topic Re: Proc http post method - passing parameters problem in SAS Programming

Proc http post method - passing parameters problem

HosSu — Thu, 02 Apr 2020 10:07:03 GMT

I am trying to write a proc http with post method in order to check login possibility to a website (SASCIStudio).

This is the code im using:

%let username=MyName;
%let pwd=password;
filename input TEMP;
filename resp TEMP;
filename headers TEMP;

/*
Macro that simply echoes the contents of a fileref to the SAS log
*/
%macro echofile(file);
data _null_;
infile &file;
input;
put _infile_;
run;
%mend;
/*
* Create the input file for the request
*/
data _null_;
 file input recfm=f lrecl=1;
 put "username=&username.%nrstr(&password)=&pwd";
run;

%echofile(input);

proc http
method="POST"
url="https://logon-website.com/security_check"
in=input
headerout=headers
out=resp;
run;

the echofile macro output:

username=MyName&password=password NOTE: 1 record was read from the infile INPUT.

The output form in the resp file:

<form id="fm1" class="form-stacked" onSubmit="return setSubmitUrl(this);" action="https://logon-website.com/security_check" method="post"> <fieldset> <legend>Sign In<sup>®</sup></legend> <div class="clearfix"> <label for="username"><span class="accesskey">U</span>ser ID:</label> <input id="username" name="username" class="required" tabindex="1" accesskey="u" type="text" value="" size="25" autocomplete="off"/> </div> <div class="clearfix"> <label for="password"><span class="accesskey">P</span>assword:</label> <input id="password" name="password" class="required" tabindex="2" accesskey="p" type="password" value="" size="25" autocomplete="off"/> </div> </fieldset> <input type="hidden" name="lt" value="LT-2117-BJYk9XdRaLUPCHpGyDvAC0sxNf6Vd7" /> <input type="hidden" name="execution" value="e1s1" /> <input type="hidden" name="_eventId" value="submit" /> <div class="submitb"><input id="Logon" type="submit" value="Sign In" onClick="this.disabled=true;this.form.submit();" tabindex="3" /></div> </form>

Values of username and password are missing in the output form.

There are no errors as I am getting 200 OK, but i am expecting 302 FOUND. I am using SAS9.4.

Is there a way to properly use the post method and check the login possibility when provided with valid credentials?

Re: Proc http post method - passing parameters problem

ChrisNZ — Fri, 03 Apr 2020 02:11:20 GMT

Have you tried setting the debug level to 1 or 2 to see what's being sent?

Re: Proc http post method - passing parameters problem

HosSu — Fri, 03 Apr 2020 06:26:55 GMT

Im afraid my SAS version does not allow it - i found that it is only available starting in SAS 9.4M5.

using this:

proc http
method="POST"
url="https://logon-website.com/security_check"
in=input
headerout=headers
out=resp;
debug level=2;
run;

causes an error:

ERROR 180-322: Statement is not valid or it is used out of proper order.

Is there any other way to see the request sent?

Re: Proc http post method - passing parameters problem

ChrisNZ — Fri, 03 Apr 2020 22:05:28 GMT

> Is there any other way to see the request sent?

Only 2 ways I can think of: connect to a web server you control, or use a packet analyzer such as wireshark,

Fyi, I ran this:

%let username=MyName;
%let pwd=MyPassword;
filename input TEMP;
filename resp TEMP;
filename headers TEMP;

data _null_;
 file input recfm=f lrecl=1;
 put "username=&username.%nrstr(&password)=&pwd";
run;

proc http
method="POST"
url="https://google.com"
in=input
headerout=headers
out=resp;
debug level=2;
run;

and got this:

100        method="POST"
 101        url="https://google.com"
 102        in=input
 103        headerout=headers
 104        out=resp;
 105        debug level=2;
 106        run;
 
 > POST / HTTP/1.1
 > User-Agent: SAS/9
 > Host: google.com
 > Accept: */*
 > Connection: Keep-Alive
 > Content-Length: 35
 > Content-Type: application/x-www-form-urlencoded
 > 
 > 00007F93DA73E260: 75 73 65 72 6E 61 6D 65 3D 4D 79 4E 61 6D 65 26 username=MyName&
 > 00007F93DA73E270: 70 61 73 73 77 6F 72 64 3D 4D 79 50 61 73 73 77 password=MyPassw
 > 00007F93DA73E280: 6F 72 64                                        ord             
 < HTTP/1.1 405 Method Not Allowed
 < Allow: GET, HEAD
 < Date: Fri, 03 Apr 2020 22:01:40 GMT
 < Content-Type: text/html; charset=UTF-8
 < Server: gws
 < Content-Length: 1589
 < X-XSS-Protection: 0
 < X-Frame-Options: SAMEORIGIN
 < Alt-Svc: quic=":443"; ma=2592000; v="46,43",h3-Q050=":443"; ma=2592000,h3-Q049=":443"; ma=2592000,h3-Q048=":443"; 
 ma=2592000,h3-Q046=":443"; ma=2592000,h3-Q043=":443"; ma=2592000,h3-T050=":443"; ma=2592000
 <