Gab Social. All are welcome.

app/lib/activitypub/adapter.rb

@@ -0,0 +1,66 @@
+# frozen_string_literal: true
+
+class ActivityPub::Adapter < ActiveModelSerializers::Adapter::Base
+  NAMED_CONTEXT_MAP = {
+    activitystreams: 'https://www.w3.org/ns/activitystreams',
+    security: 'https://w3id.org/security/v1',
+  }.freeze
+
+  CONTEXT_EXTENSION_MAP = {
+    manually_approves_followers: { 'manuallyApprovesFollowers' => 'as:manuallyApprovesFollowers' },
+    sensitive: { 'sensitive' => 'as:sensitive' },
+    hashtag: { 'Hashtag' => 'as:Hashtag' },
+    moved_to: { 'movedTo' => { '@id' => 'as:movedTo', '@type' => '@id' } },
+    also_known_as: { 'alsoKnownAs' => { '@id' => 'as:alsoKnownAs', '@type' => '@id' } },
+    emoji: { 'toot' => 'http://joinmastodon.org/ns#', 'Emoji' => 'toot:Emoji' },
+    featured: { 'toot' => 'http://joinmastodon.org/ns#', 'featured' => { '@id' => 'toot:featured', '@type' => '@id' } },
+    property_value: { 'schema' => 'http://schema.org#', 'PropertyValue' => 'schema:PropertyValue', 'value' => 'schema:value' },
+    atom_uri: { 'ostatus' => 'http://ostatus.org#', 'atomUri' => 'ostatus:atomUri' },
+    conversation: { 'ostatus' => 'http://ostatus.org#', 'inReplyToAtomUri' => 'ostatus:inReplyToAtomUri', 'conversation' => 'ostatus:conversation' },
+    focal_point: { 'toot' => 'http://joinmastodon.org/ns#', 'focalPoint' => { '@container' => '@list', '@id' => 'toot:focalPoint' } },
+    identity_proof: { 'toot' => 'http://joinmastodon.org/ns#', 'IdentityProof' => 'toot:IdentityProof' },
+    blurhash: { 'toot' => 'http://joinmastodon.org/ns#', 'blurhash' => 'toot:blurhash' },
+  }.freeze
+
+  def self.default_key_transform
+    :camel_lower
+  end
+
+  def self.transform_key_casing!(value, _options)
+    ActivityPub::CaseTransform.camel_lower(value)
+  end
+
+  def serializable_hash(options = nil)
+    options         = serialization_options(options)
+    serialized_hash = serializer.serializable_hash(options)
+    serialized_hash = self.class.transform_key_casing!(serialized_hash, instance_options)
+
+    { '@context' => serialized_context }.merge(serialized_hash)
+  end
+
+  private
+
+  def serialized_context
+    context_array = []
+
+    serializer_options = serializer.send(:instance_options) || {}
+    named_contexts     = [:activitystreams] + serializer._named_contexts.keys + serializer_options.fetch(:named_contexts, {}).keys
+    context_extensions = serializer._context_extensions.keys + serializer_options.fetch(:context_extensions, {}).keys
+
+    named_contexts.each do |key|
+      context_array << NAMED_CONTEXT_MAP[key]
+    end
+
+    extensions = context_extensions.each_with_object({}) do |key, h|
+      h.merge!(CONTEXT_EXTENSION_MAP[key])
+    end
+
+    context_array << extensions unless extensions.empty?
+
+    if context_array.size == 1
+      context_array.first
+    else
+      context_array
+    end
+  end
+end