(Swift 3,4,5...) Load .eml and Examine the Structure, Attachments, and Related Items

Demonstrates how to load examine the MIME structure of a .eml, and also examine the attachment and related item filenames, attached messages, and multipart/report and DSN information.

Chilkat Downloads for the Swift Programming Language MAC OS X (Cocoa) Objective-C/Swift Libs iOS Objective-C/Swift Libs

func chilkatTest() {
    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    var emlPath: String? = "C:/AAWorkarea/beatrix/roesner.eml"

    let mime = CkoMime()!

    var success: Bool = mime.loadFile(emlPath)
    if success != true {
        print("\(mime.lastErrorText!)")
        return
    }

    print("---- MIME structure ----")
    print("\(mime.getStructure("text")!)")
    print("------------------------")

    let email = CkoEmail()!
    success = email.loadEml(emlPath)

    // Was this a signed and/or encrypted email?
    // If so, then loading the .eml automatically unwraps
    // (i.e. verifies signatures and decrypts) and the resultant
    // email is what existed prior to signing/encrypting.
    print("Email was Signed: \(email.receivedSigned)")
    print("Email was Encrypted: \(email.receivedEncrypted)")
    if email.receivedSigned == true {
        print("Signature(s) valid = \(email.signaturesValid)")
    }

    if email.receivedEncrypted == true {
        print("Decrypted successfully = \(email.decrypted)")
    }

    var i: Int = 0
    var numAttach: Int = email.numAttachments.intValue
    print("Number of attachments = \(numAttach)")

    while i < numAttach {
        print("---- Attachment \(i)")

        // Examine the filename (if any)
        print("filename: \(email.getAttachmentFilename(i)!)")
        // Examine the content-ID (if any)
        print("Content-ID: \(email.getAttachmentContentID(i)!)")
        // Examine the content-type
        print("Content-Type: \(email.getAttachmentContentType(i)!)")
        // Examine the content-disposition
        print("Content-Disposition\(email.getAttachmentHeader(i, fieldName: "content-disposition")!)")
        // Examine the attachment size:
        print("Size (in bytes) of the attachment: \(email.getAttachmentSize(i).intValue)")

        i = i + 1
    }

    print("--")

    // Now for the related items.

    // Note: A MIME sub-part can potentially be both a related item AND an attachment.
    // The typical case is when the item is contained under the multipart/related enclosure and 
    // the item also has a "Content-Disposition" header indicating "attachment".
    // The location within multipart/related makes it a "related item", yet the Content-Disposition can also make it semantically an attachment.
    // Related items and attachments are not necessarily mutually exclusive.

    var numRelated: Int = email.numRelatedItems.intValue
    print("Number of related items = \(numRelated)")
    i = 0
    while i < numRelated {
        print("---- Related Item \(i)")

        // Examine the filename (if any)
        print("filename: \(email.getRelatedFilename(i)!)")
        // Examine the content-ID (if any)
        print("Content-ID: \(email.getRelatedContentID(i)!)")
        // Examine the content-type
        print("Content-Type: \(email.getRelatedContentType(i)!)")
        // Examine the content-location (if any)
        print("Content-Location\(email.getRelatedContentLocation(i)!)")

        i = i + 1
    }

    // The email could also have attached messages.
    // An attached message is another email that was attached to this email.
    var numAttachedMessages: Int = email.numAttachedMessages.intValue
    print("Number of attached messages = \(numAttachedMessages)")
    i = 0
    while i < numAttachedMessages {
        print("---- Attached message \(i)")

        // Examine the attached email
        var em: CkoEmail? = email.getAttachedMessage(i)
        print("from: \(em!.from!)")
        print("subject: \(em!.subject!)")
        em = nil
        i = i + 1
    }

    // An email could also be a multipart/report email. 
    // This is a DSN (Delivery Status Notification)
    // The NumReports property indicates how many "reports" exist.
    var numReports: Int = email.numReports.intValue
    i = 0
    print("Number of reports = \(numReports)")
    i = 0
    while i < numReports {
        print("---- Report \(i)")
        // Get the raw report data...
        print("\(email.getReport(i)!)")
        i = i + 1
    }

    // If the email is a multipart/report, then the information
    // from the message/delivery-status part of the email can be retrieved:
    if email.isMultipartReport() == true {

        print("--- Delivery Status Information:")
        print("Status: \(email.getDeliveryStatusInfo("Status")!)")
        print("Action: \(email.getDeliveryStatusInfo("Action")!)")
        print("Reporting-MTA: \(email.getDeliveryStatusInfo("Reporting-MTA")!)")

        var sa: CkoStringArray? = email.getDsnFinalRecipients()
        var numFinalRecipients: Int = sa!.count.intValue
        i = 0
        while i < numFinalRecipients {
            print("final recipient: \(sa!.getString(i)!)")
            i = i + 1
        }

        sa = nil
    }


}