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chore: extend types and readibility
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@mfw78
mfw78 committed Oct 7, 2023
1 parent 593719d commit 25ce427
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Showing 3 changed files with 84 additions and 81 deletions.
3 changes: 2 additions & 1 deletion package.json
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Original file line number Diff line number Diff line change
Expand Up @@ -14,7 +14,8 @@
"lint:fix": "eslint --fix \"src/**/*.ts\" && prettier --write \"src/**/*.ts\"",
"test": "yarn build && jest ./dist",
"typechain": "typechain --target ethers-v5 --out-dir src/types/generated/ \"abi/*.json\"",
"prepare": "husky install && yarn typechain"
"prepare": "husky install && yarn typechain",
"cli": "ts-node src/index.ts"
},
"devDependencies": {
"@commitlint/cli": "^17.6.7",
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14 changes: 8 additions & 6 deletions src/domain/checkForAndPlaceOrder.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -531,13 +531,13 @@ async function _pollLegacy(
},
]);

const [{ success, returnData: revertData }] = lowLevelCall;
const [{ success, returnData }] = lowLevelCall;

if (success) {
// Decode the result to get the order and signature
// Decode the returnData to get the order and signature tuple
const { order, signature } = contract.interface.decodeFunctionResult(
"getTradeableOrderWithSignature",
revertData
returnData
);
return {
result: PollResultCode.SUCCESS,
Expand All @@ -546,20 +546,22 @@ async function _pollLegacy(
};
}

// If the call failed, there may be a custom error to provide hints. Let's try.
// If the low-level call failed, per the `ComposableCoW` interface, the contract is attempting to
// provide hints to the watch-tower. But, we can't trust all the data returned as there may be
// order types created that are _not_ adhering to the interface (and are therefore invalid).
return handleOnChainCustomError({
owner,
orderRef,
chainId,
target,
callData,
revertData,
revertData: returnData,
});
} catch (error: any) {
log.error(`${logPrefix} ethers/call Unexpected error`, error);
// We can only get here from some provider / ethers failure. As the contract hasn't had it's say
// we will defer to try again.
// TODO: Add metrics to track this
log.error(`${logPrefix} ethers/call Unexpected error`, error);
return {
result: PollResultCode.TRY_NEXT_BLOCK,
reason:
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148 changes: 74 additions & 74 deletions src/utils/contracts.ts
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Original file line number Diff line number Diff line change
@@ -1,4 +1,4 @@
import { ethers } from "ethers";
import { BigNumber, ethers } from "ethers";
import { ComposableCoW, ComposableCoW__factory } from "../types";
import {
COMPOSABLE_COW_CONTRACT_ADDRESS,
Expand All @@ -15,7 +15,7 @@ const REQUIRED_SELECTORS = [
"getTradeableOrderWithSignature(address,(address,bytes32,bytes),bytes,bytes32[])",
];

// Define an enum for the custom errors that can be returned by the ComposableCoW contract
// Define an enum for the custom error revert hints that can be returned by the ComposableCoW's interfaces.
export enum CustomErrorSelectors {
PROOF_NOT_AUTHED = "PROOF_NOT_AUTHED",
SINGLE_ORDER_NOT_AUTHED = "SINGLE_ORDER_NOT_AUTHED",
Expand All @@ -30,6 +30,27 @@ export enum CustomErrorSelectors {
POLL_TRY_AT_EPOCH = "POLL_TRY_AT_EPOCH",
}

type ParsedCustomError = {
[K in CustomErrorSelectors]: K extends
| CustomErrorSelectors.PROOF_NOT_AUTHED
| CustomErrorSelectors.SINGLE_ORDER_NOT_AUTHED
| CustomErrorSelectors.INTERFACE_NOT_SUPPORTED
| CustomErrorSelectors.INVALID_FALLBACK_HANDLER
| CustomErrorSelectors.INVALID_HANDLER
| CustomErrorSelectors.SWAP_GUARD_RESTRICTED
? { selector: K }
: K extends
| CustomErrorSelectors.ORDER_NOT_VALID
| CustomErrorSelectors.POLL_TRY_NEXT_BLOCK
| CustomErrorSelectors.POLL_NEVER
? { selector: K; message: string }
: K extends
| CustomErrorSelectors.POLL_TRY_AT_BLOCK
| CustomErrorSelectors.POLL_TRY_AT_EPOCH
? { selector: K; message: string; blockNumberOrEpoch: number }
: never;
}[CustomErrorSelectors];

export const CUSTOM_ERROR_ABI_MAP: Record<CustomErrorSelectors, string> = {
[CustomErrorSelectors.PROOF_NOT_AUTHED]: "ProofNotAuthed()",
[CustomErrorSelectors.SINGLE_ORDER_NOT_AUTHED]: "SingleOrderNotAuthed()",
Expand Down Expand Up @@ -91,16 +112,14 @@ export function composableCowContract(
);
}

type ParsedCustomError = {
selector: CustomErrorSelectors;
message?: string;
blockNumberOrEpoch?: number;
};

/**
* Given a raw ABI-encoded custom error returned from a revert, extract the selector and optionally a message.
* Given a raw ABI-encoded custom error returned from a revert, extract the selector and any parameters.
* @param revertData ABI-encoded custom error, which may or may not be parameterized.
* @returns an empty parsed error if assumptions don't hold, otherwise the selector and message if applicable.
* @returns {ParsedCustomError} an object containing the selector and any parameters.
* @throws if the revert data is not at least 4 bytes long (8 hex characters, 0x prefixed), or if the
* revert data contains a selector that is not in the CUSTOM_ERROR_SELECTOR_MAP, or if the revert data
* contains a selector that is in the CUSTOM_ERROR_SELECTOR_MAP, but the it's parameters are not ABI-encoded
* correctly.
*/
export function parseCustomError(revertData: string): ParsedCustomError {
try {
Expand All @@ -119,6 +138,9 @@ export function parseCustomError(revertData: string): ParsedCustomError {
);
}

// Below here, the only throw that can happen is if the revert data contains a selector that is in the
// CUSTOM_ERROR_SELECTOR_MAP, but the it's parameters are not ABI-encoded correctly.

const selector = CUSTOM_ERROR_SELECTOR_MAP[rawSelector];
const fragment = ethers.utils.Fragment.fromString(
"error " + CUSTOM_ERROR_ABI_MAP[selector]
Expand Down Expand Up @@ -154,20 +176,19 @@ export function parseCustomError(revertData: string): ParsedCustomError {

return {
selector,
message: msg,
blockNumberOrEpoch: blockNumberOrEpoch.toNumber(),
message: msg as string,
blockNumberOrEpoch: (blockNumberOrEpoch as BigNumber).toNumber(),
};
}
} catch (err) {
// This can only throw under the following conditions:
// - The revert data is too short to contain a selector
// - The revert data contains a selector that is not in the CUSTOM_ERROR_SELECTOR_MAP
// - The revert data contains a selector that is in the CUSTOM_ERROR_SELECTOR_MAP, but the
// it's parameters are not ABI-encoded correctly (decode throws)
throw err;
}
}

/**
* Given a raw ABI-encoded custom error returned from a revert, determine subsequent polling actions.
* This function will swallow any errors thrown by `parseCustomError` and return a DONT_TRY_AGAIN result.
*/
export function handleOnChainCustomError(params: {
owner: string;
orderRef: string;
Expand All @@ -178,59 +199,52 @@ export function handleOnChainCustomError(params: {
}): PollResultErrors {
const { owner, orderRef, chainId, target, callData, revertData } = params;
const logPrefix = `contracts:handleOnChainCustomError:${orderRef}`;
const log = getLogger(logPrefix);

try {
// The below will throw if:
// - the error is not a custom error (ie. the selector is not in the map)
// - the error is a custom error, but the parameters are not as expected
const { selector, message, blockNumberOrEpoch } =
parseCustomError(revertData);
switch (selector) {
const parsedCustomError = parseCustomError(revertData);
const { selector } = parsedCustomError;
const log = getLogger(`${logPrefix}:${selector}`);
const msgWithSelector = (message: string): string =>
`${selector}: ${message}`;
const dropOrder = (reason: string): PollResultErrors => {
return {
result: PollResultCode.DONT_TRY_AGAIN,
reason: msgWithSelector(reason),
};
};
switch (parsedCustomError.selector) {
case CustomErrorSelectors.SINGLE_ORDER_NOT_AUTHED:
case CustomErrorSelectors.PROOF_NOT_AUTHED:
// If there's no authorization we delete the order
// - One reason could be, because the user CANCELLED the order
// - for now it doesn't support more advanced cases where the order is auth during a pre-interaction
log.info(
`${selector}: Order on safe ${owner} not authed. Deleting order...`
);
return {
result: PollResultCode.DONT_TRY_AGAIN,
reason: `${selector}: The owner has not authorized the order`,
};
// - for now it doesn't support more advanced cases where the order is authed during a pre-interaction
log.info(`Order on safe ${owner} not authed. Deleting order...`);
return dropOrder("The owner has not authorized the order");
case CustomErrorSelectors.INTERFACE_NOT_SUPPORTED:
log.info(
`${selector}: Order on safe ${owner} attempted to use a handler that is not supported. Deleting order...`
`Order type for safe ${owner}, failed IERC165 introspection check. Deleting order...`
);
return {
result: PollResultCode.DONT_TRY_AGAIN,
reason: `${selector}: The handler is not supported`,
};
return dropOrder("The order type failed IERC165 introspection check");
case CustomErrorSelectors.INVALID_FALLBACK_HANDLER:
log.info(
`${selector}: Order for safe ${owner} where the Safe does not have ExtensibleFallbackHandler set. Deleting order...`
`Order for safe ${owner} where the Safe does not have ExtensibleFallbackHandler set. Deleting order...`
);
return dropOrder(
"The safe does not have ExtensibleFallbackHandler set"
);
return {
result: PollResultCode.DONT_TRY_AGAIN,
reason: `${selector}: The safe does not have ExtensibleFallbackHandler set`,
};
case CustomErrorSelectors.INVALID_HANDLER:
log.info(
`${selector}: Order type for safe ${owner}, failed IERC165 introspection check. Deleting order...`
`Order on safe ${owner} attempted to use a handler that is not supported. Deleting order...`
);
return {
result: PollResultCode.DONT_TRY_AGAIN,
reason: `${selector}: The safe does not have the handler set`,
};
return dropOrder("The handler is not supported");
case CustomErrorSelectors.SWAP_GUARD_RESTRICTED:
log.info(
`${selector}: Order for safe ${owner} where the Safe has swap guard enabled. Deleting order...`
`Order for safe ${owner} where the Safe has swap guard enabled. Deleting order...`
);
return {
result: PollResultCode.DONT_TRY_AGAIN,
reason: `${selector}: The safe has swap guard enabled`,
};
return dropOrder("The conditional order didn't pass the swap guard");
// TODO: Add metrics to track this
case CustomErrorSelectors.ORDER_NOT_VALID:
case CustomErrorSelectors.POLL_TRY_NEXT_BLOCK:
Expand All @@ -239,49 +253,35 @@ export function handleOnChainCustomError(params: {
// the past.
// PollTryNextBlock: The conditional order has signalled that it should be polled again on the next block.
log.info(
`${selector}: Order on safe ${owner} not valid/signalled to try next block.`
`Order on safe ${owner} not valid/signalled to try next block.`
);
return {
result: PollResultCode.TRY_NEXT_BLOCK,
reason: `${selector}: ${message}`,
reason: msgWithSelector(parsedCustomError.message),
};
case CustomErrorSelectors.POLL_TRY_AT_BLOCK:
// The conditional order has signalled that it should be polled again on a specific block.
if (!blockNumberOrEpoch) {
throw new Error(
`Expected blockNumberOrEpoch to be defined for ${selector}`
);
}
return {
result: PollResultCode.TRY_ON_BLOCK,
blockNumber: blockNumberOrEpoch,
reason: `PollTryAtBlock: ${message}`,
blockNumber: parsedCustomError.blockNumberOrEpoch,
reason: msgWithSelector(parsedCustomError.message),
};
case CustomErrorSelectors.POLL_TRY_AT_EPOCH:
// The conditional order has signalled that it should be polled again on a specific epoch.
if (!blockNumberOrEpoch) {
throw new Error(
`Expected blockNumberOrEpoch to be defined for ${selector}`
);
}
return {
result: PollResultCode.TRY_AT_EPOCH,
epoch: blockNumberOrEpoch,
reason: `PollTryAtEpoch: ${message}`,
epoch: parsedCustomError.blockNumberOrEpoch,
reason: msgWithSelector(parsedCustomError.message),
};
case CustomErrorSelectors.POLL_NEVER:
// The conditional order has signalled that it should never be polled again.
return {
result: PollResultCode.DONT_TRY_AGAIN,
reason: `PollNever: ${message}`,
};
return dropOrder(parsedCustomError.message);
}
} catch (err) {
} catch (err: any) {
// Any errors thrown here can _ONLY_ come from non-compliant interfaces (ie. bad revert ABI encoding).
// We log the error, and return a DONT_TRY_AGAIN result.
// TODO: Add metrics to track this
const log = getLogger(logPrefix);
log.debug(`Non-compliant interface error thrown: ${err.message}`);
log.debug(
`Contract returned a non-interface compliant revert via getTradeableOrderWithSignature. Simulate: https://dashboard.tenderly.co/gp-v2/watch-tower-prod/simulator/new?network=${chainId}&contractAddress=${target}&rawFunctionInput=${callData}`
`Contract returned a non-compliant interface revert via getTradeableOrderWithSignature. Simulate: https://dashboard.tenderly.co/gp-v2/watch-tower-prod/simulator/new?network=${chainId}&contractAddress=${target}&rawFunctionInput=${callData}`
);
return {
result: PollResultCode.DONT_TRY_AGAIN,
Expand Down

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