EnvironmentSettings.cs

using System;
using System.Threading.Tasks;
using Waher.Content;
using Waher.Content.Xml;
 
namespace Waher.Runtime.Settings
{
    public static class EnvironmentSettings
    {
        #region String-valued settings
 
        public static string Get(string EnvironmentVariable, string Key, string DefaultValue)
        {
            return GetAsync(EnvironmentVariable, Key, DefaultValue).Result;
        }
 
        public static Task<string> GetAsync(string EnvironmentVariable, string Key, string DefaultValue)
        {
            string s = Environment.GetEnvironmentVariable(EnvironmentVariable);
            if (s is null)
                return RuntimeSettings.GetAsync(Key, DefaultValue);
            else
                return Task.FromResult(s);
        }
 
        #endregion
 
        #region Int64-valued settings
 
        public static long Get(string EnvironmentVariable, string Key, long DefaultValue)
        {
            return GetAsync(EnvironmentVariable, Key, DefaultValue).Result;
        }
 
        public static Task<long> GetAsync(string EnvironmentVariable, string Key, long DefaultValue)
        {
            string s = Environment.GetEnvironmentVariable(EnvironmentVariable);
            if (s is null || !long.TryParse(s, out long Result))
                return RuntimeSettings.GetAsync(Key, DefaultValue);
            else
                return Task.FromResult(Result);
        }
 
        #endregion
 
        #region Boolean-valued settings
 
        public static bool Get(string EnvironmentVariable, string Key, bool DefaultValue)
        {
            return GetAsync(EnvironmentVariable, Key, DefaultValue).Result;
        }
 
        public static Task<bool> GetAsync(string EnvironmentVariable, string Key, bool DefaultValue)
        {
            string s = Environment.GetEnvironmentVariable(EnvironmentVariable);
            if (s is null || !CommonTypes.TryParse(s, out bool Result))
                return RuntimeSettings.GetAsync(Key, DefaultValue);
            else
                return Task.FromResult(Result);
        }
 
        #endregion
 
        #region DateTime-valued settings
 
        public static DateTime Get(string EnvironmentVariable, string Key, DateTime DefaultValue)
        {
            return GetAsync(EnvironmentVariable, Key, DefaultValue).Result;
        }
 
        public static Task<DateTime> GetAsync(string EnvironmentVariable, string Key, DateTime DefaultValue)
        {
            string s = Environment.GetEnvironmentVariable(EnvironmentVariable);
            if (s is null)
                return RuntimeSettings.GetAsync(Key, DefaultValue);
            else if (CommonTypes.TryParseRfc822(s, out DateTimeOffset Result))
                return Task.FromResult(Result.LocalDateTime);
            else if (XML.TryParse(s, out DateTime Result2))
                return Task.FromResult(Result2);
            else if (DateTime.TryParse(s, out Result2))
                return Task.FromResult(Result2);
            else
                return RuntimeSettings.GetAsync(Key, DefaultValue);
        }
 
        #endregion
 
        #region TimeSpan-valued settings
 
        public static TimeSpan Get(string EnvironmentVariable, string Key, TimeSpan DefaultValue)
        {
            return GetAsync(EnvironmentVariable, Key, DefaultValue).Result;
        }
 
        public static Task<TimeSpan> GetAsync(string EnvironmentVariable, string Key, TimeSpan DefaultValue)
        {
            string s = Environment.GetEnvironmentVariable(EnvironmentVariable);
            if (s is null || !TimeSpan.TryParse(s, out TimeSpan Result))
                return RuntimeSettings.GetAsync(Key, DefaultValue);
            else
                return Task.FromResult(Result);
        }
 
        #endregion
 
        #region Double-valued settings
 
        public static double Get(string EnvironmentVariable, string Key, double DefaultValue)
        {
            return GetAsync(EnvironmentVariable, Key, DefaultValue).Result;
        }
 
        public static Task<double> GetAsync(string EnvironmentVariable, string Key, double DefaultValue)
        {
            string s = Environment.GetEnvironmentVariable(EnvironmentVariable);
            if (s is null || !CommonTypes.TryParse(s, out double Result))
                return RuntimeSettings.GetAsync(Key, DefaultValue);
            else
                return Task.FromResult(Result);
        }
 
        #endregion
 
        #region Enum-valued settings
 
        public static Enum Get(string EnvironmentVariable, string Key, Enum DefaultValue)
        {
            return GetAsync(EnvironmentVariable, Key, DefaultValue).Result;
        }
 
        public static Task<Enum> GetAsync(string EnvironmentVariable, string Key, Enum DefaultValue)
        {
            string s = Environment.GetEnvironmentVariable(EnvironmentVariable);
            if (s is null)
                return RuntimeSettings.GetAsync(Key, DefaultValue);
 
            Type T = DefaultValue.GetType();
            string[] Names = Enum.GetNames(T);
            if (Array.IndexOf(Names, s) < 0)
                return RuntimeSettings.GetAsync(Key, DefaultValue);
 
            return Task.FromResult((Enum)Enum.Parse(T, s));
        }
 
        #endregion
    }
}