Merge pull request #669 from onflow/janez/flow-block-height

Add debug_flowHeight API endpoint

Author: janezpodhostnik

README.md

@@ -267,6 +267,8 @@ The EVM Gateway implements APIs according to the Ethereum specification: https:/
     * debug_traceBlockByNumber
     * debug_traceBlockByHash
 
+- debug_flowHeightByBlock - returns the flow block height for the given EVM block (id or height)
+
 **Unsupported APIs**
 - Wallet APIs: we don't officially support wallet APIs (eth_accounts, eth_sign, eth_signTransaction, eth_sendTransaction) due to security
   concerns that come with managing the keys on production environments, however, it is possible to configure the gateway to allow these

api/api.go

@@ -76,6 +76,7 @@ var validMethods = map[string]struct{}{
 	"debug_traceBlockByNumber": {},
 	"debug_traceBlockByHash":   {},
 	"debug_traceCall":          {},
+	"debug_flowHeightByBlock":  {},
 
 	// web3 namespace
 	"web3_clientVersion": {},

api/debug.go

@@ -361,6 +361,25 @@ func (d *DebugAPI) TraceCall(
 	return tracer.GetResult()
 }
 
+// FlowHeightByBlock returns the Flow height for the given EVM block specified either by EVM
+// block height or EVM block hash.
+func (d *DebugAPI) FlowHeightByBlock(
+	_ context.Context,
+	blockNrOrHash rpc.BlockNumberOrHash,
+) (uint64, error) {
+	height, err := resolveBlockTag(&blockNrOrHash, d.blocks, d.logger)
+	if err != nil {
+		return 0, err
+	}
+
+	cdcHeight, err := d.blocks.GetCadenceHeight(height)
+	if err != nil {
+		return 0, err
+	}
+
+	return cdcHeight, nil
+}
+
 func (d *DebugAPI) executorAtBlock(block *models.Block) (*evm.BlockExecutor, error) {
 	snapshot, err := d.registerStore.GetSnapshotAt(block.Height)
 	if err != nil {

tests/e2e_web3js_test.go

@@ -36,6 +36,10 @@ func TestWeb3_E2E(t *testing.T) {
 		runWeb3Test(t, "debug_traces_test")
 	})
 
+	t.Run("test debug utils", func(t *testing.T) {
+		runWeb3Test(t, "debug_util_test")
+	})
+
 	t.Run("test setup sanity check", func(t *testing.T) {
 		runWeb3Test(t, "setup_test")
 	})

tests/web3js/debug_util_test.js

@@ -0,0 +1,15 @@
+const { assert } = require('chai')
+const helpers = require('./helpers')
+const conf = require('./config')
+
+it('should retrieve flow height', async () => {
+    let response = await helpers.callRPCMethod(
+        'debug_flowHeightByBlock',
+        ['latest']
+    )
+    assert.equal(response.status, 200)
+    assert.isDefined(response.body)
+
+    let height = response.body.result
+    assert.equal(height, conf.startBlockHeight)
+})