How to handle GZip/Deflate on HTTP Actions - azure-logic-apps

Question

I have an HTTP Action in Azure Logic Apps that calls a StackExchange API, fundamentally, it could be any API that returned GZip or Deflate content by default:
Because the response is neither Plain Text nor JSON the output from the HTTP Action is:
{
"$content-encoding": "gzip",
"$content-type": "application/json; charset=utf-8",
"$content": "H4sIAAAAAAAEAGWPzY7CMAyE38XnqsrPFtq+ClpFoXghEkm6iVtWQrw7Lt3mAEd/Hs+M7+AIfYb+cIeAN2MHcjOaKWNiKCqgSPa6zZ2SFRzt6YzZjJiMd2EiZF0tvjbpuoZe7rrdxuZIC9KNLo5D9B4DLUIl2gpsyDfOeLflvN8JM7kYPnbF6/+WA/ZNYcOAI+Hp5V/eCKv0heVGSwD0SnRcZXQm4ewyM+hBCbmvda3aWjVaS3h8V3Cx2fiYuMePvWZcSrKV8faPSyzF1jmhty64cGbnVjyeRIHcnG0BAAA="
}
If you went to the trouble of passing the $content field through #base64toString() you would end up with the Gzip binary representation of the JSON, and that is as far as I can take it.
Question: How can I either force the HTTP Action to behave like a HttpClient and Accept GZip data and emit the JSON from the Action, or more laboriously take the GZip Base64/Binary data and decompress it before acting further upon it?

Answer 1

I wasn't able to find a way to "solve" the problem directly, so I created an Azure Function that made the request to the URL with the appropriate HttpClientHandler passed into the HttpClient:
#r "Newtonsoft.Json"
using System;
using System.Net;
using Newtonsoft.Json;
public static async Task<object> Run(HttpRequestMessage req, TraceWriter log) {
string jsonContent = await req.Content.ReadAsStringAsync();
dynamic data = JsonConvert.DeserializeObject(jsonContent);
if (data.url == null) {
return req.CreateResponse(HttpStatusCode.BadRequest, new {
error = "Please pass a URL in the input object"
});
}
HttpClientHandler handler = new HttpClientHandler() {
AutomaticDecompression = DecompressionMethods.GZip | DecompressionMethods.Deflate
};
var client = new HttpClient(handler);
var result = await client.GetAsync((string)data.url);
var response = req.CreateResponse(HttpStatusCode.OK);
response.Content = result.Content;
return response;
}
By swapping the built-in HTTP Action from the original question, I was able to get this working:
And the configuration for the Azure Function is as follows: