WhatsApp Client

The IWhatsApp interface is for working with a WhatsApp Connector to a companies' WhatsApp Business Account.

To create an IWhatsApp instance, the static Create() function needs to be called. Two existing ISocketProvider (TCP and TLS) as well as an IDns instance must be passed to Create(). These instances must not be deleted before releasing the IWhatsApp instance!

File information

Filecommon/interface/whatsapp.h

Classes IWhatsAppClient
UWhatsAppClient
IWhatsAppOnboarding
UWhatsAppOnboarding

Classes

IWhatsAppClient


    class IWhatsAppClient {
    public:
    static IWhatsAppClient * Create(class IIoMux * const iomux,
    class UWhatsAppClient * const user,
    class ISocketProvider * const tcpSocketProvider,
    class ISocketProvider * const tlsSocketProvider,
    class IInstanceLog * const log,
    class IDns * const dns,
    class ISocketContext const socketContext = nullptr
    );

    virtual ~IWhatsAppClient() {}
    virtual void Close() = 0;
    virtual void SetConfig(const char * token, const char * secret) = 0;
    virtual void SetWebhookToken(const char* webhookToken) = 0;
    virtual void SendMessage(UWhatsAppClient * context, json_io value, word base, const char * remoteNum, const char * type, const char * channel, const char * callback_info=0, const char * refersToID = 0) = 0;
    virtual void RequestMedia(UWhatsAppClient * context, const char* destination, const char* mediaID, const char* detailsType) = 0;
    virtual const char* GetVersion() = 0;
    };

Overview

This is the interface to establish a WhatsApp for Business connection. The interface is quite simple and straight forward to use.

Public functions

Create (static function)
This static function creates the IWhatsAppClient Instance. The returned instance must be released if no longer needed by using the C++ delete operator.

Parameters

class IIoMux * const iomuxThe IIoMux instance the IWhatsAppClient instance will be registered to.
class UWhatsAppClient * const userThe UWhatsAppClient instance that will receive the callbacks of IWhatsAppClient.
class IWebserverPlugin * const webserverinstance that can create a Webserver Plugin.
class ISocketProvider * const tcpSocketProviderA ISocketProvider instance that can create a TCP ISocket.
class ISocketProvider * const tlsSocketProviderA ISocketProvider instance that can create a TLS ISocket.
class IInstanceLog * const logThe IInstanceLog instance used for logging purposes.
class IDns * const dnsThe IDns instance used to resolve the server name if needed.
class ISocketContext * const socketContext dnsThe ISocketContext Socket context if needed

Return value

The IWhatsAppClient Instance created. It must be freed by the C++ operator delete, if no longer be used.

Remarks

Note that the two ISocketProvider instances as well as the IDns instance must not be freed before the IWhatsAppClient instance had been deleted.
Close
Closes the WhatsAppClient. Will usually be called from a corresponding app.

Callbacks

Once the close is completed, UWhatsAppClient::WhatsAppClientCloseComplete() will be called. The WhatsAppClient-Object can thus be deleted then.
SetConfig
Sets certain configurations that are necessary to send or receive messages to/from WhatsApp. The App-Secret can be found in the Meta-Appdashboard. It is necessary for accepting incoming messages.

Parameters

const char * tokenA token used for authentication with WhatsApp
const char * secretThe App-Secret from Meta
SetWebhookToken
Sets a token that will be used for validation at registering webhooks (like receiving incoming messages) from WhatsApp at onboarding or at changing webhooks.

Parameters

const char * webhookTokenA token used for validating webhook registration
SendMessage
Sends the given data to the (private) WhatsApp Messenger Account identified by the phone number. A message to a private Account will only be delivered if a message from that private Account had been received within 24 hours before. Template-Messages are an exception an can be sent without preceding initiation from the private Account. If the data could not be send right now, it will be cached and sent later. The context will be informed if the data had been finally send or any errors that occur instead.

Parameters

UWhatsAppClient * contextThe user to receive callbacks for the given message
json_io valuejson_io of the message
word baseThe jsons base
const char * remoteNumThe mobile number of the recipients Whatsapp-Account
const char * typeType of the message (text, reaction, location, media, contact)
const char *channelThe channel used for sending aka whatsapp phone_id
const char * callback_infoOptional: additional information for the callback as src from frontend sendSrc
const char *refersToIDOptional: Whatsapp-Message-ID of previous message that is referred to (if any)

Callbacks

After the data had been send, UWhatsAppClient::WhatsAppClientSendMessageResult() will be called.
div class="fnhead">RequestMedia
Fetches Media from WhatsApp and posts (via HTTP) it to the given destination URL.

Parameters

UWhatsAppClient * contextThe user to receive callbacks for the given message
const char* destinationDestination to post the media to
const char* mediaIDThe WhatsApp-MediaID of the requested media (the original post from WhatsApp informing about the media will contain this data)
const char * detailsTypeMime-Type of the requested media
GetVersion()
Retrieves the version of the WhatsApp cloud API implemented.
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UWhatsAppClient


    class UWhatsAppClient {
    public:
    virtual ~UWhatsAppClient() {};
    virtual void WhatsAppClientCloseComplete(IWhatsAppClient * const whatsappClient) = 0;
    virtual void WhatsAppClientSendMessageResult(IWhatsAppClient * const whatsappClient, whatsapp_error_t error, const char * callback_info = 0, const char * content = 0) = 0;
    virtual void WhatsAppClientRecvMessage(IWhatsAppClient* const whatsappClient, const char* msg, const char* tel, const char * channel, const char * type, const char * id, const char * refersToID = 0) = 0;
    virtual void WhatsAppClientRecvMedia(IWhatsAppClient* const whatsAppClient, const char* sender, const char* channel, const char* wamid, const char* mediaid, const char* mimeType) = 0;
    };

Overview

The UWhatsAppClient class is used to receive callbacks from an IWhatsAppClient instance. An application must subclass UWhatsAppClient, implement the functions that must be implemented and pass that class as user to IWhatsAppClient::Create(). The instance of that subclass must not be freed before the IWhatsAppClient instance assigned to. One UWhatsAppClient instance can be assigned to multiple IWhatsAppClient instances, because the calling IWhatsAppClient will be passed as parameter to the callback functions.

Public functions

WhatsAppClientCloseComplete
Will be called after calling IWhatsAppClient::Close(). After receiving that callback, the IWhatsAppClient-Object can be deleted.

Parameters

class IWhatsAppClient * const whatsappClientThe calling IWhatsAppClient instance
WhatsAppClientSendMessageResult
Will be called after calling IWhatsAppClient::SendMessage(). After receiving that callback, the IWhatsAppClient instance can be used to send data and receive reactions.

Parameters

class IWhatsAppClient * const whatsappClientThe calling IWhatsAppClient instance
whatsapp_error_t errorThe error status after sending.
const char * callback_infoOpitional: additional information for the callback as src from frontend sendSrc
const char * contentOptional: additional content as Whatsapp-message-id
WhatsAppClientRecvMessage
Passes an incoming message from whatsapp to a user who has subscribed for receiving Messages for the phone number (or all Messages).

Parameters

class IWhatsAppClient * const whatsappClientThe calling IWhatsAppClient instance
const char * msgThe received message
const char * telThe sending telephone number
const char * channelThe channel used for sending aka whatsapp phone_id
const char * typeThe type of the received message (may be "text|image|status|reaction|location|contact")
const char * idThe Whatsapp-Message-ID of the message (necessary to refer to the message later)
const char *refersToIDWhatsapp-Message-ID of previous message that is referred to (if any)
virtual void WhatsAppClientRecvMedia(IWhatsAppClient* const whatsAppClient, const char* sender, const char* channel, const char* wamid, const char* mediaid, const char* mimeType) = 0;
WhatsAppClientRecvMedia
Informs the using app about incoming media. For the app to receive the media, a request to fetch it via GET-Request to /client/getMedia with Parameter id=mediaid is required.

Parameters

class IWhatsAppClient * const whatsappClientThe calling IWhatsAppClient instance
const char * senderThe sending telephone number
const char * channelThe channel used for sending aka whatsapp phone_id
const char * wamidThe Whatsapp-Message-ID of the message (necessary to refer to the message later)
const char * mediaidThe id of the media (necessary to retrieve the actual data)
const char * mimeTypeThe mime-type of the media

IWhatsAppOnboarding


    class IWhatsAppOnboarding {
    public:
    static IWhatsAppClient * Create(class IIoMux * const iomux,
    class UWhatsAppOnboarding * const user,
    class ISocketProvider * const tcpSocketProvider,
    class ISocketProvider * const tlsSocketProvider,
    class IInstanceLog * const log,
    class IDns * const dns,
    class ISocketContext const socketContext = nullptr
    );

    virtual ~IWhatsAppOnboarding() {}
    virtual void Close() = 0;
    virtual void Onboard(UWhatsAppOnbaording * context, const char* src, const char* vrsion, const char* code, const char* webhookToken, const char* wabaID, const char* callbackUri, const char* phoneID, const char* phonePin) = 0;
    };

Overview

This is the interface to start all necessary actions to onboard a new customer, which means retrieving a token, registering all necessary webhooks and registering the main phone number. For onboarding, the WhatsAppClient needs be running too.

Public functions

Create (static function)
This static function creates the IWhatsAppOnboarding Instance. The returned instance must be released if no longer needed by using the C++ delete operator.

Parameters

class IIoMux * const iomuxThe IIoMux instance the IWhatsAppClient instance will be registered to.
class UWhatsAppClient * const userThe UWhatsAppClient instance that will receive the callbacks of IWhatsAppClient.
class IWebserverPlugin * const webserverinstance that can create a Webserver Plugin.
class ISocketProvider * const tcpSocketProviderA ISocketProvider instance that can create a TCP ISocket.
class ISocketProvider * const tlsSocketProviderA ISocketProvider instance that can create a TLS ISocket.
class IInstanceLog * const logThe IInstanceLog instance used for logging purposes.
class IDns * const dnsThe IDns instance used to resolve the server name if needed.
class ISocketContext * const socketContext dnsThe ISocketContext Socket context if needed

Return value

The IWhatsAppOnboarding Instance created. It must be freed by the C++ operator delete, if no longer be used.

Remarks

Note that the two ISocketProvider instances as well as the IDns instance must not be freed before the IWhatsAppClient instance had been deleted.
Close
Closes the WhatsAppOnboarding. Will usually be called from a corresponding app once the onboarding is complete.

Callbacks

Once the close is completed, UWhatsAppOnboarding::WhatsAppOnboardingCloseComplete() will be called. The WhatsAppOnboarding-Object can thus be deleted then.

UWhatsAppOnboarding


    class UWhatsAppOnboarding {
    public:

    virtual ~UWhatsAppOnboarding() {}
    virtual void WhatsAppOnboardingCloseComplete(IWhatsAppOnboarding * const onboarding) = 0;
    virtual void WhatsAppOnboardingOnboardResult(IWhatsAppOnbaording * const onboarding, const char* callback_info, onboardingStatus status, const char* token = 0) = 0;
    };

Overview

This is the interface to start all necessary actions to onboard a new customer, which means retrieving a token, registering all necessary webhooks and registering the main phone number. For onboarding, the WhatsAppClient needs be running too.

Public functions

WhatsAppOnboardingCloseComplete
Callback from calling IWhatsAppOnboarding::Close(), signaling the Object stopped all current processes and is ready for deletion.
WhatsAppOnboardingOnboardResult
Callback from calling IWhatsAppOnboarding::Onboard(), providing the result of the onboarding.

Parameters

class IWhatsAppOnboarding * const onboardingThe onboarding instance that executed the onboarding.
const char * callback_infoInformation containing the src from the call, allowing to transmit the result back to frontend
onboardingStatus statusThe status of the onboarding. If completely successfull, the status is FINISHED. Otherwise it shows the last stage of the onboarding that was executed and failed.
const char* tokenIn case of success with at least the first stage (retrieving a token), the token is returned. The token is also saved to config and will be used for further authorization agains WhatsApp.

Data types

whatsapp_error_t


    typedef enum {
    WHATSAPP_ERR_OK = 0,
    WHATSAPP_ERR_MISSING_TOKEN,
    WHATSAPP_ERR_MISSING_VERSION,
    WHATSAPP_ERR_NOT_FOUND,
    WHATSAPP_ERR_BAD_REQUEST,
    WHATSAPP_ERR_AUTHENTICATION_FAILED,
    WHATSAPP_ERR_OTHER_HTTP,
    WHATSAPP_ERR_CLOSING
    } whatsapp_error_t;

This enum defines the possible outcomes for sending a message via the connector. One of them will be returned at UWhatsAppClient::WhatsAppClientSendMessageResult.

onboardingStatus


    typedef enum {
    UNSTARTED,
    FETCH_TOKEN,
    REGISTER_WEBHOOKS,
    REGISTER_PHONE,
    FINISHED
    } onboardingStatus;

This enum defines the possible outcomes for an onboarding. Stages are passed from Top to Bottom, signaling the failing stage if onboarding could not completely finished, allowing further follow-up for only the unfinished stages.

Getting the Data

The WhatsAppClient sends the data using the described methods to other Apps. The current App (Connector for WhatsApp) sends the data to Apps providing the Connect-API using methods of that API.

Code Example

IWhatsAppClient


    app::app(class IIoMux * iomux,
    ISocketProvider * tcpSocketProvider,
    ISocketProvider * tlsSocketProvider,
    IDns * dns,
    IInstanceLog * log)
    : iomux(iomux)
    {
        this->client = IWhatsAppClient::Create(iomux,
                                                this,
                                                webserverPlugin,
                                                tcpSocketProvider,
                                                tlsSocketProvider,
                                                this,
                                                dns);
    isTerminating = false;
    }

    void WhatsApp::Stop(){
    if (!isTerminating) {
        isTerminating = true;
        if (client != nullptr) client->Close();
        TryStop();
        }
    }

    void WhatsApp::TryStop(){
        if (isTerminating && client == nullptr) appService->AppStopped(this);
    }



    void app::WhatsAppClientCloseComplete(IWhatsAppClient* const whatsappClient){
        delete client;
        client = nullptr;
        TryStop();
    }

    void app::WhatsAppClientSendMessageResult(IWhatsAppClient* const whatsappClient, whatsapp_error_t error){
        //can ignore the result or act according to it
    }