feat: token introspection (#83)

* introspect

* introspect and client assertion

* introspect and client assertion

* scopes

* token introspection

* introspect

* refactoring

* fixes

* clenaup

* Update example/internal/mock/storage.go

Co-authored-by: Fabi <38692350+fgerschwiler@users.noreply.github.com>

* clenaup

Co-authored-by: Fabi <38692350+fgerschwiler@users.noreply.github.com>

pkg/oidc/introspection.go

@@ -0,0 +1,276 @@
+package oidc
+
+import (
+	"encoding/json"
+	"fmt"
+	"time"
+
+	"golang.org/x/text/language"
+)
+
+type IntrospectionRequest struct {
+	Token string `schema:"token"`
+}
+
+type ClientAssertionParams struct {
+	ClientAssertion     string `schema:"client_assertion"`
+	ClientAssertionType string `schema:"client_assertion_type"`
+}
+
+type IntrospectionResponse interface {
+	UserInfoSetter
+	SetActive(bool)
+	IsActive() bool
+	SetScopes(scopes Scopes)
+	SetClientID(id string)
+}
+
+func NewIntrospectionResponse() IntrospectionResponse {
+	return &introspectionResponse{}
+}
+
+type introspectionResponse struct {
+	Active   bool   `json:"active"`
+	Scope    Scopes `json:"scope,omitempty"`
+	ClientID string `json:"client_id,omitempty"`
+	Subject  string `json:"sub,omitempty"`
+	userInfoProfile
+	userInfoEmail
+	userInfoPhone
+
+	Address UserInfoAddress `json:"address,omitempty"`
+	claims  map[string]interface{}
+}
+
+func (u *introspectionResponse) IsActive() bool {
+	return u.Active
+}
+
+func (u *introspectionResponse) SetScopes(scope Scopes) {
+	u.Scope = scope
+}
+
+func (u *introspectionResponse) SetClientID(id string) {
+	u.ClientID = id
+}
+
+func (u *introspectionResponse) GetSubject() string {
+	return u.Subject
+}
+
+func (u *introspectionResponse) GetName() string {
+	return u.Name
+}
+
+func (u *introspectionResponse) GetGivenName() string {
+	return u.GivenName
+}
+
+func (u *introspectionResponse) GetFamilyName() string {
+	return u.FamilyName
+}
+
+func (u *introspectionResponse) GetMiddleName() string {
+	return u.MiddleName
+}
+
+func (u *introspectionResponse) GetNickname() string {
+	return u.Nickname
+}
+
+func (u *introspectionResponse) GetProfile() string {
+	return u.Profile
+}
+
+func (u *introspectionResponse) GetPicture() string {
+	return u.Picture
+}
+
+func (u *introspectionResponse) GetWebsite() string {
+	return u.Website
+}
+
+func (u *introspectionResponse) GetGender() Gender {
+	return u.Gender
+}
+
+func (u *introspectionResponse) GetBirthdate() string {
+	return u.Birthdate
+}
+
+func (u *introspectionResponse) GetZoneinfo() string {
+	return u.Zoneinfo
+}
+
+func (u *introspectionResponse) GetLocale() language.Tag {
+	return u.Locale
+}
+
+func (u *introspectionResponse) GetPreferredUsername() string {
+	return u.PreferredUsername
+}
+
+func (u *introspectionResponse) GetEmail() string {
+	return u.Email
+}
+
+func (u *introspectionResponse) IsEmailVerified() bool {
+	return u.EmailVerified
+}
+
+func (u *introspectionResponse) GetPhoneNumber() string {
+	return u.PhoneNumber
+}
+
+func (u *introspectionResponse) IsPhoneNumberVerified() bool {
+	return u.PhoneNumberVerified
+}
+
+func (u *introspectionResponse) GetAddress() UserInfoAddress {
+	return u.Address
+}
+
+func (u *introspectionResponse) GetClaim(key string) interface{} {
+	return u.claims[key]
+}
+
+func (u *introspectionResponse) SetActive(active bool) {
+	u.Active = active
+}
+
+func (u *introspectionResponse) SetSubject(sub string) {
+	u.Subject = sub
+}
+
+func (u *introspectionResponse) SetName(name string) {
+	u.Name = name
+}
+
+func (u *introspectionResponse) SetGivenName(name string) {
+	u.GivenName = name
+}
+
+func (u *introspectionResponse) SetFamilyName(name string) {
+	u.FamilyName = name
+}
+
+func (u *introspectionResponse) SetMiddleName(name string) {
+	u.MiddleName = name
+}
+
+func (u *introspectionResponse) SetNickname(name string) {
+	u.Nickname = name
+}
+
+func (u *introspectionResponse) SetUpdatedAt(date time.Time) {
+	u.UpdatedAt = Time(date)
+}
+
+func (u *introspectionResponse) SetProfile(profile string) {
+	u.Profile = profile
+}
+
+func (u *introspectionResponse) SetPicture(picture string) {
+	u.Picture = picture
+}
+
+func (u *introspectionResponse) SetWebsite(website string) {
+	u.Website = website
+}
+
+func (u *introspectionResponse) SetGender(gender Gender) {
+	u.Gender = gender
+}
+
+func (u *introspectionResponse) SetBirthdate(birthdate string) {
+	u.Birthdate = birthdate
+}
+
+func (u *introspectionResponse) SetZoneinfo(zoneInfo string) {
+	u.Zoneinfo = zoneInfo
+}
+
+func (u *introspectionResponse) SetLocale(locale language.Tag) {
+	u.Locale = locale
+}
+
+func (u *introspectionResponse) SetPreferredUsername(name string) {
+	u.PreferredUsername = name
+}
+
+func (u *introspectionResponse) SetEmail(email string, verified bool) {
+	u.Email = email
+	u.EmailVerified = verified
+}
+
+func (u *introspectionResponse) SetPhone(phone string, verified bool) {
+	u.PhoneNumber = phone
+	u.PhoneNumberVerified = verified
+}
+
+func (u *introspectionResponse) SetAddress(address UserInfoAddress) {
+	u.Address = address
+}
+
+func (u *introspectionResponse) AppendClaims(key string, value interface{}) {
+	if u.claims == nil {
+		u.claims = make(map[string]interface{})
+	}
+	u.claims[key] = value
+}
+
+func (i *introspectionResponse) MarshalJSON() ([]byte, error) {
+	type Alias introspectionResponse
+	a := &struct {
+		*Alias
+		Locale    interface{} `json:"locale,omitempty"`
+		UpdatedAt int64       `json:"updated_at,omitempty"`
+		Username  string      `json:"username,omitempty"`
+	}{
+		Alias: (*Alias)(i),
+	}
+	if !i.Locale.IsRoot() {
+		a.Locale = i.Locale
+	}
+	if !time.Time(i.UpdatedAt).IsZero() {
+		a.UpdatedAt = time.Time(i.UpdatedAt).Unix()
+	}
+	a.Username = i.PreferredUsername
+
+	b, err := json.Marshal(a)
+	if err != nil {
+		return nil, err
+	}
+
+	if len(i.claims) == 0 {
+		return b, nil
+	}
+
+	err = json.Unmarshal(b, &i.claims)
+	if err != nil {
+		return nil, fmt.Errorf("jws: invalid map of custom claims %v", i.claims)
+	}
+
+	return json.Marshal(i.claims)
+}
+
+func (i *introspectionResponse) UnmarshalJSON(data []byte) error {
+	type Alias introspectionResponse
+	a := &struct {
+		*Alias
+		UpdatedAt int64 `json:"update_at,omitempty"`
+	}{
+		Alias: (*Alias)(i),
+	}
+	if err := json.Unmarshal(data, &a); err != nil {
+		return err
+	}
+
+	i.UpdatedAt = Time(time.Unix(a.UpdatedAt, 0).UTC())
+
+	if err := json.Unmarshal(data, &i.claims); err != nil {
+		return err
+	}
+
+	return nil
+}