Prerequisites for OAuth 2.0 authentication

1. Click "Create a project". Give the name of your project. An identifier is automatically proposed for your project.
2. Validate
3. The project is created.
4. In the menu on the left, click "API and authentication" then "API".
5. Choose the services required by the application:
   • To access the calendars, choose "Calendar API" ("Google Apps APIs" category).
   • To access the contacts, choose "Contacts API" ("Google Apps APIs" category).
   • To access the Google documents, choose "Drive API" ("Google Apps APIs" category).
   • To access the Picasa albums and the documents, there is no need to select a specific API.
6. In the menu on the left, click "Identifiers".
7. Then, click the "Create a client identifier" button.
   • Select the type of application: "Application installed".
   • The authorization screen must be configured during the first creation of client identifier.
   • In the authorisation screen, in the "Product name" area, enter the name of your application for example.
   • Click "Save".
   • The screen for creating the client identifier is re-displayed.
     • For WINDEV applications, select "Installed application", then "Other".
     • For the WEBDEV websites, select "Web application". In the "Authorized redirection URI" area, enter the address of the Web server where your site is installed followed by "/WD300AWP/WD300Awp.exe/GGLCONNECT_RETURN". The syntax has the following type:
       
       http[s]://<Nom_ou_IP_Serveur>[:<Port>]/WD300AWP/WD300AWP.exe/GGLCONNECT_RETOUR
       
       For example:
       • In test mode, with a Web server configured on the default port (80):
         
         http://localhost/WD300AWP/WD300AWP.exe/GGLCONNECT_RETOUR
       • In test mode, with a Web server configured on port 8080:
         
         http://localhost:8080/WD300AWP/WD300AWP.exe/GGLCONNECT_RETOUR
       • In Internet deployment, with a Web server configured on the default port with "www.mydomain.com" as domain:
         
         http://www.mondomaine.com/WD300AWP/WD300AWP.exe/GGLCONNECT_RETOUR
       • In Internet deployment, with a Web server configured in https on the default port (443) with "www.mydomain.com" as domain:
         
         https://www.mondomaine.com/WD300AWP/WD300AWP.exe/GGLCONNECT_RETOUR
       • In Intranet deployment, with a Web server configured on port 81 with "IntranetServer" as computer name:
         
         http://ServeurIntranet:81/WD300AWP/WD300AWP.exe/GGLCONNECT_RETOUR
   • Validate. The client identifiers are created:
     • Client identifier. This identifier must be stored. It will be used in the gglConnection variable.
     • Client secret code. This identifier must be stored. It will be used in the gglConnection variable.
     • Redirection URI. Check whether "http://localhost" is specified.

OAuth 2.0 authentication

1. The opening of a login window for the end user. If the Email property of the gglConnection variable is specified, Google pre-populates the connection window with the specified email address. The login window is not displayed if the user is already connected.
2. The opening of the authorisation window. The end user must allow the application to access his account. This window is automatically closed when the user accepts or cancels.

• If the syntax 1 is used (connection with basic authentication), an authorization window will be displayed whenever an attempt is performed to access a new service.
• If the syntax 2 is used (connection by specifying the services used), an authorization window will be displayed for all the services requested at the beginning of the application.
• The authorization window can be displayed during the first application start if the persistence of connection is managed (see next paragraph).

Limitations: The OAuth 2.0 authentication is not supported if the connection requires interactivity (validation of Google pages):

• In the web services.
• In Ajax.
• In the scheduled WEBDEV tasks.
• In the delayed WEBDEV tasks.
• In the threads.

In this case, we recommend that you use the persistence of connection.

Caution: The session timeout is also applied when displaying Google connection pages.

Connection persistence

let sFichierPersistanceAuth = SysDir(srLocalAppData) + [fSep] + "authggl.xml"

cnx is gglConnection 
// Si connexion déjà effectuée
IF fFileExist(sFichierPersistanceAuth) THEN 
	// Restauration de la connexion 
	let bufDésérialise = fLoadBuffer(sFichierPersistanceAuth) 
	Deserialize(cnx, bufDésérialise, psdXML) 
ELSE 
	// Nouvelle connexion 
	cnx.Email = "email@gmail.com" 
	cnx.ClientID = "387756281032-qffa6dajjd5348iqhi558xxxxxxxx.apps.googleusercontent.com" 
	cnx.ClientSecret = "Sxxxxx-jLMwwh" 
END 

IF cnx.Connected(gglServiceCalendar) THEN 
	// Sauvegarde de la connexion pour réutilisation future 
	bufSérialise is Buffer 
	Serialize(cnx, bufSérialise, psdXML) 
	fSaveBuffer(sFichierPersistanceAuth, bufSérialise) 
END