Service Design Specification - Object Design for listingImage

clonesahibinden-listingimage-service documentation

Document Overview

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

listingImage Data Object

Object Overview

Description: Stores metadata about each image attached to a classified listing, with enforced image count, format, size, and dimension constraints. Four separate URL fields for different resolutions. Tied to listing; managed by listing owner/admin/mod.

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: doUpdate

The existing record will be updated with the new data.No error will be thrown.

Properties Schema

Property Type Required Description
fileSize Integer Yes Size of the image file in bytes.
fullUrl String Yes URL to a full-res processed but possibly optimized image (e.g. with max side 1600px, for gallery display).
height Float Yes Height of the original image, in pixels.
listingId ID Yes The related listing that this image belongs to.
mediumUrl String Yes URL to the medium-sized processed image version (e.g. 400x300px or similar).
mimeType String Yes MIME type of the image (e.g., image/jpeg, image/png, image/webp, image/gif).
sortOrder Integer Yes Order value for display in UI; the lowest value image is the cover/main image.
thumbnailUrl String Yes URL to the thumbnail image (small size, e.g. 120x90px).
uploadedAt Date Yes UTC timestamp when image was uploaded to platform.
url String Yes URL to the original uploaded image file (full resolution/original).
width Float Yes Width of the original image, in pixels.

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.

Constant Properties

fileSize fullUrl height listingId mediumUrl mimeType thumbnailUrl uploadedAt url width

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

fileSize fullUrl height listingId mediumUrl mimeType sortOrder thumbnailUrl url width

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.

Elastic Search Indexing

listingId sortOrder uploadedAt url

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

listingId sortOrder

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.

Cache Select Properties

listingId

Cache select properties are used to collect data from Redis entity cache with a different key than the data object id. This allows you to cache data that is not directly related to the data object id, but a frequently used filter.

Relation Properties

listingId

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

Filter Properties

listingId

Filter properties are used to define parameters that can be used in query filters, allowing for dynamic data retrieval based on user input or predefined criteria. These properties are automatically mapped as API parameters in the listing API’s that have “Auto Params” enabled.