Why does webread() fail to find my host?

I'm writing a script to scrape .csv file data from a webserver hosted on an ESP8266. The webserver works -- I can access the .csv data stored there through my web browser. When I try to scrape that data into MATLAB using the code below, webread() fails. Interestingly I can comment out one of the calls to webread() and the other will work. What gives?

The data is the UNIX timestamp and a temperature or distance measurement separated by a comma and delimited by newlines, if that's relevant. MATLAB reads it as a 1 x n char.

% to prevent matlab from erroring out during the webread, set up a while
% loop:
i = 1;
e = 0;
I = 100;
while i < I
    try 
        % specify the url of the .csv:
        urlT = 'http://esp8266.local/temp.csv';
        % read the contents of the url with matlab's webread:
        T = webread(urlT);
        % specify a new url and read it into a char array:
        urlD = 'http://esp8266.local/dist.csv';
        D = webread(urlD);
        i = i + 1;
        e = 0;
    catch
        fprintf("webread was unsuccessful; waiting to try again.\n");
        pause(0.5);
        e = e + 1;
        if e > 50
            keyboard
        end
    end
end

Answer 1

[Rohit Pappu]

webread() might not be able to process the CSV file, directed by the URL. A possible workaround could be

D = webread(url, 'table'); %% Explicitly mention that the url points to a CSV file

%% Alternatively, download the csv file into a filename
filename = 'dummy.csv';
D = websave(filename,url);

Additional documentation about websave()

[zach tyler]

Really interesting -- this is exactly the sort of functionality I was hoping for, but couldn't find initially (I'm a newbie). Thanks, I will give this a try.