(Go) Process Large POP3 Mailbox

Demonstrates how to read email from a mailbox that may contain a large number of emails.

Chilkat Go Downloads Go Package for Windows, MacOS, Linux, Alpine Linux, Solaris

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

    mailman := chilkat.NewMailMan()

    mailman.SetMailHost("pop.example.com")

    mailman.SetPopUsername("myLogin")
    mailman.SetPopPassword("myPassword")

    mailman.SetMailPort(995)
    mailman.SetPopSsl(true)

    // Get the list of UIDLs for all emails in the mailbox.
    sa := mailman.GetUidls()
    if mailman.LastMethodSuccess() == false {
        fmt.Println(mailman.LastErrorText())
        mailman.DisposeMailMan()
        return
    }

    var i int
    numEmails := sa.Count()
    if numEmails == 0 {
        fmt.Println("Mailbox is empty")
        mailman.DisposeMailMan()
        return
    }

    chunkSize := 6

    // Download the emails in chunks of 6 emails each.
    chunkBeginIdx := 0
    chunkEndIdx := chunkSize - 1
    if chunkEndIdx >= numEmails {
        chunkEndIdx = numEmails - 1
    }

    saChunk := chilkat.NewStringArray()
    for (chunkBeginIdx < numEmails) {

        fmt.Println(chunkBeginIdx, " to ", chunkEndIdx)

        // Build a chunk of UIDLs.
        saChunk.Clear()
        for i = chunkBeginIdx; i <= chunkEndIdx; i++ {
            saChunk.Append(*sa.GetString(i))
        }

        // Log the UIDLs in this chunk...
        chunkStr := saChunk.SaveToText()
        fmt.Println(*chunkStr)

        // Download this chunk of email from the POP3 server.
        bundle := mailman.FetchMultiple(saChunk)
        if mailman.LastMethodSuccess() == false {
            fmt.Println(mailman.LastErrorText())
            mailman.DisposeMailMan()
            saChunk.DisposeStringArray()
            return
        }

        fmt.Println("Downloaded ", bundle.MessageCount(), " emails.")
        fmt.Println("----")

        // Process the bundle...
        // (your application's processing code goes here...)

        bundle.DisposeEmailBundle()

        // Get the next chunk...
        chunkBeginIdx = chunkBeginIdx + chunkSize
        chunkEndIdx = chunkEndIdx + chunkSize
        if chunkEndIdx >= numEmails {
            chunkEndIdx = numEmails - 1
        }

    }

    sa.DisposeStringArray()

    mailman.DisposeMailMan()
    saChunk.DisposeStringArray()