--- title: Swift slug: v4-6/release-notes/swift icon: {"faIcon":"fa-brands fa-swift"} docTags: createdAt: 2024-03-07T16:11:53.187Z --- ![](https://api.archbee.com/api/optimize/qoRkNxW5fJ81r_NqVpc8C/tgePnXO58H3mU6zWvtqNX_swift-card-light-mode.png) # 4.6 Version Release ::::ExpandableHeading ### Added: Support for runtime configuration using DQL Ditto introduced an experimental feature for retrieving, configuring, and restoring default configurations for the Ditto peer-to-peer system at runtime using Ditto Query Language (DQL) syntax. :::hint{type="info"} The Customer Experience team offers this feature to customers when appropriate for your scenario and use case. ::: Through two new statements:`ALTER SYSTEM` and `SHOW`, you can change parameters, settings, and configurations while your peer-to-peer system is actively running. :::: :::ExpandableHeading ### Fixed: Accumulation of unsubscribed documents Due to recent improvements to the sync protocol, Small peers no longer accumulate unsubscribed documents when subscription statuses are changed. This fix ensures that the peer-to-peer system prevents retaining unnecessary data, resulting in optimized resource usage. ::: :::ExpandableHeading ### Changed: Sync protocol to streamline the sync process Ditto's recent adjustments to the sync protocol have decreased the exchange of redundant data during re-synchronization, improving the efficiency and stability of the sync process. ::: :::ExpandableHeading ### Changed: Sync protocol so peers use the latest version Ditto decoupled sync protocol from conflict-free replicated data types (CRDTs) so peers now prioritize using the latest supported protocol version for data exchange. Even if your app uses legacy CRDTs, you'll benefit from this backward-compatible change. ::: :::ExpandableHeading ### Improved: API reference for `sort()` method The documentation for the `sort()` API method on cursor operations has been updated to provide clearer explanations of behavior in cases where the specified field for sorting is missing. ::: :::ExpandableHeading ### Improved: Parser error messages Now, parser error messages focus more on indicating the location of errors within the input code, rather than suggesting potential fixes. With this improvement to the API reference, you have better guidance in debugging your code. ::: :::ExpandableHeading ### Fixed: An issue where Ditto Link could enter an infinite loop This fix addresses a specific bug where Ditto Link could go into a "forever loop" under certain conditions. This loop, caused performance issues and could potentially lead your app crashing. ::: :::ExpandableHeading ### Fixed: Inconsistent handling of legacy query-builder APIs Before this fix, there were issues with incorrect casting to `boolean` values, leading to inconsistent behavior. This update ensures that values are cast properly, resulting in consistency across your app. ::: :::ExpandableHeading ### Added: Comparison operations for legacy query-builder APIs If you're using legacy CRDTs in your app, now you can perform comparisons with `ATTACHMENT` objects. ::: :::ExpandableHeading ### Fixed: Limitation in fetching attachment tokens Previously, DQL queries were limited in their ability to retrieve the pointer that Ditto uses to fetch your `ATTACHMENT` object. Now you can query the following additional fields to improve query capabilities: | **Detail** | **Description** | | ------------- | ------------------------------------------------------------------------------------------------------ | | Attachment ID | A cryptographic hash of the attachment's contents. (See Organizing by ID and Attachment Token) | | Metadata | Additional information about the attachment, such as its name, type, and so on. (See Attachment Token) | | Blob Length | The size of the blob data in terms of length (`len`) in bytes. (See Blob Store) | Following is an example document showing the fields added in this release: ```json { "_id": "abc123", "make": "Hyundai", "year": 2018, "color": "black", "picture": { "id": "", "metadata": { "mime_type": "image/jpeg", "name": "car_stock_photo.jpg", }, "len": 123 } } ``` ::: :::ExpandableHeading ### Fixed: Error handling when creating an `ATTACHMENT` We've improved error handling mechanisms to manage input-output (IO) errors that may result during the creation of `ATTACHMENT` objects. Now you'll receive clearer feedback when encountering errors so you can prevent potential crashes and improve the overall stability of your app. ::: :::ExpandableHeading ### Fixed: Internal data-decoding functions Fixed: Improved internal data decoding functions to prevent API crashes under certain inputs: We've improved the software component for handling tasks such as byte parsing, character decoding, and data type conversion. Instead of crashing, like before, the API returns an error. ::: :::ExpandableHeading ### Fixed: Issues causing crashes when preparing to sync There were issues causing app crashes during the preparation phase for syncing data to remote peers. With these improvements, the likelihood of encountering errors during syncing has been significantly reduced. ::: :::ExpandableHeading ### Added: Replacement for deprecated `getData()` method Now, when accessing attachments, use the new `data()` API method on `DittoAttachment`. ::: :::ExpandableHeading ### Added: `JSONDecoder` functionality for `DittoQueryResultItem` class We've added the `jsonData()` method that, once invoked, returns a `Data` object that you can use to integrate the results into your JSON decoding workflows. ::: :::ExpandableHeading ### Added: `fetchAttachment()` and `fetchAttachmentPublisher()` These new variants accept an attachment token dictionary representation provided by the value of `DittoQueryResultItem`. ::: :::ExpandableHeading ### Added: Replacement `DittoStore` class for working with attachments Previously, you'd create attachments using a method in the `DittoCollection` class, which has since been deprecated. **New Method for Creating Attachments** This release rolls out a replacement `DittoStore` class with a new API method for creating `ATTACHMENT` objects: `newAttachment()` This new way of creating attachments comes with improvements, such as asynchronous execution. Meaning, it does not block your main thread. **New Property for Managing Fetching** With the `attachmentFetchers` property, keep track of ongoing attachment fetching operations. **New Mechanism for Handling Fetching-Related Errors** If there are any issues fetching attachments, the `fetchAttachment()` method now throws `DittoError`. **New Document Field Properties for Identifying Attachments** The following new properties that you can query to increase the efficiency of fetching operations: | **Property** | **Description** | | ------------ | -------------------------------------------------------------------------------- | | `id` | A cryptographic hash of the attachment's contents. | | `metadata` | Additional information about the attachment, such as its name, type, and so on. | | `len` | The size of the blob data in terms of length (`len`) in bytes. | **New Method for Retrieving Length of Attachments** The `getLength()` method provides a way to determine how large an attachment is in terms of its bytes. ::: :::ExpandableHeading ### Changed: Log level for `DittoCollection` class (deprecated) Calls made to the `newAttachment()` method on the recently deprecated `DittoCollection` class now log at the `error` log level. ::: :::ExpandableHeading ### Fixed: Issue related to attachment token schema We fixed an issue related to the structure representing attachment tokens provided by the `value` of `DittoQueryResultItem` so that the schema accurately represents the content of attachment tokens. The token is now provided as a dictionary of the form `["id": "...", "len": 123, "metadata": ...]` where `metadata` is a `` dictionary[String: String]` ``. ::: :::ExpandableHeading ### Fixed: Issues related to the presence graph There was an issue where `DittoPresence.GraphPublisher` and `Ditto.RemotePeersPublisher` (deprecated) sent data to a subscribing peer before they were ready to receive it. ::: :::ExpandableHeading ### (Experimental) Fixed: Issue with mutual-link connections Two peers targeting each other simultaneously in Ditto Bus or Query Overlap Groups, known as *mutual-link connections*, no longer struggle to establish a multihop connection to participate in the flood-fill process. :::