Method getUserIDByEmail

backend/plugin/webhook/teams/app.go:249–280

(ctx context.Context, email string)

}

func (p *provider) getUserIDByEmail(ctx context.Context, email string) (string, error) {
	// First, try to get user directly by userPrincipalName.
	apiURL := fmt.Sprintf("https://graph.microsoft.com/v1.0/users/%s", url.PathEscape(email))

	b, err := p.doGraphRequest(ctx, http.MethodGet, apiURL, nil)
	if err == nil {
		var user userResponse
		if err := json.Unmarshal(b, &user); err == nil && user.ID != "" {
			return user.ID, nil
		}
	}

	// If direct lookup fails, search by mail field (needed for guest users).
	// Guest users have UPNs like "user_domain.com#EXT#@tenant.onmicrosoft.com"
	// but their mail field contains the original email.
	filterURL := fmt.Sprintf("https://graph.microsoft.com/v1.0/users?$filter=mail%%20eq%%20'%s'", url.QueryEscape(email))
	b, err = p.doGraphRequest(ctx, http.MethodGet, filterURL, nil)
	if err != nil {
		return "", errors.Wrapf(err, "failed to search user by mail")
	}

	var users usersResponse
	if err := json.Unmarshal(b, &users); err != nil {
		return "", errors.Wrapf(err, "failed to unmarshal users response")
	}

	if len(users.Value) == 0 {
		return "", errors.Errorf("user with email %s not found", email)
	}

	return users.Value[0].ID, nil
}

// getTeamsAppID retrieves the Teams app ID from the app catalog.
// The app must be published to the organization's app catalog.