C++

Fetch a Chunk of Messages, Tracking Failures

Demonstrates the Chilkat Imap.FetchChunk2 method, which downloads a run of messages by sequence number and reports which succeeded and which failed. The arguments are the starting sequence number, the count, a MessageSet that receives the failed IDs, a MessageSet that receives the successfully-fetched IDs, and the EmailBundle. This example fetches the first chunk of messages and reports the success and failure counts.

Background: When bulk-downloading a large mailbox, individual messages can occasionally fail to fetch (a corrupt message on the server, a transient error) without failing the whole operation. FetchChunk2 is designed for that reality: it returns a partial EmailBundle plus two MessageSet objects so your code can log or retry exactly the messages that did not come through, rather than aborting the entire sync.

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C++

#include <CkImap.h>
#include <CkMessageSet.h>
#include <CkEmailBundle.h>

void ChilkatSample(void)
    {
    bool success = false;

    //  Demonstrates the Imap.FetchChunk2 method, which downloads a run of messages by sequence
    //  number and reports which succeeded and which failed.  The 1st argument is the starting
    //  sequence number, the 2nd is the count, the 3rd receives the failed IDs, the 4th receives
    //  the successfully-fetched IDs, and the 5th is the EmailBundle.

    CkImap imap;

    imap.put_Ssl(true);
    imap.put_Port(993);

    success = imap.Connect("imap.example.com");
    if (success == false) {
        std::cout << imap.lastErrorText() << "\r\n";
        return;
    }

    success = imap.Login("user@example.com","myPassword");
    if (success == false) {
        std::cout << imap.lastErrorText() << "\r\n";
        return;
    }

    int numMessages = imap.SelectMailbox("Inbox");
    if (numMessages < 0) {
        std::cout << imap.lastErrorText() << "\r\n";
        return;
    }

    //  Fetch messages 1..25 (or fewer if the mailbox is smaller).
    int count = 25;
    if (count > numMessages) {
        count = numMessages;
    }

    CkMessageSet failedSet;
    CkMessageSet fetchedSet;
    CkEmailBundle bundle;
    success = imap.FetchChunk2(1,count,failedSet,fetchedSet,bundle);
    if (success == false) {
        std::cout << imap.lastErrorText() << "\r\n";
        return;
    }

    std::cout << "Fetched: " << fetchedSet.get_Count() << "\r\n";
    std::cout << "Failed:  " << failedSet.get_Count() << "\r\n";

    success = imap.Disconnect();
    if (success == false) {
        std::cout << imap.lastErrorText() << "\r\n";
        return;
    }
    }