Istanbul Middleware for Connect/Express

istanbul-middleware is a Connect/Express middleware package designed to integrate Istanbul code coverage into Node.js applications, supporting both server-side and browser-side code coverage during functional tests. It allows developers to hook `require()` for server-side instrumentation, expose dynamic HTML coverage reports, reset coverage data, and download reports via special HTTP endpoints (e.g., `/coverage`). It also provides mechanisms to instrument JavaScript files delivered to the browser and aggregate client-side coverage data posted back to the server. The package's current stable version is 0.2.2, with the last update approximately 10 years ago (as of 2024). It was explicitly labeled as 'experimental' and suitable for 'narrow use-cases' like Express 3. Its key differentiator was providing a server-integrated solution for coverage, aggregating data from various sources. Due to its age and lack of updates, the project is considered abandoned, and newer alternatives for code coverage (like the `istanbuljs` ecosystem) should be preferred.