Posts Tagged ‘VB.NET’

OAuth 2.0 with Gmail over IMAP for installed applications

Monday, March 13th, 2017

OAuth is an open protocol to allow secure API authorization in a simple and standard method from desktop and web applications.

This article describes using OAuth 2.0 to access Gmail IMAP and SMTP servers using .NET IMAP component in installed applications scenario. You can also use OAuth 2.0 for web applications.

Google.Apis

Use Nuget to download “Google.Apis.Auth” package.

Import namespaces:

// c#

using Google.Apis.Auth.OAuth2;
using Google.Apis.Auth.OAuth2.Flows;
using Google.Apis.Auth.OAuth2.Requests;
using Google.Apis.Auth.OAuth2.Responses;

using Limilabs.Client.Authentication.Google;

using Limilabs.Client.IMAP;
' VB.NET 

Imports Google.Apis.Auth.OAuth2
Imports Google.Apis.Auth.OAuth2.Flows
Imports Google.Apis.Auth.OAuth2.Requests
Imports Google.Apis.Auth.OAuth2.Responses

Imports Limilabs.Client.Authentication.Google

Imports Limilabs.Client.IMAP

Register Application

Before you can use OAuth 2.0, you must register your application using the Google Developers Console.

At least product name must be specified:

Now create credentials:

After you’ve registered, copy the “Client ID” and “Client secret” values, which you’ll need later:

Now we can define clientID, clientSecret and scope variables, as well as Google OAuth 2.0 server addresses. Scope basically specifies what services we want to have access to. In our case it is user’s email address and IMAP/SMTP access:

// c#

string clientID = "XXX.apps.googleusercontent.com";
string clientSecret = "IxBs0g5sdaSDUz4Ea7Ix-Ua";

var clientSecrets = new ClientSecrets
{
    ClientId = clientID,
    ClientSecret = clientSecret
};

var credential = new GoogleAuthorizationCodeFlow(new GoogleAuthorizationCodeFlow.Initializer
{
    ClientSecrets = clientSecrets,
    Scopes = new[] { GoogleScope.ImapAndSmtp.Name, GoogleScope.EmailScope.Name}
});
' VB.NET 

Dim clientID As String = "XXX.apps.googleusercontent.com"
Dim clientSecret As String = "IxBs0g5sdaSDUz4Ea7Ix-Ua"

Dim clientSecrets = New ClientSecrets() With { _
	Key .ClientId = clientID, _
	Key .ClientSecret = clientSecret _
}

Dim credential = New GoogleAuthorizationCodeFlow(New GoogleAuthorizationCodeFlow.Initializer() With { _
	Key .ClientSecrets = clientSecrets, _
	Key .Scopes = New () {GoogleScope.ImapAndSmtp.Name, GoogleScope.EmailScope.Name} _
})

Turn on Google+ API

Remember to turn on Google+ API:
Turn on Google+ API

It is required to obtain email address of the user.

Obtain an OAuth 2.0 access token

Now we’ll create authorization url:


AuthorizationCodeRequestUrl url = credential.CreateAuthorizationCodeRequest("urn:ietf:wg:oauth:2.0:oob");

Process.Start(url.Build().ToString());
' VB.NET 

Dim url As AuthorizationCodeRequestUrl = credential.CreateAuthorizationCodeRequest("urn:ietf:wg:oauth:2.0:oob")

Process.Start(url.Build().ToString())

We are using Process.Start here, but you can also embed WebBrowser control in your application.

At this point user is redirected to Google to authorize the access:

After this step user is presented a code that needs to be pasted to your application:

Please note that this code also appears in the title of the browser:

  • It is possible to monitor processes on your machine and act automatically when it is there.
  • If you use embedded WebBrowser control in your application, you can monitor the HTML document title after any redirect.

Following is a code that reads this code and contacts Google to exchange it for a refresh-token and an access-token:

string authCode = Console.ReadLine();

TokenResponse token = await credential.ExchangeCodeForTokenAsync("", authCode, "urn:ietf:wg:oauth:2.0:oob", CancellationToken.None);

string accessToken = token.AccessToken;
' VB.NET 

Dim authCode As String = Console.ReadLine()

Dim token As TokenResponse = Await credential.ExchangeCodeForTokenAsync("", authCode, "urn:ietf:wg:oauth:2.0:oob", CancellationToken.None)

Dim accessToken As String = token.AccessToken

An access token is usually valid for a maximum of one hour, and allows you to access the user’s data. You also received a refresh token. A refresh token can be used to request a new access token once the previous expired.

Access IMAP/SMTP server

Finally we’ll ask Google for user’s email and use LoginOAUTH2 method to access Gmail’s IMAP server:

// c#

GoogleApi api = new GoogleApi(accessToken);
string user = api.GetEmailPlus();

using (Imap imap = new Imap())
{
    imap.ConnectSSL("imap.gmail.com");
    imap.LoginOAUTH2(user, accessToken);

    imap.SelectInbox();
    List<long> uids = imap.Search(Flag.Unseen);

    foreach (long uid in uids)
    {
        var eml = imap.GetMessageByUID(uid);
        IMail email = new MailBuilder().CreateFromEml(eml);
        Console.WriteLine(email.Subject);
    }
    imap.Close();
}
' VB.NET 

Dim api As New GoogleApi(accessToken)
Dim user As String = api.GetEmailPlus()

Using imap As New Imap()
	imap.ConnectSSL("imap.gmail.com")
	imap.LoginOAUTH2(user, accessToken)

	imap.SelectInbox()
	Dim uids As List(Of Long) = imap.Search(Flag.Unseen)

	For Each uid As Long In uids
		Dim eml = imap.GetMessageByUID(uid)
		Dim email As IMail = New MailBuilder().CreateFromEml(eml)
		Console.WriteLine(email.Subject)
	Next
	imap.Close()
End Using

Refreshing access token

An access token is usually short lived and valid for a maximum of one hour. The main reason behind this is security and prevention of replay attacks. This means that for long-lived applications you need to refresh the access token.

Your refresh token will be sent only once – don’t loose it!

We recommend storing entire TokenResponse object received from GoogleAuthorizationCodeFlow.ExchangeCodeForTokenAsync method call. This object contains both: refresh token and access token, along with its expiration time.

The process of refreshing access token is simple:

// c#

TokenResponse refreshed = await credential.RefreshTokenAsync("", token.RefreshToken, CancellationToken.None);

' VB.NET 

Dim refreshed As TokenResponse = Await credential.RefreshTokenAsync("", token.RefreshToken, CancellationToken.None)

OAuth 2.0 with Gmail over IMAP for web applications

Monday, March 13th, 2017

OAuth is an open protocol to allow secure API authorization in a simple and standard method from desktop and web applications.

This article describes using OAuth 2.0 to access Gmail IMAP and SMTP servers using .NET IMAP component in web application scenario (ASP.NET/ASP.NET MVC). You can also use OAuth 2.0 for installed applications.

Google.Apis

Use Nuget to download “Google.Apis.Auth” package.

Import namespaces:

// c#

using Google.Apis.Auth.OAuth2;
using Google.Apis.Auth.OAuth2.Flows;
using Google.Apis.Auth.OAuth2.Requests;
using Google.Apis.Auth.OAuth2.Responses;

using Limilabs.Client.Authentication.Google;

using Limilabs.Client.IMAP;
' VB.NET 

Imports Google.Apis.Auth.OAuth2
Imports Google.Apis.Auth.OAuth2.Flows
Imports Google.Apis.Auth.OAuth2.Requests
Imports Google.Apis.Auth.OAuth2.Responses

Imports Limilabs.Client.Authentication.Google

Imports Limilabs.Client.IMAP

Register Application

Before you can use OAuth 2.0, you must register your application using the Google Developers Console. After you’ve registered, go to the API Access tab and copy the “Client ID” and “Client secret” values and specify “Redirect URI“, which you’ll need later.

At least product name must be specified:

Now create credentials:

Specify redirect URI:

After you’ve registered, copy the “Client ID” and “Client secret” values, which you’ll need later:

Now we can define clientID, clientSecret, redirect url and scope variables, as well as Google OAuth 2.0 server addresses. Scope basically specifies what services we want to have access to. In our case it is user’s email address and IMAP/SMTP access:

// c#

string clientID = "XXX.apps.googleusercontent.com";
string clientSecret = "IxBs0g5sdaSDUz4Ea7Ix-Ua";
string redirectUri = "http://www.yourdomain.com/oauth2callback";

var clientSecrets = new ClientSecrets
{
    ClientId = clientID,
    ClientSecret = clientSecret
};

var credential = new GoogleAuthorizationCodeFlow(new GoogleAuthorizationCodeFlow.Initializer
{
    ClientSecrets = clientSecrets,
    Scopes = new[] { GoogleScope.ImapAndSmtp.Name, GoogleScope.EmailScope.Name}
});
' VB.NET 

Dim clientID As String = "XXX.apps.googleusercontent.com"
Dim clientSecret As String = "IxBs0g5sdaSDUz4Ea7Ix-Ua"
Dim redirectUri As String = "http://www.yourdomain.com/oauth2callback"

Dim clientSecrets = New ClientSecrets() With { _
	Key .ClientId = clientID, _
	Key .ClientSecret = clientSecret _
}

Dim credential = New GoogleAuthorizationCodeFlow(New GoogleAuthorizationCodeFlow.Initializer() With { _
	Key .ClientSecrets = clientSecrets, _
	Key .Scopes = New () {GoogleScope.ImapAndSmtp.Name, GoogleScope.EmailScope.Name} _
})

Turn on Google+ API

Remember to turn on Google+ API:
Turn on Google+ API

It is required to obtain email address of the user.

Obtain an OAuth 2.0 access token

Now we’ll create authorization url:


AuthorizationCodeRequestUrl url = credential.CreateAuthorizationCodeRequest(redirectUri);

' VB.NET 

Dim url As AuthorizationCodeRequestUrl = credential.CreateAuthorizationCodeRequest(redirectUri)

Now we need to redirect the client:

// c#

return new RedirectResult(url.Build().ToString());

' VB.NET 

Return New RedirectResult(url.Build().ToString())

At this point user is redirected to Google to authorize the access:

After this step user is redirected back to your website (http://www.yourdomain.com/oauth2callback), with code request parameter:
http://www.yourdomain.com/oauth2callback?code=4/5Y7M4cARD9hrt0nuKnQa0YgtYMasdbwprRtIIjk4Fus#

// c#

public class OAauth2CallbackController : Controller
{
    public ActionResult Index(string code)
    {
        ...
    }
}
' VB.NET 

Public Class OAauth2CallbackController
    Inherits Controller
    Public Function Index(code As String) As ActionResult
        ...
    End Function
End Class

Following is this callback code. Its purpose is to get a refresh-token and an access-token:

// c#

string authCode = code;

TokenResponse token = await credential.ExchangeCodeForTokenAsync("", authCode, redirectUri, CancellationToken.None);

string accessToken = token.AccessToken;
' VB.NET 

Dim authCode As String = code

Dim token As TokenResponse = Await credential.ExchangeCodeForTokenAsync("", authCode, redirectUri, CancellationToken.None)

Dim accessToken As String = token.AccessToken

An access token is usually valid for a maximum of one hour, and allows you to access the user’s data. You also received a refresh token. A refresh token can be used to request a new access token once the previous expired.

Access IMAP/SMTP server

Finally we’ll ask Google for user’s email and use LoginOAUTH2 method to access Gmail’s IMAP server:

// c#

GoogleApi api = new GoogleApi(accessToken);
string user = api.GetEmailPlus();

using (Imap imap = new Imap())
{
    imap.ConnectSSL("imap.gmail.com");
    imap.LoginOAUTH2(user, accessToken);

    imap.SelectInbox();
    List<long> uids = imap.Search(Flag.Unseen);

    foreach (long uid in uids)
    {
        var eml = imap.GetMessageByUID(uid);
        IMail email = new MailBuilder().CreateFromEml(eml);
        Console.WriteLine(email.Subject);
    }
    imap.Close();
}
' VB.NET 

Dim api As New GoogleApi(accessToken)
Dim user As String = api.GetEmailPlus()

Using imap As New Imap()
	imap.ConnectSSL("imap.gmail.com")
	imap.LoginOAUTH2(user, accessToken)

	imap.SelectInbox()
	Dim uids As List(Of Long) = imap.Search(Flag.Unseen)

	For Each uid As Long In uids
		Dim eml = imap.GetMessageByUID(uid)
		Dim email As IMail = New MailBuilder().CreateFromEml(eml)
		Console.WriteLine(email.Subject)
	Next
	imap.Close()
End Using

Refreshing access token

An access token is usually short lived and valid for a maximum of one hour. The main reason behind this is security and prevention of replay attacks. This means that for long-lived applications you need to refresh the access token.

Your refresh token will be sent only once – don’t loose it!

We recommend storing entire TokenResponse object received from GoogleAuthorizationCodeFlow.ExchangeCodeForTokenAsync method call. This object contains both: refresh token and access token, along with its expiration time.

The process of refreshing access token is simple:

// c#

TokenResponse refreshed = await credential.RefreshTokenAsync("", token.RefreshToken, CancellationToken.None);

' VB.NET 

Dim refreshed As TokenResponse = Await credential.RefreshTokenAsync("", token.RefreshToken, CancellationToken.None)

Logging in Mail.dll

Monday, August 1st, 2016

To enable logging for Mail.dll clients (Imap, Pop3, Smtp) you only need to add the following line before you connect:

// C# version:

Limilabs.Mail.Log.Enabled = true;

' VB.NET version:

Limilabs.Mail.Log.Enabled = True

You can observe the log output by:

  • looking at the Visual Studio’s output window (View/Output/’Show output from’: Debug)
  • subscribing to Log.WriteLine event
  • defining custom listeners using your application’s config file (App.config or Web.config)
  • using log4net

This is how the log looks like in the Visual Studio’s output window:

You can also enable logging using your application’s config file (App.config, Web.config):

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
    <system.diagnostics>

      <switches>
        <add name="Mail.dll" value="Verbose" />
      </switches>

    </system.diagnostics>
</configuration>

log4net

If you are using the latest version of log4net.dll, Mail.dll is going to use log4net instead of standard .NET System.Net.TraceSource class. Please refer to log4net manual on how to capture log entries.

Mail.dll uses logger called “Mail.dll” (_logger = LogManager.GetLogger(“Mail.dll”)) and level Info (_logger.Info(message)) to log information.

Please remember that even when using log4net, you need to enable logging by setting “Limilabs.Mail.Log.Enabled = True” or by setting Mail.dll trace switch in the config file (App.config, Web.config) to Verbose as shown above.

Log to file

You’ll need to define a TextWriterTraceListener that writes to a file and connect it with Mail.dll trace source. The easiest solution is to modify your application’s config file (App.config, Web.config) accordingly:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
    <system.diagnostics>

        <trace autoflush="true"/>
   
        <switches>
            <add name="Mail.dll" value="Verbose"/>
        </switches>
   
        <sources>
            <source name="Mail.dll">
                <listeners>
                    <add name="MailLogFile"/>
                </listeners>
            </source>
        </sources>
   
        <sharedListeners>
            <add 
                name="MailLogFile" 
                type="System.Diagnostics.TextWriterTraceListener" 
                initializeData="c:\folder-with-write-access\mail.log"/>
        </sharedListeners>

    </system.diagnostics>
</configuration>

Log.WriteLine

Log class exposes WriteLine event. You can use that event to subscribe your own logging library.

// C#

Limilabs.Mail.Log.WriteLine += Console.WriteLine;
' VB.NET

Limilabs.Mail.Log.WriteLine += Console.WriteLine

Delete email permanently in Gmail

Friday, September 4th, 2015

If you delete a message from your Inbox or one of your custom folders, it will still appear in [Gmail]/All Mail.

Here’s why: in most folders, deleting a message simply removes that folder’s label from the message, including the label identifying the message as being in your Inbox.

[Gmail]/All Mail shows all of your messages, whether or not they have labels attached to them.

If you want to permanently delete a message from all folders:

  1. Move it to the [Gmail]/Trash folder (or [Gmail]/Bin or national version).
  2. Delete it from the [Gmail]/Trash folder (or [Gmail]/Bin or national version).

All emails in [Gmail]/Spam and [Gmail]/Trash are deleted after 30 days.
If you delete a message from [Gmail]/Spam or [Gmail]/Trash, it will be deleted permanently.

Here’s how this looks like using Mail.dll .NET IMAP component:

// C# version:

using(Imap imap = new Imap())
{
	imap.ConnectSSL("imap.gmail.com");
	imap.UseBestLogin("user@gmail.com", "password");

	// Recognize Trash folder
	List<FolderInfo> folders = imap.GetFolders();
 	CommonFolders common = new CommonFolders(folders);
 	FolderInfo trash = common.Trash;

	// Find all emails we want to delete
	imap.SelectInbox();
	List<long> uids = imap.Search(Expression.Subject("email to delete"));

	// Move email to Trash
	List<long> uidsInTrash = new List<long>();
	foreach (long uid in uids)
	{
		long uidInTrash = (long)imap.MoveByUID(uid, trash);
		uidsInTrash.Add(uidInTrash);
	}

	// Delete moved emails from Trash
	imap.Select(trash);
	foreach (long uid in uidsInTrash)
	{
		imap.DeleteMessageByUID(uid);
	}

	imap.Close();
}
' VB.NET version:

Using imap As New Imap()
	imap.ConnectSSL("imap.gmail.com")
	imap.UseBestLogin("user@gmail.com", "password")

	' Recognize Trash folder
	Dim folders As List(Or FolderInfo) = imap.GetFolders()
	Dim common As CommonFolders = new CommonFolders(folders)
	Dim trash As FolderInfo = common.Trash

	' Find all emails we want to delete
	imap.SelectInbox()
	Dim uids As List(Of Long) = imap.Search(_
		Expression.Subject("email to delete"))

	' Move email to Trash
	Dim uidsInTrash As New List(Of Long)
	For Each uid As Long In uids
		Dim uidInTrash As Long = imap.MoveByUID(uid, trash)
		uidsInTrash.Add(uidInTrash)
	Next

	' Delete moved emails from Trash
	imap.[Select](trash)
	For Each uid As Long In uidsInTrash
		imap.DeleteMessageByUID(uid)
	Next

	imap.Close()
End Using

You can also use bulk methods to handle large amount of emails faster:

// C# version:

using(Imap imap = new Imap())
{
	imap.ConnectSSL("imap.gmail.com");
	imap.UseBestLogin("user@gmail.com", "password");

	// Recognize Trash folder
	List<FolderInfo> folders = imap.GetFolders();
 	CommonFolders common = new CommonFolders(folders);
 	FolderInfo trash = common.Trash;

	// Find all emails we want to delete
	imap.SelectInbox();
	List<long> uids = imap.Search(Expression.Subject("email to delete"));

	// Move emails to Trash
	List<long> uidsInTrash = imap.MoveByUID(uids, trash);

	// Delete moved emails from Trash
	imap.Select(trash);
	imap.DeleteMessageByUID(uidsInTrash);

	imap.Close();
}
' VB.NET version:

Using imap As New Imap()
	imap.ConnectSSL("imap.gmail.com")
	imap.UseBestLogin("user@gmail.com", "password")

	' Recognize Trash folder
	Dim folders As List(Or FolderInfo) = imap.GetFolders()
	Dim common As CommonFolders = new CommonFolders(folders)
	Dim trash As FolderInfo = common.Trash

	' Find all emails we want to delete
	imap.SelectInbox()
	Dim uids As List(Of Long) = imap.Search(Expression.Subject("email to delete"))

	' Move email to Trash
	Dim uidsInTrash As List(Of Long) = imap.MoveByUID(uids, trash)

	' Delete moved emails from Trash
	imap.[Select](trash)
	imap.DeleteMessageByUID(uidsInTrash)

	imap.Close()
End Using

Please also note that there are 2 additional sections in the “Gmail settings”/”Forwarding and POP/IMAP” tab:

“When I mark a message in IMAP as deleted:”

  • Auto-Expunge on – Immediately update the server. (default)
  • Expunge off – Wait for the client to update the server.

“When a message is marked as deleted and expunged from the last visible IMAP folder:”

  • Archive the message (default)
  • Move the message to the Trash
  • Immediately delete the message forever

Those settings change the default behavior of the account and modify DeleteMessage* methods behavior.

Using Limilabs’ Ftp.dll with zOS Mainframes

Wednesday, December 17th, 2014

I purchased the Limilabs FTP product for FTP because I needed to send data to and from an IBM mainframe from my VB.NET program running in Windows. In particular I needed to be able to submit jobs, and receive the job output. These notes show how it’s done.

Introduction

FTP to/from IBM computers is pretty much like any other FTP except for two things.
1. IBM Mainframe and Midrange computers mostly use EBCDIC encoding rather than ASCII. With the FTP defaults your data can be garbled and useless when it arrives at the other end.
2. The SITE command is used to submit jobs to the mainframe, and get the results back.

Getting Started

I created a class called “JazzFTP” to wrap the Limilabs’ code. This was going to contain the functions that I wanted for my project, and so I started by defining the common elements that all methods would use. In my situation every FTP would be authenticated, and would be exchanging text data (not binary) with the remote computer.

Here is the initial class definition:

Imports Limilabs.FTP.Client

Public Class JazzFTP
    '   This class wraps the FTP library from Limilabs (/ftp)
    '   All methods
    '   1   Connect and logon using information from MySettings:  Sub LoginFTP
    '   2   Perform their action based on their parameters
    '   3   Close the connection
    Dim ftp As New Ftp()
    Dim response As FtpResponse
    Private Sub LoginFTP()
        ftp.Connect(My.Settings.SubmitIP)
        ftp.Login(My.Settings.Userid, My.Settings.Password)
    End Sub
    '   My functions will be written here
End Class

Basic FTP

Here is my first method, a basic function to upload a text file: –

    Function Upload(DestinationFile As String, Uploadfile As String) As String 
        LoginFTP()
        ftp.TransfersDataType = FtpDataType.Ascii
        response = ftp.Upload(DestinationFile, Uploadfile)
        ftp.Close()
        Return response.message
    End Function

FTP’s default is Binary, which is correct if you are transmitting a .JPG or other binary object, and it probably doesn’t matter if you are transmitting text to/from another Windows computer or a Unix computer. However if you are transmitting to/from an IBM mainframe or midrange computer it probably needs EBCDIC rather than ASCII characters. You must tell it that the file is Ascii text, not binary, otherwise it won’t be converted and it will be gibberish when you examine it on the mainframe.

Although this code above works, it is very fragile: the FTP server has to be up and running, you have to get the connection details exactly right, the source and destination files must exist, and so on. Since I couldn’t guarantee all of these details, I enclosed the code in Try/Catch to deal with any errors. For the time being I’ve simply used MsgBox to display the error message.

    Function Upload(DestinationFile As String, Uploadfile As String) As String
        Try
            LoginFTP()
            ftp.TransfersDataType = FtpDataType.Ascii
            response = ftp.Upload(DestinationFile, Uploadfile)
            ftp.Close()
            Return response.EndLine
        Catch ex As Exception
            MsgBox(ex.Message)
            Return ex.Message
        End Try
    End Function

Download, which is not illustrated, is similar except that you’d use ftp.Download. Again, you specify:

            ftp.TransfersDataType = FtpDataType.Ascii

Submitting Jobs and Receiving Job Output

Submitting a job is essentially an upload with a twist. Instead of uploading the file containing the job to a named file on the mainframe, you upload it to the JES (Job Entry System) input queue. Here is the basic code:

            response = ftp.Site("FILETYPE=JES")
            ftp.TransfersDataType = FtpDataType.Ascii
            response = ftp.Upload("JES", JCLFile)

The first line uses “ftp.Site”. Site means that this is a site-specific command, something that the FTP system at the other end will presumably know about. For an IBM mainframe “FILETYPE=JES” means that the data is going to and from JES.

The third line uploads the file in which we have prepared our job: in this case JCLFile is a file containing something like this: –

//IBMUSERH JOB  ,CLASS=A,MSGCLASS=H,NOTIFY=&SYSUID,COND=(8,LT) 
//*** COPY SOURCE INTO SOURCE LIBRARY
//COPY EXEC PGM=IEBGENER
//SYSPRINT DD SYSOUT=*
//SYSIN DD DUMMY
//SYSUT2 DD DSN=IBMUSER.MANAJAZZ.SRCLIB(CRDTA1),DISP=SHR
//SYSUT1 DD *

Like any upload the FTP client syntax requires a destination file name, but because of the preceding FILETYPE=JES this will be ignored. I have written “JES” purely for documentation.

This will submit the job and it will run, appearing in the output like this:

tasks

Of course we can view the job output on the mainframe, but we may want to return it to Windows. We do this by downloading the file by naming the JobID – JOB00594 in this case – and again using the Site command. The essential code is: –

        response = ftp.Site("FILETYPE=JES")
        ftp.TransfersDataType = FtpDataType.Ascii
        ftp.Download(Jobname, LocalPath)

But how do we get the Jobname? JES returns a message with this information when the job is submitted. We need to add code to the Job Submission logic to extract this from the message. In function JobSub

       response = ftp.Upload("JES", JCLFile)

upload the job and (if all goes well) returns a message like
“It is known to JES as JOB00594″
This code extracts JOB00594” and puts it into variable JobName

       Dim TestString As String = "It is known to JES as"
       If Mid(response.Message, 1, Len(TestString)) = TestString Then  'Should be true
           Jobname = Trim(Mid(response.Message, Len(TestString) + 1))
       End If

Now, since it is logical that if we submit a job we’ll want to get it back, I coded this in the JobSub function: –

    Function JobSub(JCLFile As String, ByRef Jobname As String) As FtpResponse
        '   JCLFile is path to a .JCL file (format .txt) containing the job to be submitted
        '   If successful submission, the job name is returned in JobName
        Dim Tstring As String = ""
        Try
            Jobname = "Unknown"
            LoginFTP()
            response = ftp.Site("FILETYPE=JES")
            ftp.TransfersDataType = FtpDataType.Ascii
            response = ftp.Upload("JES", JCLFile)
            Dim TestString As String = "It is known to JES as"
            If Mid(response.Message, 1, Len(TestString)) = TestString Then  'Should be true
                Jobname = Trim(Mid(response.Message, Len(TestString) + 1))
            End If
            JobGet(Jobname, False)
            ftp.Close()
        Catch ex As Exception
            MsgBox(ex.Message, MsgBoxStyle.OkOnly, "Jazz FTP")
            Return response
        End Try
        Return response
    End Function

and I coded JobGet to accept these parameters: –

    Function JobGet(Jobname As String, Optional Login As Boolean = True) As FtpResponse
        '   Get job output, save as Jobname.txt in Jazz Program Library.  
        If Login Then
            LoginFTP()
        End If
        response = ftp.Site("FILETYPE=JES")
        ftp.TransfersDataType = FtpDataType.Ascii
        Dim LocalPath As String = My.Settings.UserCommonPath & "\" & My.Settings.Programs & "\" & Jobname & ".txt"
        Jazzworkbench.ShowBtnResults(Jobname, Jazzworkbench.ResultsStatus.Pending)
        ftp.Download(Jobname, LocalPath)
        ftp.DeleteFile(Jobname)
        Jazzworkbench.ShowBtnResults(Jobname, Jazzworkbench.ResultsStatus.JobReturned)
        ftp.Close()
        Return response
    End Function

Once the job output has been downloaded I didn’t want to leave it cluttering up my Held Job Output Queue, so after the Download

        ftp.DeleteFile(Jobname)

gets rid of it.

This all works for my test jobs (which are very quick) and provided that mainframe FTP server is available.

If you want to know any more about my project to revolutionize mainframe programming, then have a look at www.jazzsoftware.co.nz

Best wishes with your programming,
Robert Barnes.