Getting a list of mobility service providers around a traveller’s pickup location (Java)
In this use case, the user searches for nearby mobility service providers around the traveller’s pickup location
Code snippets
Client calls the BAP server to trigger search:
@PostMapping("/mobility/search_by_pickup_location")
public ResponseEntity searchByPickupLocation(
@RequestHeader HttpHeaders headers,
@RequestBody ClientSearchRequest request) {
var response = bapApplicationService.generateSearchRequest(request, headers);
return ResponseEntity.ok(response);
}BAP server generates the protocol request body
/*
Example Request JSON:
{
"context": {
"domain": "nic2004:60221",
"country": "IND",
"city": "std:080",
"action": "search",
"core_version": "0.9.1",
"bap_id": "https://mock_bap.com/",
"bap_uri": "https://mock_bap.com/beckn/",
"transaction_id": "1209849124",
"message_id": "12341242342",
"timestamp": "2021-03-23T10:00:40.065Z"
},
"message": {
"intent" : {
"fulfillment": {
"start" : {
"location" : {
"gps" : "12.9349377,77.6055586"
}
}
}
}
}
}
*/
public Response generateSearchRequest(ClientSearchRequest request, HttpHeaders headers) {
var messageId = UUID.randomUUID().toString();
// Check and create transaction id if not passed
var txnId = StringUtils.hasText(request.getTransactionId())
? request.getTransactionId()
: UUID.randomUUID().toString();
// Construct the request similar to the example given above
var context = Context.builder().domain(request.getDomain())
.action(Context.ActionEnum.search)
.messageId(messageId)
.transactionId(txnId)
.transactionId(UUID.randomUUID().toString())
.timestamp(new Date().toString())
.build();
var intentBuilder = Intent.builder();
// Construct fulfilment object for the request from pickup location
intentBuilder = intentBuilder.fulfillment(ClientAssembler.of(request.getFulfilment()));
var searchRequest = SearchRequest.builder()
.context(context)
.message(SearchMessage.builder()
.intent(intentBuilder.build()).build()).build();
return invokeSearch(searchRequest, headers);
}
}BAP server calls protocol search to the network
public Response invokeSearch(SearchRequest request, HttpHeaders headers) {
// Call to look up function which returns the the public key and BPP/BG Endpoint to be called
var url = lookUp(headers);
//Call BPP Search api
var searchResponse = apiClient.post(url[0] + Context.ActionEnum.search,
constructRequestHeaders(),
request,
Response.class);
if (responseEntity.getBody() == null || responseEntity.getBody().getError() != null ||
"NACK".equals(responseEntity.getBody().getMessage().getAck().getStatus())) {
// Return custom error to the client
return null;
}
return searchResponse.getBody();
}BAP receives protocol on_search
/*
Example Response JSON:
{
"context": {
"domain": "nic2004:60221",
"country": "IND",
"city": "std:080",
"action": "on_search",
"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": "12341242343",
"timestamp": "2021-03-23T10:00:40.065Z"
},
"message": {
"catalog": {
"bpp/descriptor": {
"name": "Big Mobility"
},
"bpp/providers": [
{
"id": "yellow-mobility",
"descriptor" : {
"name": "Yellow Cabs"
},
"locations": [
{
"id": "closest-suv-spot",
"gps": "12.9349377,77.6055586"
},
{
"id": "closest-sedan-spot",
"gps": "12.9349377,77.6055586"
},
{
"id": "closest-sedan-outstation",
"gps": "12.9349377,77.6055586"
}
],
"categories": [
{
"id": "spot_booking",
"descriptor": {
"name": "Spot booking"
}
},
{
"id": "outstation",
"descriptor": {
"name": "Outstation"
}
}
],
"items": [
{
"id": "sedan_spot",
"descriptor" : {
"name" : "4 seater Sedan",
"images" : [
"https://mock_bpp.com/images/sedan.jpg"
]
},
"category_id": "spot_booking",
"location_id": "closest-sedan-spot",
"price" : {
"currency": "INR",
"value": "170"
},
"time": {
"label": "ETA",
"duration": "P14M"
},
"matched": true
},
{
"id": "suv_spot",
"descriptor" : {
"name" : "6 seater SUV ",
"images" : [
"https://mock_bpp.com/images/suv.jpg"
]
},
"category_id": "spot_booking",
"location_id": "closest-suv-spot",
"price" : {
"currency": "INR",
"value": "290"
},
"time": {
"label": "ETA",
"duration": "P12M"
},
"matched": true
},
{
"id": "sedan_outstation",
"descriptor" : {
"name" : "4 Seater Sedan",
"images" : [
"https://mock_bpp.com/images/sedan-out.jpg"
]
},
"category_id": "outstation",
"location_id": "closest-sedan-outstation",
"price" : {
"currency": "INR",
"value": "570"
},
"time": {
"label": "ETA",
"duration": "P17M"
},
"matched": true
}
]
},
{
"id": "red-mobility",
"descriptor": {
"name": "Cabs 4 All"
},
"locations": [
{
"id": "closest-sedan",
"gps": "12.9349377,77.6055586"
}
],
"categories": [
{
"id": "rental",
"descriptor": {
"name": "Rental"
}
}
],
"items": [
{
"id": "sedan_rental",
"descriptor" : {
"name" : "Sedan 5 hours",
"images" : [
"https://mock_bpp.com/images/sedan_rental.jpg"
]
},
"category_id": "rental",
"location_id": "closest-sedan",
"price" : {
"currency": "INR",
"value": "200"
},
"time": {
"label": "ETA",
"duration": "P12M"
},
"matched": true
}
]
}
]
}
}
}
*/
@PostMapping("/bap/on_search")
public ResponseEntity onSearch(
@RequestHeader HttpHeaders headers,
@RequestBody OnSearchRequest request) {
var response = bapCallbackApplicationService.onSearch(request, headers);
return ResponseEntity.ok(response);
}
public Response onSearch(OnSearchRequest request, HttpHeaders headers) {
// Validate the headers received
var isHeadersValid = validateHeaders(headers);
// Construct and return error if the received headers are invalid
if (!isHeadersValid) return null;
// Store the data received based on message id for the client to poll
saveToDB(request);
return Response.of("ACK", null);
}Client polls BAP to get the on_search results
// Endpoint for the client to poll the search data based on the message id
@GetMapping("/mobility/on_search")
public ResponseEntity searchByMessageId(
@PathVariable(ClientRoutes.PARAM_MESSAGE_ID) String messageId,
@RequestHeader HttpHeaders headers) {
var data = bapApplicationService.getSearchData(messageId);
return ResponseEntity.ok(data);
}