Send and Receive HTTP Messages
This example shows how to send a request to a server that involves redirection and might require digest authentication.
sendRequest function automatically redirects and
authenticates on the first request. For subsequent requests, you do not want to pay
the cost of a redirect. To do this,
sendRequest saves the cookies
received on previous requests and reuses them for subsequent requests.
sendRequest illustrates the use of the history, the reuse of a
HTTPOptions object to change the default timeout, and the use
of saved credentials.
This example does not illustrate a robust, general-purpose mechanism for achieving
these results. In particular,
sendRequest returns all cookies
received from a host in every subsequent message to that host, regardless of the
domain, path, expiration, or other properties.
does not save credentials or cookies across MATLAB® sessions. Nonetheless,
sendRequest is adequate for
sendRequest function from the following
function response = sendRequest(uri,request) % uri: matlab.net.URI % request: matlab.net.http.RequestMessage % response: matlab.net.http.ResponseMessage % matlab.net.http.HTTPOptions persists across requests to reuse previous % Credentials in it for subsequent authentications persistent options % infos is a containers.Map object where: % key is uri.Host; % value is "info" struct containing: % cookies: vector of matlab.net.http.Cookie or empty % uri: target matlab.net.URI if redirect, or empty persistent infos if isempty(options) options = matlab.net.http.HTTPOptions('ConnectTimeout',20); end if isempty(infos) infos = containers.Map; end host = string(uri.Host); % get Host from URI try % get info struct for host in map info = infos(host); if ~isempty(info.uri) % If it has a uri field, it means a redirect previously % took place, so replace requested URI with redirect URI. uri = info.uri; end if ~isempty(info.cookies) % If it has cookies, it means we previously received cookies from this host. % Add Cookie header field containing all of them. request = request.addFields(matlab.net.http.field.CookieField(info.cookies)); end catch % no previous redirect or cookies for this host info = ; end % Send request and get response and history of transaction. [response, ~, history] = request.send(uri, options); if response.StatusCode ~= matlab.net.http.StatusCode.OK return end % Get the Set-Cookie header fields from response message in % each history record and save them in the map. arrayfun(@addCookies, history) % If the last URI in the history is different from the URI sent in the original % request, then this was a redirect. Save the new target URI in the host info struct. targetURI = history(end).URI; if ~isequal(targetURI, uri) if isempty(info) % no previous info for this host in map, create new one infos(char(host)) = struct('cookies',,'uri',targetURI); else % change URI in info for this host and put it back in map info.uri = targetURI; infos(char(host)) = info; end end function addCookies(record) % Add cookies in Response message in history record % to the map entry for the host to which the request was directed. % ahost = record.URI.Host; % the host the request was sent to cookieFields = record.Response.getFields('Set-Cookie'); if isempty(cookieFields) return end cookieData = cookieFields.convert(); % get array of Set-Cookie structs cookies = [cookieData.Cookie]; % get array of Cookies from all structs try % If info for this host was already in the map, add its cookies to it. ainfo = infos(ahost); ainfo.cookies = [ainfo.cookies cookies]; infos(char(ahost)) = ainfo; catch % Not yet in map, so add new info struct. infos(char(ahost)) = struct('cookies',cookies,'uri',); end end end
Call the function.
request = matlab.net.http.RequestMessage; uri = matlab.net.URI('https://www.mathworks.com/products'); response = sendRequest(uri,request)
response = ResponseMessage with properties: StatusLine: 'HTTP/1.1 200 OK' StatusCode: OK Header: [1×11 matlab.net.http.HeaderField] Body: [1×1 matlab.net.http.MessageBody] Completed: 0
Your response values might be different.