Record-and-replay testing middleware for reqwest http client.

Inspired by:

• Ruby-VCR
• Surf-VCR

Builds on top of:

• reqwest-middleware
• VCR-cassette

To record HTTP requests, initialize client like following

  use std::path::PathBuf;
  use reqwest::Client;
  use reqwest_middleware::{ClientBuilder, ClientWithMiddleware};
  use rvcr::{VCRMiddleware, VCRMode};

  let mut bundle = PathBuf::from(env!("CARGO_MANIFEST_DIR"));
  bundle.push("tests/resources/replay.vcr.json");

  let middleware: VCRMiddleware = VCRMiddleware::try_from(bundle.clone())
      .unwrap()
      .with_mode(VCRMode::Record);

  let vcr_client: ClientWithMiddleware = ClientBuilder::new(reqwest::Client::new())
      .with(middleware)
      .build();

Now ClientWithMiddleware instance will be recording requests to a file located in tests/resources/replay.vcr.json inside the project.

To use recorded VCR cassette files, replace .with_mode(VCRMode::Record) with .with_mode(VCRMode::Replay), or omit it, since replay is used by default.

When replaying, rVCR can skip requests already found when searching for subsequent requests (the default). To disable skipping requests, which is useful, for example, if requests are done in parallel and responses may come in random order, use .with_search(VCRReplaySearch::SearchAll).

Your requests and responses may contain sensitive information such as authentication details, user information etc. which you don't want to commit to your source control.

You can modify requests and responses before they are stored and restored using with_modify_request and with_modify_response.

You can change anything in the body, URI, headers etc. to hide any information you want. Here's an example which filters sensitive information in query parameters:

  let middleware = VCRMiddleware::try_from(bundle.clone())
      .unwrap()
      .with_mode(VCR::Record)
      .with_modify_request(|req| {
          let sensitive_query_params = ["access_token", "appsecret_proof"];

          // Replace sensitive data in query params
          let filtered_query_params = req.uri.clone().query_pairs().map(|(k, v)| {
              if sensitive_query_params.contains(&k.as_ref()) {
                  (k.clone(), Cow::from(k.to_uppercase()))
              } else {
                  (k, v)
              }
          });

          // Overwrite query params with filtered ones
          req.uri
              .query_pairs_mut()
              .clear()
              .extend_pairs(filtered_query_params)
              .finish();
      });

Sometimes VCR files can be too large and this harder to maintain in a version control system.

To save some space and turn on bzip2 compression for artifacts, use .compression(true) method of the builder.