ethers.js/utils/web.js
2018-07-14 17:21:32 -04:00

174 lines
5.8 KiB
JavaScript

'use strict';
var __importStar = (this && this.__importStar) || function (mod) {
if (mod && mod.__esModule) return mod;
var result = {};
if (mod != null) for (var k in mod) if (Object.hasOwnProperty.call(mod, k)) result[k] = mod[k];
result["default"] = mod;
return result;
};
Object.defineProperty(exports, "__esModule", { value: true });
var xmlhttprequest_1 = require("xmlhttprequest");
var base64_1 = require("./base64");
var utf8_1 = require("./utf8");
var errors = __importStar(require("./errors"));
function fetchJson(connection, json, processFunc) {
var headers = [];
var url = null;
if (typeof (connection) === 'string') {
url = connection;
}
else if (typeof (connection) === 'object') {
if (connection.url == null) {
errors.throwError('missing URL', errors.MISSING_ARGUMENT, { arg: 'url' });
}
url = connection.url;
if (connection.user != null && connection.password != null) {
if (url.substring(0, 6) !== 'https:' && connection.allowInsecure !== true) {
errors.throwError('basic authentication requires a secure https url', errors.INVALID_ARGUMENT, { arg: 'url', url: url, user: connection.user, password: '[REDACTED]' });
}
var authorization = connection.user + ':' + connection.password;
headers.push({
key: 'Authorization',
value: 'Basic ' + base64_1.encode(utf8_1.toUtf8Bytes(authorization))
});
}
}
return new Promise(function (resolve, reject) {
var request = new xmlhttprequest_1.XMLHttpRequest();
if (json) {
request.open('POST', url, true);
headers.push({ key: 'Content-Type', value: 'application/json' });
}
else {
request.open('GET', url, true);
}
headers.forEach(function (header) {
request.setRequestHeader(header.key, header.value);
});
request.onreadystatechange = function () {
if (request.readyState !== 4) {
return;
}
try {
var result = JSON.parse(request.responseText);
}
catch (error) {
// @TODO: not any!
var jsonError = new Error('invalid json response');
jsonError.orginialError = error;
jsonError.responseText = request.responseText;
jsonError.url = url;
reject(jsonError);
return;
}
if (processFunc) {
try {
result = processFunc(result);
}
catch (error) {
error.url = url;
error.body = json;
error.responseText = request.responseText;
reject(error);
return;
}
}
if (request.status != 200) {
// @TODO: not any!
var error = new Error('invalid response - ' + request.status);
error.statusCode = request.status;
reject(error);
return;
}
resolve(result);
};
request.onerror = function (error) {
reject(error);
};
try {
if (json) {
request.send(json);
}
else {
request.send();
}
}
catch (error) {
// @TODO: not any!
var connectionError = new Error('connection error');
connectionError.error = error;
reject(connectionError);
}
});
}
exports.fetchJson = fetchJson;
function poll(func, options) {
if (!options) {
options = {};
}
if (options.floor == null) {
options.floor = 0;
}
if (options.ceiling == null) {
options.ceiling = 10000;
}
if (options.interval == null) {
options.interval = 250;
}
return new Promise(function (resolve, reject) {
var timer = null;
var done = false;
// Returns true if cancel was successful. Unsuccessful cancel means we're already done.
var cancel = function () {
if (done) {
return false;
}
done = true;
if (timer) {
clearTimeout(timer);
}
return true;
};
if (options.timeout) {
timer = setTimeout(function () {
if (cancel()) {
reject(new Error('timeout'));
}
}, options.timeout);
}
var attempt = 0;
function check() {
return func().then(function (result) {
// If we have a result, or are allowed null then we're done
if (result !== undefined) {
if (cancel()) {
resolve(result);
}
}
else if (options.onceBlock) {
options.onceBlock.once('block', check);
// Otherwise, exponential back-off (up to 10s) our next request
}
else if (!done) {
attempt++;
var timeout = options.interval * parseInt(String(Math.random() * Math.pow(2, attempt)));
if (timeout < options.floor) {
timeout = options.floor;
}
if (timeout > options.ceiling) {
timeout = options.ceiling;
}
setTimeout(check, timeout);
}
return null;
}, function (error) {
if (cancel()) {
reject(error);
}
});
}
check();
});
}
exports.poll = poll;