chore: vendor go dependencies

13 files changed, 1507 insertions, 0 deletions

diff --git a/vendor/golang.org/x/oauth2/.travis.yml b/vendor/golang.org/x/oauth2/.travis.yml
new file mode 100644
index 0000000..fa139db
--- /dev/null
+++ b/vendor/golang.org/x/oauth2/.travis.yml
@@ -0,0 +1,13 @@
+language: go
+
+go:
+  - tip
+
+install:
+  - export GOPATH="$HOME/gopath"
+  - mkdir -p "$GOPATH/src/golang.org/x"
+  - mv "$TRAVIS_BUILD_DIR" "$GOPATH/src/golang.org/x/oauth2"
+  - go get -v -t -d golang.org/x/oauth2/...
+
+script:
+  - go test -v golang.org/x/oauth2/...
diff --git a/vendor/golang.org/x/oauth2/CONTRIBUTING.md b/vendor/golang.org/x/oauth2/CONTRIBUTING.md
new file mode 100644
index 0000000..dfbed62
--- /dev/null
+++ b/vendor/golang.org/x/oauth2/CONTRIBUTING.md
@@ -0,0 +1,26 @@
+# Contributing to Go
+
+Go is an open source project.
+
+It is the work of hundreds of contributors. We appreciate your help!
+
+## Filing issues
+
+When [filing an issue](https://github.com/golang/oauth2/issues), make sure to answer these five questions:
+
+1.  What version of Go are you using (`go version`)?
+2.  What operating system and processor architecture are you using?
+3.  What did you do?
+4.  What did you expect to see?
+5.  What did you see instead?
+
+General questions should go to the [golang-nuts mailing list](https://groups.google.com/group/golang-nuts) instead of the issue tracker.
+The gophers there will answer or ask you to file an issue if you've tripped over a bug.
+
+## Contributing code
+
+Please read the [Contribution Guidelines](https://golang.org/doc/contribute.html)
+before sending patches.
+
+Unless otherwise noted, the Go source files are distributed under
+the BSD-style license found in the LICENSE file.
diff --git a/vendor/golang.org/x/oauth2/LICENSE b/vendor/golang.org/x/oauth2/LICENSE
new file mode 100644
index 0000000..2a7cf70
--- /dev/null
+++ b/vendor/golang.org/x/oauth2/LICENSE
@@ -0,0 +1,27 @@
+Copyright 2009 The Go Authors.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google LLC nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/vendor/golang.org/x/oauth2/README.md b/vendor/golang.org/x/oauth2/README.md
new file mode 100644
index 0000000..48dbb9d
--- /dev/null
+++ b/vendor/golang.org/x/oauth2/README.md
@@ -0,0 +1,35 @@
+# OAuth2 for Go
+
+[![Go Reference](https://pkg.go.dev/badge/golang.org/x/oauth2.svg)](https://pkg.go.dev/golang.org/x/oauth2)
+[![Build Status](https://travis-ci.org/golang/oauth2.svg?branch=master)](https://travis-ci.org/golang/oauth2)
+
+oauth2 package contains a client implementation for OAuth 2.0 spec.
+
+See pkg.go.dev for further documentation and examples.
+
+* [pkg.go.dev/golang.org/x/oauth2](https://pkg.go.dev/golang.org/x/oauth2)
+* [pkg.go.dev/golang.org/x/oauth2/google](https://pkg.go.dev/golang.org/x/oauth2/google)
+
+## Policy for new endpoints
+
+We no longer accept new provider-specific packages in this repo if all
+they do is add a single endpoint variable. If you just want to add a
+single endpoint, add it to the
+[pkg.go.dev/golang.org/x/oauth2/endpoints](https://pkg.go.dev/golang.org/x/oauth2/endpoints)
+package.
+
+## Report Issues / Send Patches
+
+The main issue tracker for the oauth2 repository is located at
+https://github.com/golang/oauth2/issues.
+
+This repository uses Gerrit for code changes. To learn how to submit changes to
+this repository, see https://go.dev/doc/contribute.
+
+The git repository is https://go.googlesource.com/oauth2.
+
+Note:
+
+* Excluding trivial changes, all contributions should be connected to an existing issue.
+* API changes must go through the [change proposal process](https://go.dev/s/proposal-process) before they can be accepted.
+* The code owners are listed at [dev.golang.org/owners](https://dev.golang.org/owners#:~:text=x/oauth2).
diff --git a/vendor/golang.org/x/oauth2/deviceauth.go b/vendor/golang.org/x/oauth2/deviceauth.go
new file mode 100644
index 0000000..e99c92f
--- /dev/null
+++ b/vendor/golang.org/x/oauth2/deviceauth.go
@@ -0,0 +1,198 @@
+package oauth2
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+	"time"
+
+	"golang.org/x/oauth2/internal"
+)
+
+// https://datatracker.ietf.org/doc/html/rfc8628#section-3.5
+const (
+	errAuthorizationPending = "authorization_pending"
+	errSlowDown             = "slow_down"
+	errAccessDenied         = "access_denied"
+	errExpiredToken         = "expired_token"
+)
+
+// DeviceAuthResponse describes a successful RFC 8628 Device Authorization Response
+// https://datatracker.ietf.org/doc/html/rfc8628#section-3.2
+type DeviceAuthResponse struct {
+	// DeviceCode
+	DeviceCode string `json:"device_code"`
+	// UserCode is the code the user should enter at the verification uri
+	UserCode string `json:"user_code"`
+	// VerificationURI is where user should enter the user code
+	VerificationURI string `json:"verification_uri"`
+	// VerificationURIComplete (if populated) includes the user code in the verification URI. This is typically shown to the user in non-textual form, such as a QR code.
+	VerificationURIComplete string `json:"verification_uri_complete,omitempty"`
+	// Expiry is when the device code and user code expire
+	Expiry time.Time `json:"expires_in,omitempty"`
+	// Interval is the duration in seconds that Poll should wait between requests
+	Interval int64 `json:"interval,omitempty"`
+}
+
+func (d DeviceAuthResponse) MarshalJSON() ([]byte, error) {
+	type Alias DeviceAuthResponse
+	var expiresIn int64
+	if !d.Expiry.IsZero() {
+		expiresIn = int64(time.Until(d.Expiry).Seconds())
+	}
+	return json.Marshal(&struct {
+		ExpiresIn int64 `json:"expires_in,omitempty"`
+		*Alias
+	}{
+		ExpiresIn: expiresIn,
+		Alias:     (*Alias)(&d),
+	})
+
+}
+
+func (c *DeviceAuthResponse) UnmarshalJSON(data []byte) error {
+	type Alias DeviceAuthResponse
+	aux := &struct {
+		ExpiresIn int64 `json:"expires_in"`
+		// workaround misspelling of verification_uri
+		VerificationURL string `json:"verification_url"`
+		*Alias
+	}{
+		Alias: (*Alias)(c),
+	}
+	if err := json.Unmarshal(data, &aux); err != nil {
+		return err
+	}
+	if aux.ExpiresIn != 0 {
+		c.Expiry = time.Now().UTC().Add(time.Second * time.Duration(aux.ExpiresIn))
+	}
+	if c.VerificationURI == "" {
+		c.VerificationURI = aux.VerificationURL
+	}
+	return nil
+}
+
+// DeviceAuth returns a device auth struct which contains a device code
+// and authorization information provided for users to enter on another device.
+func (c *Config) DeviceAuth(ctx context.Context, opts ...AuthCodeOption) (*DeviceAuthResponse, error) {
+	// https://datatracker.ietf.org/doc/html/rfc8628#section-3.1
+	v := url.Values{
+		"client_id": {c.ClientID},
+	}
+	if len(c.Scopes) > 0 {
+		v.Set("scope", strings.Join(c.Scopes, " "))
+	}
+	for _, opt := range opts {
+		opt.setValue(v)
+	}
+	return retrieveDeviceAuth(ctx, c, v)
+}
+
+func retrieveDeviceAuth(ctx context.Context, c *Config, v url.Values) (*DeviceAuthResponse, error) {
+	if c.Endpoint.DeviceAuthURL == "" {
+		return nil, errors.New("endpoint missing DeviceAuthURL")
+	}
+
+	req, err := http.NewRequest("POST", c.Endpoint.DeviceAuthURL, strings.NewReader(v.Encode()))
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+	req.Header.Set("Accept", "application/json")
+
+	t := time.Now()
+	r, err := internal.ContextClient(ctx).Do(req)
+	if err != nil {
+		return nil, err
+	}
+
+	body, err := io.ReadAll(io.LimitReader(r.Body, 1<<20))
+	if err != nil {
+		return nil, fmt.Errorf("oauth2: cannot auth device: %v", err)
+	}
+	if code := r.StatusCode; code < 200 || code > 299 {
+		return nil, &RetrieveError{
+			Response: r,
+			Body:     body,
+		}
+	}
+
+	da := &DeviceAuthResponse{}
+	err = json.Unmarshal(body, &da)
+	if err != nil {
+		return nil, fmt.Errorf("unmarshal %s", err)
+	}
+
+	if !da.Expiry.IsZero() {
+		// Make a small adjustment to account for time taken by the request
+		da.Expiry = da.Expiry.Add(-time.Since(t))
+	}
+
+	return da, nil
+}
+
+// DeviceAccessToken polls the server to exchange a device code for a token.
+func (c *Config) DeviceAccessToken(ctx context.Context, da *DeviceAuthResponse, opts ...AuthCodeOption) (*Token, error) {
+	if !da.Expiry.IsZero() {
+		var cancel context.CancelFunc
+		ctx, cancel = context.WithDeadline(ctx, da.Expiry)
+		defer cancel()
+	}
+
+	// https://datatracker.ietf.org/doc/html/rfc8628#section-3.4
+	v := url.Values{
+		"client_id":   {c.ClientID},
+		"grant_type":  {"urn:ietf:params:oauth:grant-type:device_code"},
+		"device_code": {da.DeviceCode},
+	}
+	if len(c.Scopes) > 0 {
+		v.Set("scope", strings.Join(c.Scopes, " "))
+	}
+	for _, opt := range opts {
+		opt.setValue(v)
+	}
+
+	// "If no value is provided, clients MUST use 5 as the default."
+	// https://datatracker.ietf.org/doc/html/rfc8628#section-3.2
+	interval := da.Interval
+	if interval == 0 {
+		interval = 5
+	}
+
+	ticker := time.NewTicker(time.Duration(interval) * time.Second)
+	defer ticker.Stop()
+	for {
+		select {
+		case <-ctx.Done():
+			return nil, ctx.Err()
+		case <-ticker.C:
+			tok, err := retrieveToken(ctx, c, v)
+			if err == nil {
+				return tok, nil
+			}
+
+			e, ok := err.(*RetrieveError)
+			if !ok {
+				return nil, err
+			}
+			switch e.ErrorCode {
+			case errSlowDown:
+				// https://datatracker.ietf.org/doc/html/rfc8628#section-3.5
+				// "the interval MUST be increased by 5 seconds for this and all subsequent requests"
+				interval += 5
+				ticker.Reset(time.Duration(interval) * time.Second)
+			case errAuthorizationPending:
+				// Do nothing.
+			case errAccessDenied, errExpiredToken:
+				fallthrough
+			default:
+				return tok, err
+			}
+		}
+	}
+}
diff --git a/vendor/golang.org/x/oauth2/internal/doc.go b/vendor/golang.org/x/oauth2/internal/doc.go
new file mode 100644
index 0000000..8c7c475
--- /dev/null
+++ b/vendor/golang.org/x/oauth2/internal/doc.go
@@ -0,0 +1,6 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package internal contains support packages for [golang.org/x/oauth2].
+package internal
diff --git a/vendor/golang.org/x/oauth2/internal/oauth2.go b/vendor/golang.org/x/oauth2/internal/oauth2.go
new file mode 100644
index 0000000..71ea6ad
--- /dev/null
+++ b/vendor/golang.org/x/oauth2/internal/oauth2.go
@@ -0,0 +1,37 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package internal
+
+import (
+	"crypto/rsa"
+	"crypto/x509"
+	"encoding/pem"
+	"errors"
+	"fmt"
+)
+
+// ParseKey converts the binary contents of a private key file
+// to an [*rsa.PrivateKey]. It detects whether the private key is in a
+// PEM container or not. If so, it extracts the private key
+// from PEM container before conversion. It only supports PEM
+// containers with no passphrase.
+func ParseKey(key []byte) (*rsa.PrivateKey, error) {
+	block, _ := pem.Decode(key)
+	if block != nil {
+		key = block.Bytes
+	}
+	parsedKey, err := x509.ParsePKCS8PrivateKey(key)
+	if err != nil {
+		parsedKey, err = x509.ParsePKCS1PrivateKey(key)
+		if err != nil {
+			return nil, fmt.Errorf("private key should be a PEM or plain PKCS1 or PKCS8; parse error: %v", err)
+		}
+	}
+	parsed, ok := parsedKey.(*rsa.PrivateKey)
+	if !ok {
+		return nil, errors.New("private key is invalid")
+	}
+	return parsed, nil
+}
diff --git a/vendor/golang.org/x/oauth2/internal/token.go b/vendor/golang.org/x/oauth2/internal/token.go
new file mode 100644
index 0000000..8389f24
--- /dev/null
+++ b/vendor/golang.org/x/oauth2/internal/token.go
@@ -0,0 +1,356 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package internal
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"math"
+	"mime"
+	"net/http"
+	"net/url"
+	"strconv"
+	"strings"
+	"sync"
+	"sync/atomic"
+	"time"
+)
+
+// Token represents the credentials used to authorize
+// the requests to access protected resources on the OAuth 2.0
+// provider's backend.
+//
+// This type is a mirror of [golang.org/x/oauth2.Token] and exists to break
+// an otherwise-circular dependency. Other internal packages
+// should convert this Token into an [golang.org/x/oauth2.Token] before use.
+type Token struct {
+	// AccessToken is the token that authorizes and authenticates
+	// the requests.
+	AccessToken string
+
+	// TokenType is the type of token.
+	// The Type method returns either this or "Bearer", the default.
+	TokenType string
+
+	// RefreshToken is a token that's used by the application
+	// (as opposed to the user) to refresh the access token
+	// if it expires.
+	RefreshToken string
+
+	// Expiry is the optional expiration time of the access token.
+	//
+	// If zero, TokenSource implementations will reuse the same
+	// token forever and RefreshToken or equivalent
+	// mechanisms for that TokenSource will not be used.
+	Expiry time.Time
+
+	// ExpiresIn is the OAuth2 wire format "expires_in" field,
+	// which specifies how many seconds later the token expires,
+	// relative to an unknown time base approximately around "now".
+	// It is the application's responsibility to populate
+	// `Expiry` from `ExpiresIn` when required.
+	ExpiresIn int64 `json:"expires_in,omitempty"`
+
+	// Raw optionally contains extra metadata from the server
+	// when updating a token.
+	Raw any
+}
+
+// tokenJSON is the struct representing the HTTP response from OAuth2
+// providers returning a token or error in JSON form.
+// https://datatracker.ietf.org/doc/html/rfc6749#section-5.1
+type tokenJSON struct {
+	AccessToken  string         `json:"access_token"`
+	TokenType    string         `json:"token_type"`
+	RefreshToken string         `json:"refresh_token"`
+	ExpiresIn    expirationTime `json:"expires_in"` // at least PayPal returns string, while most return number
+	// error fields
+	// https://datatracker.ietf.org/doc/html/rfc6749#section-5.2
+	ErrorCode        string `json:"error"`
+	ErrorDescription string `json:"error_description"`
+	ErrorURI         string `json:"error_uri"`
+}
+
+func (e *tokenJSON) expiry() (t time.Time) {
+	if v := e.ExpiresIn; v != 0 {
+		return time.Now().Add(time.Duration(v) * time.Second)
+	}
+	return
+}
+
+type expirationTime int32
+
+func (e *expirationTime) UnmarshalJSON(b []byte) error {
+	if len(b) == 0 || string(b) == "null" {
+		return nil
+	}
+	var n json.Number
+	err := json.Unmarshal(b, &n)
+	if err != nil {
+		return err
+	}
+	i, err := n.Int64()
+	if err != nil {
+		return err
+	}
+	if i > math.MaxInt32 {
+		i = math.MaxInt32
+	}
+	*e = expirationTime(i)
+	return nil
+}
+
+// AuthStyle is a copy of the golang.org/x/oauth2 package's AuthStyle type.
+type AuthStyle int
+
+const (
+	AuthStyleUnknown  AuthStyle = 0
+	AuthStyleInParams AuthStyle = 1
+	AuthStyleInHeader AuthStyle = 2
+)
+
+// LazyAuthStyleCache is a backwards compatibility compromise to let Configs
+// have a lazily-initialized AuthStyleCache.
+//
+// The two users of this, oauth2.Config and oauth2/clientcredentials.Config,
+// both would ideally just embed an unexported AuthStyleCache but because both
+// were historically allowed to be copied by value we can't retroactively add an
+// uncopyable Mutex to them.
+//
+// We could use an atomic.Pointer, but that was added recently enough (in Go
+// 1.18) that we'd break Go 1.17 users where the tests as of 2023-08-03
+// still pass. By using an atomic.Value, it supports both Go 1.17 and
+// copying by value, even if that's not ideal.
+type LazyAuthStyleCache struct {
+	v atomic.Value // of *AuthStyleCache
+}
+
+func (lc *LazyAuthStyleCache) Get() *AuthStyleCache {
+	if c, ok := lc.v.Load().(*AuthStyleCache); ok {
+		return c
+	}
+	c := new(AuthStyleCache)
+	if !lc.v.CompareAndSwap(nil, c) {
+		c = lc.v.Load().(*AuthStyleCache)
+	}
+	return c
+}
+
+type authStyleCacheKey struct {
+	url      string
+	clientID string
+}
+
+// AuthStyleCache is the set of tokenURLs we've successfully used via
+// RetrieveToken and which style auth we ended up using.
+// It's called a cache, but it doesn't (yet?) shrink. It's expected that
+// the set of OAuth2 servers a program contacts over time is fixed and
+// small.
+type AuthStyleCache struct {
+	mu sync.Mutex
+	m  map[authStyleCacheKey]AuthStyle
+}
+
+// lookupAuthStyle reports which auth style we last used with tokenURL
+// when calling RetrieveToken and whether we have ever done so.
+func (c *AuthStyleCache) lookupAuthStyle(tokenURL, clientID string) (style AuthStyle, ok bool) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	style, ok = c.m[authStyleCacheKey{tokenURL, clientID}]
+	return
+}
+
+// setAuthStyle adds an entry to authStyleCache, documented above.
+func (c *AuthStyleCache) setAuthStyle(tokenURL, clientID string, v AuthStyle) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	if c.m == nil {
+		c.m = make(map[authStyleCacheKey]AuthStyle)
+	}
+	c.m[authStyleCacheKey{tokenURL, clientID}] = v
+}
+
+// newTokenRequest returns a new *http.Request to retrieve a new token
+// from tokenURL using the provided clientID, clientSecret, and POST
+// body parameters.
+//
+// inParams is whether the clientID & clientSecret should be encoded
+// as the POST body. An 'inParams' value of true means to send it in
+// the POST body (along with any values in v); false means to send it
+// in the Authorization header.
+func newTokenRequest(tokenURL, clientID, clientSecret string, v url.Values, authStyle AuthStyle) (*http.Request, error) {
+	if authStyle == AuthStyleInParams {
+		v = cloneURLValues(v)
+		if clientID != "" {
+			v.Set("client_id", clientID)
+		}
+		if clientSecret != "" {
+			v.Set("client_secret", clientSecret)
+		}
+	}
+	req, err := http.NewRequest("POST", tokenURL, strings.NewReader(v.Encode()))
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+	if authStyle == AuthStyleInHeader {
+		req.SetBasicAuth(url.QueryEscape(clientID), url.QueryEscape(clientSecret))
+	}
+	return req, nil
+}
+
+func cloneURLValues(v url.Values) url.Values {
+	v2 := make(url.Values, len(v))
+	for k, vv := range v {
+		v2[k] = append([]string(nil), vv...)
+	}
+	return v2
+}
+
+func RetrieveToken(ctx context.Context, clientID, clientSecret, tokenURL string, v url.Values, authStyle AuthStyle, styleCache *AuthStyleCache) (*Token, error) {
+	needsAuthStyleProbe := authStyle == AuthStyleUnknown
+	if needsAuthStyleProbe {
+		if style, ok := styleCache.lookupAuthStyle(tokenURL, clientID); ok {
+			authStyle = style
+			needsAuthStyleProbe = false
+		} else {
+			authStyle = AuthStyleInHeader // the first way we'll try
+		}
+	}
+	req, err := newTokenRequest(tokenURL, clientID, clientSecret, v, authStyle)
+	if err != nil {
+		return nil, err
+	}
+	token, err := doTokenRoundTrip(ctx, req)
+	if err != nil && needsAuthStyleProbe {
+		// If we get an error, assume the server wants the
+		// clientID & clientSecret in a different form.
+		// See https://code.google.com/p/goauth2/issues/detail?id=31 for background.
+		// In summary:
+		// - Reddit only accepts client secret in the Authorization header
+		// - Dropbox accepts either it in URL param or Auth header, but not both.
+		// - Google only accepts URL param (not spec compliant?), not Auth header
+		// - Stripe only accepts client secret in Auth header with Bearer method, not Basic
+		//
+		// We used to maintain a big table in this code of all the sites and which way
+		// they went, but maintaining it didn't scale & got annoying.
+		// So just try both ways.
+		authStyle = AuthStyleInParams // the second way we'll try
+		req, _ = newTokenRequest(tokenURL, clientID, clientSecret, v, authStyle)
+		token, err = doTokenRoundTrip(ctx, req)
+	}
+	if needsAuthStyleProbe && err == nil {
+		styleCache.setAuthStyle(tokenURL, clientID, authStyle)
+	}
+	// Don't overwrite `RefreshToken` with an empty value
+	// if this was a token refreshing request.
+	if token != nil && token.RefreshToken == "" {
+		token.RefreshToken = v.Get("refresh_token")
+	}
+	return token, err
+}
+
+func doTokenRoundTrip(ctx context.Context, req *http.Request) (*Token, error) {
+	r, err := ContextClient(ctx).Do(req.WithContext(ctx))
+	if err != nil {
+		return nil, err
+	}
+	body, err := io.ReadAll(io.LimitReader(r.Body, 1<<20))
+	r.Body.Close()
+	if err != nil {
+		return nil, fmt.Errorf("oauth2: cannot fetch token: %v", err)
+	}
+
+	failureStatus := r.StatusCode < 200 || r.StatusCode > 299
+	retrieveError := &RetrieveError{
+		Response: r,
+		Body:     body,
+		// attempt to populate error detail below
+	}
+
+	var token *Token
+	content, _, _ := mime.ParseMediaType(r.Header.Get("Content-Type"))
+	switch content {
+	case "application/x-www-form-urlencoded", "text/plain":
+		// some endpoints return a query string
+		vals, err := url.ParseQuery(string(body))
+		if err != nil {
+			if failureStatus {
+				return nil, retrieveError
+			}
+			return nil, fmt.Errorf("oauth2: cannot parse response: %v", err)
+		}
+		retrieveError.ErrorCode = vals.Get("error")
+		retrieveError.ErrorDescription = vals.Get("error_description")
+		retrieveError.ErrorURI = vals.Get("error_uri")
+		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 {
+			if failureStatus {
+				return nil, retrieveError
+			}
+			return nil, fmt.Errorf("oauth2: cannot parse json: %v", err)
+		}
+		retrieveError.ErrorCode = tj.ErrorCode
+		retrieveError.ErrorDescription = tj.ErrorDescription
+		retrieveError.ErrorURI = tj.ErrorURI
+		token = &Token{
+			AccessToken:  tj.AccessToken,
+			TokenType:    tj.TokenType,
+			RefreshToken: tj.RefreshToken,
+			Expiry:       tj.expiry(),
+			ExpiresIn:    int64(tj.ExpiresIn),
+			Raw:          make(map[string]any),
+		}
+		json.Unmarshal(body, &token.Raw) // no error checks for optional fields
+	}
+	// according to spec, servers should respond status 400 in error case
+	// https://www.rfc-editor.org/rfc/rfc6749#section-5.2
+	// but some unorthodox servers respond 200 in error case
+	if failureStatus || retrieveError.ErrorCode != "" {
+		return nil, retrieveError
+	}
+	if token.AccessToken == "" {
+		return nil, errors.New("oauth2: server response missing access_token")
+	}
+	return token, nil
+}
+
+// mirrors oauth2.RetrieveError
+type RetrieveError struct {
+	Response         *http.Response
+	Body             []byte
+	ErrorCode        string
+	ErrorDescription string
+	ErrorURI         string
+}
+
+func (r *RetrieveError) Error() string {
+	if r.ErrorCode != "" {
+		s := fmt.Sprintf("oauth2: %q", r.ErrorCode)
+		if r.ErrorDescription != "" {
+			s += fmt.Sprintf(" %q", r.ErrorDescription)
+		}
+		if r.ErrorURI != "" {
+			s += fmt.Sprintf(" %q", r.ErrorURI)
+		}
+		return s
+	}
+	return fmt.Sprintf("oauth2: cannot fetch token: %v\nResponse: %s", r.Response.Status, r.Body)
+}
diff --git a/vendor/golang.org/x/oauth2/internal/transport.go b/vendor/golang.org/x/oauth2/internal/transport.go
new file mode 100644
index 0000000..afc0aeb
--- /dev/null
+++ b/vendor/golang.org/x/oauth2/internal/transport.go
@@ -0,0 +1,28 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package internal
+
+import (
+	"context"
+	"net/http"
+)
+
+// HTTPClient is the context key to use with [context.WithValue]
+// to associate an [*http.Client] value with a context.
+var HTTPClient ContextKey
+
+// ContextKey is just an empty struct. It exists so HTTPClient can be
+// an immutable public variable with a unique type. It's immutable
+// because nobody else can create a ContextKey, being unexported.
+type ContextKey struct{}
+
+func ContextClient(ctx context.Context) *http.Client {
+	if ctx != nil {
+		if hc, ok := ctx.Value(HTTPClient).(*http.Client); ok {
+			return hc
+		}
+	}
+	return http.DefaultClient
+}
diff --git a/vendor/golang.org/x/oauth2/oauth2.go b/vendor/golang.org/x/oauth2/oauth2.go
new file mode 100644
index 0000000..de34feb
--- /dev/null
+++ b/vendor/golang.org/x/oauth2/oauth2.go
@@ -0,0 +1,424 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package oauth2 provides support for making
+// OAuth2 authorized and authenticated HTTP requests,
+// as specified in RFC 6749.
+// It can additionally grant authorization with Bearer JWT.
+package oauth2 // import "golang.org/x/oauth2"
+
+import (
+	"bytes"
+	"context"
+	"errors"
+	"net/http"
+	"net/url"
+	"strings"
+	"sync"
+	"time"
+
+	"golang.org/x/oauth2/internal"
+)
+
+// NoContext is the default context you should supply if not using
+// your own [context.Context].
+//
+// Deprecated: Use [context.Background] or [context.TODO] instead.
+var NoContext = context.TODO()
+
+// RegisterBrokenAuthHeaderProvider previously did something. It is now a no-op.
+//
+// Deprecated: this function no longer does anything. Caller code that
+// wants to avoid potential extra HTTP requests made during
+// auto-probing of the provider's auth style should set
+// Endpoint.AuthStyle.
+func RegisterBrokenAuthHeaderProvider(tokenURL string) {}
+
+// Config describes a typical 3-legged OAuth2 flow, with both the
+// client application information and the server's endpoint URLs.
+// For the client credentials 2-legged OAuth2 flow, see the
+// [golang.org/x/oauth2/clientcredentials] package.
+type Config struct {
+	// ClientID is the application's ID.
+	ClientID string
+
+	// ClientSecret is the application's secret.
+	ClientSecret string
+
+	// Endpoint contains the authorization server's token endpoint
+	// URLs. These are constants specific to each server and are
+	// often available via site-specific packages, such as
+	// google.Endpoint or github.Endpoint.
+	Endpoint Endpoint
+
+	// RedirectURL is the URL to redirect users going through
+	// the OAuth flow, after the resource owner's URLs.
+	RedirectURL string
+
+	// Scopes specifies optional requested permissions.
+	Scopes []string
+
+	// authStyleCache caches which auth style to use when Endpoint.AuthStyle is
+	// the zero value (AuthStyleAutoDetect).
+	authStyleCache internal.LazyAuthStyleCache
+}
+
+// A TokenSource is anything that can return a token.
+type TokenSource interface {
+	// Token returns a token or an error.
+	// Token must be safe for concurrent use by multiple goroutines.
+	// The returned Token must not be modified.
+	Token() (*Token, error)
+}
+
+// Endpoint represents an OAuth 2.0 provider's authorization and token
+// endpoint URLs.
+type Endpoint struct {
+	AuthURL       string
+	DeviceAuthURL string
+	TokenURL      string
+
+	// AuthStyle optionally specifies how the endpoint wants the
+	// client ID & client secret sent. The zero value means to
+	// auto-detect.
+	AuthStyle AuthStyle
+}
+
+// AuthStyle represents how requests for tokens are authenticated
+// to the server.
+type AuthStyle int
+
+const (
+	// AuthStyleAutoDetect means to auto-detect which authentication
+	// style the provider wants by trying both ways and caching
+	// the successful way for the future.
+	AuthStyleAutoDetect AuthStyle = 0
+
+	// AuthStyleInParams sends the "client_id" and "client_secret"
+	// in the POST body as application/x-www-form-urlencoded parameters.
+	AuthStyleInParams AuthStyle = 1
+
+	// AuthStyleInHeader sends the client_id and client_password
+	// using HTTP Basic Authorization. This is an optional style
+	// described in the OAuth2 RFC 6749 section 2.3.1.
+	AuthStyleInHeader AuthStyle = 2
+)
+
+var (
+	// AccessTypeOnline and AccessTypeOffline are options passed
+	// to the Options.AuthCodeURL method. They modify the
+	// "access_type" field that gets sent in the URL returned by
+	// AuthCodeURL.
+	//
+	// Online is the default if neither is specified. If your
+	// application needs to refresh access tokens when the user
+	// is not present at the browser, then use offline. This will
+	// result in your application obtaining a refresh token the
+	// first time your application exchanges an authorization
+	// code for a user.
+	AccessTypeOnline  AuthCodeOption = SetAuthURLParam("access_type", "online")
+	AccessTypeOffline AuthCodeOption = SetAuthURLParam("access_type", "offline")
+
+	// ApprovalForce forces the users to view the consent dialog
+	// and confirm the permissions request at the URL returned
+	// from AuthCodeURL, even if they've already done so.
+	ApprovalForce AuthCodeOption = SetAuthURLParam("prompt", "consent")
+)
+
+// An AuthCodeOption is passed to Config.AuthCodeURL.
+type AuthCodeOption interface {
+	setValue(url.Values)
+}
+
+type setParam struct{ k, v string }
+
+func (p setParam) setValue(m url.Values) { m.Set(p.k, p.v) }
+
+// SetAuthURLParam builds an [AuthCodeOption] which passes key/value parameters
+// to a provider's authorization endpoint.
+func SetAuthURLParam(key, value string) AuthCodeOption {
+	return setParam{key, value}
+}
+
+// AuthCodeURL returns a URL to OAuth 2.0 provider's consent page
+// that asks for permissions for the required scopes explicitly.
+//
+// State is an opaque value used by the client to maintain state between the
+// request and callback. The authorization server includes this value when
+// redirecting the user agent back to the client.
+//
+// Opts may include [AccessTypeOnline] or [AccessTypeOffline], as well
+// as [ApprovalForce].
+//
+// To protect against CSRF attacks, opts should include a PKCE challenge
+// (S256ChallengeOption). Not all servers support PKCE. An alternative is to
+// generate a random state parameter and verify it after exchange.
+// See https://datatracker.ietf.org/doc/html/rfc6749#section-10.12 (predating
+// PKCE), https://www.oauth.com/oauth2-servers/pkce/ and
+// https://www.ietf.org/archive/id/draft-ietf-oauth-v2-1-09.html#name-cross-site-request-forgery (describing both approaches)
+func (c *Config) AuthCodeURL(state string, opts ...AuthCodeOption) string {
+	var buf bytes.Buffer
+	buf.WriteString(c.Endpoint.AuthURL)
+	v := url.Values{
+		"response_type": {"code"},
+		"client_id":     {c.ClientID},
+	}
+	if c.RedirectURL != "" {
+		v.Set("redirect_uri", c.RedirectURL)
+	}
+	if len(c.Scopes) > 0 {
+		v.Set("scope", strings.Join(c.Scopes, " "))
+	}
+	if state != "" {
+		v.Set("state", state)
+	}
+	for _, opt := range opts {
+		opt.setValue(v)
+	}
+	if strings.Contains(c.Endpoint.AuthURL, "?") {
+		buf.WriteByte('&')
+	} else {
+		buf.WriteByte('?')
+	}
+	buf.WriteString(v.Encode())
+	return buf.String()
+}
+
+// PasswordCredentialsToken converts a resource owner username and password
+// pair into a token.
+//
+// Per the RFC, this grant type should only be used "when there is a high
+// degree of trust between the resource owner and the client (e.g., the client
+// is part of the device operating system or a highly privileged application),
+// and when other authorization grant types are not available."
+// See https://tools.ietf.org/html/rfc6749#section-4.3 for more info.
+//
+// The provided context optionally controls which HTTP client is used. See the [HTTPClient] variable.
+func (c *Config) PasswordCredentialsToken(ctx context.Context, username, password string) (*Token, error) {
+	v := url.Values{
+		"grant_type": {"password"},
+		"username":   {username},
+		"password":   {password},
+	}
+	if len(c.Scopes) > 0 {
+		v.Set("scope", strings.Join(c.Scopes, " "))
+	}
+	return retrieveToken(ctx, c, v)
+}
+
+// Exchange converts an authorization code into a token.
+//
+// It is used after a resource provider redirects the user back
+// to the Redirect URI (the URL obtained from AuthCodeURL).
+//
+// The provided context optionally controls which HTTP client is used. See the [HTTPClient] variable.
+//
+// The code will be in the [http.Request.FormValue]("code"). Before
+// calling Exchange, be sure to validate [http.Request.FormValue]("state") if you are
+// using it to protect against CSRF attacks.
+//
+// If using PKCE to protect against CSRF attacks, opts should include a
+// VerifierOption.
+func (c *Config) Exchange(ctx context.Context, code string, opts ...AuthCodeOption) (*Token, error) {
+	v := url.Values{
+		"grant_type": {"authorization_code"},
+		"code":       {code},
+	}
+	if c.RedirectURL != "" {
+		v.Set("redirect_uri", c.RedirectURL)
+	}
+	for _, opt := range opts {
+		opt.setValue(v)
+	}
+	return retrieveToken(ctx, c, v)
+}
+
+// Client returns an HTTP client using the provided token.
+// The token will auto-refresh as necessary. The underlying
+// HTTP transport will be obtained using the provided context.
+// The returned client and its Transport should not be modified.
+func (c *Config) Client(ctx context.Context, t *Token) *http.Client {
+	return NewClient(ctx, c.TokenSource(ctx, t))
+}
+
+// TokenSource returns a [TokenSource] that returns t until t expires,
+// automatically refreshing it as necessary using the provided context.
+//
+// Most users will use [Config.Client] instead.
+func (c *Config) TokenSource(ctx context.Context, t *Token) TokenSource {
+	tkr := &tokenRefresher{
+		ctx:  ctx,
+		conf: c,
+	}
+	if t != nil {
+		tkr.refreshToken = t.RefreshToken
+	}
+	return &reuseTokenSource{
+		t:   t,
+		new: tkr,
+	}
+}
+
+// tokenRefresher is a TokenSource that makes "grant_type=refresh_token"
+// HTTP requests to renew a token using a RefreshToken.
+type tokenRefresher struct {
+	ctx          context.Context // used to get HTTP requests
+	conf         *Config
+	refreshToken string
+}
+
+// WARNING: Token is not safe for concurrent access, as it
+// updates the tokenRefresher's refreshToken field.
+// Within this package, it is used by reuseTokenSource which
+// synchronizes calls to this method with its own mutex.
+func (tf *tokenRefresher) Token() (*Token, error) {
+	if tf.refreshToken == "" {
+		return nil, errors.New("oauth2: token expired and refresh token is not set")
+	}
+
+	tk, err := retrieveToken(tf.ctx, tf.conf, url.Values{
+		"grant_type":    {"refresh_token"},
+		"refresh_token": {tf.refreshToken},
+	})
+
+	if err != nil {
+		return nil, err
+	}
+	if tf.refreshToken != tk.RefreshToken {
+		tf.refreshToken = tk.RefreshToken
+	}
+	return tk, nil
+}
+
+// reuseTokenSource is a TokenSource that holds a single token in memory
+// and validates its expiry before each call to retrieve it with
+// Token. If it's expired, it will be auto-refreshed using the
+// new TokenSource.
+type reuseTokenSource struct {
+	new TokenSource // called when t is expired.
+
+	mu sync.Mutex // guards t
+	t  *Token
+
+	expiryDelta time.Duration
+}
+
+// Token returns the current token if it's still valid, else will
+// refresh the current token and return the new one.
+func (s *reuseTokenSource) Token() (*Token, error) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if s.t.Valid() {
+		return s.t, nil
+	}
+	t, err := s.new.Token()
+	if err != nil {
+		return nil, err
+	}
+	t.expiryDelta = s.expiryDelta
+	s.t = t
+	return t, nil
+}
+
+// StaticTokenSource returns a [TokenSource] that always returns the same token.
+// Because the provided token t is never refreshed, StaticTokenSource is only
+// useful for tokens that never expire.
+func StaticTokenSource(t *Token) TokenSource {
+	return staticTokenSource{t}
+}
+
+// staticTokenSource is a TokenSource that always returns the same Token.
+type staticTokenSource struct {
+	t *Token
+}
+
+func (s staticTokenSource) Token() (*Token, error) {
+	return s.t, nil
+}
+
+// HTTPClient is the context key to use with [context.WithValue]
+// to associate a [*http.Client] value with a context.
+var HTTPClient internal.ContextKey
+
+// NewClient creates an [*http.Client] from a [context.Context] and [TokenSource].
+// The returned client is not valid beyond the lifetime of the context.
+//
+// Note that if a custom [*http.Client] is provided via the [context.Context] it
+// is used only for token acquisition and is not used to configure the
+// [*http.Client] returned from NewClient.
+//
+// As a special case, if src is nil, a non-OAuth2 client is returned
+// using the provided context. This exists to support related OAuth2
+// packages.
+func NewClient(ctx context.Context, src TokenSource) *http.Client {
+	if src == nil {
+		return internal.ContextClient(ctx)
+	}
+	cc := internal.ContextClient(ctx)
+	return &http.Client{
+		Transport: &Transport{
+			Base:   cc.Transport,
+			Source: ReuseTokenSource(nil, src),
+		},
+		CheckRedirect: cc.CheckRedirect,
+		Jar:           cc.Jar,
+		Timeout:       cc.Timeout,
+	}
+}
+
+// ReuseTokenSource returns a [TokenSource] which repeatedly returns the
+// same token as long as it's valid, starting with t.
+// When its cached token is invalid, a new token is obtained from src.
+//
+// ReuseTokenSource is typically used to reuse tokens from a cache
+// (such as a file on disk) between runs of a program, rather than
+// obtaining new tokens unnecessarily.
+//
+// The initial token t may be nil, in which case the [TokenSource] is
+// wrapped in a caching version if it isn't one already. This also
+// means it's always safe to wrap ReuseTokenSource around any other
+// [TokenSource] without adverse effects.
+func ReuseTokenSource(t *Token, src TokenSource) TokenSource {
+	// Don't wrap a reuseTokenSource in itself. That would work,
+	// but cause an unnecessary number of mutex operations.
+	// Just build the equivalent one.
+	if rt, ok := src.(*reuseTokenSource); ok {
+		if t == nil {
+			// Just use it directly.
+			return rt
+		}
+		src = rt.new
+	}
+	return &reuseTokenSource{
+		t:   t,
+		new: src,
+	}
+}
+
+// ReuseTokenSourceWithExpiry returns a [TokenSource] that acts in the same manner as the
+// [TokenSource] returned by [ReuseTokenSource], except the expiry buffer is
+// configurable. The expiration time of a token is calculated as
+// t.Expiry.Add(-earlyExpiry).
+func ReuseTokenSourceWithExpiry(t *Token, src TokenSource, earlyExpiry time.Duration) TokenSource {
+	// Don't wrap a reuseTokenSource in itself. That would work,
+	// but cause an unnecessary number of mutex operations.
+	// Just build the equivalent one.
+	if rt, ok := src.(*reuseTokenSource); ok {
+		if t == nil {
+			// Just use it directly, but set the expiryDelta to earlyExpiry,
+			// so the behavior matches what the user expects.
+			rt.expiryDelta = earlyExpiry
+			return rt
+		}
+		src = rt.new
+	}
+	if t != nil {
+		t.expiryDelta = earlyExpiry
+	}
+	return &reuseTokenSource{
+		t:           t,
+		new:         src,
+		expiryDelta: earlyExpiry,
+	}
+}
diff --git a/vendor/golang.org/x/oauth2/pkce.go b/vendor/golang.org/x/oauth2/pkce.go
new file mode 100644
index 0000000..cea8374
--- /dev/null
+++ b/vendor/golang.org/x/oauth2/pkce.go
@@ -0,0 +1,69 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package oauth2
+
+import (
+	"crypto/rand"
+	"crypto/sha256"
+	"encoding/base64"
+	"net/url"
+)
+
+const (
+	codeChallengeKey       = "code_challenge"
+	codeChallengeMethodKey = "code_challenge_method"
+	codeVerifierKey        = "code_verifier"
+)
+
+// GenerateVerifier generates a PKCE code verifier with 32 octets of randomness.
+// This follows recommendations in RFC 7636.
+//
+// A fresh verifier should be generated for each authorization.
+// The resulting verifier should be passed to [Config.AuthCodeURL] or [Config.DeviceAuth]
+// with [S256ChallengeOption], and to [Config.Exchange] or [Config.DeviceAccessToken]
+// with [VerifierOption].
+func GenerateVerifier() string {
+	// "RECOMMENDED that the output of a suitable random number generator be
+	// used to create a 32-octet sequence.  The octet sequence is then
+	// base64url-encoded to produce a 43-octet URL-safe string to use as the
+	// code verifier."
+	// https://datatracker.ietf.org/doc/html/rfc7636#section-4.1
+	data := make([]byte, 32)
+	if _, err := rand.Read(data); err != nil {
+		panic(err)
+	}
+	return base64.RawURLEncoding.EncodeToString(data)
+}
+
+// VerifierOption returns a PKCE code verifier [AuthCodeOption]. It should only be
+// passed to [Config.Exchange] or [Config.DeviceAccessToken].
+func VerifierOption(verifier string) AuthCodeOption {
+	return setParam{k: codeVerifierKey, v: verifier}
+}
+
+// S256ChallengeFromVerifier returns a PKCE code challenge derived from verifier with method S256.
+//
+// Prefer to use [S256ChallengeOption] where possible.
+func S256ChallengeFromVerifier(verifier string) string {
+	sha := sha256.Sum256([]byte(verifier))
+	return base64.RawURLEncoding.EncodeToString(sha[:])
+}
+
+// S256ChallengeOption derives a PKCE code challenge derived from verifier with
+// method S256. It should be passed to [Config.AuthCodeURL] or [Config.DeviceAuth]
+// only.
+func S256ChallengeOption(verifier string) AuthCodeOption {
+	return challengeOption{
+		challenge_method: "S256",
+		challenge:        S256ChallengeFromVerifier(verifier),
+	}
+}
+
+type challengeOption struct{ challenge_method, challenge string }
+
+func (p challengeOption) setValue(m url.Values) {
+	m.Set(codeChallengeMethodKey, p.challenge_method)
+	m.Set(codeChallengeKey, p.challenge)
+}
diff --git a/vendor/golang.org/x/oauth2/token.go b/vendor/golang.org/x/oauth2/token.go
new file mode 100644
index 0000000..239ec32
--- /dev/null
+++ b/vendor/golang.org/x/oauth2/token.go
@@ -0,0 +1,213 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package oauth2
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"net/url"
+	"strconv"
+	"strings"
+	"time"
+
+	"golang.org/x/oauth2/internal"
+)
+
+// defaultExpiryDelta determines how earlier a token should be considered
+// expired than its actual expiration time. It is used to avoid late
+// expirations due to client-server time mismatches.
+const defaultExpiryDelta = 10 * time.Second
+
+// Token represents the credentials used to authorize
+// the requests to access protected resources on the OAuth 2.0
+// provider's backend.
+//
+// Most users of this package should not access fields of Token
+// directly. They're exported mostly for use by related packages
+// implementing derivative OAuth2 flows.
+type Token struct {
+	// AccessToken is the token that authorizes and authenticates
+	// the requests.
+	AccessToken string `json:"access_token"`
+
+	// TokenType is the type of token.
+	// The Type method returns either this or "Bearer", the default.
+	TokenType string `json:"token_type,omitempty"`
+
+	// RefreshToken is a token that's used by the application
+	// (as opposed to the user) to refresh the access token
+	// if it expires.
+	RefreshToken string `json:"refresh_token,omitempty"`
+
+	// Expiry is the optional expiration time of the access token.
+	//
+	// If zero, [TokenSource] implementations will reuse the same
+	// token forever and RefreshToken or equivalent
+	// mechanisms for that TokenSource will not be used.
+	Expiry time.Time `json:"expiry,omitempty"`
+
+	// ExpiresIn is the OAuth2 wire format "expires_in" field,
+	// which specifies how many seconds later the token expires,
+	// relative to an unknown time base approximately around "now".
+	// It is the application's responsibility to populate
+	// `Expiry` from `ExpiresIn` when required.
+	ExpiresIn int64 `json:"expires_in,omitempty"`
+
+	// raw optionally contains extra metadata from the server
+	// when updating a token.
+	raw any
+
+	// expiryDelta is used to calculate when a token is considered
+	// expired, by subtracting from Expiry. If zero, defaultExpiryDelta
+	// is used.
+	expiryDelta time.Duration
+}
+
+// Type returns t.TokenType if non-empty, else "Bearer".
+func (t *Token) Type() string {
+	if strings.EqualFold(t.TokenType, "bearer") {
+		return "Bearer"
+	}
+	if strings.EqualFold(t.TokenType, "mac") {
+		return "MAC"
+	}
+	if strings.EqualFold(t.TokenType, "basic") {
+		return "Basic"
+	}
+	if t.TokenType != "" {
+		return t.TokenType
+	}
+	return "Bearer"
+}
+
+// SetAuthHeader sets the Authorization header to r using the access
+// token in t.
+//
+// This method is unnecessary when using [Transport] or an HTTP Client
+// returned by this package.
+func (t *Token) SetAuthHeader(r *http.Request) {
+	r.Header.Set("Authorization", t.Type()+" "+t.AccessToken)
+}
+
+// WithExtra returns a new [Token] that's a clone of t, but using the
+// provided raw extra map. This is only intended for use by packages
+// implementing derivative OAuth2 flows.
+func (t *Token) WithExtra(extra any) *Token {
+	t2 := new(Token)
+	*t2 = *t
+	t2.raw = extra
+	return t2
+}
+
+// Extra returns an extra field.
+// Extra fields are key-value pairs returned by the server as a
+// part of the token retrieval response.
+func (t *Token) Extra(key string) any {
+	if raw, ok := t.raw.(map[string]any); ok {
+		return raw[key]
+	}
+
+	vals, ok := t.raw.(url.Values)
+	if !ok {
+		return nil
+	}
+
+	v := vals.Get(key)
+	switch s := strings.TrimSpace(v); strings.Count(s, ".") {
+	case 0: // Contains no "."; try to parse as int
+		if i, err := strconv.ParseInt(s, 10, 64); err == nil {
+			return i
+		}
+	case 1: // Contains a single "."; try to parse as float
+		if f, err := strconv.ParseFloat(s, 64); err == nil {
+			return f
+		}
+	}
+
+	return v
+}
+
+// timeNow is time.Now but pulled out as a variable for tests.
+var timeNow = time.Now
+
+// expired reports whether the token is expired.
+// t must be non-nil.
+func (t *Token) expired() bool {
+	if t.Expiry.IsZero() {
+		return false
+	}
+
+	expiryDelta := defaultExpiryDelta
+	if t.expiryDelta != 0 {
+		expiryDelta = t.expiryDelta
+	}
+	return t.Expiry.Round(0).Add(-expiryDelta).Before(timeNow())
+}
+
+// Valid reports whether t is non-nil, has an AccessToken, and is not expired.
+func (t *Token) Valid() bool {
+	return t != nil && t.AccessToken != "" && !t.expired()
+}
+
+// tokenFromInternal maps an *internal.Token struct into
+// a *Token struct.
+func tokenFromInternal(t *internal.Token) *Token {
+	if t == nil {
+		return nil
+	}
+	return &Token{
+		AccessToken:  t.AccessToken,
+		TokenType:    t.TokenType,
+		RefreshToken: t.RefreshToken,
+		Expiry:       t.Expiry,
+		ExpiresIn:    t.ExpiresIn,
+		raw:          t.Raw,
+	}
+}
+
+// retrieveToken takes a *Config and uses that to retrieve an *internal.Token.
+// This token is then mapped from *internal.Token into an *oauth2.Token which is returned along
+// with an error.
+func retrieveToken(ctx context.Context, c *Config, v url.Values) (*Token, error) {
+	tk, err := internal.RetrieveToken(ctx, c.ClientID, c.ClientSecret, c.Endpoint.TokenURL, v, internal.AuthStyle(c.Endpoint.AuthStyle), c.authStyleCache.Get())
+	if err != nil {
+		if rErr, ok := err.(*internal.RetrieveError); ok {
+			return nil, (*RetrieveError)(rErr)
+		}
+		return nil, err
+	}
+	return tokenFromInternal(tk), nil
+}
+
+// RetrieveError is the error returned when the token endpoint returns a
+// non-2XX HTTP status code or populates RFC 6749's 'error' parameter.
+// https://datatracker.ietf.org/doc/html/rfc6749#section-5.2
+type RetrieveError struct {
+	Response *http.Response
+	// Body is the body that was consumed by reading Response.Body.
+	// It may be truncated.
+	Body []byte
+	// ErrorCode is RFC 6749's 'error' parameter.
+	ErrorCode string
+	// ErrorDescription is RFC 6749's 'error_description' parameter.
+	ErrorDescription string
+	// ErrorURI is RFC 6749's 'error_uri' parameter.
+	ErrorURI string
+}
+
+func (r *RetrieveError) Error() string {
+	if r.ErrorCode != "" {
+		s := fmt.Sprintf("oauth2: %q", r.ErrorCode)
+		if r.ErrorDescription != "" {
+			s += fmt.Sprintf(" %q", r.ErrorDescription)
+		}
+		if r.ErrorURI != "" {
+			s += fmt.Sprintf(" %q", r.ErrorURI)
+		}
+		return s
+	}
+	return fmt.Sprintf("oauth2: cannot fetch token: %v\nResponse: %s", r.Response.Status, r.Body)
+}
diff --git a/vendor/golang.org/x/oauth2/transport.go b/vendor/golang.org/x/oauth2/transport.go
new file mode 100644
index 0000000..8bbebba
--- /dev/null
+++ b/vendor/golang.org/x/oauth2/transport.go
@@ -0,0 +1,75 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package oauth2
+
+import (
+	"errors"
+	"log"
+	"net/http"
+	"sync"
+)
+
+// Transport is an [http.RoundTripper] that makes OAuth 2.0 HTTP requests,
+// wrapping a base [http.RoundTripper] and adding an Authorization header
+// with a token from the supplied [TokenSource].
+//
+// Transport is a low-level mechanism. Most code will use the
+// higher-level [Config.Client] method instead.
+type Transport struct {
+	// Source supplies the token to add to outgoing requests'
+	// Authorization headers.
+	Source TokenSource
+
+	// Base is the base RoundTripper used to make HTTP requests.
+	// If nil, http.DefaultTransport is used.
+	Base http.RoundTripper
+}
+
+// RoundTrip authorizes and authenticates the request with an
+// access token from Transport's Source.
+func (t *Transport) RoundTrip(req *http.Request) (*http.Response, error) {
+	reqBodyClosed := false
+	if req.Body != nil {
+		defer func() {
+			if !reqBodyClosed {
+				req.Body.Close()
+			}
+		}()
+	}
+
+	if t.Source == nil {
+		return nil, errors.New("oauth2: Transport's Source is nil")
+	}
+	token, err := t.Source.Token()
+	if err != nil {
+		return nil, err
+	}
+
+	req2 := req.Clone(req.Context())
+	token.SetAuthHeader(req2)
+
+	// req.Body is assumed to be closed by the base RoundTripper.
+	reqBodyClosed = true
+	return t.base().RoundTrip(req2)
+}
+
+var cancelOnce sync.Once
+
+// CancelRequest does nothing. It used to be a legacy cancellation mechanism
+// but now only it only logs on first use to warn that it's deprecated.
+//
+// Deprecated: use contexts for cancellation instead.
+func (t *Transport) CancelRequest(req *http.Request) {
+	cancelOnce.Do(func() {
+		log.Printf("deprecated: golang.org/x/oauth2: Transport.CancelRequest no longer does anything; use contexts")
+	})
+}
+
+func (t *Transport) base() http.RoundTripper {
+	if t.Base != nil {
+		return t.Base
+	}
+	return http.DefaultTransport
+}