Program.cs

using System.Net.Http.Headers;
using BooleanApi.Services;
using BooleanApi.Validation;
using Microsoft.Extensions.Options;


var builder = WebApplication.CreateBuilder(args);

builder.Services.AddControllers()
 .AddJsonOptions(o =>
 {
 // Enables polymorphic JSON using attributes in the AST models
 o.JsonSerializerOptions.PropertyNamingPolicy = System.Text.Json.JsonNamingPolicy.CamelCase;
 });

builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();

builder.Services.AddSingleton<BooleanApi.Validation.FieldCardinality>();
builder.Services.AddSingleton<BooleanApi.Validation.ImpossibleQueryDetector>();

builder.Services.Configure<OpenSearchOptions>(builder.Configuration.GetSection("OpenSearch"));

// Field allow-list registry
builder.Services.AddSingleton<FieldRegistry>();

builder.Services.AddSingleton<ContainsFieldRegistry>();

// Query translation (Boolean AST -> OpenSearch DSL)
builder.Services.AddSingleton<QueryTranslator>();

// OpenSearch client service
builder.Services.AddHttpClient<OpenSearchService>((sp, client) =>
{
 var opts = sp.GetRequiredService<IOptions<OpenSearchOptions>>().Value;

 client.BaseAddress = new Uri(opts.BaseUrl.TrimEnd('/') + "/");
 client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));

 // Optional auth
 if (!string.IsNullOrWhiteSpace(opts.ApiKey))
 {
 client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("ApiKey", opts.ApiKey);
 }
 else if (!string.IsNullOrWhiteSpace(opts.Username))
 {
 var raw = $"{opts.Username}:{opts.Password}";
 var b64 = Convert.ToBase64String(System.Text.Encoding.UTF8.GetBytes(raw));
 client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic", b64);
 }
});

builder.Services.AddControllers()
 .AddJsonOptions(o =>
 {
 o.JsonSerializerOptions.PropertyNamingPolicy = System.Text.Json.JsonNamingPolicy.CamelCase;
 o.JsonSerializerOptions.Converters.Add(new BooleanApi.Models.JsonElementValueConverter());
 });

builder.Services.AddCors(options =>
{
 options.AddPolicy("AllowAll",
 builder =>
 {
 builder.AllowAnyOrigin()
 .AllowAnyMethod()
 .AllowAnyHeader();
 });
});

var app = builder.Build();

app.UseCors("AllowAll");

if (app.Environment.IsDevelopment())
{
 app.UseSwagger();
 app.UseSwaggerUI();
}

app.MapControllers();
/*
// This code can be commented out in production v
app.Use(async (context, next) => 
{
 // Check if it's the specific port or path to avoid noise
 if (context.Request.Method == "POST") 
 {
 context.Request.EnableBuffering();

 // LeaveOpen: true is critical so the stream isn't closed before the controller sees it
 using (var reader = new StreamReader(context.Request.Body, leaveOpen: true))
 {
 var rawBody = await reader.ReadToEndAsync();
 
 // --- SET BREAKPOINT HERE ---
 // Inspect 'rawBody' in VS Code Variables window
 
 context.Request.Body.Position = 0; // Rewind the stream for the next guy
 }
 }
 await next();
});
// This code can be commented out in production ^
*/
app.Run();