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/testing.go

@@ -0,0 +1,128 @@
+package main
+
+import (
+	"fmt"
+	"github.com/op/go-logging"
+	"os"
+	"testing"
+)
+
+func failTestOnError(t *testing.T, err error) {
+	if err != nil {
+		t.Errorf("failed test: %v", err)
+	}
+}
+
+func getPublicTables() ([]string, error) {
+	statement := `
+    SELECT tablename
+    FROM pg_tables
+    WHERE schemaname='public';
+  `
+	rows, err := db.Query(statement)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "cannot query public tables: %v", err)
+		return []string{}, err
+	}
+
+	defer rows.Close()
+
+	tables := []string{}
+	for rows.Next() {
+		var table string
+		if err = rows.Scan(&table); err != nil {
+			fmt.Fprintf(os.Stderr, "cannot scan table name: %v", err)
+			return []string{}, err
+		}
+
+		tables = append(tables, table)
+	}
+
+	return tables, nil
+}
+
+func dropTables() error {
+	tables, err := getPublicTables()
+	if err != nil {
+		return err
+	}
+
+	for _, table := range tables {
+		if table != "migrations" {
+			_, err = db.Exec(fmt.Sprintf("DROP TABLE %s;", table))
+			if err != nil {
+				fmt.Fprintf(os.Stderr, "cannot drop %s: %v", table, err)
+				return err
+			}
+		}
+	}
+
+	return nil
+}
+
+func setupTestDatabase() error {
+	os.Setenv("POSTGRES", "postgres://postgres:postgres@0.0.0.0/commento_test?sslmode=disable")
+
+	if err := connectDB(); err != nil {
+		return err
+	}
+
+	if err := dropTables(); err != nil {
+		return err
+	}
+
+	if err := performMigrationsFromDir("../db/"); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func clearTables() error {
+	tables, err := getPublicTables()
+	if err != nil {
+		return err
+	}
+
+	for _, table := range tables {
+		_, err = db.Exec(fmt.Sprintf("DELETE FROM %s;", table))
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "cannot clear %s: %v", table, err)
+			return err
+		}
+	}
+
+	return nil
+}
+
+var setupComplete bool
+
+func setupTestEnv() error {
+	if !setupComplete {
+		setupComplete = true
+
+		if err := createLogger(); err != nil {
+			return err
+		}
+
+		// Print messages to console only if verbose. Sounds like a good idea to
+		// keep the console clean on `go test`.
+		if !testing.Verbose() {
+			logging.SetLevel(logging.CRITICAL, "")
+		}
+
+		if err := setupTestDatabase(); err != nil {
+			return err
+		}
+
+		if err := createMarkdownRenderer(); err != nil {
+			return err
+		}
+	}
+
+	if err := clearTables(); err != nil {
+		return err
+	}
+
+	return nil
+}