将文件（例如屏幕截图）附加到log4net smtp附加程序

Question

I would like to attach a file with the log sent by the log4net smtp appender. This would allow us to include screenshots or input file data with the email log.

Is there anyway to do this automatically out of the box. I can't seem to find any information on this, and am guessing we would need to either do this separate to the log4net logging or write the information inside the log (but that would need us to deserialise it after receiving the email).

Answer 1

You can do it with your own smtp appender, here is the code I use to send mail to multiple users, with a custom subject and attachment:

• In the config file

For the custom subject:

<layoutSubject type="log4net.Layout.PatternLayout,log4net">
    <conversionPattern value="Custom subject %level in application" />
</layoutSubject>

For the multiple recipients:

email1@domain.com;email2@domain.com;...

• In your log class

The code you have to call everytimes you want to add an attachment.
Careful, you have to adapt this one to your program!

private static void AddAttachment(string Attachment)
{
    if (!string.IsNullOrEmpty(Attachment))
    {
        if (File.Exists(Attachment))
        {
            foreach (IAppender Appender in Log.log.Logger.Repository.GetAppenders())
            {
                if (Appender.GetType().ToString().IndexOf(".SmtpCustomAppender") != -1)
                {
                    ((SmtpCustomAppender)(Appender)).Attachment = Attachment;
                }
            }
        }
        else
        {
            VPLog.Log4Net.LogWarning(string.Format("Le fichier {0} est introuvable sur le disque, il sera ignoré.", Attachment));
        }
    }
}

And the big one, the custom appender:

public class SmtpCustomAppender : log4net.Appender.SmtpAppender
{
    public SmtpCustomAppender()
        : base()
    {
    }
    public ILayout LayoutSubject { get; set; }
    public bool IsBodyHtml { get; set; }
    public string Attachment { get; set; }

    protected override void SendEmail(string messageBody)
    {
        // .NET 2.0 has a new API for SMTP email System.Net.Mail
        // This API supports credentials and multiple hosts correctly.
        // The old API is deprecated.

        // Create and configure the smtp client
        SmtpClient smtpClient = new SmtpClient();
        if (!String.IsNullOrEmpty(this.SmtpHost))
        {
            smtpClient.Host = this.SmtpHost;
        }
        smtpClient.Port = this.Port;
        smtpClient.DeliveryMethod = SmtpDeliveryMethod.Network;
        smtpClient.EnableSsl = this.EnableSsl;

        if (Authentication == SmtpAuthentication.Basic)
        {
            // Perform basic authentication
            smtpClient.Credentials = new System.Net.NetworkCredential(Username, Password);
        }
        else if (Authentication == SmtpAuthentication.Ntlm)
        {
            // Perform integrated authentication (NTLM)
            smtpClient.Credentials = System.Net.CredentialCache.DefaultNetworkCredentials;
        }

        using (System.Net.Mail.MailMessage mailMessage = new System.Net.Mail.MailMessage())
        {
            mailMessage.IsBodyHtml = IsBodyHtml;
            mailMessage.Body = messageBody;
            //mailMessage.BodyEncoding = BodyEncoding;
            mailMessage.From = new MailAddress(From);
            foreach(string emailTo in To.Split(';'))
                mailMessage.To.Add(emailTo);
            if (!String.IsNullOrEmpty(Cc))
            {
                foreach (string emailCc in Cc.Split(';'))
                    mailMessage.CC.Add(emailCc);
            }
            if (!String.IsNullOrEmpty(Bcc))
            {
                foreach (string emailBcc in Bcc.Split(';'))
                    mailMessage.Bcc.Add(emailBcc);
            }
            if (!String.IsNullOrEmpty(this.ReplyTo))
            {
                // .NET 4.0 warning CS0618: 'System.Net.Mail.MailMessage.ReplyTo' is obsolete:
                // 'ReplyTo is obsoleted for this type.  Please use ReplyToList instead which can accept multiple addresses. http://go.microsoft.com/fwlink/?linkid=14202'
//#if !NET_4_0
                //mailMessage.ReplyTo = new MailAddress(this.ReplyTo);
//#else
                mailMessage.ReplyToList.Add(new MailAddress(this.ReplyTo));
//#endif
            }
            mailMessage.Subject = this.Subject;
            //mailMessage.SubjectEncoding = m_subjectEncoding;
            mailMessage.Priority = this.Priority;

            #region on ajoute la ou les pièce(s) jointe(s)
            if (!string.IsNullOrEmpty(Attachment))
            {
                var attachments = Attachment.Split(';');
                foreach (var attach in attachments)
                {
                    if (!string.IsNullOrEmpty(attach.Trim()))
                    {
                        var path = attach.Trim();
                        try
                        {
                            var context = HttpContext.Current;
                            if (context == null) //context non web
                            {
                                //on teste s'il s'agit d'un chemin absolu ou non
                                if (!Path.IsPathRooted(path))
                                {
                                    path = Directory.GetCurrentDirectory() + "\\" + path;
                                }

                                if (File.Exists(path))
                                {
                                    //si le fichier spécifié existe bien, on l'ajoute en pièce jointe au mail
                                    AttachFile(mailMessage, path);
                                }
                                else
                                {
                                    // Sinon, on écrit dans le corps du mail que le fichier n'a pas été trouvé
                                    mailMessage.Body += IsBodyHtml ? "<br/>" : Environment.NewLine;
                                    mailMessage.Body += IsBodyHtml ? "<br/>" : Environment.NewLine;
                                    mailMessage.Body += "Fichier non trouvé: " + attach;
                                }
                            }
                            else //context web
                            {
                                //on teste s'il s'agit d'un chemin absolu ou non
                                if (!Path.IsPathRooted(path))
                                {
                                    path = context.Server.MapPath(path);
                                }

                                if (File.Exists(path))
                                {
                                    //si le fichier spécifié existe bien, on l'ajoute en pièce jointe au mail
                                    AttachFile(mailMessage, path);
                                }
                                else
                                {
                                    // Sinon, on écrit dans le corps du mail que le fichier n'a pas été trouvé
                                    mailMessage.Body += IsBodyHtml ? "<br/>" : Environment.NewLine;
                                    mailMessage.Body += IsBodyHtml ? "<br/>" : Environment.NewLine;
                                    mailMessage.Body += "Fichier non trouvé: " + attach;
                                }
                            }
                        }
                        catch (Exception ex)
                        {
                            // En cas d'erreur, on précise dans le corps du mail que le fichier n'a pu être joint
                            mailMessage.Body += IsBodyHtml ? "<br/>" : Environment.NewLine;
                            mailMessage.Body += IsBodyHtml ? "<br/>" : Environment.NewLine;
                            mailMessage.Body += string.Format("<b>Erreur lors de l'ajout de la piece jointe: {0}</b>", attach);

                            // On logge l'erreur avec le logger interne de log4net
                            VPLog.Log4Net.Log.log.Error(string.Format("Erreur lors de la pièe jointe: {0} (path: {1})", attach, path), ex);
                        }
                        finally
                        {
                            this.Attachment = "";
                        }
                    }
                }
            }
            #endregion

            // TODO: Consider using SendAsync to send the message without blocking. This would be a change in
            // behaviour compared to .NET 1.x. We would need a SendCompletedCallback to log errors.
            smtpClient.Send(mailMessage);
        }
    }


    /// <summary>
    /// On permet la customisation de l'objet du mail
    /// </summary>
    /// <param name="loggingEvent"></param>
    protected override void Append(log4net.Core.LoggingEvent loggingEvent)
    {
        if (this.BufferSize <= 1 && this.LayoutSubject != null)
        {
            #region Custo pour le sujet
            var subjectWriter = new StringWriter(System.Globalization.CultureInfo.InvariantCulture);
            LayoutSubject.Format(subjectWriter, loggingEvent);
            this.Subject = subjectWriter.ToString();
        #endregion
    }
    base.Append(loggingEvent);
}

/// <summary>
/// Attache une pièce jointe au mail
/// </summary>
/// <param name="mailMessage">mailMessage</param>
/// <param name="path">Chemin du fichier</param>
private void AttachFile(System.Net.Mail.MailMessage mailMessage, string path)
{
    var stream = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
    mailMessage.Attachments.Add(new Attachment(stream, Path.GetFileName(Attachment)));
    }
}

Answer 2

This is not supported. It would also be quite hard to support because only a few logging targets can support attaching files.

But you could - as a kind of work around - generate HTML log messages and use data URIs to embed binary data and especially images.

Answer 3

创建具有自己的smpt行为的自己的附加程序， 文章如何执行附加程序

Answer 4

SeleniumLog is an app built just for that - attaching screenshots and any arbitrary files/binaries to the log. It's quite heavy duty and can handle hundreds and thousands of screenshots effortlessly. You could create an appender for it, or just wait as I heard they're working on a log4net plugin for it, among other things.