WIP: add tests for logging

Co-authored-by: James Mead <james.mead@gofreerange.com>

Author: chrislo

spec/models/immunisation_import_spec.rb

@@ -51,6 +51,14 @@
     create(:gias_school, urn: "100000")
   end
 
+  around do |example|
+    appender = SemanticLogger.add_appender(io: semantic_logger_io, formatter: :json)
+    example.run
+  ensure
+    SemanticLogger.remove_appender(appender)
+  end
+
+  let(:semantic_logger_io) { StringIO.new }
   let(:programmes) { [Programme.flu] }
   let(:team) do
     if type == "national_reporting"
@@ -77,6 +85,27 @@
 
   it_behaves_like "a CSVImportable model"
 
+  describe ".create" do
+    it "a tagged message containing the started_at time of the import" do
+      import = immunisation_import
+
+      SemanticLogger.flush
+      semantic_logger_io.rewind
+
+      log_lines = semantic_logger_io.read.split("\n")
+      tagged_lines = log_lines.map {|l| JSON.parse(l) }.select do |j|
+        j['named_tags'] == { 'import_class' => 'ImmunisationImport', 'import_id' => import.id }
+      end
+
+      expect(tagged_lines.size).to eq(1)
+      expect(tagged_lines.first).to include('message' => 'started')
+
+      payload = tagged_lines.first['payload']
+      started_at = Time.zone.parse(payload['started_at'])
+      expect(started_at.to_i).to eq(import.created_at.to_i)
+    end
+  end
+
   describe "validations" do
     subject { unsaved_import }