[Help] Rest API programming.

[shonay]

Okay hi and good evening ,

Earlier on I was on Mobile so chances of coming on the computer was limited, hence i decided to  come online and write on here as i have the time here.
Now am trying to simulate a simple HTTP Request with Wininet i wanted to be sure of what I am Doing hence i decided to come up with a source code , I didnt fill other parameters because i wanted to see how it would be placed when Simulating(Sincerely pardon me as this is my first time Handling something like this)

Code goes like this

Code: Pascal  [Select][+][-]

1. program Project1;
2.  
3. {$mode delphi}{$H+}
4.  
5. uses
6.   {$IFDEF UNIX}{$IFDEF UseCThreads}
7.   cthreads,
8.   {$ENDIF}{$ENDIF}
9.   Classes , Wininet , Windows
10.   { you can add units after this };
11.  
12. procedure PostData()
13. var
14.   hInet: HINTERNET;
15.   hHTTP: HINTERNET;
16.   hReq: HINTERNET;
17.   const
18.     accept: packed array[0..1] of LPWSTR = (PChar('*/*'), nil);
19.     header: string = 'Content-Type: application/x-www-form-urlencoded';
20. begin
21.   hInet := InternetOpen(PChar(UserAgent), INTERNET_OPEN_TYPE_PRECONFIG, nil, nil, 0);
22.      hHTTP := InternetConnect(hInet, PChar(Server), INTERNET_DEFAULT_HTTP_PORT, nil, nil, INTERNET_SERVICE_HTTP, 0, 1);
23.       hReq := HttpOpenRequest(hHTTP, PChar('POST'), PChar(Resource), nil, nil, @accept, 0, 1);
24.       if not HttpSendRequest(hReq, PChar(header), length(header), PChar(Data), length(Data)) then
25.       raise Exception.Create('HttpOpenRequest failed. ' + SysErrorMessage(GetLastError));
26.       InternetCloseHandle(hReq);
27.       InternetCloseHandle(hHTTP);
28.       InternetCloseHandle(hInet);
29. end
30.  
31.  
32. begin
33. end.
34.  
35.  

Now In the case of the parameters i used Live HTTP Headers to retrieve the headers as well so i got this

Code: Pascal  [Select][+][-]

1. https://perfectmoney.is/api/step1.asp
2.  
3. POST /api/step1.asp HTTP/1.1
4. Host: perfectmoney.is
5. User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:41.0) Gecko/20100101 Firefox/41.0
6. Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
7. Accept-Language: en-US,en;q=0.5
8. Accept-Encoding: gzip, deflate
9. Referer: https://perfectmoney.is/api/pay.asp?acc=&cur=&name=&email=&memo=&pid=&ref=https%3A%2F%2Fperfectmoney.is&amount=250&action=Make+payment
10. Cookie: details=1366x768; data=289775471; pmc=b76ede0e957fd5ca7e6b03beb9949234; PM_SESSION=9e58e6742c8adebcb8c1ab00a2026e7603ed02108b9858797427819ce93efe91d4fa0a74
11. Connection: keep-alive
12. Content-Type: application/x-www-form-urlencoded
13. Content-Length: 257
14. PAYEE_ACCOUNT=&PAYEE_NAME=&PAYMENT_UNITS=&STATUS_URL=mailto%3A&PAYMENT_URL=https%253A%252F%252Fperfectmoney.is&PAYMENT_URL_METHOD=LINK&NOPAYMENT_URL=https%253A%252F%252Fperfectmoney.is&NOPAYMENT_URL_METHOD=LINK&SUGGESTED_MEMO=&PAYMENT_ID=&PAYMENT_AMOUNT=250
15.  
16.  

Now Good sir, How do I place the Values and do this in Pascal? suppose this was C / C++ I could have tried something , but i really would like to do this in Pascal, kindly help.

Help would be much much appreciated

[rvk]

First of all your code does absolutly nothing. You just have a "begin end".

Secondly... how did you come by https://perfectmoney.is/api/step1.asp ?

If I look at the documentation you could use https://perfectmoney.is/acct/verify.asp or https://perfectmoney.is/acct/confirm.asp.

I'm not that familiar with wininet myself but I'll show you some code using Synapse:

Code: Pascal  [Select][+][-]

1. procedure TForm1.btVerifyClick(Sender: TObject);
2. var
3.   HTTP: THTTPSend;
4.   Url: string;
5.   UrlData: string;
6.   Data: TMemoryStream;
7. begin
8.   if (edAccountID.Text = '') or (edPassPhrase.Text = '') or
9.     (edPayer.Text = '') or (edPayee.Text = '') or (edAmount.Text = '') or
10.     (edMemo.Text = '') then
11.   begin
12.     ShowMessage('Please fill out the fields with *');
13.     exit;
14.   end;
15.  
16.   UrlData := 'AccountID=' + edAccountID.Text;
17.   UrlData += '&PassPhrase=' + edPassPhrase.Text;
18.   UrlData += '&Payer_Account=' + edPayer.Text;
19.   UrlData += '&Payee_Account=' + edPayee.Text;
20.   UrlData += '&Amount=' + edAmount.Text;
21.   UrlData += '&Memo=' + edMemo.Text;
22.   if edPaymentID.Text <> '' then
23.     UrlData += '&PAYMENT_ID=' + edPaymentID.Text;
24.   if edcode.Text <> '' then
25.     UrlData += '&code=' + edcode.Text;
26.   if edperiod.Text <> '' then
27.     UrlData += '&period=' + edperiod.Text;
28.  
29.   Url := 'https://perfectmoney.is/acct/verify.asp';
30.  
31.   Data := TMemoryStream.Create;
32.   try
33.     if HttpPostURL(Url, UrlData, Data) then
34.     begin
35.       Data.Position := 0;
36.       memoResult.Lines.LoadFromStream(Data);
37.     end;
38.   finally
39.     Data.Free;
40.   end;
41.  
42. end;

This should works to send an amount from one account to another.
(use verify.asp to check if everything is ok and confirm.asp to actually send the money)

You'll need to fill in an AccountID, passphrase belonging to that id, payer to which account and payee from which account and the amount.

[shonay]

Grateful Sir, Synapse Works on Lazarus Pascal?

[eny]

Grateful Sir, Synapse Works on Lazarus Pascal?

  http://wiki.freepascal.org/Synapse

[shonay]

Many thanks @rvk, @thaddy @eny and even everyone who talked on this topic yesterday.

Now I want to install synapse. Do I just find the .pas file and include in my project? I have never used synapse before. Please how do I go about the installation

[Leledumbo]

Many thanks @rvk, @thaddy @eny and even everyone who talked on this topic yesterday.

Now I want to install synapse. Do I just find the .pas file and include in my project? I have never used synapse before. Please how do I go about the installation

Read, read, read and read: http://synapse.ararat.cz/doku.php/public:howto:installsynapse

[rvk]

Now I want to install synapse. Do I just find the .pas file and include in my project? I have never used synapse before. Please how do I go about the installation

Read, read, read and read: http://synapse.ararat.cz/doku.php/public:howto:installsynapse

@Leledumbo, to be fair... the method on that page doesn't seem to be working anymore (for me at least). (And I'm talking about the directory method because I can't imagine all the synapse files in your own project directory)

There is no "Aditional source search path for all projects" option anymore in the global Codetools options.
(Am I seeing that wrong or is that option completely removed?)

Secondly... adding the synapse directory to the Library path of your project also doesn't work because you'll get an error that you need to use the laz_synapse.lpk package.

Fatal: Cannot find ssl_openssl used by Unit1. Check if package laz_synapse is in the dependencies of the Project Inspector.

Here is how I normally do it:

• Download Synapse. I normally advice using the svn version. You can download it on this page. You can use the Download Snapshot button on that page.
• Extract it to a logical-named and placed directory.
• Now you need to add laz_synapse.lpk package to your project as a requirement:
  
  • Package > Open Package File > browse to the synapse directory
  • Choose laz_synapse.lpk
  • Now here is an extra step I always do if I need ssl_openssl
    If ssl_openssl.pas is not yet in the laz_synapse.lpk:
    
    • choose Add > Add Files from Filesystem
    • Choose ssl_openssl.pas
  • Choose Use >> Add to Project (and close the Package window)
• Now you can add httpsend, ssl_openssl and any other synapse unit you might need to your uses clause.

[shonay]

Thanks boss RVK

Lemme do it and get back to you this evening.
Many thanks again.

[rvk]

I fiddled some with the options and you could also get away with just adding the source-directory of synapse to the "Other unit files" in your project options. That initially didn't work for me because I still had a loaded laz_synapse in my IDE but after resetting this all it worked.

So it's not adding the directory to the library path but to the "Other unit files" which works too.

[shonay]

Good evening

I have a pressing issue now.
I have downloaded and extracted Synapse. I tried running the code and it tells me

Code: [Select]

ssl_openssl.pas(95,3) Fatal: Can not find unit blcksock used by ssl_openssl.

But i have the .pas file installed .

What could be wrong?
My source Code looks like this Now

Code: Pascal  [Select][+][-]

1. unit pmstore;
2.  
3. {$mode delphi}{$H+}
4.  
5. interface
6.  
7. uses
8.   Classes, SysUtils, FileUtil, Forms, Controls, Graphics, Dialogs, StdCtrls,
9.   ssl_openssl, httpsend;
10.  
11. type
12.  
13.   { TForm1 }
14.  
15.   TForm1 = class(TForm)
16.     Button1: TButton;
17.     Button2: TButton;
18.     Edit1: TEdit;
19.     Edit2: TEdit;
20.     Edit3: TEdit;
21.     Edit4: TEdit;
22.     Label1: TLabel;
23.     Label2: TLabel;
24.     Label3: TLabel;
25.     Label4: TLabel;
26.     procedure Button1Click(Sender: TObject);
27.     procedure Edit1Change(Sender: TObject);
28.   private
29.     { private declarations }
30.   public
31.     { public declarations }
32.   end;
33.  
34. var
35.   Form1: TForm1;
36.  
37. implementation
38.  
39. {$R *.lfm}
40.  
41. { TForm1 }
42.  
43. procedure TForm1.Button1Click(Sender: TObject);
44. var
45.     HTTP: THTTPSend;
46.     Url: string;
47.     UrlData: string;
48.     Data: TMemoryStream;
49. begin
50. UrlData := 'PAYEE_ACCOUNT=' + Edit1.Text;
51. UrlData := 'PAYEE_NAME=' + Edit2.Text;
52. UrlData := 'PAYMENT_UNITS=' + Edit3.Text;
53. UrlData := ' PAYMENT_AMOUNT=' + Edit4.Text;
54.  
55. Url := 'https://perfectmoney.is/acct/confirm.asp';
56.  
57. Data := TMemoryStream.Create;
58.  try
59.         if HttpPostURL(Url, UrlData, Data) then
60.         begin
61.         Data.Position := 0;
62.         //dont have an idea on how to send
63.         end;
64.         finally
65.           Data.Free
66.                 end;
67. end;
68.  
69. end.
70.  
71.  

Seems it has to be about the translation from Delphi to Lazarus? or what?

[rvk]

How did you include synapse in your project?
Did you add the laz_synapse package to your project or added the synapse directory to the "Other unit files" in your project options?

Also noticed a small problem with your code which you will run into later:

Code: Pascal  [Select][+][-]

1. UrlData := 'PAYEE_ACCOUNT=' + Edit1.Text;
2. UrlData := 'PAYEE_NAME=' + Edit2.Text;
3. UrlData := 'PAYMENT_UNITS=' + Edit3.Text;
4. UrlData := ' PAYMENT_AMOUNT=' + Edit4.Text;

This just overwrites UrlData on each line.
You want to add all those data together on one line separated by &-sign.
(notice I uses += in my code to add a string to UrlData)

[shonay]

How did you include synapse in your project?
Did you add the laz_synapse package to your project or added the synapse directory to the "Other unit files" in your project options?

Also noticed a small problem with your code which you will run into later:

Code: Pascal  [Select][+][-]

1. UrlData := 'PAYEE_ACCOUNT=' + Edit1.Text;
2. UrlData := 'PAYEE_NAME=' + Edit2.Text;
3. UrlData := 'PAYMENT_UNITS=' + Edit3.Text;
4. UrlData := ' PAYMENT_AMOUNT=' + Edit4.Text;

This just overwrites UrlData on each line.
You want to add all those data together on one line separated by &-sign.
(notice I uses += in my code to add a string to UrlData)

I didnt see the second option you gave. hence i didnt use the other unit files. i just added that laz_synapse.lpk and it threw that error.
I'm using Lazarus 1.2.6

concerning the UrlData, how do i fix that?

[rvk]

I didnt see the second option you gave. hence i didnt use the other unit files. i just added that laz_synapse.lpk and it threw that error.
I'm using Lazarus 1.2.6

1.2.6? That one is quite old. Why are you using such an old version?
You could remove laz_synapse as requirement and add the synapse directory to the "Other unit files" in your project options>Paths.

concerning the UrlData, how do i fix that?

Well, use my exact example

I would also use verify.asp instead of confirm.asp in your testing phase. In that case you get the exact same result but no funds are transferred away from your account.

[shonay]

I didnt see the second option you gave. hence i didnt use the other unit files. i just added that laz_synapse.lpk and it threw that error.
I'm using Lazarus 1.2.6

1.2.6? That one is quite old. Why are you using such an old version?
You could remove laz_synapse as requirement and add the synapse directory to the "Other unit files" in your project options>Paths.

concerning the UrlData, how do i fix that?

Well, use my exact example

I would also use verify.asp instead of confirm.asp in your testing phase. In that case you get the exact same result but no funds are transferred away from your account.

Seems you dont get this same issues , which version of Lazarus are u using Sir, hence I think i have to switch

[rvk]

Seems you dont get this same issues , which version of Lazarus are u using Sir, hence I think i have to switch

I use Lazarus development version (trunk) and Lazarus 1.4.4 for testing.

Lazarus 1.4.4 (the latest downloadable stable version) will work fine for you.