aurelia-fetch-client/dist/es2015/aurelia-fetch-client.js

A simple client based on the Fetch standard.

import { PLATFORM, DOM } from 'aurelia-pal';

function json(body, replacer) {
    return JSON.stringify((body !== undefined ? body : {}), replacer);
}

const retryStrategy = {
    fixed: 0,
    incremental: 1,
    exponential: 2,
    random: 3
};
const defaultRetryConfig = {
    maxRetries: 3,
    interval: 1000,
    strategy: retryStrategy.fixed
};
class RetryInterceptor {
    constructor(retryConfig) {
        this.retryConfig = Object.assign({}, defaultRetryConfig, retryConfig || {});
        if (this.retryConfig.strategy === retryStrategy.exponential &&
            this.retryConfig.interval <= 1000) {
            throw new Error('An interval less than or equal to 1 second is not allowed when using the exponential retry strategy');
        }
    }
    request(request) {
        let $r = request;
        if (!$r.retryConfig) {
            $r.retryConfig = Object.assign({}, this.retryConfig);
            $r.retryConfig.counter = 0;
        }
        $r.retryConfig.requestClone = request.clone();
        return request;
    }
    response(response, request) {
        delete request.retryConfig;
        return response;
    }
    responseError(error, request, httpClient) {
        const { retryConfig } = request;
        const { requestClone } = retryConfig;
        return Promise.resolve().then(() => {
            if (retryConfig.counter < retryConfig.maxRetries) {
                const result = retryConfig.doRetry ? retryConfig.doRetry(error, request) : true;
                return Promise.resolve(result).then(doRetry => {
                    if (doRetry) {
                        retryConfig.counter++;
                        return new Promise(resolve => PLATFORM.global.setTimeout(resolve, calculateDelay(retryConfig) || 0))
                            .then(() => {
                            let newRequest = requestClone.clone();
                            if (typeof (retryConfig.beforeRetry) === 'function') {
                                return retryConfig.beforeRetry(newRequest, httpClient);
                            }
                            return newRequest;
                        })
                            .then(newRequest => {
                            return httpClient.fetch(Object.assign(newRequest, { retryConfig }));
                        });
                    }
                    delete request.retryConfig;
                    throw error;
                });
            }
            delete request.retryConfig;
            throw error;
        });
    }
}
function calculateDelay(retryConfig) {
    const { interval, strategy, minRandomInterval, maxRandomInterval, counter } = retryConfig;
    if (typeof (strategy) === 'function') {
        return retryConfig.strategy(counter);
    }
    switch (strategy) {
        case (retryStrategy.fixed):
            return retryStrategies[retryStrategy.fixed](interval);
        case (retryStrategy.incremental):
            return retryStrategies[retryStrategy.incremental](counter, interval);
        case (retryStrategy.exponential):
            return retryStrategies[retryStrategy.exponential](counter, interval);
        case (retryStrategy.random):
            return retryStrategies[retryStrategy.random](counter, interval, minRandomInterval, maxRandomInterval);
        default:
            throw new Error('Unrecognized retry strategy');
    }
}
const retryStrategies = [
    interval => interval,
    (retryCount, interval) => interval * retryCount,
    (retryCount, interval) => retryCount === 1 ? interval : Math.pow(interval, retryCount) / 1000,
    (retryCount, interval, minRandomInterval = 0, maxRandomInterval = 60000) => {
        return Math.random() * (maxRandomInterval - minRandomInterval) + minRandomInterval;
    }
];

class HttpClientConfiguration {
    constructor() {
        this.baseUrl = '';
        this.defaults = {};
        this.interceptors = [];
    }
    withBaseUrl(baseUrl) {
        this.baseUrl = baseUrl;
        return this;
    }
    withDefaults(defaults) {
        this.defaults = defaults;
        return this;
    }
    withInterceptor(interceptor) {
        this.interceptors.push(interceptor);
        return this;
    }
    useStandardConfiguration() {
        let standardConfig = { credentials: 'same-origin' };
        Object.assign(this.defaults, standardConfig, this.defaults);
        return this.rejectErrorResponses();
    }
    rejectErrorResponses() {
        return this.withInterceptor({ response: rejectOnError });
    }
    withRetry(config) {
        const interceptor = new RetryInterceptor(config);
        return this.withInterceptor(interceptor);
    }
}
function rejectOnError(response) {
    if (!response.ok) {
        throw response;
    }
    return response;
}

class HttpClient {
    constructor() {
        this.activeRequestCount = 0;
        this.isRequesting = false;
        this.isConfigured = false;
        this.baseUrl = '';
        this.defaults = null;
        this.interceptors = [];
        if (typeof fetch === 'undefined') {
            throw new Error('HttpClient requires a Fetch API implementation, but the current environment doesn\'t support it. You may need to load a polyfill such as https://github.com/github/fetch');
        }
    }
    configure(config) {
        let normalizedConfig;
        if (typeof config === 'object') {
            normalizedConfig = { defaults: config };
        }
        else if (typeof config === 'function') {
            normalizedConfig = new HttpClientConfiguration();
            normalizedConfig.baseUrl = this.baseUrl;
            normalizedConfig.defaults = Object.assign({}, this.defaults);
            normalizedConfig.interceptors = this.interceptors;
            let c = config(normalizedConfig);
            if (HttpClientConfiguration.prototype.isPrototypeOf(c)) {
                normalizedConfig = c;
            }
        }
        else {
            throw new Error('invalid config');
        }
        let defaults = normalizedConfig.defaults;
        if (defaults && Headers.prototype.isPrototypeOf(defaults.headers)) {
            throw new Error('Default headers must be a plain object.');
        }
        let interceptors = normalizedConfig.interceptors;
        if (interceptors && interceptors.length) {
            if (interceptors.filter(x => RetryInterceptor.prototype.isPrototypeOf(x)).length > 1) {
                throw new Error('Only one RetryInterceptor is allowed.');
            }
            const retryInterceptorIndex = interceptors.findIndex(x => RetryInterceptor.prototype.isPrototypeOf(x));
            if (retryInterceptorIndex >= 0 && retryInterceptorIndex !== interceptors.length - 1) {
                throw new Error('The retry interceptor must be the last interceptor defined.');
            }
        }
        this.baseUrl = normalizedConfig.baseUrl;
        this.defaults = defaults;
        this.interceptors = normalizedConfig.interceptors || [];
        this.isConfigured = true;
        return this;
    }
    fetch(input, init) {
        trackRequestStart(this);
        let request = this.buildRequest(input, init);
        return processRequest(request, this.interceptors, this).then(result => {
            let response = null;
            if (Response.prototype.isPrototypeOf(result)) {
                response = Promise.resolve(result);
            }
            else if (Request.prototype.isPrototypeOf(result)) {
                request = result;
                response = fetch(result);
            }
            else {
                throw new Error(`An invalid result was returned by the interceptor chain. Expected a Request or Response instance, but got [${result}]`);
            }
            return processResponse(response, this.interceptors, request, this);
        })
            .then(result => {
            if (Request.prototype.isPrototypeOf(result)) {
                return this.fetch(result);
            }
            return result;
        })
            .then(result => {
            trackRequestEnd(this);
            return result;
        }, error => {
            trackRequestEnd(this);
            throw error;
        });
    }
    buildRequest(input, init) {
        let defaults = this.defaults || {};
        let request;
        let body;
        let requestContentType;
        let parsedDefaultHeaders = parseHeaderValues(defaults.headers);
        if (Request.prototype.isPrototypeOf(input)) {
            request = input;
            requestContentType = new Headers(request.headers).get('Content-Type');
        }
        else {
            if (!init) {
                init = {};
            }
            body = init.body;
            let bodyObj = body ? { body } : null;
            let requestInit = Object.assign({}, defaults, { headers: {} }, init, bodyObj);
            requestContentType = new Headers(requestInit.headers).get('Content-Type');
            request = new Request(getRequestUrl(this.baseUrl, input), requestInit);
        }
        if (!requestContentType) {
            if (new Headers(parsedDefaultHeaders).has('content-type')) {
                request.headers.set('Content-Type', new Headers(parsedDefaultHeaders).get('content-type'));
            }
            else if (body && isJSON(body)) {
                request.headers.set('Content-Type', 'application/json');
            }
        }
        setDefaultHeaders(request.headers, parsedDefaultHeaders);
        if (body && Blob.prototype.isPrototypeOf(body) && body.type) {
            request.headers.set('Content-Type', body.type);
        }
        return request;
    }
    get(input, init) {
        return this.fetch(input, init);
    }
    post(input, body, init) {
        return callFetch(this, input, body, init, 'POST');
    }
    put(input, body, init) {
        return callFetch(this, input, body, init, 'PUT');
    }
    patch(input, body, init) {
        return callFetch(this, input, body, init, 'PATCH');
    }
    delete(input, body, init) {
        return callFetch(this, input, body, init, 'DELETE');
    }
}
const absoluteUrlRegexp = /^([a-z][a-z0-9+\-.]*:)?\/\//i;
function trackRequestStart(client) {
    client.isRequesting = !!(++client.activeRequestCount);
    if (client.isRequesting) {
        let evt = DOM.createCustomEvent('aurelia-fetch-client-request-started', { bubbles: true, cancelable: true });
        setTimeout(() => DOM.dispatchEvent(evt), 1);
    }
}
function trackRequestEnd(client) {
    client.isRequesting = !!(--client.activeRequestCount);
    if (!client.isRequesting) {
        let evt = DOM.createCustomEvent('aurelia-fetch-client-requests-drained', { bubbles: true, cancelable: true });
        setTimeout(() => DOM.dispatchEvent(evt), 1);
    }
}
function parseHeaderValues(headers) {
    let parsedHeaders = {};
    for (let name in headers || {}) {
        if (headers.hasOwnProperty(name)) {
            parsedHeaders[name] = (typeof headers[name] === 'function') ? headers[name]() : headers[name];
        }
    }
    return parsedHeaders;
}
function getRequestUrl(baseUrl, url) {
    if (absoluteUrlRegexp.test(url)) {
        return url;
    }
    return (baseUrl || '') + url;
}
function setDefaultHeaders(headers, defaultHeaders) {
    for (let name in defaultHeaders || {}) {
        if (defaultHeaders.hasOwnProperty(name) && !headers.has(name)) {
            headers.set(name, defaultHeaders[name]);
        }
    }
}
function processRequest(request, interceptors, http) {
    return applyInterceptors(request, interceptors, 'request', 'requestError', http);
}
function processResponse(response, interceptors, request, http) {
    return applyInterceptors(response, interceptors, 'response', 'responseError', request, http);
}
function applyInterceptors(input, interceptors, successName, errorName, ...interceptorArgs) {
    return (interceptors || [])
        .reduce((chain, interceptor) => {
        let successHandler = interceptor[successName];
        let errorHandler = interceptor[errorName];
        return chain.then(successHandler && (value => successHandler.call(interceptor, value, ...interceptorArgs)) || identity, errorHandler && (reason => errorHandler.call(interceptor, reason, ...interceptorArgs)) || thrower);
    }, Promise.resolve(input));
}
function isJSON(str) {
    try {
        JSON.parse(str);
    }
    catch (err) {
        return false;
    }
    return true;
}
function identity(x) {
    return x;
}
function thrower(x) {
    throw x;
}
function callFetch(client, input, body, init, method) {
    if (!init) {
        init = {};
    }
    init.method = method;
    if (body) {
        init.body = body;
    }
    return client.fetch(input, init);
}

export { json, retryStrategy, RetryInterceptor, HttpClientConfiguration, HttpClient };