0.5.1 |
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#16 in #arango-db
200KB
3K
SLoC
arangors
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
TODO
-
(Done) Milestone 0.1.x
Synchronous connection based on
reqwest
and full featured AQL query. -
(X) Milestone 0.2.x
Fill the unimplemented API in
Connection
,Database
,Collection
andDocument
.In this stage, all operations available for database, collection and document should be implemented.Well, I am too lazy to fill all API, as the AQL syntax suffices in most cases. Maybe fulfill this goal in 0.4.x .
-
(Done) Milestone 0.3.x
Implement both sync and async client. Also, offers a way to use custom HTTP client ecosystem.
-
(WIP) Milestone 1.0.x
Provides the API related to:
- (X) Graph Management
- (X) Index Management
- ( ) User Management
In this stage, all operations available for database, collection and document should be implemented.
Glance
Use Different HTTP Ecosystem, Regardless of Async or Sync
You can switch to different HTTP ecosystem with a feature gate, or implement the Client yourself (see examples).
Currently out-of-box supported ecosystem are:
reqwest_async
reqwest_blocking
surf_async
By default, arangors
use reqwest_async
as underling HTTP Client to
connect with ArangoDB. You can switch other ecosystem in feature gate:
[dependencies]
arangors = { version = "0.4", features = ["surf_async"], default-features = false }
Or if you want to stick with other ecosystem that are not listed in the
feature gate, you can get vanilla arangors
without any HTTP client
dependency:
[dependencies]
## This one is async
arangors = { version = "0.4", default-features = false }
## This one is synchronous
arangors = { version = "0.4", features = ["blocking"], default-features = false }
Thanks to maybe_async
, arangors
can unify sync and async API and toggle
with a feature gate. Arangors adopts async first policy.
Connection
There is three way to establish connections:
- jwt
- basic auth
- no authentication
So are the arangors
API.
Example:
- With authentication
use arangors::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::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::builder()
.query("FOR u IN @@collection LIMIT 3 RETURN u")
.bind_var("@collection", "test_collection")
.batch_size(1)
.count(true)
.build();
// 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::{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::{AqlQuery, Connection, Cursor, Database};
use serde_json::value::Value;
let aql = AqlQuery::builder()
.query("FOR u IN @@collection LIMIT 3 RETURN u")
.bind_var("@collection", "test_collection")
.batch_size(1)
.count(true)
.build();
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.
Dependencies
~3–18MB
~272K SLoC