Service Design Specification - Object Design for message

airbnb-messaging-service documentation

Document Overview

This document outlines the object design for the message model in our application. It includes details about the model’s attributes, relationships, and any specific validation or business logic that applies.

message Data Object

Object Overview

Description: Single message within a thread (text/media/system). Includes metadata for flagging/moderation. Linked to sender, thread, and content type.

This object represents a core data structure within the service and acts as the blueprint for database interaction, API generation, and business logic enforcement. It is defined using the ObjectSettings pattern, which governs its behavior, access control, caching strategy, and integration points with other systems such as Stripe and Redis.

Core Configuration

Composite Indexes

The index also defines a conflict resolution strategy for duplicate key violations.

When a new record would violate this composite index, the following action will be taken:

On Duplicate: doInsert

The new record will be inserted without checking for duplicates. This means that the composite index is designed for search purposes only.

Properties Schema

Property Type Required Description
threadId ID Yes -
content Text Yes -
senderId ID Yes -
sentAt Date Yes -
messageType Enum Yes -
mediaUrl String No -
isModerated Boolean Yes -
isFlagged Boolean Yes -
flaggedBy ID No -
flagReason String No -
isRead Boolean Yes -

Default Values

Default values are automatically assigned to properties when a new object is created, if no value is provided in the request body. Since default values are applied on db level, they should be literal values, not expressions.If you want to use expressions, you can use transposed parameters in any business API to set default values dynamically.

Always Create with Default Values

Some of the default values are set to be always used when creating a new object, even if the property value is provided in the request body. It ensures that the property is always initialized with a default value when the object is created.

Constant Properties

threadId senderId sentAt messageType

Constant properties are defined to be immutable after creation, meaning they cannot be updated or changed once set. They are typically used for properties that should remain constant throughout the object’s lifecycle. A property is set to be constant if the Allow Update option is set to false.

Auto Update Properties

threadId content senderId messageType mediaUrl isModerated isFlagged flaggedBy flagReason isRead

An update crud API created with the option Auto Params enabled will automatically update these properties with the provided values in the request body. If you want to update any property in your own business logic not by user input, you can set the Allow Auto Update option to false. These properties will be added to the update API’s body parameters and can be updated by the user if any value is provided in the request body.

Enum Properties

Enum properties are defined with a set of allowed values, ensuring that only valid options can be assigned to them. The enum options value will be stored as strings in the database, but when a data object is created an addtional property with the same name plus an idx suffix will be created, which will hold the index of the selected enum option. You can use the index property to sort by the enum value or when your enum options represent a sequence of values.

Elastic Search Indexing

threadId senderId sentAt messageType isModerated isFlagged isRead

Properties that are indexed in Elastic Search will be searchable via the Elastic Search API. While all properties are stored in the elastic search index of the data object, only those marked for Elastic Search indexing will be available for search queries.

Database Indexing

threadId senderId

Properties that are indexed in the database will be optimized for query performance, allowing for faster data retrieval. Make a property indexed in the database if you want to use it frequently in query filters or sorting.

Relation Properties

threadId senderId flaggedBy

Mindbricks supports relations between data objects, allowing you to define how objects are linked together. You can define relations in the data object properties, which will be used to create foreign key constraints in the database. For complex joins operations, Mindbricks supportsa BFF pattern, where you can view dynamic and static views based on Elastic Search Indexes. Use db level relations for simple one-to-one or one-to-many relationships, and use BFF views for complex joins that require multiple data objects to be joined together.

The target object is a parent object, meaning that the relation is a one-to-many relationship from target to this object.

On Delete: Set Null Required: Yes

The target object is a parent object, meaning that the relation is a one-to-many relationship from target to this object.

On Delete: Set Null Required: Yes

The target object is a parent object, meaning that the relation is a one-to-many relationship from target to this object.

On Delete: Set Null Required: No