ethers.js/packages/providers/src.ts/base-provider.ts
2022-03-25 03:57:43 -04:00

2201 lines
80 KiB
TypeScript

"use strict";
import {
Block, BlockTag, BlockWithTransactions, EventType, Filter, FilterByBlockHash, ForkEvent,
Listener, Log, Provider, TransactionReceipt, TransactionRequest, TransactionResponse
} from "@ethersproject/abstract-provider";
import { Base58 } from "@ethersproject/basex";
import { BigNumber, BigNumberish } from "@ethersproject/bignumber";
import { arrayify, BytesLike, concat, hexConcat, hexDataLength, hexDataSlice, hexlify, hexValue, hexZeroPad, isHexString } from "@ethersproject/bytes";
import { HashZero } from "@ethersproject/constants";
import { dnsEncode, namehash } from "@ethersproject/hash";
import { getNetwork, Network, Networkish } from "@ethersproject/networks";
import { Deferrable, defineReadOnly, getStatic, resolveProperties } from "@ethersproject/properties";
import { Transaction } from "@ethersproject/transactions";
import { sha256 } from "@ethersproject/sha2";
import { toUtf8Bytes, toUtf8String } from "@ethersproject/strings";
import { fetchJson, poll } from "@ethersproject/web";
import bech32 from "bech32";
import { Logger } from "@ethersproject/logger";
import { version } from "./_version";
const logger = new Logger(version);
import { Formatter } from "./formatter";
const MAX_CCIP_REDIRECTS = 10;
//////////////////////////////
// Event Serializeing
function checkTopic(topic: string): string {
if (topic == null) { return "null"; }
if (hexDataLength(topic) !== 32) {
logger.throwArgumentError("invalid topic", "topic", topic);
}
return topic.toLowerCase();
}
function serializeTopics(topics: Array<string | Array<string>>): string {
// Remove trailing null AND-topics; they are redundant
topics = topics.slice();
while (topics.length > 0 && topics[topics.length - 1] == null) { topics.pop(); }
return topics.map((topic) => {
if (Array.isArray(topic)) {
// Only track unique OR-topics
const unique: { [ topic: string ]: boolean } = { }
topic.forEach((topic) => {
unique[checkTopic(topic)] = true;
});
// The order of OR-topics does not matter
const sorted = Object.keys(unique);
sorted.sort();
return sorted.join("|");
} else {
return checkTopic(topic);
}
}).join("&");
}
function deserializeTopics(data: string): Array<string | Array<string>> {
if (data === "") { return [ ]; }
return data.split(/&/g).map((topic) => {
if (topic === "") { return [ ]; }
const comps = topic.split("|").map((topic) => {
return ((topic === "null") ? null: topic);
});
return ((comps.length === 1) ? comps[0]: comps);
});
}
function getEventTag(eventName: EventType): string {
if (typeof(eventName) === "string") {
eventName = eventName.toLowerCase();
if (hexDataLength(eventName) === 32) {
return "tx:" + eventName;
}
if (eventName.indexOf(":") === -1) {
return eventName;
}
} else if (Array.isArray(eventName)) {
return "filter:*:" + serializeTopics(eventName);
} else if (ForkEvent.isForkEvent(eventName)) {
logger.warn("not implemented");
throw new Error("not implemented");
} else if (eventName && typeof(eventName) === "object") {
return "filter:" + (eventName.address || "*") + ":" + serializeTopics(eventName.topics || []);
}
throw new Error("invalid event - " + eventName);
}
//////////////////////////////
// Helper Object
function getTime() {
return (new Date()).getTime();
}
function stall(duration: number): Promise<void> {
return new Promise((resolve) => {
setTimeout(resolve, duration);
});
}
//////////////////////////////
// Provider Object
/**
* EventType
* - "block"
* - "poll"
* - "didPoll"
* - "pending"
* - "error"
* - "network"
* - filter
* - topics array
* - transaction hash
*/
const PollableEvents = [ "block", "network", "pending", "poll" ];
export class Event {
readonly listener: Listener;
readonly once: boolean;
readonly tag: string;
_lastBlockNumber: number
_inflight: boolean;
constructor(tag: string, listener: Listener, once: boolean) {
defineReadOnly(this, "tag", tag);
defineReadOnly(this, "listener", listener);
defineReadOnly(this, "once", once);
this._lastBlockNumber = -2;
this._inflight = false;
}
get event(): EventType {
switch (this.type) {
case "tx":
return this.hash;
case "filter":
return this.filter;
}
return this.tag;
}
get type(): string {
return this.tag.split(":")[0]
}
get hash(): string {
const comps = this.tag.split(":");
if (comps[0] !== "tx") { return null; }
return comps[1];
}
get filter(): Filter {
const comps = this.tag.split(":");
if (comps[0] !== "filter") { return null; }
const address = comps[1];
const topics = deserializeTopics(comps[2]);
const filter: Filter = { };
if (topics.length > 0) { filter.topics = topics; }
if (address && address !== "*") { filter.address = address; }
return filter;
}
pollable(): boolean {
return (this.tag.indexOf(":") >= 0 || PollableEvents.indexOf(this.tag) >= 0);
}
}
export interface EnsResolver {
// Name this Resolver is associated with
readonly name: string;
// The address of the resolver
readonly address: string;
// Multichain address resolution (also normal address resolution)
// See: https://eips.ethereum.org/EIPS/eip-2304
getAddress(coinType?: 60): Promise<null | string>
// Contenthash field
// See: https://eips.ethereum.org/EIPS/eip-1577
getContentHash(): Promise<null | string>;
// Storage of text records
// See: https://eips.ethereum.org/EIPS/eip-634
getText(key: string): Promise<null | string>;
};
export interface EnsProvider {
resolveName(name: string): Promise<null | string>;
lookupAddress(address: string): Promise<null | string>;
getResolver(name: string): Promise<null | EnsResolver>;
}
type CoinInfo = {
symbol: string,
ilk?: string, // General family
prefix?: string, // Bech32 prefix
p2pkh?: number, // Pay-to-Public-Key-Hash Version
p2sh?: number, // Pay-to-Script-Hash Version
};
// https://github.com/satoshilabs/slips/blob/master/slip-0044.md
const coinInfos: { [ coinType: string ]: CoinInfo } = {
"0": { symbol: "btc", p2pkh: 0x00, p2sh: 0x05, prefix: "bc" },
"2": { symbol: "ltc", p2pkh: 0x30, p2sh: 0x32, prefix: "ltc" },
"3": { symbol: "doge", p2pkh: 0x1e, p2sh: 0x16 },
"60": { symbol: "eth", ilk: "eth" },
"61": { symbol: "etc", ilk: "eth" },
"700": { symbol: "xdai", ilk: "eth" },
};
function bytes32ify(value: number): string {
return hexZeroPad(BigNumber.from(value).toHexString(), 32);
}
// Compute the Base58Check encoded data (checksum is first 4 bytes of sha256d)
function base58Encode(data: Uint8Array): string {
return Base58.encode(concat([ data, hexDataSlice(sha256(sha256(data)), 0, 4) ]));
}
export interface Avatar {
url: string;
linkage: Array<{ type: string, content: string }>;
}
const matcherIpfs = new RegExp("^(ipfs):/\/(.*)$", "i");
const matchers = [
new RegExp("^(https):/\/(.*)$", "i"),
new RegExp("^(data):(.*)$", "i"),
matcherIpfs,
new RegExp("^eip155:[0-9]+/(erc[0-9]+):(.*)$", "i"),
];
function _parseString(result: string, start: number): null | string {
try {
return toUtf8String(_parseBytes(result, start));
} catch(error) { }
return null;
}
function _parseBytes(result: string, start: number): null | string {
if (result === "0x") { return null; }
const offset = BigNumber.from(hexDataSlice(result, start, start + 32)).toNumber();
const length = BigNumber.from(hexDataSlice(result, offset, offset + 32)).toNumber();
return hexDataSlice(result, offset + 32, offset + 32 + length);
}
// Trim off the ipfs:// prefix and return the default gateway URL
function getIpfsLink(link: string): string {
if (link.match(/^ipfs:\/\/ipfs\//i)) {
link = link.substring(12);
} else if (link.match(/^ipfs:\/\//i)) {
link = link.substring(7);
} else {
logger.throwArgumentError("unsupported IPFS format", "link", link);
}
return `https:/\/gateway.ipfs.io/ipfs/${ link }`;
}
function numPad(value: number): Uint8Array {
const result = arrayify(value);
if (result.length > 32) { throw new Error("internal; should not happen"); }
const padded = new Uint8Array(32);
padded.set(result, 32 - result.length);
return padded;
}
function bytesPad(value: Uint8Array): Uint8Array {
if ((value.length % 32) === 0) { return value; }
const result = new Uint8Array(Math.ceil(value.length / 32) * 32);
result.set(value);
return result;
}
// ABI Encodes a series of (bytes, bytes, ...)
function encodeBytes(datas: Array<BytesLike>) {
const result: Array<Uint8Array> = [ ];
let byteCount = 0;
// Add place-holders for pointers as we add items
for (let i = 0; i < datas.length; i++) {
result.push(null);
byteCount += 32;
}
for (let i = 0; i < datas.length; i++) {
const data = arrayify(datas[i]);
// Update the bytes offset
result[i] = numPad(byteCount);
// The length and padded value of data
result.push(numPad(data.length));
result.push(bytesPad(data));
byteCount += 32 + Math.ceil(data.length / 32) * 32;
}
return hexConcat(result);
}
export class Resolver implements EnsResolver {
readonly provider: BaseProvider;
readonly name: string;
readonly address: string;
readonly _resolvedAddress: null | string;
// For EIP-2544 names, the ancestor that provided the resolver
_supportsEip2544: null | Promise<boolean>;
// The resolvedAddress is only for creating a ReverseLookup resolver
constructor(provider: BaseProvider, address: string, name: string, resolvedAddress?: string) {
defineReadOnly(this, "provider", provider);
defineReadOnly(this, "name", name);
defineReadOnly(this, "address", provider.formatter.address(address));
defineReadOnly(this, "_resolvedAddress", resolvedAddress);
}
supportsWildcard(): Promise<boolean> {
if (!this._supportsEip2544) {
// supportsInterface(bytes4 = selector("resolve(bytes,bytes)"))
this._supportsEip2544 = this.provider.call({
to: this.address,
data: "0x01ffc9a79061b92300000000000000000000000000000000000000000000000000000000"
}).then((result) => {
return BigNumber.from(result).eq(1);
}).catch((error) => {
if (error.code === Logger.errors.CALL_EXCEPTION) { return false; }
// Rethrow the error: link is down, etc. Let future attempts retry.
this._supportsEip2544 = null;
throw error;
});
}
return this._supportsEip2544;
}
async _fetch(selector: string, parameters?: string): Promise<null | string> {
// e.g. keccak256("addr(bytes32,uint256)")
const tx = {
to: this.address,
ccipReadEnabled: true,
data: hexConcat([ selector, namehash(this.name), (parameters || "0x") ])
};
// Wildcard support; use EIP-2544 to resolve the request
let parseBytes = false;
if (await this.supportsWildcard()) {
parseBytes = true;
// selector("resolve(bytes,bytes)")
tx.data = hexConcat([ "0x9061b923", encodeBytes([ dnsEncode(this.name), tx.data ]) ]);
}
try {
let result = await this.provider.call(tx);
if ((arrayify(result).length % 32) === 4) {
logger.throwError("resolver threw error", Logger.errors.CALL_EXCEPTION, {
transaction: tx, data: result
});
}
if (parseBytes) { result = _parseBytes(result, 0); }
return result;
} catch (error) {
if (error.code === Logger.errors.CALL_EXCEPTION) { return null; }
throw error;
}
}
async _fetchBytes(selector: string, parameters?: string): Promise<null | string> {
const result = await this._fetch(selector, parameters);
if (result != null) { return _parseBytes(result, 0); }
return null;
}
_getAddress(coinType: number, hexBytes: string): string {
const coinInfo = coinInfos[String(coinType)];
if (coinInfo == null) {
logger.throwError(`unsupported coin type: ${ coinType }`, Logger.errors.UNSUPPORTED_OPERATION, {
operation: `getAddress(${ coinType })`
});
}
if (coinInfo.ilk === "eth") {
return this.provider.formatter.address(hexBytes);
}
const bytes = arrayify(hexBytes);
// P2PKH: OP_DUP OP_HASH160 <pubKeyHash> OP_EQUALVERIFY OP_CHECKSIG
if (coinInfo.p2pkh != null) {
const p2pkh = hexBytes.match(/^0x76a9([0-9a-f][0-9a-f])([0-9a-f]*)88ac$/);
if (p2pkh) {
const length = parseInt(p2pkh[1], 16);
if (p2pkh[2].length === length * 2 && length >= 1 && length <= 75) {
return base58Encode(concat([ [ coinInfo.p2pkh ], ("0x" + p2pkh[2]) ]));
}
}
}
// P2SH: OP_HASH160 <scriptHash> OP_EQUAL
if (coinInfo.p2sh != null) {
const p2sh = hexBytes.match(/^0xa9([0-9a-f][0-9a-f])([0-9a-f]*)87$/);
if (p2sh) {
const length = parseInt(p2sh[1], 16);
if (p2sh[2].length === length * 2 && length >= 1 && length <= 75) {
return base58Encode(concat([ [ coinInfo.p2sh ], ("0x" + p2sh[2]) ]));
}
}
}
// Bech32
if (coinInfo.prefix != null) {
const length = bytes[1];
// https://github.com/bitcoin/bips/blob/master/bip-0141.mediawiki#witness-program
let version = bytes[0];
if (version === 0x00) {
if (length !== 20 && length !== 32) {
version = -1;
}
} else {
version = -1;
}
if (version >= 0 && bytes.length === 2 + length && length >= 1 && length <= 75) {
const words = bech32.toWords(bytes.slice(2));
words.unshift(version);
return bech32.encode(coinInfo.prefix, words);
}
}
return null;
}
async getAddress(coinType?: number): Promise<string> {
if (coinType == null) { coinType = 60; }
// If Ethereum, use the standard `addr(bytes32)`
if (coinType === 60) {
try {
// keccak256("addr(bytes32)")
const result = await this._fetch("0x3b3b57de");
// No address
if (result === "0x" || result === HashZero) { return null; }
return this.provider.formatter.callAddress(result);
} catch (error) {
if (error.code === Logger.errors.CALL_EXCEPTION) { return null; }
throw error;
}
}
// keccak256("addr(bytes32,uint256")
const hexBytes = await this._fetchBytes("0xf1cb7e06", bytes32ify(coinType));
// No address
if (hexBytes == null || hexBytes === "0x") { return null; }
// Compute the address
const address = this._getAddress(coinType, hexBytes);
if (address == null) {
logger.throwError(`invalid or unsupported coin data`, Logger.errors.UNSUPPORTED_OPERATION, {
operation: `getAddress(${ coinType })`,
coinType: coinType,
data: hexBytes
});
}
return address;
}
async getAvatar(): Promise<null | Avatar> {
const linkage: Array<{ type: string, content: string }> = [ { type: "name", content: this.name } ];
try {
// test data for ricmoo.eth
//const avatar = "eip155:1/erc721:0x265385c7f4132228A0d54EB1A9e7460b91c0cC68/29233";
const avatar = await this.getText("avatar");
if (avatar == null) { return null; }
for (let i = 0; i < matchers.length; i++) {
const match = avatar.match(matchers[i]);
if (match == null) { continue; }
const scheme = match[1].toLowerCase();
switch (scheme) {
case "https":
linkage.push({ type: "url", content: avatar });
return { linkage, url: avatar };
case "data":
linkage.push({ type: "data", content: avatar });
return { linkage, url: avatar };
case "ipfs":
linkage.push({ type: "ipfs", content: avatar });
return { linkage, url: getIpfsLink(avatar) };
case "erc721":
case "erc1155": {
// Depending on the ERC type, use tokenURI(uint256) or url(uint256)
const selector = (scheme === "erc721") ? "0xc87b56dd": "0x0e89341c";
linkage.push({ type: scheme, content: avatar });
// The owner of this name
const owner = (this._resolvedAddress || await this.getAddress());
const comps = (match[2] || "").split("/");
if (comps.length !== 2) { return null; }
const addr = await this.provider.formatter.address(comps[0]);
const tokenId = hexZeroPad(BigNumber.from(comps[1]).toHexString(), 32);
// Check that this account owns the token
if (scheme === "erc721") {
// ownerOf(uint256 tokenId)
const tokenOwner = this.provider.formatter.callAddress(await this.provider.call({
to: addr, data: hexConcat([ "0x6352211e", tokenId ])
}));
if (owner !== tokenOwner) { return null; }
linkage.push({ type: "owner", content: tokenOwner });
} else if (scheme === "erc1155") {
// balanceOf(address owner, uint256 tokenId)
const balance = BigNumber.from(await this.provider.call({
to: addr, data: hexConcat([ "0x00fdd58e", hexZeroPad(owner, 32), tokenId ])
}));
if (balance.isZero()) { return null; }
linkage.push({ type: "balance", content: balance.toString() });
}
// Call the token contract for the metadata URL
const tx = {
to: this.provider.formatter.address(comps[0]),
data: hexConcat([ selector, tokenId ])
};
let metadataUrl = _parseString(await this.provider.call(tx), 0);
if (metadataUrl == null) { return null; }
linkage.push({ type: "metadata-url-base", content: metadataUrl });
// ERC-1155 allows a generic {id} in the URL
if (scheme === "erc1155") {
metadataUrl = metadataUrl.replace("{id}", tokenId.substring(2));
linkage.push({ type: "metadata-url-expanded", content: metadataUrl });
}
// Transform IPFS metadata links
if (metadataUrl.match(/^ipfs:/i)) {
metadataUrl = getIpfsLink(metadataUrl);
}
linkage.push({ type: "metadata-url", content: metadataUrl });
// Get the token metadata
const metadata = await fetchJson(metadataUrl);
if (!metadata) { return null; }
linkage.push({ type: "metadata", content: JSON.stringify(metadata) });
// Pull the image URL out
let imageUrl = metadata.image;
if (typeof(imageUrl) !== "string") { return null; }
if (imageUrl.match(/^(https:\/\/|data:)/i)) {
// Allow
} else {
// Transform IPFS link to gateway
const ipfs = imageUrl.match(matcherIpfs);
if (ipfs == null) { return null; }
linkage.push({ type: "url-ipfs", content: imageUrl });
imageUrl = getIpfsLink(imageUrl);
}
linkage.push({ type: "url", content: imageUrl });
return { linkage, url: imageUrl };
}
}
}
} catch (error) { }
return null;
}
async getContentHash(): Promise<string> {
// keccak256("contenthash()")
const hexBytes = await this._fetchBytes("0xbc1c58d1");
// No contenthash
if (hexBytes == null || hexBytes === "0x") { return null; }
// IPFS (CID: 1, Type: DAG-PB)
const ipfs = hexBytes.match(/^0xe3010170(([0-9a-f][0-9a-f])([0-9a-f][0-9a-f])([0-9a-f]*))$/);
if (ipfs) {
const length = parseInt(ipfs[3], 16);
if (ipfs[4].length === length * 2) {
return "ipfs:/\/" + Base58.encode("0x" + ipfs[1]);
}
}
// IPNS (CID: 1, Type: libp2p-key)
const ipns = hexBytes.match(/^0xe5010172(([0-9a-f][0-9a-f])([0-9a-f][0-9a-f])([0-9a-f]*))$/);
if (ipns) {
const length = parseInt(ipns[3], 16);
if (ipns[4].length === length * 2) {
return "ipns:/\/" + Base58.encode("0x" + ipns[1]);
}
}
// Swarm (CID: 1, Type: swarm-manifest; hash/length hard-coded to keccak256/32)
const swarm = hexBytes.match(/^0xe40101fa011b20([0-9a-f]*)$/)
if (swarm) {
if (swarm[1].length === (32 * 2)) {
return "bzz:/\/" + swarm[1]
}
}
return logger.throwError(`invalid or unsupported content hash data`, Logger.errors.UNSUPPORTED_OPERATION, {
operation: "getContentHash()",
data: hexBytes
});
}
async getText(key: string): Promise<string> {
// The key encoded as parameter to fetchBytes
let keyBytes = toUtf8Bytes(key);
// The nodehash consumes the first slot, so the string pointer targets
// offset 64, with the length at offset 64 and data starting at offset 96
keyBytes = concat([ bytes32ify(64), bytes32ify(keyBytes.length), keyBytes ]);
// Pad to word-size (32 bytes)
if ((keyBytes.length % 32) !== 0) {
keyBytes = concat([ keyBytes, hexZeroPad("0x", 32 - (key.length % 32)) ])
}
const hexBytes = await this._fetchBytes("0x59d1d43c", hexlify(keyBytes));
if (hexBytes == null || hexBytes === "0x") { return null; }
return toUtf8String(hexBytes);
}
}
let defaultFormatter: Formatter = null;
let nextPollId = 1;
export class BaseProvider extends Provider implements EnsProvider {
_networkPromise: Promise<Network>;
_network: Network;
_events: Array<Event>;
formatter: Formatter;
// To help mitigate the eventually consistent nature of the blockchain
// we keep a mapping of events we emit. If we emit an event X, we expect
// that a user should be able to query for that event in the callback,
// if the node returns null, we stall the response until we get back a
// meaningful value, since we may be hitting a re-org, or a node that
// has not indexed the event yet.
// Events:
// - t:{hash} - Transaction hash
// - b:{hash} - BlockHash
// - block - The most recent emitted block
_emitted: { [ eventName: string ]: number | "pending" };
_pollingInterval: number;
_poller: NodeJS.Timer;
_bootstrapPoll: NodeJS.Timer;
_lastBlockNumber: number;
_maxFilterBlockRange: number;
_fastBlockNumber: number;
_fastBlockNumberPromise: Promise<number>;
_fastQueryDate: number;
_maxInternalBlockNumber: number;
_internalBlockNumber: Promise<{ blockNumber: number, reqTime: number, respTime: number }>;
readonly anyNetwork: boolean;
disableCcipRead: boolean;
/**
* ready
*
* A Promise<Network> that resolves only once the provider is ready.
*
* Sub-classes that call the super with a network without a chainId
* MUST set this. Standard named networks have a known chainId.
*
*/
constructor(network: Networkish | Promise<Network>) {
logger.checkNew(new.target, Provider);
super();
// Events being listened to
this._events = [];
this._emitted = { block: -2 };
this.disableCcipRead = false;
this.formatter = new.target.getFormatter();
// If network is any, this Provider allows the underlying
// network to change dynamically, and we auto-detect the
// current network
defineReadOnly(this, "anyNetwork", (network === "any"));
if (this.anyNetwork) { network = this.detectNetwork(); }
if (network instanceof Promise) {
this._networkPromise = network;
// Squash any "unhandled promise" errors; that do not need to be handled
network.catch((error) => { });
// Trigger initial network setting (async)
this._ready().catch((error) => { });
} else {
const knownNetwork = getStatic<(network: Networkish) => Network>(new.target, "getNetwork")(network);
if (knownNetwork) {
defineReadOnly(this, "_network", knownNetwork);
this.emit("network", knownNetwork, null);
} else {
logger.throwArgumentError("invalid network", "network", network);
}
}
this._maxInternalBlockNumber = -1024;
this._lastBlockNumber = -2;
this._maxFilterBlockRange = 10;
this._pollingInterval = 4000;
this._fastQueryDate = 0;
}
async _ready(): Promise<Network> {
if (this._network == null) {
let network: Network = null;
if (this._networkPromise) {
try {
network = await this._networkPromise;
} catch (error) { }
}
// Try the Provider's network detection (this MUST throw if it cannot)
if (network == null) {
network = await this.detectNetwork();
}
// This should never happen; every Provider sub-class should have
// suggested a network by here (or have thrown).
if (!network) {
logger.throwError("no network detected", Logger.errors.UNKNOWN_ERROR, { });
}
// Possible this call stacked so do not call defineReadOnly again
if (this._network == null) {
if (this.anyNetwork) {
this._network = network;
} else {
defineReadOnly(this, "_network", network);
}
this.emit("network", network, null);
}
}
return this._network;
}
// This will always return the most recently established network.
// For "any", this can change (a "network" event is emitted before
// any change is reflected); otherwise this cannot change
get ready(): Promise<Network> {
return poll(() => {
return this._ready().then((network) => {
return network;
}, (error) => {
// If the network isn't running yet, we will wait
if (error.code === Logger.errors.NETWORK_ERROR && error.event === "noNetwork") {
return undefined;
}
throw error;
});
});
}
// @TODO: Remove this and just create a singleton formatter
static getFormatter(): Formatter {
if (defaultFormatter == null) {
defaultFormatter = new Formatter();
}
return defaultFormatter;
}
// @TODO: Remove this and just use getNetwork
static getNetwork(network: Networkish): Network {
return getNetwork((network == null) ? "homestead": network);
}
async ccipReadFetch(tx: Transaction, calldata: string, urls: Array<string>): Promise<null | string> {
if (this.disableCcipRead || urls.length === 0) { return null; }
const sender = tx.to.toLowerCase();
const data = calldata.toLowerCase();
const errorMessages: Array<string> = [ ];
for (let i = 0; i < urls.length; i++) {
const url = urls[i];
// URL expansion
const href = url.replace("{sender}", sender).replace("{data}", data);
// If no {data} is present, use POST; otherwise GET
const json: string | null = (url.indexOf("{data}") >= 0) ? null: JSON.stringify({ data, sender });
const result = await fetchJson({ url: href, errorPassThrough: true }, json, (value, response) => {
value.status = response.statusCode;
return value;
});
if (result.data) { return result.data; }
const errorMessage = (result.message || "unknown error");
// 4xx indicates the result is not present; stop
if (result.status >= 400 && result.status < 500) {
return logger.throwError(`response not found during CCIP fetch: ${ errorMessage }`, Logger.errors.SERVER_ERROR, { url, errorMessage });
}
// 5xx indicates server issue; try the next url
errorMessages.push(errorMessage);
}
return logger.throwError(`error encountered during CCIP fetch: ${ errorMessages.map((m) => JSON.stringify(m)).join(", ") }`, Logger.errors.SERVER_ERROR, {
urls, errorMessages
});
}
// Fetches the blockNumber, but will reuse any result that is less
// than maxAge old or has been requested since the last request
async _getInternalBlockNumber(maxAge: number): Promise<number> {
await this._ready();
// Allowing stale data up to maxAge old
if (maxAge > 0) {
// While there are pending internal block requests...
while (this._internalBlockNumber) {
// ..."remember" which fetch we started with
const internalBlockNumber = this._internalBlockNumber;
try {
// Check the result is not too stale
const result = await internalBlockNumber;
if ((getTime() - result.respTime) <= maxAge) {
return result.blockNumber;
}
// Too old; fetch a new value
break;
} catch(error) {
// The fetch rejected; if we are the first to get the
// rejection, drop through so we replace it with a new
// fetch; all others blocked will then get that fetch
// which won't match the one they "remembered" and loop
if (this._internalBlockNumber === internalBlockNumber) {
break;
}
}
}
}
const reqTime = getTime();
const checkInternalBlockNumber = resolveProperties({
blockNumber: this.perform("getBlockNumber", { }),
networkError: this.getNetwork().then((network) => (null), (error) => (error))
}).then(({ blockNumber, networkError }) => {
if (networkError) {
// Unremember this bad internal block number
if (this._internalBlockNumber === checkInternalBlockNumber) {
this._internalBlockNumber = null;
}
throw networkError;
}
const respTime = getTime();
blockNumber = BigNumber.from(blockNumber).toNumber();
if (blockNumber < this._maxInternalBlockNumber) { blockNumber = this._maxInternalBlockNumber; }
this._maxInternalBlockNumber = blockNumber;
this._setFastBlockNumber(blockNumber); // @TODO: Still need this?
return { blockNumber, reqTime, respTime };
});
this._internalBlockNumber = checkInternalBlockNumber;
// Swallow unhandled exceptions; if needed they are handled else where
checkInternalBlockNumber.catch((error) => {
// Don't null the dead (rejected) fetch, if it has already been updated
if (this._internalBlockNumber === checkInternalBlockNumber) {
this._internalBlockNumber = null;
}
});
return (await checkInternalBlockNumber).blockNumber;
}
async poll(): Promise<void> {
const pollId = nextPollId++;
// Track all running promises, so we can trigger a post-poll once they are complete
const runners: Array<Promise<void>> = [];
let blockNumber: number = null;
try {
blockNumber = await this._getInternalBlockNumber(100 + this.pollingInterval / 2);
} catch (error) {
this.emit("error", error);
return;
}
this._setFastBlockNumber(blockNumber);
// Emit a poll event after we have the latest (fast) block number
this.emit("poll", pollId, blockNumber);
// If the block has not changed, meh.
if (blockNumber === this._lastBlockNumber) {
this.emit("didPoll", pollId);
return;
}
// First polling cycle, trigger a "block" events
if (this._emitted.block === -2) {
this._emitted.block = blockNumber - 1;
}
if (Math.abs((<number>(this._emitted.block)) - blockNumber) > 1000) {
logger.warn(`network block skew detected; skipping block events (emitted=${ this._emitted.block } blockNumber${ blockNumber })`);
this.emit("error", logger.makeError("network block skew detected", Logger.errors.NETWORK_ERROR, {
blockNumber: blockNumber,
event: "blockSkew",
previousBlockNumber: this._emitted.block
}));
this.emit("block", blockNumber);
} else {
// Notify all listener for each block that has passed
for (let i = (<number>this._emitted.block) + 1; i <= blockNumber; i++) {
this.emit("block", i);
}
}
// The emitted block was updated, check for obsolete events
if ((<number>this._emitted.block) !== blockNumber) {
this._emitted.block = blockNumber;
Object.keys(this._emitted).forEach((key) => {
// The block event does not expire
if (key === "block") { return; }
// The block we were at when we emitted this event
const eventBlockNumber = this._emitted[key];
// We cannot garbage collect pending transactions or blocks here
// They should be garbage collected by the Provider when setting
// "pending" events
if (eventBlockNumber === "pending") { return; }
// Evict any transaction hashes or block hashes over 12 blocks
// old, since they should not return null anyways
if (blockNumber - eventBlockNumber > 12) {
delete this._emitted[key];
}
});
}
// First polling cycle
if (this._lastBlockNumber === -2) {
this._lastBlockNumber = blockNumber - 1;
}
// Find all transaction hashes we are waiting on
this._events.forEach((event) => {
switch (event.type) {
case "tx": {
const hash = event.hash;
let runner = this.getTransactionReceipt(hash).then((receipt) => {
if (!receipt || receipt.blockNumber == null) { return null; }
this._emitted["t:" + hash] = receipt.blockNumber;
this.emit(hash, receipt);
return null;
}).catch((error: Error) => { this.emit("error", error); });
runners.push(runner);
break;
}
case "filter": {
// We only allow a single getLogs to be in-flight at a time
if (!event._inflight) {
event._inflight = true;
// Filter from the last known event; due to load-balancing
// and some nodes returning updated block numbers before
// indexing events, a logs result with 0 entries cannot be
// trusted and we must retry a range which includes it again
const filter = event.filter;
filter.fromBlock = event._lastBlockNumber + 1;
filter.toBlock = blockNumber;
// Prevent fitler ranges from growing too wild
if (filter.toBlock - this._maxFilterBlockRange > filter.fromBlock) {
filter.fromBlock = filter.toBlock - this._maxFilterBlockRange;
}
const runner = this.getLogs(filter).then((logs) => {
// Allow the next getLogs
event._inflight = false;
if (logs.length === 0) { return; }
logs.forEach((log: Log) => {
// Only when we get an event for a given block number
// can we trust the events are indexed
if (log.blockNumber > event._lastBlockNumber) {
event._lastBlockNumber = log.blockNumber;
}
// Make sure we stall requests to fetch blocks and txs
this._emitted["b:" + log.blockHash] = log.blockNumber;
this._emitted["t:" + log.transactionHash] = log.blockNumber;
this.emit(filter, log);
});
}).catch((error: Error) => {
this.emit("error", error);
// Allow another getLogs (the range was not updated)
event._inflight = false;
});
runners.push(runner);
}
break;
}
}
});
this._lastBlockNumber = blockNumber;
// Once all events for this loop have been processed, emit "didPoll"
Promise.all(runners).then(() => {
this.emit("didPoll", pollId);
}).catch((error) => { this.emit("error", error); });
return;
}
// Deprecated; do not use this
resetEventsBlock(blockNumber: number): void {
this._lastBlockNumber = blockNumber - 1;
if (this.polling) { this.poll(); }
}
get network(): Network {
return this._network;
}
// This method should query the network if the underlying network
// can change, such as when connected to a JSON-RPC backend
async detectNetwork(): Promise<Network> {
return logger.throwError("provider does not support network detection", Logger.errors.UNSUPPORTED_OPERATION, {
operation: "provider.detectNetwork"
});
}
async getNetwork(): Promise<Network> {
const network = await this._ready();
// Make sure we are still connected to the same network; this is
// only an external call for backends which can have the underlying
// network change spontaneously
const currentNetwork = await this.detectNetwork();
if (network.chainId !== currentNetwork.chainId) {
// We are allowing network changes, things can get complex fast;
// make sure you know what you are doing if you use "any"
if (this.anyNetwork) {
this._network = currentNetwork;
// Reset all internal block number guards and caches
this._lastBlockNumber = -2;
this._fastBlockNumber = null;
this._fastBlockNumberPromise = null;
this._fastQueryDate = 0;
this._emitted.block = -2;
this._maxInternalBlockNumber = -1024;
this._internalBlockNumber = null;
// The "network" event MUST happen before this method resolves
// so any events have a chance to unregister, so we stall an
// additional event loop before returning from /this/ call
this.emit("network", currentNetwork, network);
await stall(0);
return this._network;
}
const error = logger.makeError("underlying network changed", Logger.errors.NETWORK_ERROR, {
event: "changed",
network: network,
detectedNetwork: currentNetwork
});
this.emit("error", error);
throw error;
}
return network;
}
get blockNumber(): number {
this._getInternalBlockNumber(100 + this.pollingInterval / 2).then((blockNumber) => {
this._setFastBlockNumber(blockNumber);
}, (error) => { });
return (this._fastBlockNumber != null) ? this._fastBlockNumber: -1;
}
get polling(): boolean {
return (this._poller != null);
}
set polling(value: boolean) {
if (value && !this._poller) {
this._poller = setInterval(() => { this.poll(); }, this.pollingInterval);
if (!this._bootstrapPoll) {
this._bootstrapPoll = setTimeout(() => {
this.poll();
// We block additional polls until the polling interval
// is done, to prevent overwhelming the poll function
this._bootstrapPoll = setTimeout(() => {
// If polling was disabled, something may require a poke
// since starting the bootstrap poll and it was disabled
if (!this._poller) { this.poll(); }
// Clear out the bootstrap so we can do another
this._bootstrapPoll = null;
}, this.pollingInterval);
}, 0);
}
} else if (!value && this._poller) {
clearInterval(this._poller);
this._poller = null;
}
}
get pollingInterval(): number {
return this._pollingInterval;
}
set pollingInterval(value: number) {
if (typeof(value) !== "number" || value <= 0 || parseInt(String(value)) != value) {
throw new Error("invalid polling interval");
}
this._pollingInterval = value;
if (this._poller) {
clearInterval(this._poller);
this._poller = setInterval(() => { this.poll(); }, this._pollingInterval);
}
}
_getFastBlockNumber(): Promise<number> {
const now = getTime();
// Stale block number, request a newer value
if ((now - this._fastQueryDate) > 2 * this._pollingInterval) {
this._fastQueryDate = now;
this._fastBlockNumberPromise = this.getBlockNumber().then((blockNumber) => {
if (this._fastBlockNumber == null || blockNumber > this._fastBlockNumber) {
this._fastBlockNumber = blockNumber;
}
return this._fastBlockNumber;
});
}
return this._fastBlockNumberPromise;
}
_setFastBlockNumber(blockNumber: number): void {
// Older block, maybe a stale request
if (this._fastBlockNumber != null && blockNumber < this._fastBlockNumber) { return; }
// Update the time we updated the blocknumber
this._fastQueryDate = getTime();
// Newer block number, use it
if (this._fastBlockNumber == null || blockNumber > this._fastBlockNumber) {
this._fastBlockNumber = blockNumber;
this._fastBlockNumberPromise = Promise.resolve(blockNumber);
}
}
async waitForTransaction(transactionHash: string, confirmations?: number, timeout?: number): Promise<TransactionReceipt> {
return this._waitForTransaction(transactionHash, (confirmations == null) ? 1: confirmations, timeout || 0, null);
}
async _waitForTransaction(transactionHash: string, confirmations: number, timeout: number, replaceable: { data: string, from: string, nonce: number, to: string, value: BigNumber, startBlock: number }): Promise<TransactionReceipt> {
const receipt = await this.getTransactionReceipt(transactionHash);
// Receipt is already good
if ((receipt ? receipt.confirmations: 0) >= confirmations) { return receipt; }
// Poll until the receipt is good...
return new Promise((resolve, reject) => {
const cancelFuncs: Array<() => void> = [];
let done = false;
const alreadyDone = function() {
if (done) { return true; }
done = true;
cancelFuncs.forEach((func) => { func(); });
return false;
};
const minedHandler = (receipt: TransactionReceipt) => {
if (receipt.confirmations < confirmations) { return; }
if (alreadyDone()) { return; }
resolve(receipt);
}
this.on(transactionHash, minedHandler);
cancelFuncs.push(() => { this.removeListener(transactionHash, minedHandler); });
if (replaceable) {
let lastBlockNumber = replaceable.startBlock;
let scannedBlock: number = null;
const replaceHandler = async (blockNumber: number) => {
if (done) { return; }
// Wait 1 second; this is only used in the case of a fault, so
// we will trade off a little bit of latency for more consistent
// results and fewer JSON-RPC calls
await stall(1000);
this.getTransactionCount(replaceable.from).then(async (nonce) => {
if (done) { return; }
if (nonce <= replaceable.nonce) {
lastBlockNumber = blockNumber;
} else {
// First check if the transaction was mined
{
const mined = await this.getTransaction(transactionHash);
if (mined && mined.blockNumber != null) { return; }
}
// First time scanning. We start a little earlier for some
// wiggle room here to handle the eventually consistent nature
// of blockchain (e.g. the getTransactionCount was for a
// different block)
if (scannedBlock == null) {
scannedBlock = lastBlockNumber - 3;
if (scannedBlock < replaceable.startBlock) {
scannedBlock = replaceable.startBlock;
}
}
while (scannedBlock <= blockNumber) {
if (done) { return; }
const block = await this.getBlockWithTransactions(scannedBlock);
for (let ti = 0; ti < block.transactions.length; ti++) {
const tx = block.transactions[ti];
// Successfully mined!
if (tx.hash === transactionHash) { return; }
// Matches our transaction from and nonce; its a replacement
if (tx.from === replaceable.from && tx.nonce === replaceable.nonce) {
if (done) { return; }
// Get the receipt of the replacement
const receipt = await this.waitForTransaction(tx.hash, confirmations);
// Already resolved or rejected (prolly a timeout)
if (alreadyDone()) { return; }
// The reason we were replaced
let reason = "replaced";
if (tx.data === replaceable.data && tx.to === replaceable.to && tx.value.eq(replaceable.value)) {
reason = "repriced";
} else if (tx.data === "0x" && tx.from === tx.to && tx.value.isZero()) {
reason = "cancelled"
}
// Explain why we were replaced
reject(logger.makeError("transaction was replaced", Logger.errors.TRANSACTION_REPLACED, {
cancelled: (reason === "replaced" || reason === "cancelled"),
reason,
replacement: this._wrapTransaction(tx),
hash: transactionHash,
receipt
}));
return;
}
}
scannedBlock++;
}
}
if (done) { return; }
this.once("block", replaceHandler);
}, (error) => {
if (done) { return; }
this.once("block", replaceHandler);
});
};
if (done) { return; }
this.once("block", replaceHandler);
cancelFuncs.push(() => {
this.removeListener("block", replaceHandler);
});
}
if (typeof(timeout) === "number" && timeout > 0) {
const timer = setTimeout(() => {
if (alreadyDone()) { return; }
reject(logger.makeError("timeout exceeded", Logger.errors.TIMEOUT, { timeout: timeout }));
}, timeout);
if (timer.unref) { timer.unref(); }
cancelFuncs.push(() => { clearTimeout(timer); });
}
});
}
async getBlockNumber(): Promise<number> {
return this._getInternalBlockNumber(0);
}
async getGasPrice(): Promise<BigNumber> {
await this.getNetwork();
const result = await this.perform("getGasPrice", { });
try {
return BigNumber.from(result);
} catch (error) {
return logger.throwError("bad result from backend", Logger.errors.SERVER_ERROR, {
method: "getGasPrice",
result, error
});
}
}
async getBalance(addressOrName: string | Promise<string>, blockTag?: BlockTag | Promise<BlockTag>): Promise<BigNumber> {
await this.getNetwork();
const params = await resolveProperties({
address: this._getAddress(addressOrName),
blockTag: this._getBlockTag(blockTag)
});
const result = await this.perform("getBalance", params);
try {
return BigNumber.from(result);
} catch (error) {
return logger.throwError("bad result from backend", Logger.errors.SERVER_ERROR, {
method: "getBalance",
params, result, error
});
}
}
async getTransactionCount(addressOrName: string | Promise<string>, blockTag?: BlockTag | Promise<BlockTag>): Promise<number> {
await this.getNetwork();
const params = await resolveProperties({
address: this._getAddress(addressOrName),
blockTag: this._getBlockTag(blockTag)
});
const result = await this.perform("getTransactionCount", params);
try {
return BigNumber.from(result).toNumber();
} catch (error) {
return logger.throwError("bad result from backend", Logger.errors.SERVER_ERROR, {
method: "getTransactionCount",
params, result, error
});
}
}
async getCode(addressOrName: string | Promise<string>, blockTag?: BlockTag | Promise<BlockTag>): Promise<string> {
await this.getNetwork();
const params = await resolveProperties({
address: this._getAddress(addressOrName),
blockTag: this._getBlockTag(blockTag)
});
const result = await this.perform("getCode", params);
try {
return hexlify(result);
} catch (error) {
return logger.throwError("bad result from backend", Logger.errors.SERVER_ERROR, {
method: "getCode",
params, result, error
});
}
}
async getStorageAt(addressOrName: string | Promise<string>, position: BigNumberish | Promise<BigNumberish>, blockTag?: BlockTag | Promise<BlockTag>): Promise<string> {
await this.getNetwork();
const params = await resolveProperties({
address: this._getAddress(addressOrName),
blockTag: this._getBlockTag(blockTag),
position: Promise.resolve(position).then((p) => hexValue(p))
});
const result = await this.perform("getStorageAt", params);
try {
return hexlify(result);
} catch (error) {
return logger.throwError("bad result from backend", Logger.errors.SERVER_ERROR, {
method: "getStorageAt",
params, result, error
});
}
}
// This should be called by any subclass wrapping a TransactionResponse
_wrapTransaction(tx: Transaction, hash?: string, startBlock?: number): TransactionResponse {
if (hash != null && hexDataLength(hash) !== 32) { throw new Error("invalid response - sendTransaction"); }
const result = <TransactionResponse>tx;
// Check the hash we expect is the same as the hash the server reported
if (hash != null && tx.hash !== hash) {
logger.throwError("Transaction hash mismatch from Provider.sendTransaction.", Logger.errors.UNKNOWN_ERROR, { expectedHash: tx.hash, returnedHash: hash });
}
result.wait = async (confirms?: number, timeout?: number) => {
if (confirms == null) { confirms = 1; }
if (timeout == null) { timeout = 0; }
// Get the details to detect replacement
let replacement = undefined;
if (confirms !== 0 && startBlock != null) {
replacement = {
data: tx.data,
from: tx.from,
nonce: tx.nonce,
to: tx.to,
value: tx.value,
startBlock
};
}
const receipt = await this._waitForTransaction(tx.hash, confirms, timeout, replacement);
if (receipt == null && confirms === 0) { return null; }
// No longer pending, allow the polling loop to garbage collect this
this._emitted["t:" + tx.hash] = receipt.blockNumber;
if (receipt.status === 0) {
logger.throwError("transaction failed", Logger.errors.CALL_EXCEPTION, {
transactionHash: tx.hash,
transaction: tx,
receipt: receipt
});
}
return receipt;
};
return result;
}
async sendTransaction(signedTransaction: string | Promise<string>): Promise<TransactionResponse> {
await this.getNetwork();
const hexTx = await Promise.resolve(signedTransaction).then(t => hexlify(t));
const tx = this.formatter.transaction(signedTransaction);
if (tx.confirmations == null) { tx.confirmations = 0; }
const blockNumber = await this._getInternalBlockNumber(100 + 2 * this.pollingInterval);
try {
const hash = await this.perform("sendTransaction", { signedTransaction: hexTx });
return this._wrapTransaction(tx, hash, blockNumber);
} catch (error) {
(<any>error).transaction = tx;
(<any>error).transactionHash = tx.hash;
throw error;
}
}
async _getTransactionRequest(transaction: Deferrable<TransactionRequest>): Promise<Transaction> {
const values: any = await transaction;
const tx: any = { };
["from", "to"].forEach((key) => {
if (values[key] == null) { return; }
tx[key] = Promise.resolve(values[key]).then((v) => (v ? this._getAddress(v): null))
});
["gasLimit", "gasPrice", "maxFeePerGas", "maxPriorityFeePerGas", "value"].forEach((key) => {
if (values[key] == null) { return; }
tx[key] = Promise.resolve(values[key]).then((v) => (v ? BigNumber.from(v): null));
});
["type"].forEach((key) => {
if (values[key] == null) { return; }
tx[key] = Promise.resolve(values[key]).then((v) => ((v != null) ? v: null));
});
if (values.accessList) {
tx.accessList = this.formatter.accessList(values.accessList);
}
["data"].forEach((key) => {
if (values[key] == null) { return; }
tx[key] = Promise.resolve(values[key]).then((v) => (v ? hexlify(v): null));
});
return this.formatter.transactionRequest(await resolveProperties(tx));
}
async _getFilter(filter: Filter | FilterByBlockHash | Promise<Filter | FilterByBlockHash>): Promise<Filter | FilterByBlockHash> {
filter = await filter;
const result: any = { };
if (filter.address != null) {
result.address = this._getAddress(filter.address);
}
["blockHash", "topics"].forEach((key) => {
if ((<any>filter)[key] == null) { return; }
result[key] = (<any>filter)[key];
});
["fromBlock", "toBlock"].forEach((key) => {
if ((<any>filter)[key] == null) { return; }
result[key] = this._getBlockTag((<any>filter)[key]);
});
return this.formatter.filter(await resolveProperties(result));
}
async _call(transaction: TransactionRequest, blockTag: BlockTag, attempt: number): Promise<string> {
if (attempt >= MAX_CCIP_REDIRECTS) {
logger.throwError("CCIP read exceeded maximum redirections", Logger.errors.SERVER_ERROR, {
redirects: attempt, transaction
});
}
const txSender = transaction.to;
const result = await this.perform("call", { transaction, blockTag });
// CCIP Read request via OffchainLookup(address,string[],bytes,bytes4,bytes)
if (attempt >= 0 && blockTag === "latest" && txSender != null && result.substring(0, 10) === "0x556f1830" && (hexDataLength(result) % 32 === 4)) {
try {
const data = hexDataSlice(result, 4);
// Check the sender of the OffchainLookup matches the transaction
const sender = hexDataSlice(data, 0, 32);
if (!BigNumber.from(sender).eq(txSender)) {
logger.throwError("CCIP Read sender did not match", Logger.errors.CALL_EXCEPTION, {
name: "OffchainLookup",
signature: "OffchainLookup(address,string[],bytes,bytes4,bytes)",
transaction, data: result
});
}
// Read the URLs from the response
const urls: Array<string> = [];
const urlsOffset = BigNumber.from(hexDataSlice(data, 32, 64)).toNumber();
const urlsLength = BigNumber.from(hexDataSlice(data, urlsOffset, urlsOffset + 32)).toNumber();
const urlsData = hexDataSlice(data, urlsOffset + 32);
for (let u = 0; u < urlsLength; u++) {
const url = _parseString(urlsData, u * 32);
if (url == null) {
logger.throwError("CCIP Read contained corrupt URL string", Logger.errors.CALL_EXCEPTION, {
name: "OffchainLookup",
signature: "OffchainLookup(address,string[],bytes,bytes4,bytes)",
transaction, data: result
});
}
urls.push(url);
}
// Get the CCIP calldata to forward
const calldata = _parseBytes(data, 64);
// Get the callbackSelector (bytes4)
if (!BigNumber.from(hexDataSlice(data, 100, 128)).isZero()) {
logger.throwError("CCIP Read callback selector included junk", Logger.errors.CALL_EXCEPTION, {
name: "OffchainLookup",
signature: "OffchainLookup(address,string[],bytes,bytes4,bytes)",
transaction, data: result
});
}
const callbackSelector = hexDataSlice(data, 96, 100);
// Get the extra data to send back to the contract as context
const extraData = _parseBytes(data, 128);
const ccipResult = await this.ccipReadFetch(<Transaction>transaction, calldata, urls);
if (ccipResult == null) {
logger.throwError("CCIP Read disabled or provided no URLs", Logger.errors.CALL_EXCEPTION, {
name: "OffchainLookup",
signature: "OffchainLookup(address,string[],bytes,bytes4,bytes)",
transaction, data: result
});
}
const tx = {
to: txSender,
data: hexConcat([ callbackSelector, encodeBytes([ ccipResult, extraData ]) ])
};
return this._call(tx, blockTag, attempt + 1);
} catch (error) {
if (error.code === Logger.errors.SERVER_ERROR) { throw error; }
}
}
try {
return hexlify(result);
} catch (error) {
return logger.throwError("bad result from backend", Logger.errors.SERVER_ERROR, {
method: "call",
params: { transaction, blockTag }, result, error
});
}
}
async call(transaction: Deferrable<TransactionRequest>, blockTag?: BlockTag | Promise<BlockTag>): Promise<string> {
await this.getNetwork();
const resolved = await resolveProperties({
transaction: this._getTransactionRequest(transaction),
blockTag: this._getBlockTag(blockTag),
ccipReadEnabled: Promise.resolve(transaction.ccipReadEnabled)
});
return this._call(resolved.transaction, resolved.blockTag, resolved.ccipReadEnabled ? 0: -1);
}
async estimateGas(transaction: Deferrable<TransactionRequest>): Promise<BigNumber> {
await this.getNetwork();
const params = await resolveProperties({
transaction: this._getTransactionRequest(transaction)
});
const result = await this.perform("estimateGas", params);
try {
return BigNumber.from(result);
} catch (error) {
return logger.throwError("bad result from backend", Logger.errors.SERVER_ERROR, {
method: "estimateGas",
params, result, error
});
}
}
async _getAddress(addressOrName: string | Promise<string>): Promise<string> {
addressOrName = await addressOrName;
if (typeof(addressOrName) !== "string") {
logger.throwArgumentError("invalid address or ENS name", "name", addressOrName);
}
const address = await this.resolveName(addressOrName);
if (address == null) {
logger.throwError("ENS name not configured", Logger.errors.UNSUPPORTED_OPERATION, {
operation: `resolveName(${ JSON.stringify(addressOrName) })`
});
}
return address;
}
async _getBlock(blockHashOrBlockTag: BlockTag | string | Promise<BlockTag | string>, includeTransactions?: boolean): Promise<Block | BlockWithTransactions> {
await this.getNetwork();
blockHashOrBlockTag = await blockHashOrBlockTag;
// If blockTag is a number (not "latest", etc), this is the block number
let blockNumber = -128;
const params: { [key: string]: any } = {
includeTransactions: !!includeTransactions
};
if (isHexString(blockHashOrBlockTag, 32)) {
params.blockHash = blockHashOrBlockTag;
} else {
try {
params.blockTag = await this._getBlockTag(blockHashOrBlockTag);
if (isHexString(params.blockTag)) {
blockNumber = parseInt(params.blockTag.substring(2), 16);
}
} catch (error) {
logger.throwArgumentError("invalid block hash or block tag", "blockHashOrBlockTag", blockHashOrBlockTag);
}
}
return poll(async () => {
const block = await this.perform("getBlock", params);
// Block was not found
if (block == null) {
// For blockhashes, if we didn't say it existed, that blockhash may
// not exist. If we did see it though, perhaps from a log, we know
// it exists, and this node is just not caught up yet.
if (params.blockHash != null) {
if (this._emitted["b:" + params.blockHash] == null) { return null; }
}
// For block tags, if we are asking for a future block, we return null
if (params.blockTag != null) {
if (blockNumber > this._emitted.block) { return null; }
}
// Retry on the next block
return undefined;
}
// Add transactions
if (includeTransactions) {
let blockNumber: number = null;
for (let i = 0; i < block.transactions.length; i++) {
const tx = block.transactions[i];
if (tx.blockNumber == null) {
tx.confirmations = 0;
} else if (tx.confirmations == null) {
if (blockNumber == null) {
blockNumber = await this._getInternalBlockNumber(100 + 2 * this.pollingInterval);
}
// Add the confirmations using the fast block number (pessimistic)
let confirmations = (blockNumber - tx.blockNumber) + 1;
if (confirmations <= 0) { confirmations = 1; }
tx.confirmations = confirmations;
}
}
const blockWithTxs: any = this.formatter.blockWithTransactions(block);
blockWithTxs.transactions = blockWithTxs.transactions.map((tx: TransactionResponse) => this._wrapTransaction(tx));
return blockWithTxs;
}
return this.formatter.block(block);
}, { oncePoll: this });
}
getBlock(blockHashOrBlockTag: BlockTag | string | Promise<BlockTag | string>): Promise<Block> {
return <Promise<Block>>(this._getBlock(blockHashOrBlockTag, false));
}
getBlockWithTransactions(blockHashOrBlockTag: BlockTag | string | Promise<BlockTag | string>): Promise<BlockWithTransactions> {
return <Promise<BlockWithTransactions>>(this._getBlock(blockHashOrBlockTag, true));
}
async getTransaction(transactionHash: string | Promise<string>): Promise<TransactionResponse> {
await this.getNetwork();
transactionHash = await transactionHash;
const params = { transactionHash: this.formatter.hash(transactionHash, true) };
return poll(async () => {
const result = await this.perform("getTransaction", params);
if (result == null) {
if (this._emitted["t:" + transactionHash] == null) {
return null;
}
return undefined;
}
const tx = this.formatter.transactionResponse(result);
if (tx.blockNumber == null) {
tx.confirmations = 0;
} else if (tx.confirmations == null) {
const blockNumber = await this._getInternalBlockNumber(100 + 2 * this.pollingInterval);
// Add the confirmations using the fast block number (pessimistic)
let confirmations = (blockNumber - tx.blockNumber) + 1;
if (confirmations <= 0) { confirmations = 1; }
tx.confirmations = confirmations;
}
return this._wrapTransaction(tx);
}, { oncePoll: this });
}
async getTransactionReceipt(transactionHash: string | Promise<string>): Promise<TransactionReceipt> {
await this.getNetwork();
transactionHash = await transactionHash;
const params = { transactionHash: this.formatter.hash(transactionHash, true) };
return poll(async () => {
const result = await this.perform("getTransactionReceipt", params);
if (result == null) {
if (this._emitted["t:" + transactionHash] == null) {
return null;
}
return undefined;
}
// "geth-etc" returns receipts before they are ready
if (result.blockHash == null) { return undefined; }
const receipt = this.formatter.receipt(result);
if (receipt.blockNumber == null) {
receipt.confirmations = 0;
} else if (receipt.confirmations == null) {
const blockNumber = await this._getInternalBlockNumber(100 + 2 * this.pollingInterval);
// Add the confirmations using the fast block number (pessimistic)
let confirmations = (blockNumber - receipt.blockNumber) + 1;
if (confirmations <= 0) { confirmations = 1; }
receipt.confirmations = confirmations;
}
return receipt;
}, { oncePoll: this });
}
async getLogs(filter: Filter | FilterByBlockHash | Promise<Filter | FilterByBlockHash>): Promise<Array<Log>> {
await this.getNetwork();
const params = await resolveProperties({ filter: this._getFilter(filter) });
const logs: Array<Log> = await this.perform("getLogs", params);
logs.forEach((log) => {
if (log.removed == null) { log.removed = false; }
});
return Formatter.arrayOf(this.formatter.filterLog.bind(this.formatter))(logs);
}
async getEtherPrice(): Promise<number> {
await this.getNetwork();
return this.perform("getEtherPrice", { });
}
async _getBlockTag(blockTag: BlockTag | Promise<BlockTag>): Promise<BlockTag> {
blockTag = await blockTag;
if (typeof(blockTag) === "number" && blockTag < 0) {
if (blockTag % 1) {
logger.throwArgumentError("invalid BlockTag", "blockTag", blockTag);
}
let blockNumber = await this._getInternalBlockNumber(100 + 2 * this.pollingInterval);
blockNumber += blockTag;
if (blockNumber < 0) { blockNumber = 0; }
return this.formatter.blockTag(blockNumber)
}
return this.formatter.blockTag(blockTag);
}
async getResolver(name: string): Promise<null | Resolver> {
let currentName = name;
while (true) {
if (currentName === "" || currentName === ".") { return null; }
// Optimization since the eth node cannot change and does
// not have a wildcar resolver
if (name !== "eth" && currentName === "eth") { return null; }
// Check the current node for a resolver
const addr = await this._getResolver(currentName, "getResolver");
// Found a resolver!
if (addr != null) {
const resolver = new Resolver(this, addr, name);
// Legacy resolver found, using EIP-2544 so it isn't safe to use
if (currentName !== name && !(await resolver.supportsWildcard())) { return null; }
return resolver;
}
// Get the parent node
currentName = currentName.split(".").slice(1).join(".");
}
}
async _getResolver(name: string, operation?: string): Promise<string> {
if (operation == null) { operation = "ENS"; }
const network = await this.getNetwork();
// No ENS...
if (!network.ensAddress) {
logger.throwError(
"network does not support ENS",
Logger.errors.UNSUPPORTED_OPERATION,
{ operation, network: network.name }
);
}
try {
// keccak256("resolver(bytes32)")
const addrData = await this.call({
to: network.ensAddress,
data: ("0x0178b8bf" + namehash(name).substring(2))
});
return this.formatter.callAddress(addrData);
} catch (error) {
// ENS registry cannot throw errors on resolver(bytes32)
}
return null;
}
async resolveName(name: string | Promise<string>): Promise<null | string> {
name = await name;
// If it is already an address, nothing to resolve
try {
return Promise.resolve(this.formatter.address(name));
} catch (error) {
// If is is a hexstring, the address is bad (See #694)
if (isHexString(name)) { throw error; }
}
if (typeof(name) !== "string") {
logger.throwArgumentError("invalid ENS name", "name", name);
}
// Get the addr from the resovler
const resolver = await this.getResolver(name);
if (!resolver) { return null; }
return await resolver.getAddress();
}
async lookupAddress(address: string | Promise<string>): Promise<null | string> {
address = await address;
address = this.formatter.address(address);
const node = address.substring(2).toLowerCase() + ".addr.reverse";
const resolverAddr = await this._getResolver(node, "lookupAddress");
if (resolverAddr == null) { return null; }
// keccak("name(bytes32)")
const name = _parseString(await this.call({
to: resolverAddr,
data: ("0x691f3431" + namehash(node).substring(2))
}), 0);
const addr = await this.resolveName(name);
if (addr != address) { return null; }
return name;
}
async getAvatar(nameOrAddress: string): Promise<null | string> {
let resolver: Resolver = null;
if (isHexString(nameOrAddress)) {
// Address; reverse lookup
const address = this.formatter.address(nameOrAddress);
const node = address.substring(2).toLowerCase() + ".addr.reverse";
const resolverAddress = await this._getResolver(node, "getAvatar");
if (!resolverAddress) { return null; }
// Try resolving the avatar against the addr.reverse resolver
resolver = new Resolver(this, resolverAddress, node);
try {
const avatar = await resolver.getAvatar();
if (avatar) { return avatar.url; }
} catch (error) {
if (error.code !== Logger.errors.CALL_EXCEPTION) { throw error; }
}
// Try getting the name and performing forward lookup; allowing wildcards
try {
// keccak("name(bytes32)")
const name = _parseString(await this.call({
to: resolverAddress,
data: ("0x691f3431" + namehash(node).substring(2))
}), 0);
resolver = await this.getResolver(name);
} catch (error) {
if (error.code !== Logger.errors.CALL_EXCEPTION) { throw error; }
return null;
}
} else {
// ENS name; forward lookup with wildcard
resolver = await this.getResolver(nameOrAddress);
if (!resolver) { return null; }
}
const avatar = await resolver.getAvatar();
if (avatar == null) { return null; }
return avatar.url;
}
perform(method: string, params: any): Promise<any> {
return logger.throwError(method + " not implemented", Logger.errors.NOT_IMPLEMENTED, { operation: method });
}
_startEvent(event: Event): void {
this.polling = (this._events.filter((e) => e.pollable()).length > 0);
}
_stopEvent(event: Event): void {
this.polling = (this._events.filter((e) => e.pollable()).length > 0);
}
_addEventListener(eventName: EventType, listener: Listener, once: boolean): this {
const event = new Event(getEventTag(eventName), listener, once)
this._events.push(event);
this._startEvent(event);
return this;
}
on(eventName: EventType, listener: Listener): this {
return this._addEventListener(eventName, listener, false);
}
once(eventName: EventType, listener: Listener): this {
return this._addEventListener(eventName, listener, true);
}
emit(eventName: EventType, ...args: Array<any>): boolean {
let result = false;
let stopped: Array<Event> = [ ];
let eventTag = getEventTag(eventName);
this._events = this._events.filter((event) => {
if (event.tag !== eventTag) { return true; }
setTimeout(() => {
event.listener.apply(this, args);
}, 0);
result = true;
if (event.once) {
stopped.push(event);
return false;
}
return true;
});
stopped.forEach((event) => { this._stopEvent(event); });
return result;
}
listenerCount(eventName?: EventType): number {
if (!eventName) { return this._events.length; }
let eventTag = getEventTag(eventName);
return this._events.filter((event) => {
return (event.tag === eventTag);
}).length;
}
listeners(eventName?: EventType): Array<Listener> {
if (eventName == null) {
return this._events.map((event) => event.listener);
}
let eventTag = getEventTag(eventName);
return this._events
.filter((event) => (event.tag === eventTag))
.map((event) => event.listener);
}
off(eventName: EventType, listener?: Listener): this {
if (listener == null) {
return this.removeAllListeners(eventName);
}
const stopped: Array<Event> = [ ];
let found = false;
let eventTag = getEventTag(eventName);
this._events = this._events.filter((event) => {
if (event.tag !== eventTag || event.listener != listener) { return true; }
if (found) { return true; }
found = true;
stopped.push(event);
return false;
});
stopped.forEach((event) => { this._stopEvent(event); });
return this;
}
removeAllListeners(eventName?: EventType): this {
let stopped: Array<Event> = [ ];
if (eventName == null) {
stopped = this._events;
this._events = [ ];
} else {
const eventTag = getEventTag(eventName);
this._events = this._events.filter((event) => {
if (event.tag !== eventTag) { return true; }
stopped.push(event);
return false;
});
}
stopped.forEach((event) => { this._stopEvent(event); });
return this;
}
}