Azure Function code to send a Tweet to the V2 Twitter API using OAUTH1.0

run.csx

#r "Newtonsoft.Json"

using System.Text;
using System.Net;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Primitives;
using Newtonsoft.Json;
using OAuth;

public static async Task<IActionResult> Run(HttpRequest req, ILogger log)
{
    log.LogInformation("C# HTTP trigger function to send a Tweet.");

    string oauth_consumer_key = Environment.GetEnvironmentVariable("oauth_consumer_key");
    string oauth_consumer_secret = Environment.GetEnvironmentVariable("oauth_consumer_secret");
    string oauth_token = Environment.GetEnvironmentVariable("oauth_token");
    string oauth_token_secret = Environment.GetEnvironmentVariable("oauth_token_secret");

    string url = "https://api.twitter.com/2/tweets";

    string tweet = req.Query["tweet"];
    string requestBody = await new StreamReader(req.Body).ReadToEndAsync();
    dynamic data = JsonConvert.DeserializeObject(requestBody);
    tweet = tweet ?? data?.tweet;


    log.LogInformation($"Message:{tweet}");

    var oauth = new OAuthMessageHandler(oauth_consumer_key, oauth_consumer_secret, oauth_token, oauth_token_secret);

    var tweetData = new { text = tweet };
    var jsonData = JsonConvert.SerializeObject(tweetData);

    var createTweetRequest = new HttpRequestMessage(HttpMethod.Post, url)
    {
        Content = new StringContent(jsonData, Encoding.UTF8, "application/json")
    };

    using var httpClient = new HttpClient(oauth);

    var response = await httpClient.SendAsync(createTweetRequest);
    log.LogInformation("Tweet sent successfully!");
    return new OkObjectResult("Tweet sent successfully!");
}

Note that for this to work you also need a function.proj file upload that adds the reference to OAuth.net

    <Project Sdk="Microsoft.NET.Sdk">
    <PropertyGroup>
        <TargetFramework>netstandard2.0</TargetFramework>
      </PropertyGroup>

      <ItemGroup>
        <PackageReference Include="OAuth.net" Version="1.7.0" />
      </ItemGroup>
    </Project>