jikan-rest/TROUBLESHOOTING.md

# Troubleshooting Guide

## My local instance keeps returning HTTP 500

First off, check `storage/logs/lumen.log`.

**1. If you're getting a lot of Redis errors along the lines of `BGSAVE` failing.**
You probably have a low RAM resource, switch over to file caching `CACHE_DRIVER=file`.

Redis throws this error even if you have about 1/4 of your RAM free. This is because it does a background save of your entire Redis cache - which is stored in-memory and which fails without the sufficient required memory.

You can stop Redis from haggling you and override that by running the following command: `redis-cli config set stop-writes-on-bgsave-error`

**2. Jikan is failing to cache (when `CACHE_DRIVER=file`) because the "disk is out of space" - but you're sure you have enough space available.**

Sorry! This is due to a bug on a previous release ([Issue #59](https://github.com/jikan-me/jikan-rest/issues/59)), please make sure you're upto date.

**Recovery Procedure**
- `sudo service supervisor stop`
- Delete Lumen & worker logs: `rm storage/logs/lumen.log` + `rm storage/logs/worker.log`
- Run `lsof | grep deleted` to check for the "Lumen.log" process, you'll know when it has a bizzare amount of space allocated to the process to it. Copy the process ID and then kill it; `kill [process id]` e.g `kill 12345`
- Make sure your Jikan instance is on the latest release. Run a `git pull` and then `composer update`
- Reduce the number of supervisor processes in `/etc/supervisor/conf.d/jikan-worker.conf` e.g `numprocs=1`

And then reload the supervisor configuration:

`sudo service supervisor start`

`sudo supervisorctl reread`

`sudo supervisorctl reload`

`sudo supervisorctl update`

`sudo supervisorctl start jikan-worker:*`

- Restart everything:
`sudo service supervisor restart`

`sudo service apache2 restart`

`sudo service redis restart`

If Redis is taking too long to restart, follow this: https://stackoverflow.com/a/45069100/2326811 and then start it `sudo service redis start`


## I want to clear the cache in Jikan
`php artisan cache:clear`

## I want to clear the Cache Updater Queue

1. `redis-cli --scan --pattern queue_update:* | xargs redis-cli del` or alternatively replace `del` with `unlink` to have it done in the background ([Redis 4.0.0 required](https://redis.io/commands/unlink))

2. `php artisan queue:restart`

3. `sudo service supervisor restart`


More troubleshooting Q/A on the way, please let me know if there's anything else I should add onto here.