refactor: digest_auth related tests (#372)

tests/digest_auth_util.rs

@@ -0,0 +1,91 @@
+/// Refs https://github.dev/maoertel/diqwest/blob/main/src/blocking.rs
+use anyhow::{anyhow, Result};
+use digest_auth::{AuthContext, AuthorizationHeader, HttpMethod};
+use hyper::{header::AUTHORIZATION, HeaderMap, StatusCode};
+use reqwest::blocking::{RequestBuilder, Response};
+use url::Position;
+
+pub fn send_with_digest_auth(
+    request_builder: RequestBuilder,
+    username: &str,
+    password: &str,
+) -> Result<Response> {
+    let first_response = try_clone_request_builder(&request_builder)?.send()?;
+    match first_response.status() {
+        StatusCode::UNAUTHORIZED => {
+            try_digest_auth(request_builder, first_response, username, password)
+        }
+        _ => Ok(first_response),
+    }
+}
+
+fn try_digest_auth(
+    request_builder: RequestBuilder,
+    first_response: Response,
+    username: &str,
+    password: &str,
+) -> Result<Response> {
+    if let Some(answer) = get_answer(
+        &request_builder,
+        first_response.headers(),
+        username,
+        password,
+    )? {
+        return Ok(request_builder
+            .header(AUTHORIZATION, answer.to_header_string())
+            .send()?);
+    };
+
+    Ok(first_response)
+}
+
+fn try_clone_request_builder(request_builder: &RequestBuilder) -> Result<RequestBuilder> {
+    request_builder
+        .try_clone()
+        .ok_or_else(|| anyhow!("Request body must not be a stream"))
+}
+
+fn get_answer(
+    request_builder: &RequestBuilder,
+    first_response: &HeaderMap,
+    username: &str,
+    password: &str,
+) -> Result<Option<AuthorizationHeader>> {
+    let answer = calculate_answer(request_builder, first_response, username, password);
+    match answer {
+        Ok(answer) => Ok(Some(answer)),
+        Err(error) => Err(error),
+    }
+}
+
+fn calculate_answer(
+    request_builder: &RequestBuilder,
+    headers: &HeaderMap,
+    username: &str,
+    password: &str,
+) -> Result<AuthorizationHeader> {
+    let request = try_clone_request_builder(request_builder)?.build()?;
+    let path = &request.url()[Position::AfterPort..];
+    let method = HttpMethod::from(request.method().as_str());
+    let body = request.body().and_then(|b| b.as_bytes());
+
+    parse_digest_auth_header(headers, path, method, body, username, password)
+}
+
+fn parse_digest_auth_header(
+    header: &HeaderMap,
+    path: &str,
+    method: HttpMethod,
+    body: Option<&[u8]>,
+    username: &str,
+    password: &str,
+) -> Result<AuthorizationHeader> {
+    let www_auth = header
+        .get("www-authenticate")
+        .ok_or_else(|| anyhow!("The header 'www-authenticate' is missing."))?
+        .to_str()?;
+    let context = AuthContext::new_with_method(username, password, path, body, method);
+    let mut prompt = digest_auth::parse(www_auth)?;
+
+    Ok(prompt.respond(&context)?)
+}