# elasticsearch   [![Latest Version]][crates.io] [![Docs]][docs.rs] [![Apache-2 licensed]][license]
[Latest Version]: https://img.shields.io/crates/v/elasticsearch.svg
[crates.io]: https://crates.io/crates/elasticsearch
[Docs]: https://docs.rs/elasticsearch/badge.svg
[docs.rs]: https://docs.rs/elasticsearch
[Apache-2 licensed]: https://img.shields.io/crates/l/elasticsearch.svg
[license]: ./LICENSE.txt
Official Rust Client for [Elasticsearch](https://github.com/elastic/elasticsearch).
Full documentation is available at https://docs.rs/elasticsearch
The project is still very much a _work in progress_ and in an _alpha_ state;
input and contributions welcome!
## Compatibility
The Elasticsearch Rust client is forward compatible; meaning that the client supports communicating with greater minor versions of Elasticsearch. Elasticsearch language clients are also backwards compatible with lesser supported minor Elasticsearch versions.
## Features
The following are a list of Cargo features that can be enabled or disabled:
- **native-tls** *(enabled by default)*: Enables TLS functionality provided by `native-tls`.
- **rustls-tls**: Enables TLS functionality provided by `rustls`.
- **beta-apis**: Enables beta APIs. Beta APIs are on track to become stable and permanent features. Use them with
caution because it is possible that breaking changes are made to these APIs in a minor version.
- **experimental-apis**: Enables experimental APIs. Experimental APIs are just that - an experiment. An experimental
API might have breaking changes in any future version, or it might even be removed entirely. This feature also
enables `beta-apis`.
## Getting started
The client exposes all Elasticsearch APIs as associated functions, either on
the root client, `Elasticsearch`, or on one of the _namespaced clients_, such as `Cat`, `Indices`, etc. The _namespaced clients_
are based on the grouping of APIs within the [Elasticsearch](https://github.com/elastic/elasticsearch/tree/master/rest-api-spec) and [X-Pack](https://github.com/elastic/elasticsearch/tree/master/x-pack/plugin/src/test/resources/rest-api-spec/api) REST API specs from which much of the client is generated.
All API functions are `async` only, and can be `await`ed.
### Installing
Add `elasticsearch` crate and version to Cargo.toml. Choose the version
that is compatible with the version of Elasticsearch you're using
```toml
[dependencies]
elasticsearch = "8.5.0-alpha.1"
```
The following _optional_ dependencies may also be useful to create requests and read responses
```toml
serde = "~1"
serde_json = "~1"
```
----
#### Async support with tokio
The client uses [`reqwest`](https://crates.io/crates/reqwest) to make HTTP calls, which internally uses
the [`tokio`](https://crates.io/crates/tokio) runtime for async support. As such, you may require to take a dependency on `tokio`
in order to use the client. For example, in Cargo.toml, you may need the following dependency,
```toml
tokio = { version = "*", features = ["full"] }
```
and to attribute async main function with `#[tokio::main]`
```rust,no_run
#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
// your code ...
Ok(())
}
```
and attribute test functions with `#[tokio::test]`
```rust,no_run
#[tokio::test]
async fn my_test() -> Result<(), Box<dyn std::error::Error>> {
// your code ...
Ok(())
}
```
----
### Create a client
Build a transport to make API requests to Elasticsearch using the `TransportBuilder`,
which allows setting of proxies, authentication schemes, certificate validation, and
other transport related settings.
To create a client to make API calls to Elasticsearch running on `http://localhost:9200`
```rust,no_run
use elasticsearch::Elasticsearch;
fn main() {
let client = Elasticsearch::default();
}
```
Alternatively, you can create a client to make API calls against Elasticsearch running on a specific url
```rust,no_run
use elasticsearch::{
Elasticsearch, Error,
http::transport::Transport
};
fn main() -> Result<(), Error> {
let transport = Transport::single_node("https://example.com")?;
let client = Elasticsearch::new(transport);
Ok(())
}
```
If you're running against an Elasticsearch deployment in [Elastic Cloud](https://www.elastic.co/cloud/),
a client can be created using a [Cloud ID](https://www.elastic.co/guide/en/cloud/current/ec-cloud-id.html)
and credentials retrieved from the Cloud web console
```rust,no_run
use elasticsearch::{
auth::Credentials,
Elasticsearch, Error,
http::transport::Transport,
};
fn main() -> Result<(), Error> {
let cloud_id = "cluster_name:Y2xvdWQtZW5kcG9pbnQuZXhhbXBsZSQzZGFkZjgyM2YwNTM4ODQ5N2VhNjg0MjM2ZDkxOGExYQ==";
// can use other types of Credentials too, like Bearer or ApiKey
let credentials = Credentials::Basic("<username>".into(), "<password>".into());
let transport = Transport::cloud(cloud_id, credentials)?;
let client = Elasticsearch::new(transport);
Ok(())
}
```
More control over how a `Transport` is built can be
achieved using `TransportBuilder` to build a transport, and
passing it to `Elasticsearch::new()` create a new instance of `Elasticsearch`
```rust,no_run
use url::Url;
use elasticsearch::{
Error, Elasticsearch,
http::transport::{TransportBuilder,SingleNodeConnectionPool},
};
fn main() -> Result<(), Error> {
let url = Url::parse("https://example.com")?;
let conn_pool = SingleNodeConnectionPool::new(url);
let transport = TransportBuilder::new(conn_pool).disable_proxy().build()?;
let client = Elasticsearch::new(transport);
Ok(())
}
```
### Making API calls
The following will execute a `POST` request to `/_search?allow_no_indices=true` with
a JSON body of `{"query":{"match_all":{}}}`
```rust,no_run
use elasticsearch::{Elasticsearch, Error, SearchParts};
use serde_json::{json, Value};
#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
let client = Elasticsearch::default();
// make a search API call
let search_response = client
.search(SearchParts::None)
.body(json!({
"query": {
"match_all": {}
}
}))
.allow_no_indices(true)
.send()
.await?;
// get the HTTP response status code
let status_code = search_response.status_code();
// read the response body. Consumes search_response
let response_body = search_response.json::<Value>().await?;
// read fields from the response body
let took = response_body["took"].as_i64().unwrap();
Ok(())
}
```
The client provides functions on each API builder struct
for all query string parameters available for that API. APIs with multiple
URI path variants, where some can contain parts parameters, are modelled as enums.
`Elasticsearch` also has an async `send` function on the root that allows sending an
API call to an endpoint not represented as an API function, for example, experimental
and beta APIs
```rust,no_run
use elasticsearch::{http::Method, Elasticsearch, Error, SearchParts};
use http::HeaderMap;
use serde_json::Value;
#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
let client = Elasticsearch::default();
let body = b"{\"query\":{\"match_all\":{}}}";
let response = client
.send(
Method::Post,
SearchParts::Index(&["tweets"]).url().as_ref(),
HeaderMap::new(),
Option::<&Value>::None,
Some(body.as_ref()),
None,
)
.await?;
Ok(())
}
```
## License
This is free software, licensed under [The Apache License Version 2.0.](LICENSE.txt).