[Asp.net 5] Configuration-新一代的配置文件（ConfigurationSource的多种实现）

关于配置文件的目录：[Asp.net 5] Configuration-新一代的配置文件

在前面我们介绍了，系统中用IConfigurationSource表示不同配置文件的来源，起到读取、设置、加载配置文件的作用。而虚拟类ConfigurationSource继承接口IConfigurationSource，其他类又由ConfigurationSource派生（当然我们也可以写继承自接口IConfigurationSource类，但是没什么必要）。下面是实现不同配置方式的工程：

下面我们主要以测试用例的方式讲解Json与XMl配置文件的源码以及实用方式：

Microsoft.Framework.Configuration.Json

Json的配置文件：在实现的过程中使用Newtonsoft.Json的NuGet程序包，这是非常有名的json操作组件，如果单独涉及到.net的Json操作，推荐使用该组件。

• Json包含数组的使用：

public void ArrayOfObjects()
        {
            var json = @"{
                'ip': [
                    {
                        'address': '1.2.3.4',
                        'hidden': false
                    },
                    {
                        'address': '5.6.7.8',
                        'hidden': true
                    }
                ]
            }";

            var jsonConfigSource = new JsonConfigurationSource(TestStreamHelpers.ArbitraryFilePath);
            jsonConfigSource.Load(TestStreamHelpers.StringToStream(json));

            Assert.Equal("1.2.3.4", jsonConfigSource.Get("ip:0:address"));
            Assert.Equal("False", jsonConfigSource.Get("ip:0:hidden"));
            Assert.Equal("5.6.7.8", jsonConfigSource.Get("ip:1:address"));
            Assert.Equal("True", jsonConfigSource.Get("ip:1:hidden"));
        }

• json多配置文件的使用：

public void ExplicitArrayReplacement()
        {
            var json1 = @"{
                'ip': [
                    '1.2.3.4',
                    '7.8.9.10',
                    '11.12.13.14'
                ]
            }";

            var json2 = @"{
                'ip': {
                    '1': '15.16.17.18'
                }
            }";

            var jsonConfigSource1 = new JsonConfigurationSource(TestStreamHelpers.ArbitraryFilePath);
            jsonConfigSource1.Load(TestStreamHelpers.StringToStream(json1));

            var jsonConfigSource2 = new JsonConfigurationSource(TestStreamHelpers.ArbitraryFilePath);
            jsonConfigSource2.Load(TestStreamHelpers.StringToStream(json2));

            var builder = new ConfigurationBuilder();
            builder.Add(jsonConfigSource1, load: false);
            builder.Add(jsonConfigSource2, load: false);
            var config = builder.Build();

            Assert.Equal(3, config.GetConfigurationSections("ip").Count());
            Assert.Equal("1.2.3.4", config.Get("ip:0"));
            Assert.Equal("15.16.17.18", config.Get("ip:1"));
            Assert.Equal("11.12.13.14", config.Get("ip:2"));
        }

• 配置文件的排序后顺序（获取所有子key的时候会对key值进行排序）

public void PropertiesAreSortedByNumberOnlyFirst()
        {
            var json = @"{
                'setting': {
                    'hello': 'a',
                    'bob': 'b',
                    '42': 'c',
                    '4':'d',
                    '10': 'e',
                    '1text': 'f',
                }
            }";

            var jsonConfigSource = new JsonConfigurationSource(TestStreamHelpers.ArbitraryFilePath);
            jsonConfigSource.Load(TestStreamHelpers.StringToStream(json));

            var builder = new ConfigurationBuilder();
            builder.Add(jsonConfigSource, load: false);
            var config = builder.Build();

            var configurationSection = config.GetConfigurationSection("setting");
            var indexConfigurationSections = configurationSection.GetConfigurationSections().ToArray();

            Assert.Equal(6, indexConfigurationSections.Count());
            Assert.Equal("4", indexConfigurationSections[0].Key);
            Assert.Equal("10", indexConfigurationSections[1].Key);
            Assert.Equal("42", indexConfigurationSections[2].Key);
            Assert.Equal("1text", indexConfigurationSections[3].Key);
            Assert.Equal("bob", indexConfigurationSections[4].Key);
            Assert.Equal("hello", indexConfigurationSections[5].Key);
        }

Microsoft.Framework.Configuration.Xml

xml配置文件，在日常中用的也是比较多的，传统的配置文件就是xml的。[该处实现是支持内容加密的，具体不了解，略]

下面是xml文件的常规用法：

public void SupportAndIgnoreXMLDeclaration()
        {
            var xml =
                @"<?xml version='1.0' encoding='UTF-8'?>
                <settings>
                    <Data>
                        <DefaultConnection>
                            <ConnectionString>TestConnectionString</ConnectionString>
                            <Provider>SqlClient</Provider>
                        </DefaultConnection>
                        <Inventory>
                            <ConnectionString>AnotherTestConnectionString</ConnectionString>
                            <Provider>MySql</Provider>
                        </Inventory>
                    </Data>
                </settings>";
            var xmlConfigSrc = new XmlConfigurationSource(ArbitraryFilePath);

            xmlConfigSrc.Load(TestStreamHelpers.StringToStream(xml));

            Assert.Equal("TestConnectionString", xmlConfigSrc.Get("Data:DefaultConnection:ConnectionString"));
            Assert.Equal("SqlClient", xmlConfigSrc.Get("Data:DefaultConnection:Provider"));
            Assert.Equal("AnotherTestConnectionString", xmlConfigSrc.Get("Data:Inventory:ConnectionString"));
            Assert.Equal("MySql", xmlConfigSrc.Get("Data:Inventory:Provider"));
        }