# consulrs

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    <a href="https://crates.io/crates/consulrs">
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> An asynchronous Rust client library for the [Hashicorp Consul][1] API

The following features are currently supported:

* [Catalog](https://www.consul.io/api-docs/catalogv)
* [Checks](https://www.consul.io/api-docs/agent/check)
* [KV Store](https://www.consul.io/api-docs/kv)
* [Services](https://www.consul.io/api-docs/agent/service)
* [Sessions](https://www.consul.io/api-docs/session)

Additionally, all optional API features such as consistency modes, blocking, 
etc. are also supported. 

## Installation

Add `consulrs` as a dependency to your cargo.toml:
```
[dependencies]
consulrs = "0.1.0"
```

## Usage

### Basic

The client is used to configure the connection to Consul and is required to be
passed to all API calls for execution. Behind the scenes it uses an asynchronous
client from [Reqwest](https://docs.rs/reqwest/) for communicating to Consul.

```rust
use consulrs::client::{ConsulClient, ConsulClientSettingsBuilder};

// Create a client
let client = ConsulClient::new(
    ConsulClientSettingsBuilder::default()
        .address("https://127.0.0.1:8200")
        .build()
        .unwrap()
).unwrap();
```

The client supports all features required to interact with a production Consul
service including the option to specify ACL tokens as well as client and CA
certificates.


### Using KV store

```rust
use std::convert::TryInto;
use consulrs::kv;

// Set `mykey` to "myvalue"
kv::set(&client, "mykey", b"myvalue", None).await;

// Read `mykey`
let mut res = kv::read(&client, "mykey", None).await.unwrap();

// All responses are base64 encoded by default. The below attempts to coerce
// the response back into a UTF-8 encoded string.
let mykey: String = res.response.pop().unwrap().value.unwrap().try_into().unwrap();

assert_eq!(mykey, "myvalue".to_string());
```

### Registering a service

```rust
use consulrs::api::check::common::AgentServiceCheckBuilder;
use consulrs::api::service::requests::RegisterServiceRequest
use consulrs::service;

// Create a service named "my_service" with a health check that queries the
// service via HTTP every 10 seconds.
service::register(
    &client,
    "my_service",
    Some(
        RegisterServiceRequest::builder()
            .address("http://myservice.lab.com")
            .port(1234)
            .check(
                AgentServiceCheckBuilder::default()
                    .name("health_check")
                    .interval("10s")
                    .http("http://myservice.lab.com/health")
                    .status("passing")
                    .build()
                    .unwrap(),
            ),
    ),
)
.await;
```

See the [examples](examples) directory for additional examples.


## Error Handling and Tracing

All errors generated by this crate are wrapped in the `ClientError` enum 
provided by the crate. API errors are captured and returned as their own
variant including the response code and error message from the server. 
Connection related errors from `rustify` are wrapped and returned as a single 
variant.

All top level API operations are instrumented with `tracing`'s `#[instrument]`
attribute.

## Testing

See the the [tests](tests) directory for tests. Run tests with `cargo test`.

**Note**: All tests rely on bringing up a local Consul development server using
Docker. In order to run tests Docker must be running locally (Docker Desktop 
works).

## Contributing

Check out the [issues][2] for items needing attention or submit your own and 
then:

1. Fork the repo (https://github.com/jmgilman/consulrs/fork)
2. Create your feature branch (git checkout -b feature/fooBar)
3. Commit your changes (git commit -am 'Add some fooBar')
4. Push to the branch (git push origin feature/fooBar)
5. Create a new Pull Request

[1]: https://www.consul.io/
[2]: https://github.com/jmgilman/consulrs/issues