Error when using a precompiled Azure Function with extra methods - azure

Question

I have created a very simple Precompiled function (copied code from tool generated):
public class Foo
{
public static async Task<HttpResponseMessage> Run(HttpRequestMessage req)
{
//log.Info($"C# HTTP trigger function processed a request. RequestUri={req.RequestUri}");
// parse query parameter
string name = req.GetQueryNameValuePairs()
.FirstOrDefault(q => string.Compare(q.Key, "name", true) == 0)
.Value;
// Get request body
dynamic data = await req.Content.ReadAsAsync<object>();
// Set name to query string or body data
name = name ?? data?.name;
return name == null
? req.CreateResponse(HttpStatusCode.BadRequest, "Please pass a name on the query string or in the request body")
: req.CreateResponse(HttpStatusCode.OK, "Hello " + name);
}
}
The dll this resides in is copied to the Function's folder and is linked up in function.json like this:
{
"scriptFile": "ExternalFunction.dll",
"entryPoint": "ExternalFunction.Foo.Run",
"disabled": false,
"bindings": [
{
"authLevel": "function",
"name": "req",
"type": "httpTrigger",
"direction": "in"
},
{
"name": "res",
"type": "http",
"direction": "out"
}
]
}
This all works fine.
What I then wanted to do was add a private method to be called from the Run method, so (baby steps) I added this to the Foo class:
private static string Test()
{
return "Hello";
}
This results in these errors in the CLI tools:
error AF007: A method matching the entry point name provided in
configuration ('ExternalFunction.Foo.Run') does not exist. Your
function must contain a single public method, a public method named
'Run', or a public method matching the name specified in the
'entryPoint' metadata property. Function compilation error error
AF007: A method matching the entry point name provided in
configuration ('ExternalFunction.Foo.Run') does not exist. Your
function must contain a single public method, a public method named
'Run', or a public method matching the name specified in the
'entryPoint' metadata property.
Which is a very odd message as surely adding the private static method should have no effect on Functions being able to find the public method specified in function.json?!
Any ideas?

Answer 1

This is indeed odd.
I'll work on a repro and open an issue to address the problem if this turns out to be a defect (I'll update the issue or the results of my investigation), but in the meantime, you should be able to create those methods in a different class (static or otherwise) and call that method on that class.