How to delete assets/participants using REST API on Hyperledger Composer? - hyperledger

Question

I have deployed my business network using composer-rest-server and am able to call the API using postman.
For now I have hard coded ID's for participants/assets, so I cannot make another POST call as objects with the ID already exist.
Where can I delete the existing participants/assets? On composer playground there was a delete button on the testing page that provided this functionality.

Answer 1

If you are using POSTMAN, you can use the DELETE request to remove your test data.
Using the Trade sample from the Composer tutorials, you would use the following curl command to remove the Commodity COAL:
curl -X DELETE --header 'Accept: application/json' 'http://localhost:3000/api/Commodity/COAL'
If you want to remove all the data in you Business Network, you could investigate the composer network reset command. (described here in the Composer docs.)

Answer 2

using javascript composer-client you can do the following:
const { BusinessNetworkConnection } = require('composer-client');
const participantRegistry = await BusinessNetworkConnection.getParticipantRegistry(registry name space, type);
await participantRegistry.remove(registry name space#participantId);
const assetRegistry = await BusinessNetworkConnection.getAssetRegistry(registry name space);
await assetRegistry.remove(registry name space#asset id);
or even you can perform more
await assetRegistry.removeAll(registry name space);
however before deleting participant from registry you should revoke the bounded identity to it by doing the following:
const IdentityRevoke = require('composer-cli').Identity.Revoke;
let options = {
card: 'admin#tutorial-network',
identityId: 'f1c5b9fe136d7f2d31b927e0dcb745499aa039b201f83fe34e243f36e1984862'
};
IdentityRevoke.handler(options);
you can find more information in the documentation about revoking identity in the following link

Answer 3

Since you have deployed the API, use its Swagger interface to look at what you can do. It is a RESTful api which means each endpoint accepts the HTTP verbs that make sense for it.
Each asset and participant endpoint, for example, accepts DELETE requests where all you have to do is pass the ID of the entity you want to delete.
You can issue POST requests to create new data and PUT requests to update the data.
One thing to be aware of is that each request will create a new block on the ledger. DELETE doesn't mean the previous block disappears, it simply means it's in a deleted state and your block count keeps increasing for each transaction you issue.
If you want to run tests and make sure your assets get created properly then you can start using the feature files, there is a sample feature to get you started. It uses a specific composer cucumber package, you can see that if you look inside the package.json. This would be the preferred method to run tests, as this isn't a normal environment where you create test data and then delete it, you have to be careful as your block count will keep increasing.