Your app displays the sign-in page

When the user goes to the sign-in page and the app loads for the first time, create an SDK Client object by calling NewClient.

idx, err := idx.NewClient(
      c.Okta.IDX.ClientID,
      c.Okta.IDX.ClientSecret,
      c.Okta.IDX.Issuer,
      c.Okta.IDX.Scopes,
      c.Okta.IDX.RedirectURI)
if err != nil {
    log.Fatalf("new client error: %+v", err)
}

Display a sign-in page that captures the user's name and password.

During page load, call Client.InitLogin. This returns a LoginResponse object that is used to initiate the sign-in process with Okta.

lr, err := s.idxClient.InitLogin(context.TODO())
if err != nil {
    log.Fatalf("Could not initalize login: %s", err.Error())
}

The user submits their username and password

When the user submits their username and password, create an IdentityRequest object and assign its identifier and password properties to the values entered by the user. Pass this object as a parameter to LoginResponse.Identify.

ir := &idx.IdentifyRequest{
    Identifier: r.FormValue("identifier"),
    Credentials: idx.Credentials{
        Password: r.FormValue("password"),
    },
}

lr, err = lr.Identify(context.TODO(), ir)
if err != nil {
    session.Values["Errors"] = err.Error()
    session.Save(r, w)
    http.Redirect(w, r, "/login", http.StatusFound)
    return
}

Your app handles an authentication success response

When the user correctly supplies their password, err is nil and LoginResponse.Token contains the required access and ID tokens to retrieve the user's OIDC claims information. The user is now signed in.

 //If we have tokens we have success, so lets store tokens
if lr.Token() != nil {
  session, err := sessionStore.Get(r, "direct-auth")
  if err != nil {
    log.Fatalf("could not get store: %s", err)
  }
  session.Values["access_token"] = lr.Token().AccessToken
  session.Values["id_token"] = lr.Token().IDToken

  err = session.Save(r, w)
  if err != nil {
    log.Fatalf("could not save access token: %s", err)
  }
 //Redirect the user to /profile
  http.Redirect(w, r, "/", http.StatusFound)
  return
}

Store these tokens for future requests and redirect the user to the default page after a successful sign-in attempt.