/Accelerator/Configuration/Settings.cs

using System;

using System.Collections.Generic;

using System.Diagnostics;

using System.IO;

using System.Linq;

using System.Xml.Linq;

using Microsoft.WindowsAzure.Accelerator.Configuration.Definition;

using Microsoft.WindowsAzure.Accelerator.Diagnostics;

using Environment = System.Environment;



namespace Microsoft.WindowsAzure.Accelerator.Configuration

{

    /// <summary>

    /// Manages settings from the Azure service definition (.csdef), service configuration (.cscfg),

    /// and service accelerator configuration (.accfg) files. (i|rdm)

    /// </summary>

    public class Settings

    {

        private const String _DefaultServiceConfigurationFile = "ServiceConfiguration.cscfg";

        private const String _DefaultServiceDefinitionFile = "ServiceDefinition.csdef";

        private const String _DefaultServiceAcceleratorFile = "ServiceAccelerator.accfg"; 

        private readonly XNamespace _cns = "http://schemas.microsoft.com/ServiceHosting/2008/10/ServiceConfiguration";

        private readonly XNamespace _dns = "http://schemas.microsoft.com/ServiceHosting/2008/10/ServiceDefinition";

        private readonly XNamespace _ans = "http://schemas.microsoft.com/ServiceHosting/2008/10/ServiceAcceleratorConfiguration";

        

        private ServiceBusConnection _serviceBusConnection;

        private CloudStorageAccount _cloudStorageAccount;

        private Path _serviceDefinitionFile;

        private Path _serviceConfigurationFile;

        private Path _serviceAcceleratorFile;

        private XElement _xServiceDefinition;

        private XElement _xServiceConfiguration;

        private XElement _xServiceAccelerator;

        private Dictionary<String, String> _configSettings;

        private ServiceDefinition _serviceDefinition;

        private ServiceConfiguration _serviceConfiguration;

        private ServiceAccelerator _serviceAccelerator;



        /// <summary>

        /// Initializes a new instance of the <see cref="Settings"/> class.

        /// </summary>

        public Settings() : this(_DefaultServiceDefinitionFile, _DefaultServiceConfigurationFile, _DefaultServiceAcceleratorFile) { }



        /// <summary>

        /// Initializes a new instance of the <see cref="Settings"/> class.

        /// </summary>

        /// <param name="serviceDefinitionFile">The service definition file.</param>

        /// <param name="serviceConfigurationFile">The service configuration file.</param>

        /// <param name="serviceAcceleratorFile">The service accelerator configuration file.</param>

        public Settings(Path serviceDefinitionFile, Path serviceConfigurationFile, Path serviceAcceleratorFile)

        {

            ServiceDefinitionFile = serviceDefinitionFile;

            ServiceConfigurationFile = serviceConfigurationFile;

            ServiceAcceleratorFile = serviceAcceleratorFile;

        }



        /// <summary>

        /// Gets a value indicating whether this instance is hostable web core.

        /// </summary>

        public Boolean IsHostableWebCore

        {

            get { return false; } //XServiceDefinition.Descendants("Site").FirstOrDefault() == null; }

        }



        /// <summary>

        /// Gets the diagnostics service bus connection.

        /// </summary>

        public ServiceBusConnection ServiceBusConnection

        {

            get { return _serviceBusConnection ?? ( _serviceBusConnection = ServiceBusConnection.Parse(GetConfigurationSetting("DiagnosticsServiceBus"))); }

        }



        /// <summary>

        /// Gets the default cloud drive URI.

        /// </summary>

        public String DefaultCloudDriveUri

        {

            get { return GetConfigurationSetting("AcceleratorDrivePageBlobUri") ?? DefaultSettings.CloudDriveUri;  }

        }



        /// <summary>

        /// Gets the default local site path.

        /// </summary>

        /// <remarks>

        /// Matained for HWC backwards compatiblity only. Is not useful for a SDK 1.3 sites based configuration,

        /// which includes a native physicalDirectory attribute.

        /// </remarks>

        public String DefaultLocalSitePath

        {

            get { return GetConfigurationSetting("LocalSitePath"); }

        }



        /// <summary>

        /// Gets the name of the application.

        /// </summary>

        public String ApplicationName

        {

            get { return ServiceConfiguration.serviceName; }

        }



        /// <summary>

        /// Gets the cloud storage account.

        /// </summary>

        public CloudStorageAccount CloudStorageAccount

        {

            get { return _cloudStorageAccount ?? ( _cloudStorageAccount = CloudStorageAccount.Parse(GetConfigurationSetting("AcceleratorConnectionString"))); }

        }

        

        /// <summary>

        /// Gets the service definition class information from the .csdef file.

        /// </summary>

        public ServiceDefinition ServiceDefinition

        {

            get { return _serviceDefinition ?? (_serviceDefinition = ServiceDefinition.LoadFromFile(ServiceDefinitionFile)); }

        }



        /// <summary>

        /// Gets the service configuration class from the cscfg file.

        /// </summary>

        public ServiceConfiguration ServiceConfiguration

        {

            get { return _serviceConfiguration ?? (_serviceConfiguration = ServiceConfiguration.LoadFromFile(ServiceConfigurationFile)); }

        }



        /// <summary>

        /// Gets the service accelerator configuration class from the accfg file.

        /// </summary>

        public ServiceAccelerator ServiceAccelerator

        {

            get { return _serviceAccelerator ?? (_serviceAccelerator = ServiceAccelerator.LoadFromFile(ServiceAcceleratorFile)); }

        }



        #region | XML



        /// <summary>

        /// Gets all 'Site' service definition elements defined in all roles.

        /// </summary>

        public List<XElement> XSites

        {

            get { return XServiceDefinition.Descendants(_dns + "Site").ToList(); }

        }



        /// <summary>

        /// Gets the service configuration setting elements.

        /// </summary>

        public Dictionary<String, String> ConfigurationSettings

        {

            get { return _configSettings ?? (_configSettings = GetRoleSettings(String.Empty)); }

            // XServiceConfiguration.Descendants(_cns + "Setting").ToDictionary(e => (String)e.Attribute("name"), e => (String)e.Attribute("value"))); }

        }



        /// <summary>

        /// Gets the service definition XML from the csdef file.

        /// </summary>

        public XElement XServiceDefinition

        {

            get { return _xServiceDefinition ?? (_xServiceDefinition = XDocument.Load(ServiceDefinitionFile).Element(_dns + "ServiceDefinition")); }

        }



        /// <summary>

        /// Gets the service configuration XML from the cscfg file.

        /// </summary>

        public XElement XServiceConfiguration

        {

            get { return _xServiceConfiguration ?? (_xServiceConfiguration = XDocument.Load(ServiceConfigurationFile).Element(_cns + "ServiceConfiguration")); }

        }



        /// <summary>

        /// Gets the service configuration XML from the cscfg file.

        /// </summary>

        public XElement XServiceAccelerator

        {

            get { return _xServiceAccelerator ?? (_xServiceAccelerator = XDocument.Load(ServiceAcceleratorFile).Element(_ans + "ServiceAccelerator")); }

        }



        #endregion

        #region | FILE RESOURCES



        /// <summary>

        /// Gets or sets the service definition (.csdef) file.

        /// </summary>

        public Path ServiceDefinitionFile

        {

            get { return _serviceDefinitionFile ?? (_serviceDefinitionFile = LocateConfigurationFile(_DefaultServiceDefinitionFile)); }

            set 

            { 

                if (!String.IsNullOrEmpty(value) && File.Exists(value))

                {

                    _serviceDefinitionFile = value;

                    _serviceDefinition = null;

                    _xServiceDefinition = null;

                }

            }

        }



        /// <summary>

        /// Gets or sets the service configuration (.cscfg) file.

        /// </summary>

        public Path ServiceConfigurationFile

        {

            get { return _serviceConfigurationFile ?? (_serviceConfigurationFile = LocateConfigurationFile(_DefaultServiceConfigurationFile)); }

            set 

            { 

                if (!String.IsNullOrEmpty(value) && File.Exists(value))

                {

                    _serviceConfigurationFile = value;

                    _serviceConfiguration = null;

                    _serviceConfigurationFile = null;

                }

            }

        }

        

        /// <summary>

        /// Gets or sets the service accelerator configuration (.accfg) file.

        /// </summary>

        public Path ServiceAcceleratorFile

        {

            get { return _serviceAcceleratorFile?? (_serviceAcceleratorFile= LocateConfigurationFile(_DefaultServiceAcceleratorFile)); }

            set

            {

                if (!String.IsNullOrEmpty(value) && File.Exists(value))

                {

                    _serviceAcceleratorFile= value;

                    _xServiceAccelerator = null;

                }

            }

        }



        /// <summary>

        /// Locates a configuration file using a known filename. This method will attempt to locate the file

        /// in the following four locations:

        ///   1. current directory

        ///   2. parent of current directory

        ///   3. binary directory

        ///   4. parent of binary directory

        /// </summary>

        /// <param name="filename">The file name.</param>

        private static Path LocateConfigurationFile(String filename)

        {

            Path path;

            if (!File.Exists(path = Path.Combine(".", filename).GetFullPath()))

                if (!File.Exists(path = path.Protect(p => p.GetParentFolder().Combine(filename))))

                    if (!File.Exists(path = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, filename)))

                        if (!File.Exists(path = path.Protect(p => p.GetParentFolder().Combine(filename))))

                            path = null;

            return path;

        }



        #endregion



        /// <summary>

        /// Gets the configuration setting.

        /// </summary>

        /// <param name="settingName">Name of the setting.</param>

        /// <returns></returns>

        public String GetConfigurationSetting(String settingName)

        {

            return GetRoleConfigurationSetting(settingName, String.Empty);

        }



        /// <summary>

        /// Gets the configuration setting.

        /// </summary>

        /// <param name="settingName">Name of the setting.</param>

        /// <param name="roleName">Name of the role.</param>

        /// <returns></returns>

        public String GetRoleConfigurationSetting(String settingName, String roleName)

        {

            return GetRoleSettings(roleName).OnValid(rs => rs.ContainsKey(settingName) ? rs[settingName] : null);

        }



        /// <summary>

        /// Gets the configuration setting elements for the specified role.

        /// </summary>

        /// <param name="roleName">Name of the role.</param>

        /// <returns>List of setting elements.</returns>

        public Dictionary<String,String> GetRoleSettings(String roleName)

        {

            XElement scope = (String.IsNullOrEmpty(roleName))

                                 ? XServiceConfiguration

                                 : //i|String query = String.Format("serviceAccelerator/application[@name=\"{0}\"]" 

                             (from r in XServiceConfiguration.Elements()

                              where r.GetAttribute("value") == roleName

                              select r).FirstOrDefault();



            return scope.Descendants(_cns + "Setting").ToDictionary(e => (String)e.Attribute("name"), e => (String)e.Attribute("value")); 

        }



        /// <summary>

        /// Pushes the values of each of the service configuration settings into environment variables by the same name.  Used to

        /// single-source configuration information, while leveraging batch files for deployment.

        /// </summary>

        public void SetConfigEnvironment()

        {

            Trace.TraceInformation("Setting Environment Variables");

            foreach (var setting in ConfigurationSettings)

            {

                try

                {

                    String key = setting.Key;

                    String value = setting.Value;

                    Environment.SetEnvironmentVariable(key, value);

                    Trace.TraceInformation("\t{0:20} : {1}", key, value);

                    if (!String.IsNullOrEmpty(value) && key.ToLower().Contains("connectionstring"))

                    {

                        foreach (var kvp in setting.Value.SplitToDictionary<String, String>(new[] { ';' }, new[] { '=' }).Where(d => !String.IsNullOrEmpty(d.Value)))

                        {

                            //b| this needs to take into account role and setting name in a compound form.

                            Environment.SetEnvironmentVariable(String.Format("{0}_{1}", key, kvp.Key), kvp.Value);

                            Environment.SetEnvironmentVariable(kvp.Key, kvp.Value);

                            Trace.TraceInformation("\t{0:20} : {1}", kvp.Key, kvp.Value);

                        }

                    }

                }

                catch (Exception ex)

                {

                   Trace.TraceError(ex.ToString());

                }

            }

        }

    }

}