api: Add go files

I know this is a huge commit, but I can't be bothered to check
this in part by part.

api/commenter_get_test.go

@@ -0,0 +1,61 @@
+package main
+
+import (
+	"testing"
+)
+
+func TestCommenterGetByHexBasics(t *testing.T) {
+	failTestOnError(t, setupTestEnv())
+
+	commenterHex, _ := commenterNew("test@example.com", "Test", "undefined", "https://example.com/photo.jpg", "google")
+
+	c, err := commenterGetByHex(commenterHex)
+	if err != nil {
+		t.Errorf("unexpected error getting commenter by hex: %v", err)
+		return
+	}
+
+	if c.Name != "Test" {
+		t.Errorf("expected name=Test got name=%s", c.Name)
+		return
+	}
+}
+
+func TestCommenterGetByHexEmpty(t *testing.T) {
+	failTestOnError(t, setupTestEnv())
+
+	if _, err := commenterGetByHex(""); err == nil {
+		t.Errorf("expected error not found getting commenter with empty hex")
+		return
+	}
+}
+
+func TestCommenterGetBySession(t *testing.T) {
+	failTestOnError(t, setupTestEnv())
+
+	commenterHex, _ := commenterNew("test@example.com", "Test", "undefined", "https://example.com/photo.jpg", "google")
+
+	session, _ := commenterSessionNew()
+
+	commenterSessionUpdate(session, commenterHex)
+
+	c, err := commenterGetBySession(session)
+	if err != nil {
+		t.Errorf("unexpected error getting commenter by hex: %v", err)
+		return
+	}
+
+	if c.Name != "Test" {
+		t.Errorf("expected name=Test got name=%s", c.Name)
+		return
+	}
+}
+
+func TestCommenterGetBySessionEmpty(t *testing.T) {
+	failTestOnError(t, setupTestEnv())
+
+	if _, err := commenterGetBySession(""); err == nil {
+		t.Errorf("expected error not found getting commenter with empty session")
+		return
+	}
+}