How do you include references to external assemblies in Azure Functions

Question

I tried the following:

using System;
using Newtonsoft.Json
using Newtonsoft.Linq

public static void Run(string myEventHubMessage, out string document, TraceWriter log)
{
    log.Verbose($"C# Event Hub trigger function processed a message: {myEventHubMessage}");
    dynamic jsonData = JObject.Parse(myEventHubMessage);
    document = jsonData;
}

I get the following when I hit the "Save" button in Azure portal:

2016-04-05T21:28:31 Welcome, you are now connected to log-streaming service. 2016-04-05T21:28:33.443 Script for function 'ProbeEventHubTrigger' changed. Reloading. 2016-04-05T21:28:33.443 Compiling function script. 2016-04-05T21:28:33.568 (2,22): error CS1002: ; expected 2016-04-05T21:28:33.568 (3,22): error CS1002: ; expected 2016-04-05T21:28:33.568 (2,7): error CS0246: The type or namespace name 'Newtonsoft' could not be found (are you missing a using directive or an assembly reference?) 2016-04-05T21:28:33.568 (3,7): error CS0246: The type or namespace name 'Newtonsoft' could not be found (are you missing a using directive or an assembly reference?) 2016-04-05T21:28:33.568 (8,24): error CS0103: The name 'JObject' does not exist in the current context 2016-04-05T21:28:33.568 Compilation failed.

I also tried the following:

#r "Newtonsoft.Json"
#r "Newtonsoft.Linq"
using System;

public static void Run(string myEventHubMessage, out string document, TraceWriter log)
{
    log.Verbose($"C# Event Hub trigger function processed a message: {myEventHubMessage}");
    dynamic jsonData = JObject.Parse(myEventHubMessage);
    document = jsonData;
}

In this case I get the following when I hit the "Save" button in the Azure portal:

2016-04-05T21:35:36 Welcome, you are now connected to log-streaming service. 2016-04-05T21:35:38.428 Script for function 'ProbeEventHubTrigger' changed. Reloading. 2016-04-05T21:35:38.428 Compiling function script. 2016-04-05T21:35:38.571 (2,1): error CS0006: Metadata file 'Newtonsoft.Linq' could not be found 2016-04-05T21:35:38.571 (8,24): error CS0103: The name 'JObject' does not exist in the current context

It's not obvious from the documentation how to reference these assemblies. I see in one example the syntax is "using Newtonsoft.Json", but this doesn't appear to work in the portal. Any suggestions?

Answer 1

Steve,

.NET Framework assemblies and a few "shared" assemblies may be added with the following syntax:

#r "AssemblyName"

So, for JSON.NET, you can use:

#r "Newtonsoft.Json"

Once the reference is added, then you can add your using statements as you would in a regular C# project/file:

using Newtonsoft.Json;

So, in summary, you need to add a reference to the assemblies you want to use, and import the namespaces exposed by that assembly so you can use its types. This is similar to what you'd do in Visual Studio, where you add the assembly reference and then add your using statements where you need them.

I hope this helps!