> ## Documentation Index > Fetch the complete documentation index at: https://docs-unity.molca.id/llms.txt > Use this file to discover all available pages before exploring further. # HttpClient and HttpRequestAsset > Async HTTP, ScriptableObject-defined endpoints, and integration with session code. **Files:** * `Packages/com.molca.core/Runtime/Networking/Http/HttpClient.cs` * `Packages/com.molca.core/Runtime/Networking/Http/HttpRequestAsset.cs` ## When to use * **`HttpRequestAsset`** (recommended) — for data-driven endpoints where URL, method, headers, and body templates live in a ScriptableObject. Best for stable API calls configured once in the Inspector. * **`HttpRequestBuilder`** (programmatic) — for dynamic endpoints or when URL/body must be built at runtime. Uses a fluent builder API. * Both route through the same `HttpClient` subsystem with queuing, concurrency control, and connection error events. ## HttpClient `RuntimeSubsystem` — async HTTP with request queuing, auth header management, and event hooks. > ⚠️ **The static `HttpClient.*` API is deprecated.** All static members (`SendAsync`, `Send`, `CreateRequest`, `BaseUrl`, events, etc.) are marked `[Obsolete]`. Use the **`IHttpClient` instance interface** instead: > > ```csharp theme={null} > var http = RuntimeManager.GetService(); > ``` > > Or inject via `[Inject] IHttpClient http;` ### IHttpClient (recommended) | Member | Signature | Description | | ----------------------- | ------------------------------------------------------------------------------------------------------------------------------------ | ------------------------------------------------------------ | | `BaseUrl` | `string BaseUrl { get; }` | Base URL from configured `HttpModule`, or empty | | `MaxConcurrentRequests` | `int MaxConcurrentRequests { get; }` | Max concurrent in-flight requests | | `ActiveRequestCount` | `int ActiveRequestCount { get; }` | Number of requests currently in flight | | `RequestHistory` | `IReadOnlyList RequestHistory { get; }` | Completed-request history | | `SendAsync` | `Awaitable SendAsync(HttpRequest request, CancellationToken ct = default)` | Send and await response with optional cancellation | | `Send` | `void Send(HttpRequest req, CancellationToken ct, Action onSuccess, Action onError, Action onProgress)` | Callback-style send with cancellation | | `CreateRequest` | `HttpRequestBuilder CreateRequest()` | Start a fluent builder chain | | `AddDefaultHeader` | `void AddDefaultHeader(string key, string value)` | Add header to all future requests | | `RemoveDefaultHeader` | `void RemoveDefaultHeader(string key)` | Remove a default header | | `ClearDefaultHeaders` | `void ClearDefaultHeaders()` | Clear all default headers | | `CancelAllRequests` | `void CancelAllRequests()` | Abort all active and queued requests | | `AddInterceptor` | `void AddInterceptor(IHttpRequestInterceptor interceptor)` | Register a request interceptor | | `RemoveInterceptor` | `void RemoveInterceptor(IHttpRequestInterceptor interceptor)` | Remove a previously registered interceptor | | `SetRetryPolicy` | `void SetRetryPolicy(HttpRetryPolicy policy)` | Override retry policy (null restores module default) | | `SetTransport` | `void SetTransport(IHttpTransport transport)` | Replace transport (null restores `UnityWebRequestTransport`) | | `ClearHistory` | `void ClearHistory()` | Clears the request history | **Events:** `RequestStarted`, `RequestCompleted`, `RequestFailed`, `ConnectionError` (instance `event Action`). ### Legacy static API (deprecated) The following static members on `HttpClient` still compile but are `[Obsolete]` — migrate to the `IHttpClient` instance pattern above. | Member | Migration | | ----------------------------------- | ----------------------------- | | `HttpClient.SendAsync(request)` | `http.SendAsync(request)` | | `HttpClient.Send(...)` | `http.Send(...)` | | `HttpClient.CreateRequest()` | `http.CreateRequest()` | | `HttpClient.AddDefaultHeader(k, v)` | `http.AddDefaultHeader(k, v)` | | `HttpClient.BaseUrl` | `http.BaseUrl` | | `HttpClient.OnRequestStarted` | `http.RequestStarted` | | `HttpClient.SetRetryPolicy(p)` | `http.SetRetryPolicy(p)` | ## HttpRequestAsset ScriptableObject describing URL, method, headers, and body templates. Create via **Molca → Networking → HTTP Request**. | Method | Signature | Description | | --------------- | --------------------------------------------------------------------------------------------- | ---------------------------------------------- | | `SendAsync` | `async Awaitable SendAsync()` | Send this asset's configured request | | `Send` | `void Send(Action onSuccess, Action onError, Action onProgress)` | Callback-style send | | `CreateBuilder` | `HttpRequestBuilder CreateBuilder()` | Clone into a builder for runtime modifications | | `Validate` | `bool Validate(out string[] errors)` | Check configuration before sending | ## Code **From a `HttpRequestAsset`** (recommended when the request is mostly data-driven): ```csharp theme={null} using Molca.Networking.Http; using UnityEngine; public class ProfileClient : MonoBehaviour { [SerializeField] private HttpRequestAsset fetchProfile; private async void Start() { await RuntimeManager.WaitForInitialization(); var response = await fetchProfile.SendAsync(); if (response.IsSuccess) Debug.Log(response.Text); } } ``` **Programmatic** requests using the fluent builder (preferred — uses `IHttpClient`): ```csharp theme={null} using Molca.Networking.Http; using Molca; using UnityEngine; public class DynamicApiClient : MonoBehaviour { [Inject] private IHttpClient _http; private async void Start() { await RuntimeManager.WaitForInitialization(); if (_http == null) return; var response = await _http.CreateRequest() .Method(HttpMethod.GET) .Url("/api/users/42") .Header("Accept", "application/json") .Timeout(10) .SendAsync(); if (response.IsSuccess) Debug.Log(response.Text); else Debug.LogError(response.ErrorMessage); } } ``` ## API Reference ### IHttpClient (instance API) See the [IHttpClient table](#IHttpClient-recommended) above. Resolve via: ```csharp theme={null} var http = RuntimeManager.GetService(); // Or inject: [Inject] private IHttpClient _http; ``` ### HttpRequestAsset | Method | Signature | Description | | --------------- | --------------------------------------------------------------------------------------------- | ---------------------------------------------- | | `SendAsync` | `async Awaitable SendAsync()` | Send this asset's configured request | | `Send` | `void Send(Action onSuccess, Action onError, Action onProgress)` | Callback-style send | | `CreateBuilder` | `HttpRequestBuilder CreateBuilder()` | Clone into a builder for runtime modifications | | `Validate` | `bool Validate(out string[] errors)` | Check configuration before sending | ### HttpRequestBuilder | Method | Signature | Description | | ----------- | ----------------------------------------------------- | ---------------------------------------- | | `Method` | `HttpRequestBuilder Method(HttpMethod method)` | Set HTTP method (GET, POST, PUT, DELETE) | | `Url` | `HttpRequestBuilder Url(string url)` | Set relative or absolute URL | | `FullUrl` | `HttpRequestBuilder FullUrl(string url)` | Set absolute URL, bypassing BaseUrl | | `Header` | `HttpRequestBuilder Header(string key, string value)` | Add a request header | | `Body` | `HttpRequestBuilder Body(string body)` | Set request body content | | `Timeout` | `HttpRequestBuilder Timeout(int seconds)` | Set request timeout | | `SendAsync` | `async Awaitable SendAsync()` | Build and send the request | ## Troubleshooting * **Request fails silently:** subscribe to `HttpClient.OnRequestFailed` or `OnConnectionError` for diagnostics. The request may have been queued but not started if `MaxConcurrentRequests` is exceeded. * **Auth header missing on requests:** call `HttpClient.AddDefaultHeader("Authorization", "Bearer " + token)` after login. Default headers are applied to all future requests automatically. * **Wrong base URL:** `BaseUrl` comes from `HttpModule` on [Global Settings](/setup/global-settings). If the module is missing, URLs must be absolute (set `useFullUrl = true` or use `FullUrl()` on the builder). * **Request validation fails:** `HttpRequestAsset.Validate(out errors)` will return `false` if the URL is empty or malformed. Check the `errors` array for specifics. ## Related * [DataManager](/core/data-manager) — for persistent data providers rather than one-off requests * [Scenario network config](/vr/scenario-network-config) — VR session HTTP endpoints * [Global Settings](/setup/global-settings) — `HttpModule` base URL and defaults * [Recipe: Integrate HTTP requests with data persistence](/recipes/integrate-http-data-persistence) — step-by-step guide to combining HttpClient and DataManager for API calls with local caching ## Unity Editor Http Request Asset Inspector