Before this patch, if you called json_schema() for the same object across multiple threads at the same time, you would (sometimes!) get a SchemaError about None is not of type 'object', 'boolean' with references to schema['definitions']. The fix is to create a global lock around all writes to _schema, with checks for the happy path to avoid hitting the lock too frequently.
Some fixes to provide thread safety in hologram.
Before this patch, if you called
json_schema()for the same object across multiple threads at the same time, you would (sometimes!) get aSchemaErroraboutNone is not of type 'object', 'boolean'with references toschema['definitions']. The fix is to create a global lock around all writes to_schema, with checks for the happy path to avoid hitting the lock too frequently.