add events package (#2341)

* add events package

* update go version

events/store_test.go

@@ -0,0 +1,47 @@
+package events
+
+import (
+	"testing"
+
+	"github.com/google/uuid"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestStore(t *testing.T) {
+	store := NewStore()
+
+	testData := []Event{
+		{ID: uuid.New().String(), Topic: "foo"},
+		{ID: uuid.New().String(), Topic: "foo"},
+		{ID: uuid.New().String(), Topic: "bar"},
+	}
+
+	// write the records to the store
+	t.Run("Write", func(t *testing.T) {
+		for _, event := range testData {
+			err := store.Write(&event)
+			assert.Nilf(t, err, "Writing an event should not return an error")
+		}
+	})
+
+	// should not be able to read events from a blank topic
+	t.Run("ReadMissingTopic", func(t *testing.T) {
+		evs, err := store.Read("")
+		assert.Equal(t, err, ErrMissingTopic, "Reading a blank topic should return an error")
+		assert.Nil(t, evs, "No events should be returned")
+	})
+
+	// should only get the events from the topic requested
+	t.Run("ReadTopic", func(t *testing.T) {
+		evs, err := store.Read("foo")
+		assert.Nilf(t, err, "No error should be returned")
+		assert.Len(t, evs, 2, "Only the events for this topic should be returned")
+	})
+
+	// limits should be honoured
+	t.Run("ReadTopicLimit", func(t *testing.T) {
+		evs, err := store.Read("foo", ReadLimit(1))
+		assert.Nilf(t, err, "No error should be returned")
+		assert.Len(t, evs, 1, "The result should include no more than the read limit")
+	})
+}