Background Sync

[antonkorotkov]

The source: #523

Need to document:

• WP_STATELESS_MEDIA_UPLOAD_CHUNK_SIZE - if defined, the uploading will be done by chunks of the specified size in bytes. This helps in the case of Allocated memory exhausted errors.

New Constants:

• WP_STATELESS_SYNC_MAX_BATCH_SIZE - the maximum size of a batch of items to be saved in a single DB row. Int. Default 50.
• WP_STATELESS_SYNC_LOG - the path to the log file for the sync processes to put their log information. If not set - error_log configuration is used.
• WP_STATELESS_SYNC_HEALTHCHECK_INTERVAL - the sync healthcheck cron interval in minutes. The default is 1.

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Change Log

• NEW - Completely rewritten the synchronization tool. GitHub issue #523.
• FIX - Fixed an issue when original files were not deleted from the server in the Ephemeral mode. GitHub issue #484.
• FIX - Fixed an incorrect behavior of image srcset attribute in the Backup mode. GitHub issue #558.
• COMPATIBILITY - Litespeed Cache - Fixed an incorrect upload folder determination. GitHub issue #527.