[E2E] Tests: API server (register, balance, transfer)

[sadiq1971]

Context

First batch of E2E tests covering the api-server: user registration (EIP-191), token balance queries, and EVM-style transfers between Canton parties.

Files to Create

All in tests/e2e/tests/api/, all with //go:build e2e.

main_test.go

//go:build e2e

package api_test

import (
    "os"
    "testing"

    "github.com/chainsafe/canton-middleware/tests/e2e/devstack/presets"
)

func TestMain(m *testing.M) {
    os.Exit(presets.DoMain(m))
}

register_test.go

Test	Scenario
TestRegister_NewUser_Success	Whitelist address, sign EIP-191 message, POST /register, assert 200 + canton_party_id non-empty
TestRegister_Duplicate_Idempotent	Register same address twice, assert both return same canton_party_id
TestRegister_NotWhitelisted_Fails	POST /register without whitelisting first, assert 4xx

balance_test.go

Test	Scenario
TestGetBalance_UnregisteredUser_ReturnsZero	eth_call balanceOf on unregistered address, expect "0"
TestGetBalance_AfterMintDEMO	DSL.MintDEMO then DSL.WaitForCantonBalance, verify balance matches
TestGetTokenMetadata	eth_call name/symbol/decimals on PROMPT token, verify non-empty responses

transfer_test.go

Test	Scenario
TestTransfer_DEMO_BetweenUsers	Register two users, mint DEMO to User1, transfer to User2, verify both balances
TestTransfer_InsufficientBalance_Fails	Attempt transfer of more than balance, expect error response
TestTransfer_PROMPT_AfterDeposit	Deposit PROMPT via bridge, wait for Canton balance, transfer to User2

Makefile update

test-e2e-api:
	go test -v -tags e2e -timeout 10m ./tests/e2e/tests/api/...

Acceptance Criteria

• make test-e2e-api passes green against a running stack.
• Each test is independent: uses t.Helper() + require.* (not assert.*) for fast failure.
• No test hard-codes addresses or ports — all resolved through sys.Manifest or DSL methods.

Dependencies

• Issue [E2E] Devstack: Layers 4/5/6 (System + DSL + Presets) #181 ([E2E] Devstack: Layers 4/5/6) — presets.DoMain, presets.NewAPIStack, sys.DSL.*.

Size

M (1 day)

[sadiq1971]

Depends on: #181