Fatal error: Declaration of Algolia\AlgoliaSearch\Http\Psr7\Uri::withScheme(string $scheme): Psr\Http\Message\UriInterface must be compatible with Psr\Http\Message\UriInterface::withScheme($scheme)

Confirming I'm running into this issue as well.

I downgraded to algolia/algoliasearch-client-php:3.3.2 to resolve the issue. The implementation of typing is not lining up with the UriInterface declaration. I'm okay to do this for now. Doesn't seem like a problem for this module, but moreso with the UriInterface.

I bumped into the same problem (Drupal 9.5.10/PHP 8.1). Just like josh.stewart, switching to 3.3.x sorted it out for me. Here's how I did it: composer require algolia/algoliasearch-client-php:~3.3.2

The culprit behind the need to roll back is the psr/http-message dependency. From what I can tell, Drupal 9.5x blocks updating to a version that would fix this.

Same here, but in cron, downgrading the algolia search client to 3.3.2 fixes it

[INFO] [cron] [2023-09-07T10:32:56] Starting execution of search_api_cron(), execution of purge_processor_cron_cron() took 39.31ms. | uid: 0 | request-uri: http://default/ | refer:  | ip:  127.0.0.1 | link: 
PHP Fatal error:  Declaration of Algolia\AlgoliaSearch\Http\Psr7\Uri::withScheme(string $scheme): Psr\Http\Message\UriInterface must be compatible with Psr\Http\Message\UriInterface::withScheme($scheme) in /var/www/vendor/algolia/algoliasearch-client-php/src/Http/Psr7/Uri.php on line 439
 [warning] Drush command terminated abnormally.

We just updated algolia/algoliasearch-client-php from 3.3.2 to 3.4.0 and this error appears.

Yeah the error is caused by an update to the client to v3.4, which according to https://github.com/algolia/algoliasearch-client-php/issues/720 is not an official or supported release yet. This might require a more specific version constraint in this module to prevent the error.

This fixed the issue for me, without needing to lock a specific version of algolia/algoliasearch-client-php:

• composer remove drupal/core-recommended (make sure drupal/core is installed instead)
• composer update algolia/algoliasearch-client-php psr/http-message

Looks like this issue is only present in Drupal 9: drupal/core-recommended:9.5.11 has a dependency on psr/http-message:~1.0.1, Drupal 10 does not have a dependency on psr/http-message.

The best solution to me seems to add a conflict on algolia/algoliasearch-client-php:>3.3.2 to composer.json, and to remove it again once a release of this module comes out that drops support for Drupal 9.