Kafka-connect sink task ignores file offset storage property : <p>I'm experiencing quite weird behavior working with Confluent JDBC connector. I'm pretty sure that it's not related to Confluent stack, but to Kafka-connect framework itself.</p>

<p>So, I define <code>offset.storage.file.filename</code> property as default <code>/tmp/connect.offsets</code> and run my sink connector. Obviously, I expect connector to persist offsets in the given file (it doesn't exist on file system, but it should be automatically created, right?). Documentation says:</p>

<blockquote>
  <p><code>offset.storage.file.filename</code>
  The file to store connector offsets in. By storing offsets on disk, a standalone process can be stopped and started on a single node and resume where it previously left off.</p>
</blockquote>

<p>But Kafka behaves in completely different manner.</p>

<ol>
<li>It checks if the given file exists.</li>
<li>It it's not, Kafka just ignores it and persists offsets in Kafka topic.</li>
<li>If I create given file manually, reading fails anyway (EOFException) and offsets are being persisted in topic again.</li>
</ol>

<p>Is it a bug or, more likely, I don't understand how to work with this configurations? I understand difference between two approaches to persist offsets and file storage is more convenient for my needs.</p>
