c# - ASP.NET CORE 1.0, AppSettings from another assembly -

i have application splittet 2 projects: web application , class library. startup in web application:

var builder = new configurationbuilder()     .addjsonfile("appsettings.json") 

i wanna have appsettings.json in class library , being loaded there. possible? how can that?

the best solution have found requires creating new ifileprovider , ifileinfo, , embedding json settings files in assembly.

the solution reuses existing addjsonfile logic. way need tell configuration system how , locate json file, not how parse it.

the solution compatible .net core 1.0.

usage:

public class startup {     private readonly appsettings _appsettings;      public startup(ihostingenvironment env)     {         assembly assembly = typeof(yourclass).gettypeinfo().assembly;          new configurationbuilder()             .addembeddedjsonfile(assembly, "appsettings.json")             .addembeddedjsonfile(assembly, $"appsettings.{env.environmentname.tolower()}.json")             .build();     }      ... } 

embed files updating project.json class library:

... "buildoptions": {   "embed": [     "appsettings.json",     "appsettings.development.json",     "appsettings.production.json"   ] } ... 

iembeddedfileinfo implementation:

public class embeddedfileinfo : ifileinfo {     private readonly stream _filestream;      public embeddedfileinfo(string name, stream filestream)     {         if (name == null) throw new argumentnullexception(nameof(name));         if (filestream == null) throw new argumentnullexception(nameof(filestream));          _filestream = filestream;          exists = true;         isdirectory = false;         length = filestream.length;         name = name;         physicalpath = name;         lastmodified = datetimeoffset.now;     }      public stream createreadstream()     {         return _filestream;     }      public bool exists { get; }     public bool isdirectory { get; }     public long length { get; }     public string name { get; }     public string physicalpath { get; }     public datetimeoffset lastmodified { get; } } 

ifileinfo implementation:

public class embeddedfileprovider : ifileprovider {     private readonly assembly _assembly;      public embeddedfileprovider(assembly assembly)     {         if (assembly == null) throw new argumentnullexception(nameof(assembly));          _assembly = assembly;     }      public ifileinfo getfileinfo(string subpath)     {         string fullfilename = $"{_assembly.getname().name}.{subpath}";          bool isfileembedded = _assembly.getmanifestresourcenames().contains(fullfilename);          return isfileembedded             ? new embeddedfileinfo(subpath, _assembly.getmanifestresourcestream(fullfilename))             : (ifileinfo) new notfoundfileinfo(subpath);     }      public idirectorycontents getdirectorycontents(string subpath)     {         throw new notimplementedexception();     }      public ichangetoken watch(string filter)     {         throw new notimplementedexception();     } } 

create easy use addembeddedjsonfile extension method.

public static class configurationbuilderextensions {     public static iconfigurationbuilder addembeddedjsonfile(this iconfigurationbuilder configurationbuilder,         assembly assembly, string name, bool optional = false)     {         // reload on change not supported, pass in false         return configurationbuilder.addjsonfile(new embeddedfileprovider(assembly), name, optional, false);     } }