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. Each app was run 5 times on a warm cache, with the following being the averages:

> /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!
        0.03 real         0.01 user         0.01 sys
   9494528  maximum resident set size
         0  average shared memory size
         0  average unshared data size
         0  average unshared stack size
      2376  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
        95  involuntary context switches

> /usr/bin/time -l curl localhost:8000
It works!        0.03 real         0.01 user         0.00 sys
   5005312  maximum resident set size
         0  average shared memory size
         0  average unshared data size
         0  average unshared stack size
      1272  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
        47  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!

        0.80 real         0.45 user         0.26 sys
  26623181  maximum resident set size
         0  average shared memory size
         0  average unshared data size
         0  average unshared stack size
     33318  page reclaims
         0  page faults
         0  swaps
         0  block input operations
         0  block output operations
        10  messages sent
        10  messages received
        30  signals received
       100  voluntary context switches
      1012  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!

        3.75 real         0.46 user         0.36 sys
  26664960  maximum resident set size
         0  average shared memory size
         0  average unshared data size
         0  average unshared stack size
     32776  page reclaims
       535  page faults
         0  swaps
       148  block input operations
         0  block output operations
        14  messages sent
        14  messages received
        29  signals received
       761  voluntary context switches
      1263  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

• Flag to disable ansi escaping for output
• HTML pretty printing
• encode body content in a specific format (JSON, YAML, etc)
• decode response based on Content-Type