PHP 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.

Chilkat2 PHP

<?php

use Chilkat2\FileAccess;
use Chilkat2\HttpCurl;
use Chilkat2\JsonObject;
use Chilkat2\StringBuilder;

$success = false;

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

$success = false;

// 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 HttpCurl();
$curl->SetVar('access_token', 'BOX_ACCESS_TOKEN');

$state = new JsonObject();
$files = new FileAccess();
$statePath = 'qa_data/box_events_state.json';
if ($files->FileExists($statePath)) {
    try {
        $state->LoadFile($statePath);
    } catch (\Chilkat2\Exception $e) {
        echo $e->getMessage(), "\n";
        exit;
    }

    if (!$state->HasMember('position')) {
        echo "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 JsonObject();
$seenPath = new StringBuilder();
$eventId = '';
$nextPosition = '';
$batch = 0;
$i = 0;
$count = 0;
$more = true;
while (($more) && ($batch < 20)) {
    $curl->ClearTargetOutput('*');
    $authorizedCommand1 = new 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'));
    try {
        $curl->DoYourThing($authorizedCommand1->GetAsString());
        $success = true;
    } catch (\Chilkat2\Exception $e) {
        $success = false;
    }
    if ((!$success) || ($curl->StatusCode != 200)) {
        echo 'Box request failed. HTTP status: ', $curl->StatusCode, "\n";
        echo 'Failure reason: ', $curl->FailReason, "\n";
        echo $curl->ResponseBodyStr, "\n";
        exit;
    }

    try {
        $curl->GetResponseJson($page);
    } catch (\Chilkat2\Exception $e) {
        echo $e->getMessage(), "\n";
        exit;
    }

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

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

        $i = $i + 1;
    }

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

    $more = ($count > 0) && ($nextPosition !== $curl->GetVar('position'));
    $state->UpdateString('position', $nextPosition);
    try {
        $state->WriteFile($statePath);
    } catch (\Chilkat2\Exception $e) {
        echo $e->getMessage(), "\n";
        exit;
    }

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

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