JavaScript API
You can use ArangoDB’s JavaScript interface on the server-side as well as in ArangoDB’s shell to interact with the server using the JavaScript language
The JavaScript API is available on the server-side in the following contexts:
- Foxx microservices
- User-defined AQL functions
- JavaScript Transactions
- Emergency console (
arangod --console
)
Running on the server-side means that the code runs directly inside of the arangod process, bypassing the HTTP API. In cluster deployments, the code is executed on a Coordinator.
The JavaScript API is also available in the ArangoDB Shell client tool:
It communicates with the server via the HTTP API.
Usage example
The key element for using the JavaScript API is the
db
object, which is available by default
in arangosh and can be imported in server-side JavaScript code from the
@arangodb
module.
// Import the db object (only in server-side contexts)
let db = require("@arangodb").db;
The db
object lets you access and manage databases, for example:
// Create a new database
db._createDatabase("myDB");
// Make it the current database
db._useDatabase("myDB");
print(`Database context: ${ db._name() }`);
You can also work with collections and Views using the db
object.
Accessing a collection returns a collection object
and accessing a View returns a view object.
// Create a new collection. Returns a collection object
let coll = db._create("collection");
// Create a new arangosearch View. Returns a view object
let view = db._createView("view", "arangosearch", { links: { collection: { includeAllFields: true } } });
To obtain a reference to a collection or View again, you can use multiple ways:
coll = db._collection("collection");
view = db._view("view");
// or
coll = db.collection;
view = db.view;
You can create documents via a collection object. You can use arbitrary JavaScript code to generate data.
// Create single documents using both available methods.
// Returns an object with the document metadata (the _id, _key, and _rev attributes)
coll.save({ value: "foo" });
coll.insert({ value: "bar" });
// Create an array of objects and create multiple documents at once
let arr = [];
for (let i = 1; i < 100; i++) {
arr.push({ value: i });
}
coll.save(arr);
Indexes can also be created via a collection object.
// Create an index for the collection
coll.ensureIndex({ type: "persistent", fields: ["value"] });
To query the data in the current database, use the db
object. Executing an
AQL query returns a cursor object.
// Run an AQL query. Returns a cursor object
let cursor = db._query(`FOR doc IN collection FILTER doc.value >= "bar" RETURN doc`);
cursor.toArray();
// Import the aql query helper (only in server-side contexts)
const aql = require("@arangodb").aql;
// Run an AQL query using the query helper to use variables as bind parameters
let limit = 5;
db._query(aql`FOR doc IN ${ coll } LIMIT ${ limit } RETURN doc`).toArray();
See the full reference documentation for the common objects returned by the
@arangodb
module for details:
JavaScript Modules
ArangoDB uses a Node.js-compatible module system. You can use the function
require()
in order to load a module or library. It returns the exported
variables and functions of the module.
The following global variables are available in arangosh and all server-side JavaScript contexts in ArangoDB:
global
process
console
Buffer
__filename
__dirname
ArangoDB-specific modules
There is a large number of ArangoDB-specific modules using the @arangodb
namespace. Some of these modules are for internal use by ArangoDB itself.
You can use the following modules as an end-user:
@arangodb provides direct access to the database and its collections.
@arangodb/analyzers provides an interface to manage ArangoSearch Analyzers.
AQL related modules:
@arangodb/aql/queries offers methods to track and kill AQL queries.
@arangodb/aql/cache allows to control the AQL query caching feature.
@arangodb/aql/explainer provides methods to debug, explain and profile AQL queries.
@arangodb/aql/functions provides an interface to (un-)register user-defined AQL functions.
@arangodb/crypto provides various cryptography functions including hashing algorithms.
@arangodb/foxx is the namespace providing the various building blocks of the Foxx microservice framework.
- @arangodb/locals is a helper module to use Foxx together with Webpack.
Graph-related modules:
@arangodb/general-graph implements a graph management interface for named graphs.
@arangodb/smart-graph provides management features for SmartGraphs
@arangodb/satellite-graph provides management features for SatelliteGraphs
@arangodb/enterprise-graph provides management features for EnterpriseGraphs
@arangodb/graph-examples/example-graph can load example graphs (creates collections, populates them with documents and creates named graphs)
@arangodb/request provides the functionality for making synchronous HTTP/HTTPS requests.
@arangodb/tasks implements task management methods
@arangodb/users provides an interface for user management.
@arangodb/pregel provides an interface for Pregel management.
Node-compatibility modules
ArangoDB supports a number of modules for compatibility with Node.js, including:
assert implements basic assertion and testing functions.
buffer implements a binary data type for JavaScript.
console is a well known logging facility to all the JavaScript developers. ArangoDB implements most of the Console API , with the exceptions of profile and count.
events implements an event emitter.
fs provides a file system API for the manipulation of paths, directories, files, links, and the construction of file streams. ArangoDB implements most Filesystem/A functions.
module provides direct access to the module system.
path implements functions dealing with filenames and paths.
punycode implements conversion functions for punycode encoding.
querystring provides utilities for dealing with query strings.
stream provides a streaming interface.
string_decoder implements logic for decoding buffers into strings.
url provides utilities for URL resolution and parsing.
util provides general utility functions like
format
andinspect
.
Additionally ArangoDB provides partial implementations for the following modules:
net
: onlyisIP
,isIPv4
andisIPv6
.process
: onlyenv
andcwd
; stubs forargv
,stdout.isTTY
,stdout.write
,nextTick
.timers
: stubs forsetImmediate
,setTimeout
,setInterval
,clearImmediate
,clearTimeout
,clearInterval
andref
.tty
: onlyisatty
(always returnsfalse
).vm
: onlyrunInThisContext
.
The following Node.js modules are not available at all:
child_process
cluster
constants
crypto
(but see@arangodb/crypto
)dgram
dns
domain
http
(but see@arangodb/request
)https
os
sys
tls
v8
zlib