arangors lite

arangors_lite is a fork of arangors by fMeow.

arangors is an intuitive rust client for ArangoDB, inspired by pyArango.

arangors enables you to connect with ArangoDB server, access to database, execute AQL query, manage ArangoDB in an easy and intuitive way, both async and plain synchronous code with any HTTP ecosystem you love.

Philosophy of arangors

arangors is targeted at ergonomic, intuitive and OOP-like API for ArangoDB, both top level and low level API for users' choice.

Overall architecture of ArangoDB:

databases -> collections -> documents/edges

In fact, the design of arangors just mimic this architecture, with a slight difference that in the top level, there is a connection object on top of databases, containing a HTTP client with authentication information in HTTP headers.

Hierarchy of arangors:

connection -> databases -> collections -> documents/edges

Features

By now, the available features of arangors are:

• make connection to ArangoDB
• get list of databases and collections
• fetch database and collection info
• create and delete database or collections
• full featured AQL query
• support both async and sync

Glance

Use Async or sync code

[dependencies]
## This one is async
arangors_lite = { version = "0.2" }
## This one is synchronous
arangors_lite = { version = "0.2", features = ["blocking"] }

Thanks to maybe_async, arangors can unify sync and async API and toggle with a feature gate. Arangors adopts async first policy.

By default reqwest uses OpenSSL. To use rustls you may disable default features and use the rustls feature:

[dependencies]
## This one uses openssl
arangors_lite = { version = "0.2" }
## This one rustls
arangors_lite = { version = "0.2", features = ["rustls"], default-features = false }

Connection

There is three way to establish connections:

• jwt
• basic auth
• no authentication

So are the arangors API.

Example:

• With authentication

use arangors_lite::Connection;

// (Recommended) Handy functions
let conn = Connection::establish_jwt("http://localhost:8529", "username", "password")
    .await
    .unwrap();
let conn = Connection::establish_basic_auth("http://localhost:8529", "username", "password")
    .await
    .unwrap();

• Without authentication, only use in evaluation setting

let conn = Connection::establish_without_auth("http://localhost:8529").await.unwrap();

Database && Collection

use arangors_lite::Connection;

let db = conn.db("test_db").await.unwrap();
let collection = db.collection("test_collection").await.unwrap();

AQL Query

All AQL query related functions are associated with database, as AQL query is performed at database level.

There are several way to execute AQL query, and can be categorized into two classes:

• batch query with cursor

  • aql_query_batch
  • aql_next_batch

• query to fetch all results

  • aql_str
  • aql_bind_vars
  • aql_query

This later ones provide a convenient high level API, whereas batch queries offer more control.

Typed or Not Typed

Note that results from ArangoDB server, e.x. fetched documents, can be strong typed given deserializable struct, or arbitrary JSON object with serde::Value.

#[derive(Deserialize, Debug)]
struct User {
    pub username: String,
    pub password: String,
}

// Typed
let resp: Vec<User> = db
    .aql_str("FOR u IN test_collection RETURN u")
    .await
    .unwrap();
// Not typed: Arbitrary JSON objects
let resp: Vec<serde_json::Value> = db
    .aql_str("FOR u IN test_collection RETURN u")
    .await
    .unwrap();

Batch query

arangors offers a way to manually handle batch query.

Use aql_query_batch to get a cursor, and use aql_next_batch to fetch next batch and update cursor with the cursor.

let aql = AqlQuery::new("FOR u IN @@collection LIMIT 3 RETURN u")
    .bind_var("@collection", "test_collection")
    .batch_size(1)
    .count(true);

// fetch the first cursor
let mut cursor = db.aql_query_batch(aql).await.unwrap();
// see metadata in cursor
println!("count: {:?}", cursor.count);
println!("cached: {}", cursor.cached);
let mut results: Vec<serde_json::Value> = Vec::new();
loop {
    if cursor.more {
        let id = cursor.id.unwrap().clone();
        // save data
        results.extend(cursor.result.into_iter());
        // update cursor
        cursor = db.aql_next_batch(id.as_str()).await.unwrap();
    } else {
        break;
    }
}
println!("{:?}", results);

Fetch All Results

There are three functions for AQL query that fetch all results from ArangoDB. These functions internally fetch batch results one after another to get all results.

The functions for fetching all results are listed as bellow:

aql_str

This function only accept a AQL query string.

Here is an example of strong typed query result with aql_str:

#[derive(Deserialize, Debug)]
struct User {
    pub username: String,
    pub password: String,
}

let result: Vec<User> = db
    .aql_str(r#"FOR i in test_collection FILTER i.username=="test2" return i"#)
    .await
    .unwrap();

aql_bind_vars

This function can be used to start a AQL query with bind variables.

use arangors_lite::{Connection, Document};

#[derive(Serialize, Deserialize, Debug)]
struct User {
    pub username: String,
    pub password: String,
}


let mut vars = HashMap::new();
let user = User {
    username: "test".to_string(),
    password: "test_pwd".to_string(),
};
vars.insert("user", serde_json::value::to_value(&user).unwrap());
let result: Vec<Document<User>> = db
    .aql_bind_vars(r#"FOR i in test_collection FILTER i==@user return i"#, vars)
    .await
    .unwrap();

aql_query

This function offers all the options available to tweak a AQL query. Users have to construct a AqlQuery object first. And AqlQuery offer all the options needed to tweak AQL query. You can set batch size, add bind vars, limit memory, and all others options available.

use arangors_lite::{AqlQuery, Connection, Cursor, Database};
use serde_json::value::Value;


let aql = AqlQuery::new("FOR u IN @@collection LIMIT 3 RETURN u")
    .bind_var("@collection", "test_collection")
    .batch_size(1)
    .count(true);

let resp: Vec<Value> = db.aql_query(aql).await.unwrap();
println!("{:?}", resp);

Contributing

Contributions and feed back are welcome following Github workflow.

License

arangors is provided under the MIT license. See LICENSE. An ergonomic ArangoDB client for rust.