Add Keybase integration (#10297)

* create account_identity_proofs table

* add endpoint for keybase to check local proofs

* add async task to update validity and liveness of proofs from keybase

* first pass keybase proof CRUD

* second pass keybase proof creation

* clean up proof list and add badges

* add avatar url to keybase api

* Always highlight the “Identity Proofs” navigation item when interacting with proofs.

* Update translations.

* Add profile URL.

* Reorder proofs.

* Add proofs to bio.

* Update settings/identity_proofs front-end.

* Use `link_to`.

* Only encode query params if they exist.

URLs without params had a trailing `?`.

* Only show live proofs.

* change valid to active in proof list and update liveness before displaying

* minor fixes

* add keybase config at well-known path

* extremely naive feature flagging off the identity proof UI

* fixes for rubocop

* make identity proofs page resilient to potential keybase issues

* normalize i18n

* tweaks for brakeman

* remove two unused translations

* cleanup and add more localizations

* make keybase_contacts an admin setting

* fix ExternalProofService my_domain

* use Addressable::URI in identity proofs

* use active model serializer for keybase proof config

* more cleanup of keybase proof config

* rename proof is_valid and is_live to proof_valid and proof_live

* cleanup

* assorted tweaks for more robust communication with keybase

* Clean up

* Small fixes

* Display verified identity identically to verified links

* Clean up unused CSS

* Add caching for Keybase avatar URLs

* Remove keybase_contacts setting

app/lib/proof_provider/keybase/verifier.rb

@@ -0,0 +1,62 @@
+# frozen_string_literal: true
+
+class ProofProvider::Keybase::Verifier
+  def initialize(local_username, provider_username, token)
+    @local_username    = local_username
+    @provider_username = provider_username
+    @token             = token
+  end
+
+  def valid?
+    request = Request.new(:get, "#{ProofProvider::Keybase::BASE_URL}/_/api/1.0/sig/proof_valid.json", params: query_params)
+
+    request.perform do |res|
+      json = Oj.load(res.body_with_limit, mode: :strict)
+
+      if json.is_a?(Hash)
+        json.fetch('proof_valid', false)
+      else
+        false
+      end
+    end
+  rescue Oj::ParseError, HTTP::Error, OpenSSL::SSL::SSLError
+    false
+  end
+
+  def on_success_path(user_agent = nil)
+    url = Addressable::URI.parse("#{ProofProvider::Keybase::BASE_URL}/_/proof_creation_success")
+    url.query_values = query_params.merge(kb_ua: user_agent || 'unknown')
+    url.to_s
+  end
+
+  def status
+    request = Request.new(:get, "#{ProofProvider::Keybase::BASE_URL}/_/api/1.0/sig/proof_live.json", params: query_params)
+
+    request.perform do |res|
+      raise ProofProvider::Keybase::UnexpectedResponseError unless res.code == 200
+
+      json = Oj.load(res.body_with_limit, mode: :strict)
+
+      raise ProofProvider::Keybase::UnexpectedResponseError unless json.is_a?(Hash) && json.key?('proof_valid') && json.key?('proof_live')
+
+      json
+    end
+  rescue Oj::ParseError, HTTP::Error, OpenSSL::SSL::SSLError
+    raise ProofProvider::Keybase::UnexpectedResponseError
+  end
+
+  private
+
+  def query_params
+    {
+      domain: domain,
+      kb_username: @provider_username,
+      username: @local_username,
+      sig_hash: @token,
+    }
+  end
+
+  def domain
+    Rails.configuration.x.local_domain
+  end
+end