Confirming a mobility service that requires payment before confirmation and receiving a confirmed booking (Node.js)

In this use case, the user confirms a booking of a mobility service after making the payment and receives a confirmed booking

Code snippets

BPP receives protocol confirm

/*
Example Request JSON:
{
    "context": {
        "domain": "nic2004:60221",
        "country": "IND",
        "city": "std:080",
        "action": "confirm",
        "core_version": "0.9.1",
        "bap_id": "https://mock_bap.com/",
        "bap_uri": "https://mock_bap.com/beckn/",
        "bpp_id": "https://mock_bpp.com/",
        "bpp_uri": "https://mock_bpp.com/beckn/",
        "transaction_id": "1209849124",
        "message_id": "12341242345",
        "timestamp": "2021-03-23T10:00:40.065Z"
    },
    "message": {
        "order": {
            "items":[
                {
                    "id": "sedan_spot",
                    "quantity": {
                        "count": 1
                    }
                },
            ],
            "billing": {
                "name": "John Doe",
                "address": {
                    "door": "21A",
                    "name": "ABC Apartments",
                    "locality": "HSR Layout",
                    "city": "Bengaluru",
                    "state": "Karnataka",
                    "country": "India",
                    "area_code": "560102"
                },
                "email": "[email protected]",
                "phone": "+919876543210"
            },
            "fulfillment": {
                "tracking": true,
                "start": {
                    "location": {
                        "id": "user-location",
                        "descriptor": {
                            "name": "Current user location"
                        },
                        "gps": "12.9349377,77.6055586"
                    },
                    "instructions": {
                        "name": "pick up instructions",
                        "short_desc": "Ask doorman to ring 21A"
                    },
                    "time": {
                        "label": "ETA",
                        "duration": "P12M"
                    },
                    "contact": {
                        "phone": "+919999999999",
                        "email": "[email protected]"
                    }
                },
                "end": {
                    "location": {
                        "gps": "12.914028, 77.638698"
                    }
                }
            },
            "quote": {
                "price": {
                    "currency": "INR",
                    "value": "180"
                },
                "breakup": [
                    {
                        "title": "Sedan Spot Booking",
                        "price": {
                            "currency": "INR",
                            "value": "170"
                        }
                    },
                    {
                        "title": "Service Charge",
                        "price": {
                            "currency": "INR",
                            "value": "10"
                        }
                    }
                ]
            },
            "payment": {
                "uri": "https://api.bpp.com/pay?amt=$640&mode=upi&vpa=bpp@upi",
                "tl_method": "http/get",
                "params": {
                    "amount": "180",
                    "mode": "upi",
                    "vpa": "bpp@upi"
                },
                "type": "ON-ORDER",
                "status": "PAID"
            }
        }
    }
}
*/
    // Auth middleware authenticates the digital signature of the incoming request
    router.post('/mobility/confirm', auth, confirm);

    function confirm({ body }, res) {
        try {
            const message = _.get(body, "message");
            const context = _.get(body, "context");
            if (!context) {
                return res.status(400).send(httpResponse("NACK", "Missing Context"));
            }
            if (!message) {
                return res.status(400).send(httpResponse("NACK", "Missing Message"));
            }
            // ... Returns the ack immediately and continue the processing after validation
            res.status(200).send(httpResponse("ACK"));
            processConfirm(headers, body)
        } catch (error) {
            res.status(500).send(httpResponse("NACK", error));
        }
    };

BPP processes the confirm

    function processConfirm(requestHeaders, confirmRequestBody) {
        // Execute business logic here
        let confirmResponse = {}
        generateResponse(requestHeaders, confirmResponse)
    }

BPP generates response

    async function generateResponse(requestHeaders, rawResponse) {
/*
Example Request JSON :
{
    "context": {
        "domain": "nic2004:60221",
        "country": "IND",
        "city": "std:080",
        "action": "on_confirm",
        "core_version": "0.9.1",
        "bap_id": "https://mock_bap.com/",
        "bap_uri": "https://mock_bap.com/beckn/",
        "bpp_id": "https://mock_bpp.com/",
        "bpp_uri": "https://mock_bpp.com/beckn/",
        "transaction_id": "1209849124",
        "message_id": "12341242345",
        "timestamp": "2021-03-23T10:00:40.065Z"
    },
    "message": {
        "order": {
            "id":"trip_1",
            "state":"Driver en route",
            "items":[
                {
                    "id": "sedan_spot",
                    "quantity": {
                        "count": 1
                    }
                }
            ],
            "billing": {
                "name": "John Doe",
                "address": {
                    "door": "21A",
                    "name": "ABC Apartments",
                    "locality": "HSR Layout",
                    "city": "Bengaluru",
                    "state": "Karnataka",
                    "country": "India",
                    "area_code": "560102"
                },
                "email": "[email protected]",
                "phone": "+919876543210"
            },
            "fulfillment": {
                "tracking": true,
                "start": {
                    "location": {
                        "id": "user-location",
                        "descriptor": {
                            "name": "Current user location"
                        },
                        "gps": "12.9349377,77.6055586"
                    },
                    "instructions": {
                        "name": "pick up instructions",
                        "short_desc": "Ask doorman to ring 21A"
                    },
                    "time": {
                        "label": "ETA",
                        "duration": "P12M"
                    },
                    "contact": {
                        "phone": "+919999999999",
                        "email": "[email protected]"
                    }
                },
                "end": {
                    "location": {
                        "gps": "12.914028, 77.638698"
                    }
                }
            },
            "quote": {
                "price": {
                    "currency": "INR",
                    "value": "180"
                },
                "breakup": [
                    {
                        "title": "Sedan Spot Booking",
                        "price": {
                            "currency": "INR",
                            "value": "170"
                        }
                    },
                    {
                        "title": "Service Charge",
                        "price": {
                            "currency": "INR",
                            "value": "10"
                        }
                    }
                ]
            },
            "payment": {
                "uri": "https://api.bpp.com/pay?amt=$180&mode=upi&vpa=bpp@upi",
                "tl_method": "http/get",
                "params": {
                    "amount": "180",
                    "mode": "upi",
                    "vpa": "bpp@upi"
                },
                "type": "ON-ORDER",
                "status": "PAID"
            }
        }
    }
}
*/
        let onConfirmResponseBody = { }
        //call protocol on_confirm
        await callOnConfirm(requestHeaders, onConfirmResponseBody);
    }

BPP calls protocol on_confirm

    async function callOnConfirm(requestHeaders, onConfirmResponseBody) {
        // Take the subscriber Id from the header and calls the registry to get the url. If already cached it need not to call again
        const uri = await lookup(requestHeaders);
        // Construct Header
        const headers = constructAuthHeader(); // Auth Header with digital Signature
        return axios({ url: `${uri}/mobility/on_confirm`, method: "POST", data: onConfirmResponseBody });
    }