rust-client

A fast, opinionated command line HTTP client.

Fundamentally, rust-client is a thin wrapper around Rust's fantastic reqwest library. Unlike curl, however, it is designed more as a debugging tool. Headers are displayed above the response body, the command line interface is more intuitive than remembering flags, and default en-/decoding behavior.

Performance

The following is a totally unscientific benchmark using /usr/bin/time to finely measure memory usage and timing for rust-client, curl, and Python http; on my very old development box:

> /usr/bin/time -l rc get localhost:8000
GET http://localhost:8000/
HTTP/1.1 200 OK
content-length: 9
date: Tue, 10 Jul 2018 14:21:55 GMT
---
It works!
        0.01 real         0.00 user         0.00 sys
   7290880  maximum resident set size
         0  average shared memory size
         0  average unshared data size
         0  average unshared stack size
      1841  page reclaims
         0  page faults
         0  swaps
         0  block input operations
         0  block output operations
        10  messages sent
        10  messages received
         0  signals received
         4  voluntary context switches
        85  involuntary context switches

> /usr/bin/time -l curl localhost:8000
It works!        0.02 real         0.00 user         0.00 sys
   4956160  maximum resident set size
         0  average shared memory size
         0  average unshared data size
         0  average unshared stack size
      1259  page reclaims
         0  page faults
         0  swaps
         0  block input operations
         0  block output operations
        10  messages sent
        10  messages received
         0  signals received
         7  voluntary context switches
        28  involuntary context switches

> /usr/bin/time -l http localhost:8000
HTTP/1.1 200 OK
content-length: 9
date: Tue, 10 Jul 2018 14:24:20 GMT

It works!

        0.62 real         0.41 user         0.18 sys
  26628096  maximum resident set size
         0  average shared memory size
         0  average unshared data size
         0  average unshared stack size
     26378  page reclaims
         0  page faults
         0  swaps
         0  block input operations
         0  block output operations
        10  messages sent
        10  messages received
        25  signals received
        77  voluntary context switches
       524  involuntary context switches

Note, the measurement of http is after warming up the Python runtime using multiple runs of http. The following is the initial result:

HTTP/1.1 200 OK
content-length: 9
date: Tue, 10 Jul 2018 14:23:53 GMT

It works!

        3.06 real         0.37 user         0.21 sys
  26618280  maximum resident set size
         0  average shared memory size
         0  average unshared data size
         0  average unshared stack size
     25678  page reclaims
       684  page faults
         0  swaps
       133  block input operations
         0  block output operations
        11  messages sent
        11  messages received
        25  signals received
       669  voluntary context switches
       675  involuntary context switches

While rust-client and curl perform similarly, curl does not print the same level of information that rust-client does.

The test server is the example server from hyper's documentation.

TODO

• Colorize output
• HTML pretty printing
• encode body content in a specific format (JSON, YAML, etc)
• decode response based on Content-Type