Raise EthersError when JSON-RPC fails

ethers/providers/jsonrpc.nim

@@ -2,6 +2,7 @@ import std/json
 import std/tables
 import std/uri
 import pkg/json_rpc/rpcclient
+import pkg/json_rpc/errors
 import ../basics
 import ../provider
 import ../signer
@@ -30,6 +31,12 @@ type
 template raiseProviderError(message: string) =
   raise newException(JsonRpcProviderError, message)
 
+template convertError(body) =
+  try:
+    body
+  except JsonRpcError as error:
+    raiseProviderError(error.msg)
+
 # Provider
 
 const defaultUrl = "http://localhost:8545"
@@ -77,10 +84,12 @@ proc new*(_: type JsonRpcProvider, url=defaultUrl): JsonRpcProvider =
 proc send*(provider: JsonRpcProvider,
            call: string,
            arguments: seq[JsonNode] = @[]): Future[JsonNode] {.async.} =
+  convertError:
     let client = await provider.client
     return await client.call(call, %arguments)
 
 proc listAccounts*(provider: JsonRpcProvider): Future[seq[Address]] {.async.} =
+  convertError:
     let client = await provider.client
     return await client.eth_accounts()
 
@@ -91,21 +100,25 @@ proc getSigner*(provider: JsonRpcProvider, address: Address): JsonRpcSigner =
   JsonRpcSigner(provider: provider, address: some address)
 
 method getBlockNumber*(provider: JsonRpcProvider): Future[UInt256] {.async.} =
+  convertError:
     let client = await provider.client
     return await client.eth_blockNumber()
 
 method getBlock*(provider: JsonRpcProvider,
                  tag: BlockTag): Future[?Block] {.async.} =
+  convertError:
     let client = await provider.client
     return await client.eth_getBlockByNumber(tag, false)
 
 method call*(provider: JsonRpcProvider,
              tx: Transaction,
              blockTag = BlockTag.latest): Future[seq[byte]] {.async.} =
+  convertError:
     let client = await provider.client
     return await client.eth_call(tx, blockTag)
 
 method getGasPrice*(provider: JsonRpcProvider): Future[UInt256] {.async.} =
+  convertError:
     let client = await provider.client
     return await client.eth_gasprice()
 
@@ -113,21 +126,25 @@ method getTransactionCount*(provider: JsonRpcProvider,
                             address: Address,
                             blockTag = BlockTag.latest):
                            Future[UInt256] {.async.} =
+  convertError:
     let client = await provider.client
     return await client.eth_getTransactionCount(address, blockTag)
 
 method getTransactionReceipt*(provider: JsonRpcProvider,
                             txHash: TransactionHash):
                            Future[?TransactionReceipt] {.async.} =
+  convertError:
     let client = await provider.client
     return await client.eth_getTransactionReceipt(txHash)
 
 method estimateGas*(provider: JsonRpcProvider,
                     transaction: Transaction): Future[UInt256] {.async.} =
+  convertError:
     let client = await provider.client
     return await client.eth_estimateGas(transaction)
 
 method getChainId*(provider: JsonRpcProvider): Future[UInt256] {.async.} =
+  convertError:
     let client = await provider.client
     try:
       return await client.eth_chainId()
@@ -138,6 +155,7 @@ proc subscribe(provider: JsonRpcProvider,
                name: string,
                filter: ?Filter,
                handler: SubscriptionHandler): Future[Subscription] {.async.} =
+  convertError:
     let client = await provider.client
     doAssert client of RpcWebSocketClient, "subscriptions require websockets"
 
@@ -164,6 +182,7 @@ method subscribe*(provider: JsonRpcProvider,
   return await provider.subscribe("newHeads", Filter.none, handler)
 
 method unsubscribe*(subscription: JsonRpcSubscription) {.async.} =
+  convertError:
     let provider = subscription.provider
     provider.subscriptions.del(subscription.id)
     let client = await provider.client
@@ -186,12 +205,14 @@ method getAddress*(signer: JsonRpcSigner): Future[Address] {.async.} =
 
 method signMessage*(signer: JsonRpcSigner,
                     message: seq[byte]): Future[seq[byte]] {.async.} =
+  convertError:
     let client = await signer.provider.client
     let address = await signer.getAddress()
     return await client.eth_sign(address, message)
 
 method sendTransaction*(signer: JsonRpcSigner,
                         transaction: Transaction): Future[TransactionResponse] {.async.} =
+  convertError:
     let
       client = await signer.provider.client
       hash = await client.eth_sendTransaction(transaction)

testmodule/testJsonRpcProvider.nim

@@ -241,3 +241,17 @@ suite "JsonRpcProvider":
     wantedConfirms = int.high
     check receipt.hasBeenMined(currentBlock, wantedConfirms)
 
+  test "raises JsonRpcProviderError when something goes wrong":
+    let provider = JsonRpcProvider.new("http://invalid.")
+    expect JsonRpcProviderError:
+      discard await provider.listAccounts()
+    expect JsonRpcProviderError:
+      discard await provider.send("evm_mine")
+    expect JsonRpcProviderError:
+      discard await provider.getBlockNumber()
+    expect JsonRpcProviderError:
+      discard await provider.getBlock(BlockTag.latest)
+    expect JsonRpcProviderError:
+      discard await provider.subscribe(proc(_: Block) {.async.} = discard)
+    expect JsonRpcProviderError:
+      discard await provider.getSigner().sendTransaction(Transaction.example)