import { assert } from '@0xproject/assert';
import { schemas } from '@0xproject/json-schemas';
import 'isomorphic-fetch';
import * as _ from 'lodash';
import * as queryString from 'query-string';
import { schemas as clientSchemas } from './schemas/schemas';
import {
Client,
FeesRequest,
FeesResponse,
HttpRequestOptions,
HttpRequestType,
OrderbookRequest,
OrderbookResponse,
OrdersRequestOpts,
PagedRequestOpts,
SignedOrder,
TokenPairsItem,
TokenPairsRequestOpts,
} from './types';
import { relayerResponseJsonParsers } from './utils/relayer_response_json_parsers';
const TRAILING_SLASHES_REGEX = /\/+$/;
const DEFAULT_PAGED_REQUEST_OPTS: PagedRequestOpts = {
page: 1,
perPage: 100,
};
/**
* This mapping defines how an option property name gets converted into an HTTP request query field
*/
const OPTS_TO_QUERY_FIELD_MAP = {
perPage: 'per_page',
};
/**
* This class includes all the functionality related to interacting with a set of HTTP endpoints
* that implement the standard relayer API v0
*/
export class HttpClient implements Client {
private _apiEndpointUrl: string;
/**
* Format parameters to be appended to http requests into query string form
*/
private static _buildQueryStringFromHttpParams(params?: object): string {
// if params are undefined or empty, return an empty string
if (_.isUndefined(params) || _.isEmpty(params)) {
return '';
}
// format params into a form the api expects
const formattedParams = _.mapKeys(params, (value: any, key: string) => {
return _.get(OPTS_TO_QUERY_FIELD_MAP, key, key);
});
// stringify the formatted object
const stringifiedParams = queryString.stringify(formattedParams);
return `?${stringifiedParams}`;
}
/**
* Instantiates a new HttpClient instance
* @param url The relayer API base HTTP url you would like to interact with
* @return An instance of HttpClient
*/
constructor(url: string) {
assert.isHttpUrl('url', url);
this._apiEndpointUrl = url.replace(TRAILING_SLASHES_REGEX, ''); // remove trailing slashes
}
/**
* Retrieve token pair info from the API
* @param requestOpts Options specifying token information to retrieve and page information, defaults to { page: 1, perPage: 100 }
* @return The resulting TokenPairsItems that match the request
*/
public async getTokenPairsAsync(requestOpts?: TokenPairsRequestOpts & PagedRequestOpts): Promise<TokenPairsItem[]> {
if (!_.isUndefined(requestOpts)) {
assert.doesConformToSchema('requestOpts', requestOpts, clientSchemas.tokenPairsRequestOptsSchema);
assert.doesConformToSchema('requestOpts', requestOpts, clientSchemas.pagedRequestOptsSchema);
}
const httpRequestOpts = {
params: _.defaults({}, requestOpts, DEFAULT_PAGED_REQUEST_OPTS),
};
const responseJson = await this._requestAsync('/token_pairs', HttpRequestType.Get, httpRequestOpts);
const tokenPairs = relayerResponseJsonParsers.parseTokenPairsJson(responseJson);
return tokenPairs;
}
/**
* Retrieve orders from the API
* @param requestOpts Options specifying orders to retrieve and page information, defaults to { page: 1, perPage: 100 }
* @return The resulting SignedOrders that match the request
*/
public async getOrdersAsync(requestOpts?: OrdersRequestOpts & PagedRequestOpts): Promise<SignedOrder[]> {
if (!_.isUndefined(requestOpts)) {
assert.doesConformToSchema('requestOpts', requestOpts, clientSchemas.ordersRequestOptsSchema);
assert.doesConformToSchema('requestOpts', requestOpts, clientSchemas.pagedRequestOptsSchema);
}
const httpRequestOpts = {
params: _.defaults({}, requestOpts, DEFAULT_PAGED_REQUEST_OPTS),
};
const responseJson = await this._requestAsync(`/orders`, HttpRequestType.Get, httpRequestOpts);
const orders = relayerResponseJsonParsers.parseOrdersJson(responseJson);
return orders;
}
/**
* Retrieve a specific order from the API
* @param orderHash An orderHash generated from the desired order
* @return The SignedOrder that matches the supplied orderHash
*/
public async getOrderAsync(orderHash: string): Promise<SignedOrder> {
assert.doesConformToSchema('orderHash', orderHash, schemas.orderHashSchema);
const responseJson = await this._requestAsync(`/order/${orderHash}`, HttpRequestType.Get);
const order = relayerResponseJsonParsers.parseOrderJson(responseJson);
return order;
}
/**
* Retrieve an orderbook from the API
* @param request An OrderbookRequest instance describing the specific orderbook to retrieve
* @param requestOpts Options specifying page information, defaults to { page: 1, perPage: 100 }
* @return The resulting OrderbookResponse that matches the request
*/
public async getOrderbookAsync(
request: OrderbookRequest,
requestOpts?: PagedRequestOpts,
): Promise<OrderbookResponse> {
assert.doesConformToSchema('request', request, clientSchemas.orderBookRequestSchema);
if (!_.isUndefined(requestOpts)) {
assert.doesConformToSchema('requestOpts', requestOpts, clientSchemas.pagedRequestOptsSchema);
}
const httpRequestOpts = {
params: _.defaults({}, request, requestOpts, DEFAULT_PAGED_REQUEST_OPTS),
};
const responseJson = await this._requestAsync('/orderbook', HttpRequestType.Get, httpRequestOpts);
const orderbook = relayerResponseJsonParsers.parseOrderbookResponseJson(responseJson);
return orderbook;
}
/**
* Retrieve fee information from the API
* @param request A FeesRequest instance describing the specific fees to retrieve
* @return The resulting FeesResponse that matches the request
*/
public async getFeesAsync(request: FeesRequest): Promise<FeesResponse> {
assert.doesConformToSchema('request', request, clientSchemas.feesRequestSchema);
const httpRequestOpts = {
payload: request,
};
const responseJson = await this._requestAsync('/fees', HttpRequestType.Post, httpRequestOpts);
const fees = relayerResponseJsonParsers.parseFeesResponseJson(responseJson);
return fees;
}
/**
* Submit a signed order to the API
* @param signedOrder A SignedOrder instance to submit
*/
public async submitOrderAsync(signedOrder: SignedOrder): Promise<void> {
assert.doesConformToSchema('signedOrder', signedOrder, schemas.signedOrderSchema);
const requestOpts = {
payload: signedOrder,
};
await this._requestAsync('/order', HttpRequestType.Post, requestOpts);
}
private async _requestAsync(
path: string,
requestType: HttpRequestType,
requestOptions?: HttpRequestOptions,
): Promise<any> {
const params = _.get(requestOptions, 'params');
const payload = _.get(requestOptions, 'payload');
const query = HttpClient._buildQueryStringFromHttpParams(params);
const url = `${this._apiEndpointUrl}${path}${query}`;
const headers = new Headers({
'content-type': 'application/json',
});
const response = await fetch(url, {
method: requestType,
body: JSON.stringify(payload),
headers,
});
const json = await response.json();
if (!response.ok) {
const errorString = `${response.status} - ${response.statusText}\n${requestType} ${url}\n${JSON.stringify(
json,
)}`;
throw Error(errorString);
}
return json;
}
}