Using maapi_roll_config() to read config rollback

Core Engine and APIs
1

Hi,

I’m trying to use maapi_roll_config() to read the actual rollback configuration after a commit has been done. I call maapi_roll_config() after have received a commit Notification. However, I tried many things, but I never seem to get anything. Is this API known to work? I’m using Confd version 8.0.16.

Thx,

Ice.

2

Hi Ice,

The maapi_roll_config() should be working as documented, but it is not exactly clear that you are using it per the documentation. You mention that you are calling it after you receive a commit Notification. When are you setting up the stream relative to your commit? Can you include some basic code that you are trying this with?

Regards,
Scott

3

Hi Scott, thanks for responding. See below a snipped of the code:

I register for a commit notification using CONFD_NOTIF_COMMIT_DIFF. I call the code below immediately when having received a notification for CONFD_RUNNING.

  char              *confd_ip = (char *)"127.0.0.1";
  int                confd_port = CONFD_PORT;
  char               buf[1024];
  int                datastore = CONFD_RUNNING;
  char              *user = (char *)"admin";
  const char        *groups[] = {"admin"};
  char              *context = (char *)"system";



  maapisock = socket(PF_INET, SOCK_STREAM, 0);
  if (maapisock < 0) {
    goto config_read_cleanup;
  }

  addr.sin_addr.s_addr = inet_addr(confd_ip);
  addr.sin_family = AF_INET;
  addr.sin_port = htons(confd_port);
  src_addr.af = AF_INET;
  inet_aton(confd_ip, &src_addr.ip.v4);

  // Connect to maapi
  res = maapi_connect(maapisock, (struct sockaddr *)&addr,
                      sizeof(struct sockaddr_in));
  if (res < 0) {
    goto config_read_cleanup;
  }

  // Start User Session
  res = maapi_start_user_session(maapisock, user, context, groups, 1, &src_addr,
                               CONFD_PROTO_TCP);
  if (res != CONFD_OK) {
    goto config_read_cleanup;
  }

  thandle = maapi_start_trans(maapisock, datastore, CONFD_READ);
  if (thandle < 0) {
    goto config_read_cleanup;
  }

  id = maapi_roll_config(maapisock, thandle, "/");

  streamsock = socket(PF_INET, SOCK_STREAM, 0);
  confd_stream_connect(streamsock, (struct sockaddr *)&addr,
                       sizeof(struct sockaddr_in), id, 0);
  while ((r = read(streamsock, buf, sizeof(buf))) > 0) {
    printf("Rollback: %s\n", buf);
  }

  // This functions checks if the entire config was read.
  res = maapi_roll_config_result(maapisock, id);
  if (res != CONFD_OK) {
    printf("Maapi roll config result failed (error %i)\n", res);
  }
4

Let me also explain what my intention is, just in case there are other solutions. Based on a commit notification, I want to pull the rollback configuration diff for that commit. I am able to retrieve the list using maapi_list_rollbacks(). Is there a maapi command where I can retrieve the rollback diff using the fixed_nr? So essentially “show configuration rollback changes ”, but with the actual nr, not the relative number.

5

Hi Ice,

I agree it may be best to look for another solution. I was able to get output when I did e.g. a maapi_delete() and then did the maapi_roll_config() on that same socket:

    int sock, tid, id, ssock;
    char buf[size];
    create_maapi_sesssion(addr, &sock, &tid, 0);
    OK(maapi_delete(sock, tid, "/server"));
    assert((id = maapi_roll_config(sock, tid, "/")) > 0);
    if ((ssock = socket(PF_INET, SOCK_STREAM, 0)) < 0)
        confd_fatal("Failed to open stream socket\n");
    OK(confd_stream_connect(ssock,(struct sockaddr*)addr,
                            sizeof (struct sockaddr_in), id, 0));
    while (read(ssock, buf, sizeof(buf)) > 0)
         printf("roll received %s\n", buf);
    maapi_roll_config_result(sock, id);
    close(sock);

with some data:

roll received server abcdefghijklmnopqrstuvwxyz0 {
roll received opqrstuvwxyz1 {
roll received value abcdefghijklmnopqrstuvwxyz10b;
...

But I also didn’t see any data by attaching to the CONFD_RUNNING or even the ‘current’ transaction.