kcupkcup is a single file server. It responds to every GET request it receives with the content of a given file (specified by ENV, CLI argument or STDIN), and for every other request (with any other HTTP method or path) it returns a 404.
kcup was invented to help with cases where a generally small file needs to be delivered at a certain path, for example MTA STS's /.well-known/mta-sts.txt. You can read more about this on the associated blog post.
BEWARE This project and repo is so simple that there aren't even any tests -- I may add some in the future after light use. The machinery (Makefile targets, CI integration, etc) is there for unit, integration and e2e tests, but there just are none. Despite there being no tests, it does "just work" has been benchmarked. Use at your own risk.
See also kcup-go
kcup only needs the path to a single file to run:
console
$ kcup -f <file path>
By default, kcup will serve the file at host 127.0.0.1 on port 5000. kcup can also take file content from STDIN like so:
```console
$ kcup < your file content
goes here
EOF
``` ```console
kcup 0.1.0 USAGE:
kcup [OPTIONS] FLAGS:
--help Prints help information
-V, --version Prints version information OPTIONS:
-f, --file | ENV variable | Default | Example | Description |
|------------------------------|-------------|-------------------------|--------------------------------------------------|
| The following targets are mostly useful for development, testing the current build, as most depend on ```console
$ make run < You enter some text
EOF
cargo run
Finished dev [unoptimized + debuginfo] target(s) in 0.04s
Running You can serve the example file in the repository with TLS as well Note that the example page is NOT included in the Keurig created a "K-Cup" brewing system that has become somewhat infamous. tl;dr | | As you might expect, I did not limit the processes and my machine is pretty beefy: 6 physical cores (12 hyper threads) and 32GB of RAM so these processes got as much room as they cared to use.
Usage
Environment Variables
HOST | 127.0.0.1 | 0.0.0.0 | The host on which kcup will listen |
| PORT | 5000 | 3000 | The port on whcih kcup will listen |
| STDIN_READ_TIMEOUT_SECONDS | 60 | 10 | The amount of seconds to try and read from STDIN |
| FILE | N/A | /path/to/your/file | The path to the file that will be served |
| TLS_KEY | N/A | /path/to/your/tls.key | Path to a file contains a PEM-encoded TLS key |
| TLS_CERT | N/A | /path/to/your/tls.crt | Path to a file contains CA cert(s) |Useful Makefile targets
cargo run.Running the current build of
kcup with HEREDOCs
target/debug/kcup
[2021-05-09T02:51:58Z INFO kcup] Server configured to run @ [127.0.0.1:5000]
[2021-05-09T02:51:58Z INFO kcup] No file path provided, waiting for input on STDIN (max 60 seconds)...
[2021-05-09T02:51:58Z INFO kcup] Successfully read input from STDIN
[2021-05-09T02:51:58Z INFO kcup] Read [16] characters
[2021-05-09T02:51:58Z INFO kcup] Starting HTTP server...
```Serve the example file in the repository
console
$ make example
console
$ make example-tls
kcup binary, you have to bring your own file to serve at production time.FAQ
Why is this project named "kcup"?
Alternatives
miniservekcup is about 2x faster than miniserve, which is expected as it does much less.miniserve is a project that aims to serve files and directories over HTTP that was suggested on reddit by /u/vlmutolo. Since miniserve is also capable of serving a single file I've tested it gainst kcup with the usual wrk command and here are the results tabulated. Roughly by running the following:console
$ kcup -f /tmp/testfiles/file-1M &
$ miniserve /tmp/testfiles/file-1M -p 5001 &
$ wrk -t12 -c400 -d30s --latency http://127.0.0.1:5000/any/path/will/work # a few times
$ wrk -t12 -c400 -d30s --latency http://127.0.0.1:5001 # a few times
kcup | miniserve |
|------------------------------------|--------|-------------|
| Latency 50% (ms) | 21.09 | 83.94 |
| Latency 75% (ms) | 31.04 | 95.73 |
| Latency 90% (ms) | 40.81 | 107.23 |
| Latency 99% (ms) | 58.54 | 129.38 |
| (Thread stats) Latency avg (ms) | 23.29 | 84.94 |
| (Thread stats) Latency stddev (ms) | 12.57 | 17.11 |
| (Thread stats) Latency max (ms) | 120.18 | 182.87 |
| Request/sec | 11,900 | 4599 |
| Trasfer/sec (MB) | 1162 | 450 |kcup does so little (though there are some feature differences in the overlap) that it performs roughly 2x as well as miniserve.