func()

in jira/jira.go [80:143]

• 54 lines of code
• 9 McCabe index (conditional complexity)

func (js jwtSource) Token() (*oauth2.Token, error) {
	exp := time.Duration(59) * time.Second
	claimSet := &ClaimSet{
		Issuer:       fmt.Sprintf("urn:atlassian:connect:clientid:%s", js.conf.ClientID),
		Subject:      fmt.Sprintf("urn:atlassian:connect:useraccountid:%s", js.conf.Subject),
		InstalledURL: js.conf.BaseURL,
		AuthURL:      js.conf.Endpoint.AuthURL,
		IssuedAt:     time.Now().Unix(),
		ExpiresIn:    time.Now().Add(exp).Unix(),
	}

	v := url.Values{}
	v.Set("grant_type", defaultGrantType)

	// Add scopes if they exist;  If not, it defaults to app scopes
	if scopes := js.conf.Scopes; scopes != nil {
		upperScopes := make([]string, len(scopes))
		for i, k := range scopes {
			upperScopes[i] = strings.ToUpper(k)
		}
		v.Set("scope", strings.Join(upperScopes, "+"))
	}

	// Sign claims for assertion
	assertion, err := sign(js.conf.ClientSecret, claimSet)
	if err != nil {
		return nil, err
	}
	v.Set("assertion", string(assertion))

	// Fetch access token from auth server
	hc := oauth2.NewClient(js.ctx, nil)
	resp, err := hc.PostForm(js.conf.Endpoint.TokenURL, v)
	if err != nil {
		return nil, fmt.Errorf("oauth2: cannot fetch token: %v", err)
	}
	defer resp.Body.Close()
	body, err := ioutil.ReadAll(io.LimitReader(resp.Body, 1<<20))
	if err != nil {
		return nil, fmt.Errorf("oauth2: cannot fetch token: %v", err)
	}
	if c := resp.StatusCode; c < 200 || c > 299 {
		return nil, fmt.Errorf("oauth2: cannot fetch token: %v\nResponse: %s", resp.Status, body)
	}

	// tokenRes is the JSON response body.
	var tokenRes struct {
		AccessToken string `json:"access_token"`
		TokenType   string `json:"token_type"`
		ExpiresIn   int64  `json:"expires_in"` // relative seconds from now
	}
	if err := json.Unmarshal(body, &tokenRes); err != nil {
		return nil, fmt.Errorf("oauth2: cannot fetch token: %v", err)
	}
	token := &oauth2.Token{
		AccessToken: tokenRes.AccessToken,
		TokenType:   tokenRes.TokenType,
	}

	if secs := tokenRes.ExpiresIn; secs > 0 {
		token.Expiry = time.Now().Add(time.Duration(secs) * time.Second)
	}
	return token, nil
}