
}
// NumConstraint returns the type's constraint count. Used for slice allocation.
func (t Type) NumConstraint() int {
var n int
for _, f := range t.Fields {
if f.Unique {
n++
}
}
for _, e := range t.Edges {
if e.HasConstraint() {
n++
}
}
return n
}
// MutableFields returns the types's mutable fields.
func (t Type) MutableFields() []*Field {
var fields []*Field
for _, f := range t.Fields {
if !f.Immutable {
fields = append(fields, f)
}
}
return fields
}
// NumM2M returns the type's many-to-many edge count
func (t Type) NumM2M() int {
var n int
for _, e := range t.Edges {
if e.M2M() {
n++
}
}
return n
}
// TagTypes returns all struct-tag types of the type fields.
func (t Type) TagTypes() []string {
tags := make(map[string]bool)
for _, f := range t.Fields {
tag := reflect.StructTag(f.StructTag)
fields := strings.FieldsFunc(f.StructTag, func(r rune) bool {
return r == ':' || unicode.IsSpace(r)
})
for _, name := range fields {
_, ok := tag.Lookup(name)
if ok && !tags[name] {
tags[name] = true
}
}
}
r := make([]string, 0, len(tags))
for tag := range tags {
r = append(r, tag)
}
sort.Strings(r)
return r
}
// AddIndex adds a new index for the type.
// It fails if the schema index is invalid.
func (t *Type) AddIndex(idx *load.Index) error {
index := &Index{Name: idx.StorageKey, Unique: idx.Unique}
if len(idx.Fields) == 0 && len(idx.Edges) == 0 {
return fmt.Errorf("missing fields or edges")
}
for _, name := range idx.Fields {
f, ok := t.fields[name]
if !ok {
return fmt.Errorf("unknown index field %q", name)
}
if f.def.Size != nil && *f.def.Size > schema.DefaultStringLen {
return fmt.Errorf("field %q exceeds the index size limit (%d)", name, schema.DefaultStringLen)
}
index.Columns = append(index.Columns, f.StorageKey())
}
for _, name := range idx.Edges {
var edge *Edge
for _, e := range t.Edges {
if e.Name == name {
edge = e
break
}
}
switch {
case edge == nil:
return fmt.Errorf("unknown index field %q", name)
case edge.Rel.Type == O2O && !edge.IsInverse():
return fmt.Errorf("non-inverse edge (edge.From) for index %q on O2O relation", name)
case edge.Rel.Type != M2O && edge.Rel.Type != O2O:
return fmt.Errorf("relation %s for inverse edge %q is not one of (O2O, M2O)", edge.Rel.Type, name)
default:
index.Columns = append(index.Columns, edge.Rel.Column())
}
}
// If no storage-key was defined for this index, generate one.
if idx.StorageKey == "" {
// Add the type name as a prefix to the index parts, because
// multiple types can share the same index attributes.
parts := append([]string{strings.ToLower(t.Name)}, index.Columns...)
index.Name = strings.Join(parts, "_")
}
t.Indexes = append(t.Indexes, index)
return nil
}
// resolveFKs makes sure all edge-fks are created for the types.
func (t *Type) resolveFKs() {
for _, e := range t.Edges {
if e.IsInverse() || e.M2M() {
continue
}
refid := t.ID
if e.OwnFK() {
refid = e.Type.ID
}
fk := &ForeignKey{
Edge: e,
Field: &Field{
Name: e.Rel.Column(),
Type: refid.Type,
Nillable: true,
Optional: true,
Unique: e.Unique,
UserDefined: refid.UserDefined,
},
}
if e.OwnFK() {
t.addFK(fk)
} else {
e.Type.addFK(fk)
}
}
}
// AddForeignKey adds a foreign-key for the type if it doesn't exist.
func (t *Type) addFK(fk *ForeignKey) {
if _, ok := t.foreignKeys[fk.Field.Name]; ok {
return
}
t.foreignKeys[fk.Field.Name] = struct{}{}
t.ForeignKeys = append(t.ForeignKeys, fk)
}
// QueryName returns the struct name of the query builder for this type.
func (t Type) QueryName() string {
return pascal(t.Name) + "Query"
}
// MutationName returns the struct name of the mutation builder for this type.
func (t Type) MutationName() string {
return pascal(t.Name) + "Mutation"
}
// SiblingImports returns all sibling packages that are needed for the different builders.
func (t Type) SiblingImports() []string {
var (
paths = []string{path.Join(t.Config.Package, t.Package())}
seen = map[string]bool{paths[0]: true}
)
for _, e := range t.Edges {
name := path.Join(t.Config.Package, e.Type.Package())
if !seen[name] {
seen[name] = true
paths = append(paths, name)
}
}
return paths
}
// NumHooks returns the number of hooks declared in the type schema.
func (t Type) NumHooks() int {
if t.schema != nil {
return t.schema.Hooks
}
return 0
}
// HasPolicy returns whether a privacy policy was declared in the type schema.
func (t Type) HasPolicy() bool {
if t.schema != nil {
return t.schema.Policy
}
return false
}
// Constant returns the constant name of the field.
func (f Field) Constant() string {
return "Field" + pascal(f.Name)
}
// DefaultName returns the variable name of the default value of this field.
func (f Field) DefaultName() string { return "Default" + pascal(f.Name) }
// UpdateDefaultName returns the variable name of the update default value of this field.
func (f Field) UpdateDefaultName() string { return "Update" + f.DefaultName() }
// DefaultValue returns the default value of the field. Invoked by the template.
func (f Field) DefaultValue() interface{} { return f.def.DefaultValue }
// BuilderField returns the struct member of the field in the builder.
func (f Field) BuilderField() string {
return builderField(f.Name)
}
// StructField returns the struct member of the field in the model.
func (f Field) StructField() string {
return pascal(f.Name)
}
// Enums returns the enum values of a field.
func (f Field) Enums() []string {
if f.IsEnum() {
return f.def.Enums
}
return nil
}
// EnumName returns the constant name of the enum value.
func (f Field) EnumName(enum string) string {
return pascal(f.Name) + pascal(enum)
}
// Validator returns the validator name.
func (f Field) Validator() string { return pascal(f.Name) + "Validator" }
// mutMethods returns the method names of mutation interface.
var mutMethods = func() map[string]struct{} {
t := reflect.TypeOf(new(ent.Mutation)).Elem()
names := make(map[string]struct{})
for i := 0; i < t.NumMethod(); i++ {
names[t.Method(i).Name] = struct{}{}
}
return names
}()
// MutationGet returns the method name for getting the field value.
// The default name is just a pascal format. If the the method conflicts
// with the mutation methods, prefix the method with "Get".
func (f Field) MutationGet() string {
name := pascal(f.Name)
if _, ok := mutMethods[name]; ok {
name = "Get" + name
}
return name
}
// IsTime returns true if the field is a timestamp field.
func (f Field) IsTime() bool { return f.Type != nil && f.Type.Type == field.TypeTime }
// IsJSON returns true if the field is a JSON field.
func (f Field) IsJSON() bool { return f.Type != nil && f.Type.Type == field.TypeJSON }
// IsString returns true if the field is a string field.
func (f Field) IsString() bool { return f.Type != nil && f.Type.Type == field.TypeString }
// IsUUID returns true if the field is a UUID field.
func (f Field) IsUUID() bool { return f.Type != nil && f.Type.Type == field.TypeUUID }
// IsInt returns true if the field is an int field.
func (f Field) IsInt() bool { return f.Type != nil && f.Type.Type == field.TypeInt }
// IsEnum returns true if the field is an enum field.
func (f Field) IsEnum() bool { return f.Type != nil && f.Type.Type == field.TypeEnum }
// Sensitive returns true if the field is a sensitive field.
func (f Field) Sensitive() bool { return f.def != nil && f.def.Sensitive }
// NullType returns the sql null-type for optional and nullable fields.
func (f Field) NullType() string {
switch f.Type.Type {
case field.TypeJSON:
return "[]byte"
case field.TypeString, field.TypeEnum:
return "sql.NullString"
case field.TypeBool:
return "sql.NullBool"
case field.TypeTime:
return "sql.NullTime"
case field.TypeInt, field.TypeInt8, field.TypeInt16, field.TypeInt32, field.TypeInt64,
field.TypeUint, field.TypeUint8, field.TypeUint16, field.TypeUint32, field.TypeUint64:
return "sql.NullInt64"
case field.TypeFloat32, field.TypeFloat64:
return "sql.NullFloat64"
}
return f.Type.String()
}
// NullTypeField extracts the nullable type field (if exists) from the given receiver.
// It also does the type conversion if needed.
func (f Field) NullTypeField(rec string) string {
switch f.Type.Type {
case field.TypeEnum:
return fmt.Sprintf("%s(%s.String)", f.Type, rec)
case field.TypeString, field.TypeBool, field.TypeInt64, field.TypeFloat64:
return fmt.Sprintf("%s.%s", rec, strings.Title(f.Type.String()))
case field.TypeTime:
return fmt.Sprintf("%s.Time", rec)
case field.TypeFloat32:
return fmt.Sprintf("%s(%s.Float64)", f.Type, rec)
case field.TypeInt, field.TypeInt8, field.TypeInt16, field.TypeInt32,
field.TypeUint, field.TypeUint8, field.TypeUint16, field.TypeUint32, field.TypeUint64:
return fmt.Sprintf("%s(%s.Int64)", f.Type, rec)
}
return rec
}
// Column returns the table column. It sets it as a primary key (auto_increment) in case of ID field.
func (f Field) Column() *schema.Column {
f.Enums()
c := &schema.Column{
Name: f.StorageKey(),
Type: f.Type.Type,
Unique: f.Unique,
Nullable: f.Optional,
Enums: f.Enums(),
Size: f.size(),
}
switch {
case f.Default && (f.Type.Numeric() || f.Type.Type == field.TypeBool):
c.Default = f.DefaultValue()
case f.Default && (f.IsString() || f.IsEnum()):
if s, ok := f.DefaultValue().(string); ok {
c.Default = strconv.Quote(s)
}
}
return c
}
// size returns the the field size defined in the schema.
func (f Field) size() int64 {
if f.def != nil && f.def.Size != nil {
return *f.def.Size
}
return 0
}
// PK is like Column, but for table primary key.
func (f Field) PK() *schema.Column {
c := &schema.Column{
Name: f.StorageKey(),
Type: field.TypeInt,
Key: schema.PrimaryKey,
Increment: true,
}
// If the PK was defined by the user and it's UUID or string.
if f.UserDefined && !f.Type.Numeric() {
c.Increment = false
c.Type = f.Type.Type
c.Unique = f.Unique
if f.def != nil && f.def.Size != nil {
c.Size = *f.def.Size
}
}
return c
}
// StorageKey returns the storage name of the field.
// SQL columns or Gremlin property.
func (f Field) StorageKey() string {
if f.def != nil && f.def.StorageKey != "" {
return f.def.StorageKey
}
return snake(f.Name)
}
// Label returns the Gremlin label name of the edge.
// If the edge is inverse
func (e Edge) Label() string {
if e.IsInverse() {
return fmt.Sprintf("%s_%s", e.Owner.Label(), snake(e.Inverse))
}
return fmt.Sprintf("%s_%s", e.Owner.Label(), snake(e.Name))
}
// Constant returns the constant name of the edge.
func (e Edge) Constant() string {
return "Edge" + pascal(e.Name)
}
// M2M indicates if this edge is M2M edge.
func (e Edge) M2M() bool { return e.Rel.Type == M2M }
// M2O indicates if this edge is M2O edge.
func (e Edge) M2O() bool { return e.Rel.Type == M2O }
// O2M indicates if this edge is O2M edge.
func (e Edge) O2M() bool { return e.Rel.Type == O2M }
// O2O indicates if this edge is O2O edge.
func (e Edge) O2O() bool { return e.Rel.Type == O2O }
// IsInverse returns if this edge is an inverse edge.
func (e Edge) IsInverse() bool { return e.Inverse != "" }
// Constant returns the constant name of the edge for the gremlin dialect.
// If the edge is inverse, it returns the constant name of the owner-edge (assoc-edge).
func (e Edge) LabelConstant() string {
name := e.Name
if e.IsInverse() {
name = e.Inverse
}
return pascal(name) + "Label"
}
// InverseConstant returns the inverse constant name of the edge.
func (e Edge) InverseLabelConstant() string { return pascal(e.Name) + "InverseLabel" }
// TableConstant returns the constant name of the relation table.
func (e Edge) TableConstant() string { return pascal(e.Name) + "Table" }
// InverseTableConstant returns the constant name of the other/inverse type of the relation.
func (e Edge) InverseTableConstant() string { return pascal(e.Name) + "InverseTable" }
// ColumnConstant returns the constant name of the relation column.
func (e Edge) ColumnConstant() string { return pascal(e.Name) + "Column" }
// PKConstant returns the constant name of the primary key. Used for M2M edges.
func (e Edge) PKConstant() string { return pascal(e.Name) + "PrimaryKey" }
// HasConstraint indicates if this edge has a unique constraint check.
// We check uniqueness when both-directions are unique or one of them.
// Used by the Gremlin storage-layer.
func (e Edge) HasConstraint() bool {
return e.Rel.Type == O2O || e.Rel.Type == O2M
}
// BuilderField returns the struct member of the edge in the builder.
func (e Edge) BuilderField() string {
return builderField(e.Name)
}
// StructField returns the struct member of the edge in the model.
func (e Edge) StructField() string {
return pascal(e.Name)
}
// StructFKField returns the struct member for holding the edge
// foreign-key in the model.
func (e Edge) StructFKField() string {
return e.Rel.Column()
}
// OwnFK indicates if the foreign-key of this edge is owned by the edge
// column (reside in the type's table). Used by the SQL storage-driver.
func (e Edge) OwnFK() bool {
switch {
case e.M2O():
return true
case e.O2O() && (e.IsInverse() || e.Bidi):
return true
}
return false
}
// Column returns the first element from the columns slice.
func (r Relation) Column() string {
if len(r.Columns) == 0 {
panic(fmt.Sprintf("missing column for Relation.Table: %s", r.Table))
}
return r.Columns[0]
}
// Rel is a relation type of an edge.
type Rel int
// Relation types.
const (
Unk Rel = iota // Unknown.
O2O // One to one / has one.
O2M // One to many / has many.
M2O // Many to one (inverse perspective for O2M).
M2M // Many to many.
)
// String returns the relation name.
func (r Rel) String() string {
s := "Unknown"
switch r {
case O2O:
s = "O2O"
case O2M:
s = "O2M"
case M2O:
s = "M2O"
case M2M:
s = "M2M"
}
return s
}
func structTag(name, tag string) string {
t := fmt.Sprintf(`json:"%s,omitempty"`, name)
if tag == "" {
return t
}
if _, ok := reflect.StructTag(tag).Lookup("json"); !ok {
tag = t + " " + tag
}
return tag
}
func validEnums(f *load.Field) error {
if len(f.Enums) == 0 {
return fmt.Errorf("missing values for enum field %q", f.Name)
}
values := make(map[string]bool, len(f.Enums))
for _, e := range f.Enums {
switch {
case e == "":
return fmt.Errorf("%q field value cannot be empty", f.Name)
case values[e]:
return fmt.Errorf("duplicate values %q for enum field %q", e, f.Name)
default:
values[e] = true
}
}
if value := f.DefaultValue; value != nil {
if value, ok := value.(string); !ok || !values[value] {
return fmt.Errorf("invalid default value for enum field %q", f.Name)
}
}
return nil
}
// builderField returns the struct field for the given name
// and ensures it doesn't conflict with Go keywords and other
// builder fields and it's not exported.
func builderField(name string) string {
if token.Lookup(name).IsKeyword() || name == "config" || strings.ToUpper(name[:1]) == name[:1] {
return "_" + name
}
return name
}