Azure Function, EF Core, Can't load ComponentModel.Annotations 4.2.0.0
I would suggest running this function below once you start your Azure Function. It will redirect any assembly to an existing version.
public class FunctionsAssemblyResolver
{
public static void RedirectAssembly()
{
var list = AppDomain.CurrentDomain.GetAssemblies().OrderByDescending(a => a.FullName).Select(a => a.FullName).ToList();
AppDomain.CurrentDomain.AssemblyResolve += CurrentDomain_AssemblyResolve;
}
private static Assembly CurrentDomain_AssemblyResolve(object sender, ResolveEventArgs args)
{
var requestedAssembly = new AssemblyName(args.Name);
Assembly assembly = null;
AppDomain.CurrentDomain.AssemblyResolve -= CurrentDomain_AssemblyResolve;
try
{
assembly = Assembly.Load(requestedAssembly.Name);
}
catch (Exception ex)
{
}
AppDomain.CurrentDomain.AssemblyResolve += CurrentDomain_AssemblyResolve;
return assembly;
}
}
I followed the instructions here:
https://codopia.wordpress.com/2017/07/21/how-to-fix-the-assembly-binding-redirect-problem-in-azure-functions/
And added the following redirect:
"BindingRedirects": "[ { "ShortName": "System.ComponentModel.Annotations", "RedirectToVersion": "4.2.1.0", "PublicKeyToken": "b03f5f7f11d50a3a" } ]"
NOTE: Its not v 4.5.0.0 ... Its actually 4.2.1.0.
The accepted response will cause a CPU leak due to the +=
if it is misused, and will grind your function app to a halt. If you are using IoC, it is better to use a singleton. Here:
public class FunctionsAssemblyResolver
{
static FunctionsAssemblyResolver()
{
AppDomain.CurrentDomain.AssemblyResolve += CurrentDomain_AssemblyResolve;
}
// At least one static member needs to be invoked in order to execute the static constructor,
// but it will only run the constructor once.
public static void StaticInstance() { }
private static Assembly CurrentDomain_AssemblyResolve(object sender, ResolveEventArgs args)
{
var requestedAssembly = new AssemblyName(args.Name);
try
{
// Feel free to resolve any other assemblies, but this will take care of Annotations
return requestedAssembly.Name == "System.ComponentModel.Annotations"
? Assembly.Load(requestedAssembly.Name)
: null;
}
catch
{
// do nothing
}
return null;
}
}
To use, just call FunctionsAssemblyResolver.StaticInstance()
prior to any IoC resolves. This can also be used for any non-IoC approach as well.