PullData.m

% 
% Function:     PullData 
% Author:       Michael T. Ballard (michael.ballard@uconn.edu)   
% Date:         Spring 2019  
% 
% Description:  The PullData function opens a TCP connection to the
%               specified host and places a query to the database designed for the
%               HuskyTrack System.  The response to this query is then collected and
%               stored for further manipulations and analysis.  Note that
%               time is always considered to be 12:00 AM Midnight, thus the
%               end date is exclusive.
% 
% Parameters:   url         - A URL to access the host database's API from
%                             ie. 'http://sdp40.cse.uconn.edu/api/'
%               startTime   - A time stamp to indicate the earliest desired
%                             data.  In the form 'YYYYMMDD', ie. 20190503
%                             (May 3, 2019)
%               endTime     - A time stamp to indicate the latest desired
%                             data.  In the form 'YYYYMMDD', ie. 20190503
%                             (May 3, 2019)
% 
% Return:       dataMat     - A struct containing all users and their
%                             location data retrieved from the host
%

function [dataMat] = PullData(url, startTime, endTime)

api = [url 'locationdata?start=' startTime 'T000000&end=' endTime 'T000000'];
options = weboptions('ContentType', 'json');
data = webread(api);
dataMat = jsondecode(data);

end