# Licensed
[](https://travis-ci.org/ChrisMacNaughton/licensed)
[](https://coveralls.io/github/ChrisMacNaughton/licensed?branch=master)
Licensed is a library for adding digitally signed licenses to
your binary projects in a simple, extensible manner. In addition
to providing library functions for usei n your code, it provides
key generation and license signing binaries in the crate.
## Usage
To use `licensed`, you will need to generate keys to use for your
signing. These keys should be kept private as they are used to
proove that a license is valid.
If you want to generate keys in the example directory, you can
invioke `gen_keys` with a single argument, as shown below through
the `cargo run` command:
cargo run --bin=gen_keys -- examples
The above command will generatae two files in the target directory:
1. `private.pks`
2. `public.pks`
`private.pks` is actually the complete key material for the keys,
but is accompanied by `public.pks` as well to make including the
public key material into a destination binary easier.
`licensed` expects a certain format for its license files, such as:
```json
{
"features": [
"string key",
"another feature"
],
"expires": "2014-11-28T12:00:09Z"
}
```
`expires`, shown above, is an optional field that will be checked,
if present to ensure license validity.
Once you have the above file saved into, for example, `license.json`,
you can run:
gen_license license.json $KEY_PATH/private.pks $OUTPUT_PATH
The generated file at `$OUTPUT_PATH` will look like the above json with a null byte and the signature appended.
Validating a license in your binary is as simple as:
```rust
let filename = "path/to/license";
let license_file = read(filename)?;
let license = licensed::License::new(&license_file)
.with_public_key(&PUBLIC_KEY)
.build()?;
if license.valid() {
println!("The providded license is valid");
} else {
println!("The provided license is invalid");
}
```