Safe Loading Fields

Safe loading is a flag that you can use when non-redis resource cant be load from anywhere. If a field must have specific resources to load it, but you still want to use the models, for example, storing type that is stored in a specific service (not every can use it in you infrastructure).

Basic Usage

from typing import Optional
from rapyer import AtomicRedisModel
from rapyer.fields import SafeLoad

class Plugin(AtomicRedisModel):
    handler_class: SafeLoad[Optional[type]] = None
    name: str

Model-Wide Configuration

For models with many such fields, enable it globally:

from rapyer import AtomicRedisModel
from rapyer.config import RedisConfig

class DynamicConfig(AtomicRedisModel):
    Meta = RedisConfig(safe_load_all=True)

    type_field: Optional[type] = None  # Automatically safe
    name: str = "default"  # Not affected (already serializable)

Checking What Failed

After loading, check which fields couldn't be restored:

plugin = await Plugin.aget("plugin-123")

if plugin.failed_fields:
    print(f"Could not load: {plugin.failed_fields}")
    # Use a fallback
    plugin.handler_class = DefaultHandler

Example: Plugin System

class Plugin(AtomicRedisModel):
    handler: SafeLoad[Optional[type]] = None
    name: str

async def load_plugin(plugin_id: str):
    plugin = await Plugin.aget(plugin_id)

    if "handler" in plugin.failed_fields:
        return DefaultHandler()

    return plugin.handler() if plugin.handler else DefaultHandler()

Things to Know

• Always use Optional - the field can become None if loading fails
• Check failed_fields - know when something went wrong
• Warnings are logged - configure logging.getLogger("rapyer") to see them

Behavior Differences

Safe loading behaves differently depending on the field type:

• Model fields - when a field cannot be deserialized, it is set to None and tracked in failed_fields
• Collection fields (RedisList, RedisDict) - items that cannot be deserialized are skipped entirely (not included in the result)