[CIS-1459] Make Data Formatters Configurable

[nuno-vieira]

🔗 Issue Link

CIS-1459
#1739

🎯 Goal

Provide a way to change the data formatting in the SDK.

🛠 Implementation

Expose all formatters in the Appearance configuration through the Appearance.default.formatters. Each formatter is represented by a Protocol so that the customer can provide their own implementation or change the default ones.

🎨 Changes

N/A

🧪 Testing

Example on how to change a default formatter:

let defaultTimestampFormatter = DefaultMessageTimestampFormatter()
defaultTimestampFormatter.dateFormatter.timeStyle = .medium
Appearance.default.formatters.messageTimestamp = defaultTimestampFormatter

Example on how to provide a custom formatter:

class CustomUserLastActivityFormatter: UserLastActivityFormatter {
    public lazy var dateFormatter: DateFormatter = {
        let formatter = DateFormatter()
        formatter.dateStyle = .short
        formatter.timeStyle = .short
        formatter.doesRelativeDateFormatting = true
        formatter.locale = .autoupdatingCurrent
        return formatter
    }()

    func format(_ date: Date) -> String? {
        "last active: " + dateFormatter.string(from: date)
    }
}
...
Appearance.default.formatters.userLastActivity = CustomUserLastActivityFormatter()

☑️ Checklist

• I have signed the Stream CLA (required)
• This change follows zero ⚠️ policy (required)
• Changelog is updated with client-facing changes

[codecov]

Codecov Report

Merging #1742 (84c64ae) into develop (fe82d44) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop    #1742   +/-   ##
========================================
  Coverage    85.39%   85.39%           
========================================
  Files          234      234           
  Lines        11247    11247           
========================================
  Hits          9604     9604           
  Misses        1643     1643           

Flag	Coverage Δ
llc-tests	85.39% <ø> (ø)

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Impacted Files	Coverage Δ
...treamChat/Models/Attachments/AttachmentTypes.swift	86.66% <ø> (ø)

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[tbarbugli]

We should add something to the SDK docs about this

[nuno-vieira]

We should add something to the SDK docs about this

Will add the docs once we define the final API 👍

[emerge-tools]

Congratulations! This change reduces app size by 1.6 MB

🗂 See the Emerge breakdown

Item	Size change
StreamChatUI.framework/StreamChatUI.GalleryVC.setUpAppearance	-56.3 kB
StreamChatUI.framework/StreamChatUI.ChatMessageActionControl.updateContent	-45.5 kB
StreamChatUI.framework/StreamChatUI.ChatMessageContentView.updateContent	-34.4 kB
StreamChatUI.framework/StreamChatUI.ChatChannelListItemView.setUpAppearance	-33.7 kB
StreamChatUI.framework/StreamChatUI.FileAttachmentView.setUpAppearance	-33.6 kB
StreamChatUI.framework/StreamChatUI.ChatMentionSuggestionView.setUpAppearance	-33.6 kB
StreamChatUI.framework/StreamChatUI.CommandLabelView.setUpAppearance	-28.9 kB
StreamChatUI.framework/StreamChatUI.ChatChannelListVC.swipeableViewActionViews(for)	-28.1 kB
StreamChatUI.framework/StreamChatUI.ChatMessageFileAttachmentListView.ItemView.setUpAppearance	-28.1 kB
StreamChatUI.framework/StreamChatUI.AttachmentActionButton.updateContent	-28.0 kB
StreamChatUI.framework/StreamChatUI.ChatChannelAvatarView.loadAvatarsFrom(urls,channelId,completion)	-22.5 kB
StreamChatUI.framework/StreamChatUI.VideoAttachmentComposerPreview.setUpAppearance	-22.5 kB
StreamChatUI.framework/StreamChatUI.ChatMessageLinkPreviewView.setUpAppearance	-22.4 kB
StreamChatUI.framework/StreamChatUI.ChatCommandSuggestionView.setUpAppearance	-22.4 kB
StreamChatUI.framework/StreamChatUI.TitleContainerView.setUpAppearance	-22.4 kB
StreamChatUI.framework/StreamChatUI.ChatSuggestionsHeaderView.setUpAppearance	-21.4 kB
StreamChatUI.framework/StreamChatUI.CheckboxControl.updateContent	-17.3 kB
StreamChatUI.framework/StreamChatUI.InputChatMessageView.setUpAppearance	-17.3 kB
StreamChatUI.framework/StreamChatUI.ChatChannelAvatarView.loadMergedAvatars(channel)	-16.9 kB
StreamChatUI.framework/StreamChatUI.ChatMessageReactionAuthorsVC.setUpAppearance	-16.9 kB

🔎 See the full analysis (84c64ae) merging into develop (fe82d44)

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[nuno-vieira]

Converted to draft, since there will be some team discussions on the API

[bielikb]

Great job @nuno-vieira. I left two doc suggestions

[nuno-vieira]

We should add something to the SDK docs about this

Docs are now available 👍

Docs are now part of the PR