Send SMS

Single

{
  "messages": [
    {
      "sender": "everymessage",
      "content": "Your appointment is confirmed for 10:30 tomorrow.",
      "recipient": [
        {
          "number": "447700900123"
        }
      ],
      "reference": "booking-1042",
      "registeredDelivery": true
    }
  ]
}

C#

// Send an SMS with the everymessage v1 API (.NET 8 or later)
using System.Net.Http.Headers;
using System.Net.Http.Json;
using System.Text;
using System.Text.Json;
using System.Text.Json.Serialization;

var apiKey = Environment.GetEnvironmentVariable("EM_API_KEY")!;
var secretKey = Environment.GetEnvironmentVariable("EM_SECRET_KEY")!;

using var http = new HttpClient { BaseAddress = new Uri("https://api.everymessage.com/") };
http.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue(
    "Basic", Convert.ToBase64String(Encoding.UTF8.GetBytes($"{apiKey}:{secretKey}")));

var json = new JsonSerializerOptions(JsonSerializerDefaults.Web)
{
    DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull
};

var request = new SubmitRequest(
[
    new Message(
        Sender: "everymessage",
        Content: "Your appointment is confirmed for 10:30 tomorrow.",
        Recipient: [new Recipient("447700900123")],
        Reference: "booking-1042",
        RegisteredDelivery: true)
]);

using var response = await http.PostAsJsonAsync("v1/submit", request, json);
response.EnsureSuccessStatusCode();

var result = await response.Content.ReadFromJsonAsync<ApiEnvelope<SubmitBody>>(json)
             ?? throw new InvalidOperationException("Empty response from everymessage");

// The API returns HTTP 200 even on errors: check responseStatusReason.
if (result.ResponseStatusReason is not null)
    throw new InvalidOperationException($"Submit failed: {result.ResponseStatusReason}");

foreach (var s in result.Body!.Submissions)
    Console.WriteLine($"{s.Recipient}: {s.Status} (id {s.Id}, {s.Segments ?? 0} part(s))");

Console.WriteLine($"Charged {result.Body.Charged}, balance {result.Body.Balance}");

record SubmitRequest(IReadOnlyList<Message> Messages);
record Message(string Sender, string Content, IReadOnlyList<Recipient> Recipient,
    string? Reference = null, bool RegisteredDelivery = false);
record Recipient(string Number);

record ApiEnvelope<T>(int ResponseStatusCode, string? ResponseStatusReason, int ProcessingTime, T? Body);
// Fields with no value are left out of the response, so keep them nullable.
record SubmitBody(decimal? Balance, decimal? Charged, IReadOnlyList<Submission> Submissions);
record Submission(long Id, string Status, string Recipient, string? Sender,
    int? Segments, decimal? Charged);