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<h2>
<a href="index.html"><code>~</code></a>
</h2>
<h1>
<a
id="user-content-incident-come-and-go"
class="anchor"
aria-hidden="true"
tabindex="-1"
href="#incident-come-and-go"
><span aria-hidden="true" class="octicon octicon-link"></span></a
>Incident come and go
</h1>
<p>This is collect of all incidents I created in the past :(</p>
<h2>
<a
id="user-content-service-starts-with-empty-port"
class="anchor"
aria-hidden="true"
tabindex="-1"
href="#service-starts-with-empty-port"
><span aria-hidden="true" class="octicon octicon-link"></span></a
>Service starts with empty port
</h2>
<p>Because all configs is read from file.</p>
<p>
But the port config is empty -> So when service inits, it use that
empty port somehow.
</p>
<p>
<strong>Solution</strong>: For some configs, make sure to failed first if
it's empty.
</p>
<h2>
<a
id="user-content-race-condition-of-series-of-apis"
class="anchor"
aria-hidden="true"
tabindex="-1"
href="#race-condition-of-series-of-apis"
><span aria-hidden="true" class="octicon octicon-link"></span></a
>Race condition of series of APIs
</h2>
<p>For example I have 2 APIs:</p>
<ul>
<li>API upload: allow user to upload image</li>
<li>API submit: submit data to server</li>
</ul>
<p>
API upload is slow, it takes 10s to finish. API submit is fast, only takes
2s.
</p>
<p>
The problem is submit use data from upload too. When user calls API
upload, image is stored in cache. When user calls API submit, it use
whatever image is stored in cache.
</p>
<p>It's when the fun begins.</p>
<p>
Imagine user Trong already upload image. So he is ready to submit. But for
the same time, he re-call API upload to upload another image too.
</p>
<p>
So if API upload is finished first, which is kinda impossible (U know
upload file is not fast right?), everything right. But for most cases, API
submit is finished first. It means Trong's data is submitted with the old
image. Then API upload is finished, it will replace the old image with the
new one.So the old one, aka image in submitted data, is gone.
</p>
<p>Chaos right there!</p>
<p>
<strong>Solution</strong>: Use a lock, if user enter API upload, lock it
to prevent user call other APIs. Rememeber to unlock after finished
</p>
<div>
Feel free to ask me via
<a href="mailto:hauvipapro+posts@gmail.com">email</a> or
<a rel="me" href="https://hachyderm.io/@haunguyen">Mastodon</a>.
<br />Source code is available on
<a href="https://github.com/haunt98/posts-go">GitHub</a>
<a href="https://codeberg.org/yoshie/posts-go">Codeberg</a>
<a href="https://git.sr.ht/~youngyoshie/posts-go">sourcehut</a>
<a href="https://gitea.treehouse.systems/yoshie/posts-go">Treehouse</a>
<a href="https://gitlab.com/youngyoshie/posts-go">GitLab</a>
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