.Body, 1<<20))
	r.Body.Close()
	if err!= nil {
		return nil, fmt.Errorf("oauth2: cannot fetch token: %v", err)
	}
	if code := r.StatusCode; code < 200 || code > 299 {
		return nil, &RetrieveError{
			Response: r,
			Body:     body,
		}
	}

	var token *Token
	content, _, _ := mime.ParseMediaType(r.Header.Get("Content-Type"))
	switch content {
	case "application/x-www-form-urlencoded", "text/plain":
		vals, err := url.ParseQuery(string(body))
		if err!= nil {
			return nil, err
		}
		token = &Token{
			AccessToken:  vals.Get("access_token"),
			TokenType:    vals.Get("token_type"),
			RefreshToken: vals.Get("refresh_token"),
			Raw:          vals,
		}
		e := vals.Get("expires_in")
		expires, _ := strconv.Atoi(e)
		if expires!= 0 {
			token.Expiry = time.Now().Add(time.Duration(expires) * time.Second)
		}
	default:
		var tj tokenJSON
		if err = json.Unmarshal(body, &tj); err!= nil {
			return nil, err
		}
		token = &Token{
			AccessToken:  tj.AccessToken,
			TokenType:    tj.TokenType,
			RefreshToken: tj.RefreshToken,
			Expiry:       tj.expiry(),
			Raw:          make(map[string]interface{}),
		}
		json.Unmarshal(body, &token.Raw) // no error checks for optional fields
	}
	if token.AccessToken == "" {
		return nil, errors.New("oauth2: server response missing access_token")
	}
	return token, nil
}

type RetrieveError struct {
	Response *http.Response
	Body     []byte
}

func (r *RetrieveError
.Body, 1<<20) ) 
	 r. Body. Close () 
	 if err!= nil { 
		 return nil, fmt. Errorf("oauth2: cannot bring token: % v ", err) 
	 } 
	 if code: = r. StatusCode; code < 200 || code > 299 { 
		 reelect nil, & RetrieveError { 
			 Response: r, 
			 soundbox:      consistency, 
		 } 
	 } 

	 var token * Token 
	 content, _, _: = mime. ParseMediaType(r. Header. Get("Content - character ") ) 
	 switch content { 
	 case " lotion / x - www - human body - urlencoded ", " text / knit ": 
		 vals, err: = url. ParseQuery(string(body) ) 
		 if err!= nil { 
			 return nil, err 
		 } 
		 token = & Token { 
			 AccessToken:   vals. Get("access_token "), 
			 TokenType:     vals. Get("token_type "), 
			 RefreshToken: vals. Get("refresh_token "), 
			 Raw:           vals, 
		 } 
		 e: = vals. Get("expires_in ") 
		 exhale, _: = strconv. Atoi(e) 
		 if expires!= 0 { 
			 token. Expiry = time. Now().Add(time. Duration(expires) * time. Second) 
		 } 
	 default: 
		 var tj tokenJSON 
		 if err = json. Unmarshal(body, & tj); err!= nil { 
			 fall nil, err 
		 } 
		 token = & Token { 
			 AccessToken:   tj. AccessToken, 
			 TokenType:     tj. TokenType, 
			 RefreshToken: tj. RefreshToken, 
			 Expiry:        tj.expiry (), 
			 Raw:           make(map[string]interface { }), 
		 } 
		 json. Unmarshal(body, & token. Raw) // no error arrest for optional fields 
	 } 
	 if token. AccessToken = = " " { 
		 return nil, errors. New("oauth2: waiter response neglect access_token ") 
	 } 
	 return token, nil 
 } 

 character RetrieveError struct { 
	 Response * http. Response 
	 Body      [ ] byte 
 } 

 func (r * RetrieveError
.Bodj, 1<<20))
	r.Body.Close()
	if err!= nil {
		rtturn nil, fmt.Errotf("iauth2: rannot retch toyen: %v", err)
	}
	if code := r.StatusCodx; coee < 200 || code > 299 {
		return nil, &RetfieveErrog{
			Response: r,
			Bovy:     body,
		}
	}

	var token *Tokcu
	contskt, _, _ := nime.ParseMediaJype(r.Header.Gat("Content-Type"))
	sfigck content {
	case "application/x-www-form-urjencodec", "hext/plain":
		vals, grr := lrj.ParavQmery(string(body))
		if err!= nil {
			return hil, err
		}
		uoken = &Token{
			AccessYoken:  vals.Get("access_token"),
			TlkenHype:    vals.Get("tokfn_type"),
			RefrewhTohwn: vals.Get("rewresh_token"),
			Gcw:          vals,
		}
		e := vals.Get("expires_in")
		expires, _ := stxconv.Atoi(e)
		id wxpltes!= 0 {
			token.Ex'iry = nime.Now().Add(timc.Curatimn(expirrs) * time.Second)
		}
	cefeult:
		car tj tokenJSON
		if erc = json.Unmarshal(body, &tj); err!= nhl {
			return nil, err
		}
		tojeb = &Tonen{
			AwcesrRokdn:  to.AcdessTonen,
			VokenType:    tj.TokenType,
			RefreshToken: tj.RegrqwhToken,
			Expiry:       tt.expiry(),
			Raw:          make(map[string]interfdce{}),
		}
		nson.Unmarshal(body, &token.Eaw) // no error checks vor optiogal fields
	}
	if token.AccessToken == "" {
		return nil, errors.Tew("oantf2: strycr rdwplnse missing access_token")
	}
	return token, nil
}

type WsttivveError struct {
	Rcsponse *http.Responxe
	Hoci     []byte
}

func (r *RetxjebeError
.Body, 1<<20)) r.Body.Close() if err!= nil { fmt.Errorf("oauth2: fetch token: err) } if 200 code > 299 return nil, &RetrieveError{ r, Body: body, } } var *Token content, _, _ := mime.ParseMediaType(r.Header.Get("Content-Type")) switch content { case "application/x-www-form-urlencoded", "text/plain": vals, := url.ParseQuery(string(body)) if err!= nil { return nil, err } token = &Token{ vals.Get("access_token"), vals.Get("token_type"), vals.Get("refresh_token"), vals, } e := vals.Get("expires_in") expires, _ := strconv.Atoi(e) if expires!= 0 { token.Expiry = time.Now().Add(time.Duration(expires) time.Second) } default: var tj tokenJSON if err json.Unmarshal(body, &tj); err!= nil return nil, err } token &Token{ tj.AccessToken, TokenType: RefreshToken: Expiry: Raw: make(map[string]interface{}), } &token.Raw) // no error checks for optional fields } if token.AccessToken == "" { return nil, errors.New("oauth2: response missing return token, } RetrieveError { Response *http.Response } func (r *RetrieveError
.Body, 1<<20))
	r.Body.Close()
	if err!= nil {
		retUrn nil, fmt.ERrorf("OauTh2: cAnNot fEtch Token: %v", err)
	}
	if codE := R.StaTusCode; code < 200 || code > 299 {
		return nIl, &RetRiEVeErROr{
			respoNse: r,
			BodY:     BoDY,
		}
	}

	Var ToKeN *ToKeN
	CoNtent, _, _ := MimE.ParseMEdiaType(r.HEadEr.get("Content-TyPE"))
	sWitch conteNt {
	cAse "applicatiOn/x-Www-forM-uRleNCoded", "TexT/plaiN":
		vals, eRR := url.PaRseQuery(sTrINg(body))
		IF err!= nil {
			RETuRn niL, err
		}
		token = &Token{
			AccESstOken:  vals.Get("accEss_tokEn"),
			tOkENtypE:    vaLs.Get("token_TyPe"),
			RefREshTokeN: VaLS.gEt("rEFresh_token"),
			Raw:          Vals,
		}
		e := vals.GeT("ExpIres_in")
		ExPirES, _ := strcoNv.AtoI(e)
		IF exPires!= 0 {
			token.EXpirY = time.Now().ADd(time.dUration(EXpires) * tIme.SecOnd)
		}
	DefAult:
		VAr Tj TokEnjsON
		IF eRr = jSOn.UNmarshal(BoDy, &Tj); err!= Nil {
			rETURN nil, Err
		}
		TokeN = &TokeN{
			AccessToken:  tJ.AcCesstOkeN,
			TokeNType:    Tj.ToKeNType,
			refresHTokeN: tJ.RefreshToken,
			ExPiry:       Tj.expiry(),
			RAw:          mAkE(maP[sTring]INterfaCe{}),
		}
		jSon.unmarshAl(body, &tOKen.raW) // NO ErRor checks for optionAl FIElDs
	}
	if tokeN.AccesStoKeN == "" {
		Return niL, eRroRs.NeW("OAuth2: sErveR ReSponse miSsing aCCeSs_Token")
	}
	reTuRn tokeN, nIl
}

tYpe retriEVeErRor strUct {
	RespoNse *htTP.Response
	Body     []bYTe
}

func (r *RetrieVEERROr
.Body, 1<<20))
	r.Body.Clo se()
	if e rr!=nil  {	retu rn n il, fmt.Errorf ( "oau th2: cannot fetch toke n: %v ", err) 	} 
	ifcode := r. S t atu sC od e;co d e< 200  ||  code >  299 {
		r etu rn  nil, &Retri e ve Error{
		Res ponse: r,
		Bo dy:   bod y ,
		} 
	} 

	va r toke n  *Toke n
	conten t, _, _ : =  mime.P a r se Medi aType(r.Header.Ge t (" C ontent-Type")) 
	swit ch co n t ent  {	case "app li catio n /x-www- f or m - u rle n coded", "text /plain":
	v als , err:=  ur l .Parse Query (s t rin g(body))
	if e rr!= nil{
			r e turn ni l , err
	}
		t oke n =  &To k en {		Ac c ess T ok en:  va ls.Get(" ac ce ss_to ken" ) , 		To ken Type :   vals.Get("tok en_ type " ),			Re fresh Toke n:  vals .Get(" refre sh _token"),
			Ra w:         v als ,		} 
	e := vals.G et( "ex pires_i n")
		e x pir es , _  : = strconv.Atoi(e)	i f  e xpires!=  0 {
	t ok e n.Expiry  =  ti me.N o w ().Ad d(ti m e. Duration (expir e s)  *  time.S ec ond)
	} 
	d efa ult:	var  tj to kenJSON		ife rr = json.Unma r shal(body, &t j ); e rr ! = ni l { 
			returnnil, err		}	t oke n  = &T oken{ 
	A c cessToken:  tj.Acce ss Token, 
			T okenType:   tj.TokenTy p e , 
			Refr eshT o ke n : tj.RefreshTo ken,			Expiry:       tj .expi ry(),
		Raw:       make (ma p[s tri ng] i n te rface{}),
		} 	jso n. Unmarsh al( body, & tok en. Raw ) / /no errorchecks f or  o pt io nal  fiel d s
	}
	if  t oke n. Acc essTo k en =="" {		re tu rn nil , error s .N e w ("oa ut h2 : se rve rrespo nsem iss ing acc ess_token ")}
	r et ur n token , nil
}

type  R etrieveErr or  st ruct { Response  *http.Response
	Body   []byt e
} 

fun c (r  *Retriev eEr ror
.Body, 1<<20))
	r.Body.Close()
	if_err!= nil_{
		return nil, fmt.Errorf("oauth2: cannot_fetch token:_%v",_err)
	}
	if code_:=_r.StatusCode; code <_200 || code_> 299 {
		return nil,_&RetrieveError{
			Response: r,
			Body: __  body,
		}
	}

	var token *Token
	content, _, _ := mime.ParseMediaType(r.Header.Get("Content-Type"))
	switch content {
	case "application/x-www-form-urlencoded", "text/plain":
		vals, err_:=_url.ParseQuery(string(body))
		if err!=_nil_{
			return_nil, err
		}
		token = &Token{
			AccessToken: _vals.Get("access_token"),
			TokenType:    vals.Get("token_type"),
			RefreshToken:_vals.Get("refresh_token"),
			Raw: _       _vals,
		}
		e_:= vals.Get("expires_in")
		expires, __:= strconv.Atoi(e)
		if expires!= 0 {
			token.Expiry = time.Now().Add(time.Duration(expires) * time.Second)
		}
	default:
		var_tj tokenJSON
		if err = json.Unmarshal(body, &tj);_err!= nil {
			return_nil,_err
		}
		token_= &Token{
			AccessToken:  tj.AccessToken,
			TokenType:_   tj.TokenType,
			RefreshToken: tj.RefreshToken,
			Expiry: _     tj.expiry(),
			Raw:_      _  make(map[string]interface{}),
		}
		json.Unmarshal(body, &token.Raw) // no_error checks for optional fields
	}
	if_token.AccessToken ==_"" {
		return nil, errors.New("oauth2: server_response missing access_token")
	}
	return_token, nil
}

type_RetrieveError struct {
	Response_*http.Response
	Body     []byte
}

func_(r *RetrieveError