A check is in order:

===
if ( get_query_var('action') ) {
$server->handleRequest();

from wp-update-server.

When using the server as part of a plugin, you're not supposed to just run it blindly. You need to verify the necessary parameters and pass them to the handleRequest() method. Take a look at the example code in the readme. It does check if the action is specified before calling the server:
https://github.com/YahnisElsts/wp-update-server#running-the-server-from-another-script

from wp-update-server.

I think it's best to update the index.php with the same.

from wp-update-server.

I disagree. index.php is the entry point for the stand-alone version of the server. Do you really want it to fail silently if some of the parameters are missing? That would make setup and debugging more difficult.

from wp-update-server.

I'm trying to use the sample code for a wordpress plugin from here https://github.com/YahnisElsts/wp-update-server - but I keep getting an error when checking for updates "Could not determine if updates are available for SJEV Test plugin. Failed to parse update metadata. Try validating your .json file with http://jsonlint.com/ puc-invalid-json"

Any ideas what could be causing this?

Thanks

from wp-update-server.

Try opening the metadata URL in your browser. What does the page say, if anything?

from wp-update-server.

how would I get the metadata url?

from wp-update-server.

Presumably, you already have it. It's the URL that you pass to the buildUpdateChecker() method.

from wp-update-server.

Oh I see, thanks! So it seems that my problem is that none of the wordpress functions are available when I access it with the url in this way. For example I get "Fatal error: Call to undefined function home_url() in /home/encoremedia/public_html/wp-content/plugins/sjev_plugin-server/sjev_plugin-server.php on line 31"

from wp-update-server.

It sounds like you might be accessing plugin PHP files directly instead of going through WordPress. You can do that - I've done it myself as a way to improve performance - but then you have to carefully design your plugin so that it works both inside WP and as a stand-alone script.

Are you sure you're using the right URL? When embedding the server in a plugin, the URL would typically be something like this:
https://example.com/?your_action_param=get_metadata&your_slug_param=plugin-slug

On the other hand, this would be incorrect:
https://example.com/wp-content/plugin-name/plugin-name.php?action=get_metadata&slug=plugin-slug

from wp-update-server.

That is exactly what I was doing! I had it working as a standalone script before and didn't update the url in the plugin. Thanks very much for your help. Working perfectly now.

from wp-update-server.