How to response with a success JSON format after completing a transaction in corda - corda

Question

Hi everyone i am working on a project in which i need to send a response in JSON format to the CLI that the Transaction have completed let me give you an example.Consider that i have stated a flow Start ExampleFlow pojo: {iouValue: 7}, otherParty: "O=PartyB,L=London,C=GB" and the result will be Starting
Generating transaction based on new IOU.
Verifying contract constraints.
Signing transaction with our private key.
Gathering the counter party's signature.
Collecting signatures from counterparties.
Verifying collected signatures.
Obtaining notary signature and recording transaction.
Broadcasting transaction to participants
Done
Flow completed with result: SignedTransaction(id=F95406D901209BA77396C1A4D375585C6E051414EE22BE441FC02E5AE147A050)
but what i want is that their should be a JSON format result not all of it but something like this
{response: success }
i just want some success response in JSON format
i am using IOU project
thanks

Answer 1

You can achieve that by establishing an RPC connection with your node; call the flow, then return the JSON object.
There are a couple of approaches that you can follow, and I recommend that you go through the samples repository https://github.com/corda/samples to explore them:
Create a webserver (SpringBoot application) that server REST API's that call your flows and return a JSON object: https://github.com/corda/samples/tree/release-V4/spring-webserver
Create a simple Java app that establishes an RPC connection with your node and serves as a client to call a certain method/flow: https://github.com/corda/samples/blob/release-V4/cordapp-example/clients/src/main/java/com/example/server/JavaClientRpc.java
If you follow the webserver sample, you can add a method to your controller that does something like:
#GetMapping(value = "/my-api", produces = MediaType.APPLICATION_JSON_VALUE)
private ResponseEntity<YourObject> getSomething() {
// Some code that calls your flow and returns YourObject.
return ResponseEntity.ok().body(YourObject);
}

Answer 2

so i got the answer what u need to do is add this dependency in client build.gradle
cordaCompile "net.corda:corda-jackson:$corda_release_version"
after that you just need to implement this code snip
String json = "";
try {
ObjectMapper mapper = JacksonSupport.createNonRpcMapper();
json = mapper.writeValueAsString(results);
} catch (JsonProcessingException e) {
e.printStackTrace();
}
return json;
result can be any datatype you want to convert to json