Struct HttpClient 

pub struct HttpClient { /* private fields */ }

HTTP client with tower middleware stack

This client provides a clean interface over a tower service stack that includes:

• Timeout handling
• Automatic retries with exponential backoff
• User-Agent header injection
• Concurrency limiting (optional)

Use HttpClientBuilder to construct instances with custom configuration.

Thread Safety

HttpClient is Clone + Send + Sync. Cloning is cheap (internal channel clone). The client uses tower::buffer::Buffer internally, which allows true concurrent access without any mutex serialization. Callers do NOT need to wrap HttpClient in Mutex or Arc<Mutex<_>>.

Example

// Just store the client directly - no Mutex needed!
struct MyService {
    http: HttpClient,
}

impl MyService {
    async fn fetch(&self) -> Result<Data, HttpError> {
        // reqwest-like API: response has body-reading methods
        self.http.get("https://example.com/api").await?.json().await
    }
}

Implementations

impl HttpClient

pub fn new() -> Result<Self, HttpError>

Create a new HTTP client with default configuration

Errors

Returns an error if TLS initialization fails

pub fn builder() -> HttpClientBuilder

Create a builder for configuring the HTTP client

pub fn get(&self, url: &str) -> RequestBuilder

Create a GET request builder

Returns a RequestBuilder that can be configured with headers before sending with .send().await.

URL Requirements

The URL must be an absolute URI with scheme and authority (host). Relative URLs like /path or example.com/path are rejected with HttpError::InvalidUri.

Valid examples:

• https://api.example.com/users
• http://localhost:8080/health (requires TransportSecurity::AllowInsecureHttp)

URL Construction

Query parameters must be encoded into the URL externally (e.g. via url::Url):

use url::Url;

let mut url = Url::parse("https://api.example.com/search")?;
url.query_pairs_mut().append_pair("q", "rust").append_pair("page", "1");

let resp = client
    .get(url.as_str())
    .header("authorization", "Bearer token")
    .send()
    .await?;

Example

// Simple GET
let resp = client.get("https://api.example.com/data").send().await?;

pub fn post(&self, url: &str) -> RequestBuilder

Create a POST request builder

Returns a RequestBuilder that can be configured with headers, body (JSON, form, bytes), etc. before sending with .send().await.

Example

// POST with JSON body
let resp = client
    .post("https://api.example.com/users")
    .json(&NewUser { name: "Alice" })?
    .send()
    .await?;

// POST with form body
let resp = client
    .post("https://auth.example.com/token")
    .form(&[("grant_type", "client_credentials")])?
    .send()
    .await?;

pub fn put(&self, url: &str) -> RequestBuilder

Create a PUT request builder

Returns a RequestBuilder that can be configured with headers, body (JSON, form, bytes), etc. before sending with .send().await.

Example

let resp = client
    .put("https://api.example.com/resource/1")
    .json(&UpdateData { value: 42 })?
    .send()
    .await?;

pub fn patch(&self, url: &str) -> RequestBuilder

Create a PATCH request builder

Returns a RequestBuilder that can be configured with headers, body (JSON, form, bytes), etc. before sending with .send().await.

Example

let resp = client
    .patch("https://api.example.com/resource/1")
    .json(&PatchData { field: "new_value" })?
    .send()
    .await?;

pub fn delete(&self, url: &str) -> RequestBuilder

Create a DELETE request builder

Returns a RequestBuilder that can be configured with headers before sending with .send().await.

Example

let resp = client
    .delete("https://api.example.com/resource/42")
    .header("authorization", "Bearer token")
    .send()
    .await?;

Trait Implementations

impl Clone for HttpClient

fn clone(&self) -> HttpClient

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.