Crate elastic_types [−] [src]

Elasticsearch Core Types

An implementation of the core types in Elasticsearch documents.

Provides structs and traits for defining Elasticsearch type mapping, where correctness is enforced by Rust's type system.

Supported Versions

`elastic_types`	Elasticsearch
`0.x`	`5.x`

Usage

This crate is on crates.io.

There are two ways to reference elastic_types in your projects, depending on whether you're on the stable/beta or nightly channels.

Builds on nightly benefit from compile-time codegen for better performance and easier mapping definitions. The story on stable will be improved over time so it won't be a second-class citizen forever.

Nightly

To get started, add elastic_types and elastic_types_macros to your Cargo.toml:

[dependencies]
elastic_types = { version = "*", defeault-features = false, features = "nightly" }
elastic_types_macros = "*"

And reference it in your crate root:

#![feature(plugin)]
#![plugin(elastic_types_macros)]

#[macro_use]
extern crate elastic_types;

Stable

To get started, add elastic_types to your Cargo.toml:

[dependencies]
elastic_types = "*"

And reference it in your crate root:

extern crate elastic_types;

Any code examples that aren't compatible with both nightly and stable, like deriving mappings, have alternatives depending on the channel you're targeting.

A Complete Example

Before digging in to the API, consider the following complete example for defining and mapping a type called Article on nightly.

Our Cargo.toml specifies the dependencies as above:

[dependencies]
elastic_types = { version = "*", features = "nightly" }
elastic_types_macros = "*"

And our main.rs contains the following:

#![feature(plugin, custom_derive)]
#![plugin(serde_macros, elastic_types_macros)]
 
#[macro_use]
extern crate elastic_types;
extern crate serde;
 
use std::marker::PhantomData;
 
use elastic_types::prelude::*;
 
 
//Our main datatype, `article`
 
#[derive(Serialize, Deserialize, ElasticType)]
struct Article {
    pub id: i32,
    pub title: String,
    pub content: ElasticText<ContentMapping>,
    pub timestamp: Option<ElasticDate<EpochMillis, TimestampMapping<EpochMillis>>>,
    pub geoip: GeoIp
}
 
#[derive(Serialize, Deserialize, ElasticType)]
struct GeoIp {
    pub ip: std::net::Ipv4Addr,
    pub loc: ElasticGeoPoint<DefaultGeoPointFormat>
}
 
 
//Mappings for our datatype fields
 
text_mapping!(ContentMapping {
    fn analyzer() -> Option<&'static str> {
        Some("content_text")
    }
});
 
date_mapping!(TimestampMapping {
    fn null_value() -> Option<ElasticDate<F, Self>> {
        Some(ElasticDate::now())
    }
});
 
fn main() {
    println!("\"{}\":{{ {} }}", 
        Article::name(), 
        TypeMapper::to_string(Article::mapping()).unwrap()
    );
}

The above example defines a struct called Article with a few fields:

A default integer field called id
A default string field called title
A text field with a custom analyser called content
A date field with the epoch_millis format that defaults to the time the index was created called timestamp
An object field called GeoIp with default ip and geo_point fields.

Go ahead and run that sample and see what it outputs. In case you're interested, it'll look something like this (minus the whitespace):

"article": { 
    "properties": {
        "id":{
            "type": "integer"
        },
        "title": {
            "type":"text",
            "fields": {
                "keyword": {
                    "type": "keyword",
                    "ignore_above": 256
                }
            }
        },
        "content": {
            "type": "text",
            "analyzer": "content_text"
        },
        "timestamp": {
            "type": "date",
            "format": "epoch_millis",
            "null_value": "1435935302478"
        },
        "geoip": {
            "type": "nested",
            "properties": {
                "ip": {
                    "type": "ip"
                },
                "loc": {
                    "type": "geo_point"
                }
            }
        }
    }
}

The mapping is constructed by inspecting the type parameters of the fields on Article and GeoIp and serialised by serde.

Map Your Types

For mapping on stable, see here.

Derive ElasticType on your Elasticsearch-mappable types:

#[derive(Serialize, Deserialize, ElasticType)]
pub struct MyType {
    pub my_date: ElasticDate<DefaultDateFormat>,
    pub my_num: i32
}

This will generate a mapping type for you called {TypeName}Mapping, so in this case our mapping is called MyTypeMapping. You can then serialise the mapping as json:

let mapping = TypeMapper::to_string(MyTypeMapping).unwrap();

Which will output the following json:

{
    "properties": {
        "my_date": {
            "type": "date",
            "format": "basic_date_time"
        },
        "my_num": {
            "type": "integer"
        }
    }
}

Of course, structs that derive ElasticType can also be used as fields on other Elasticsearch types:

#[derive(Serialize, Deserialize, ElasticType)]
pub struct MyOtherType {
    pub my_type: MyType
}

Our mapping for MyOtherType then looks like:

{
    "properties": {
        "my_type": {
            "type": "nested",
            "properties": {
                "my_date": {
                    "type": "date",
                    "format": "basic_date_time"
                },
                "my_num": {
                    "type": "integer"
                }
            }
        }
    }
}

Elasticsearch doesn't differentiate between nullable types or collections, so it's also possible to derive mapping from Option or Vec types:

#[derive(Serialize, Deserialize, ElasticType)]
pub struct MyType {
    pub my_date: Option<ElasticDate<DefaultDateFormat>>,
    pub my_num: Vec<i32>
}

Which produces the same mapping as before. See the object mod for more mapping examples.

For mapping in rs-es, see the RsesMapper.

Types

Types in Elasticsearch are a combination of source and mapping. The source is the data (like 42 or "my string") and the mapping is metadata about how to interpret and use the data (like the format of a date string).

The approach elastic_types takes to types is to bundle the mapping up as a Zero Sized Type. This mapping type is then bound to a field as a generic parameter. For example:

ElasticString<DefaultStringMapping>

The source is a string and the mapping is DefaultStringMapping.

All Elasticsearch types implement the base ElasticType<M: ElasticFieldMapping<F>, F> trait where M is the mapping and F is a type-specific format.

The following table illustrates the types provided by elastic_types (links to the relevant mapping type):

Elasticsearch Type	Rust Type (Default Mapping)	Crate	Rust Type (Custom Mapping)	Format Type
`integer`	`i32`	`std`	`ElasticInteger<M>`	`()`
`long`	`i64`	`std`	`ElasticLong<M>`	`()`
`short`	`i16`	`std`	`ElasticShort<M>`	`()`
`byte`	`i8`	`std`	`ElasticByte<M>`	`()`
`float`	`f32`	`std`	`ElasticFloat<M>`	`()`
`double`	`f64`	`std`	`ElasticDouble<M>`	`()`
`keyword`	-	-	`ElasticKeyword<M>`	`()`
`text`	`String`	`std`	`ElasticText<M>`	`()`
`boolean`	`bool`	`std`	`ElasticBoolean<M>`	`()`
`ip`	`Ipv4Addr`	`std`	`ElasticIp<M>`	`()`
`date`	`DateTime<UTC>`	`chrono`	`ElasticDate<F, M>`	`DateFormat`
`geo_point`	`Point`	`geo`	`ElasticGeoPoint<F, M>`	`GeoPointFormat`
`geo_shape`	-	`geojson`	`ElasticGeoShape<M>`	`()`

The following sections explain this table.

Mapping

Having the mapping available at compile-time makes it easy to write efficient generic methods that use type mapping.

Where there's a std type that's equivalent to an Elasticsearch type (like i32 for integer), a default mapping is implemented for that type. That means you can use primitives in your structs and have them mapped to the correct type in Elasticsearch. If you want to provide your own mapping for a std type, there's also a struct provided by elastic_types that wraps the std type but also takes an explicit mapping (like ElasticInteger for i32).

Where there isn't a std type available (like date), an external crate is used and an implementation of that type is provided (like ElasticDate, which implements chrono::DateLike + chrono::TimeLike).

Formats

For some types (like ElasticDate), it's helpful to have an extra generic parameter that describes the format the data can take. For most types the format is (), because there aren't any alternative formats available.

Links

Reexports

pub extern crate chrono;

pub extern crate geo as georust;

pub extern crate geojson;

Modules

boolean	Implementation of the Elasticsearch `boolean` types.
date	Implementation of the Elasticsearch `date` type.
geo	Implementation of the Elasticsearch `geo` types.
ip	Implementation of the Elasticsearch `boolean` type.
mappers	Helper mappers for `ElasticType`.
mapping	Base requirements for type mappings.
number	Implementation of the Elasticsearch `number` types.
object	Requirements for mapping `user-defined` types.
prelude	Includes non-mapping types for all data types.
string	Implementation of the Elasticsearch `keyword` and `text` types.

Macros

boolean_mapping!	Define a `boolean` mapping.
boolean_ser!	Implement `serde` serialisation for a `boolean` mapping type.
byte_mapping!	Define a `byte` mapping.
date_mapping!	Define a `date` mapping for all formats.
date_ser!	Implement `serde` serialisation for a `date` mapping type.
double_mapping!	Define a `double` mapping.
float_mapping!	Define a `float` mapping.
geo_point_mapping!	Define a `geo_point` mapping for all formats.
geo_point_ser!	Implement `serde` serialisation for a `date` mapping type.
geo_shape_mapping!	Define a `geo_shape` mapping.
geo_shape_ser!	Implement `serde` serialisation for a `geo_shape` mapping type.
impl_date_fmt!	Implement `DateFormat` for the given type.
integer_mapping!	Define an `integer` mapping.
ip_mapping!	Define an `ip` mapping.
ip_ser!	Implement `serde` serialisation for a `geo_shape` mapping type.
keyword_mapping!	Define a `keyword` mapping.
keyword_ser!	Implement `serde` serialisation for a `keyword` mapping type.
long_mapping!	Define a `long` mapping.
number_ser!	Implement `serde` serialisation for a `geo_shape` mapping type.
object_mapping!	Define an `object` field mapping.
object_ser!
props_ser!
ser_field!
short_mapping!	Define a `short` mapping.
text_mapping!	Define a `text` mapping.
text_ser!	Implement `serde` serialisation for a `keyword` mapping type.
type_mapping!	Define an indexable `type` mapping.