Intro

Hooks supercharge the JAWCE engine. It makes it possible to hook custom additional functionality during message processing.

You want to send a Slack notification when user confirms their order? Add a hook.

How about to dynamically populate a message with some dynamic variables? .. yes .. hooks!

There a number of hooks that you can define in your template, the engine will do its best to handle the rest.

Here i will list some of the "hooks" and the other "fields" or "attributes" you can define in your templates

type - type of message to render
prop
on-receive
on-generate
validator
middleware
template
params
message
routes

You can probably guess what other hooks does by their name.

Hooks are segmented into POST or PRE hooks

Pre Hooks#

These are processed BEFORE the message is rendered and send to the user on WhatsApp.

In the order which they are processed

These includes

params
template
on-generate

Post Hooks#

These hooks are processed AFTER the user responds to a message.

In the order which they are processed

params
validator
on-receive
middleware
prop

REST API Hook Model

All REST API based hooks should accept a HookArgs model

Hook Model: HookArgs

public record WaCurrentUser(
        String name,        // display name
        String waId,        // mobile number
        String msgId,       // message id
        Long timestamp      // message timestamp
) {
}

public record TemplateDynamicBody(
        WebhookResponseMessageType type,        // for dynamic template message type
        Map<String, Object> payload,            // used for `flow` type - initial flow data
        Map<String, Object> renderPayload       // dynamic template data
) {
}

// main model
public class HookArgs {
    private WaCurrentUser channelUser;
    private String userInput;                           // user input from whatsapp
    private String flow;                                // flow name for flow template type
    private Map<String, Object> additionalData;
    private TemplateDynamicBody templateDynamicBody;
    private Map<String, Object> methodArgs;             // params to pass to hook if defined in template
}

class ChannelUser(BaseModel):
    name: str
    waId: str
    msgId: str
    timestamp: int

class TemplateDynamicBody(BaseModel):
    type: Union[str, None] = None
    payload: Union[dict, None] = None
    renderPayload: Union[dict, None] = None


# main model
class HookArgs(BaseModel):
    channelUser: ChannelUser
    userInput: Union[str, None] = None
    flow: Union[str, None] = None
    additionalData: Union[dict, None] = None
    templateDynamicBody: Union[TemplateDynamicBody, None] = None
    methodArgs: Union[dict, None] = None