VOL-2087 reorganize and unit test arouterd

Change-Id: Iadacd1829095e8ffde306e5ebf164f4d67196a68
diff --git a/internal/pkg/afrouterd/misc_test.go b/internal/pkg/afrouterd/misc_test.go
new file mode 100644
index 0000000..a07b9aa
--- /dev/null
+++ b/internal/pkg/afrouterd/misc_test.go
@@ -0,0 +1,100 @@
+/*
+ * Copyright 2018-present Open Networking Foundation
+
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+
+ * http://www.apache.org/licenses/LICENSE-2.0
+
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// This file implements an exit handler that tries to shut down all the
+// running servers before finally exiting. There are 2 triggers to this
+// clean exit thread: signals and an exit channel.
+
+package afrouterd
+
+import (
+	"github.com/stretchr/testify/assert"
+	"os"
+	"testing"
+)
+
+func TestGetIntEnv(t *testing.T) {
+
+	err := os.Setenv("testkey", "123")
+	assert.Nil(t, err)
+
+	defer func() { os.Unsetenv("testkey") }()
+
+	v := GetIntEnv("testkey", 0, 1000, 456)
+	assert.Equal(t, 123, v)
+
+	v = GetIntEnv("doesnotexist", 0, 1000, 456)
+	assert.Equal(t, 456, v)
+}
+
+func TestGetIntEnvTooLow(t *testing.T) {
+
+	err := os.Setenv("testkey", "-1")
+	assert.Nil(t, err)
+
+	defer func() { os.Unsetenv("testkey") }()
+
+	defer func() {
+		if r := recover(); r == nil {
+			t.Errorf("The code did not panic")
+		}
+	}()
+	_ = GetIntEnv("testkey", 0, 1000, 456)
+}
+
+func TestGetIntEnvTooHigh(t *testing.T) {
+
+	err := os.Setenv("testkey", "1001")
+	assert.Nil(t, err)
+
+	defer func() { os.Unsetenv("testkey") }()
+
+	defer func() {
+		if r := recover(); r == nil {
+			t.Errorf("The code did not panic")
+		}
+	}()
+	_ = GetIntEnv("testkey", 0, 1000, 456)
+}
+
+func TestGetIntEnvNotInteger(t *testing.T) {
+
+	err := os.Setenv("testkey", "stuff")
+	assert.Nil(t, err)
+
+	defer func() { os.Unsetenv("testkey") }()
+
+	defer func() {
+		if r := recover(); r == nil {
+			t.Errorf("The code did not panic")
+		}
+	}()
+	_ = GetIntEnv("testkey", 0, 1000, 456)
+}
+
+func TestGetStrEnv(t *testing.T) {
+
+	err := os.Setenv("testkey", "abc")
+	assert.Nil(t, err)
+
+	defer func() { os.Unsetenv("testkey") }()
+
+	v := GetStrEnv("testkey", "def")
+	assert.Equal(t, "abc", v)
+
+	v = GetStrEnv("doesnotexist", "def")
+	assert.Equal(t, "def", v)
+}