PHP ActiveX Requires Chilkat v11.5.0+

Box: Poll User Events and Save a Checkpoint

See more Box Examples

Poll the authenticated user event stream in bounded batches. The local JSON checkpoint keeps processed event IDs and the next stream position. This single-process demonstration logs events; a production worker should commit its business action, deduplication record, and cursor transactionally and prune old IDs.

See the Box API guide for setup and the complete workflow.

PHP ActiveX

<?php

$success = 0;

//  Requires Chilkat 11.5.0 or later and a previously unlocked Chilkat bundle.
//  See Global Unlock Sample.
//  Guide: Box API Guide.

$success = 0;

//  Supply an unexpired token obtained with one of the Box authentication examples.
//  A token represents a particular user or service account. IDs must be accessible to it.
$curl = new COM("Chilkat.HttpCurl");
$curl->SetVar('access_token','BOX_ACCESS_TOKEN');

$state = new COM("Chilkat.JsonObject");
$files = new COM("Chilkat.FileAccess");
$statePath = 'qa_data/box_events_state.json';
if ($files->FileExists($statePath) == 1) {
    $success = $state->LoadFile($statePath);
    if ($success != 1) {
        print $state->LastErrorText . "\n";
        exit;
    }

    if ($state->HasMember('position') != 1) {
        print 'Invalid checkpoint: position missing.' . "\n";
        exit;
    }

}
else {
    //  "now" starts a new subscription. It deliberately skips historical events.
    $state->UpdateString('position','now');
}

$curl->SetVar('position',$state->stringOf('position'));
$page = new COM("Chilkat.JsonObject");
$seenPath = new COM("Chilkat.StringBuilder");

$batch = 0;

$more = 1;
while (($more == 1) and ($batch < 20)) {
    $curl->ClearTargetOutput('*');
    $authorizedCommand1 = new COM("Chilkat.StringBuilder");
    $authorizedCommand1->SetString('curl -X GET \'https://api.box.com/2.0/events?stream_type=all&stream_position={{position}}&limit=100\' -H \'Authorization: Bearer {{access_token}}\'');
    $headerReplacement1 = $authorizedCommand1->Replace('{{access_token}}',$curl->getVar('access_token'));
    $success = $curl->DoYourThing($authorizedCommand1->getAsString());
    if (($success != 1) or ($curl->StatusCode != 200)) {
        print 'Box request failed. HTTP status: ' . $curl->StatusCode . "\n";
        print 'Failure reason: ' . $curl->FailReason . "\n";
        print $curl->ResponseBodyStr . "\n";
        exit;
    }

    $success = $curl->GetResponseJson($page);
    if ($success != 1) {
        print $curl->LastErrorText . "\n";
        exit;
    }

    $count = $page->SizeOfArray('entries');
    $i = 0;
    while ($i < $count) {
        $page->I = $i;
        $eventId = $page->stringOf('entries[i].event_id');
        if ($eventId == '') {
            print 'Event without an event_id; checkpoint not advanced.' . "\n";
            exit;
        }

        $seenPath->Clear();
        $seenPath->Append('seen.');
        $seenPath->Append($eventId);
        if ($state->HasMember($seenPath->getAsString()) == 0) {
            //  Replace this logging with your idempotent business operation.
            //  Record success only after that operation succeeds.
            print $eventId . ' ' . $page->stringOf('entries[i].event_type') . ' ' . $page->stringOf('entries[i].source.id') . "\n";
            $state->UpdateBool($seenPath->getAsString(),1);
        }

        $i = $i + 1;
    }

    $nextPosition = $page->stringOf('next_stream_position');
    if ($nextPosition == '') {
        print 'Missing next_stream_position; checkpoint not advanced.' . "\n";
        exit;
    }

    $more = ($count > 0) and ($nextPosition != $curl->getVar('position'));
    $state->UpdateString('position',$nextPosition);
    $success = $state->WriteFile($statePath);
    if ($success != 1) {
        print $state->LastErrorText . "\n";
        exit;
    }

    $curl->SetVar('position',$nextPosition);
    $batch = $batch + 1;
}

print 'Checkpoint saved. Run again later to continue polling.' . "\n";

?>