arangojs
v9.1.0
Published
The official ArangoDB JavaScript driver.
Downloads
45,137
Readme
ArangoDB JavaScript Driver
The official ArangoDB JavaScript client for Node.js and the browser.
Links
Install
With npm or yarn
npm install --save arangojs
## - or -
yarn add arangojs
For browsers
When using modern JavaScript tooling with a bundler and compiler (e.g. Babel),
arangojs can be installed using npm
or yarn
like any other dependency.
You can also use jsDelivr CDN during development:
<script type="importmap">
{
"imports": {
"arangojs": "https://cdn.jsdelivr.net/npm/[email protected]/esm/index.js?+esm"
}
}
</script>
<script type="module">
import { Database } from "arangojs";
const db = new Database();
// ...
</script>
Basic usage example
Modern JavaScript/TypeScript with async/await and ES Modules:
import { Database, aql } from "arangojs";
const db = new Database();
const Pokemons = db.collection("my-pokemons");
async function main() {
try {
const pokemons = await db.query(aql`
FOR pokemon IN ${Pokemons}
FILTER pokemon.type == "fire"
RETURN pokemon
`);
console.log("My pokemans, let me show you them:");
for await (const pokemon of pokemons) {
console.log(pokemon.name);
}
} catch (err) {
console.error(err.message);
}
}
main();
Using a different database:
const db = new Database({
url: "http://127.0.0.1:8529",
databaseName: "pancakes",
auth: { username: "root", password: "hunter2" },
});
// The credentials can be swapped at any time
db.useBasicAuth("admin", "maplesyrup");
Old-school JavaScript with promises and CommonJS:
var arangojs = require("arangojs");
var Database = arangojs.Database;
var db = new Database();
var pokemons = db.collection("pokemons");
db.query({
query: "FOR p IN @@c FILTER p.type == 'fire' RETURN p",
bindVars: { "@c": "pokemons" },
})
.then(function (cursor) {
console.log("My pokemons, let me show you them:");
return cursor.forEach(function (pokemon) {
console.log(pokemon.name);
});
})
.catch(function (err) {
console.error(err.message);
});
Note: The examples throughout this documentation use async
/await
and other modern language features like multi-line strings and template tags.
When developing for an environment without support for these language features,
substitute promises for await
syntax as in the above example.
Compatibility
The arangojs driver is compatible with the latest stable version of ArangoDB available at the time of the driver release and remains compatible with the two most recent Node.js LTS versions in accordance with the official Node.js long-term support schedule. Versions of ArangoDB that have reached their end of life by the time of a driver release are explicitly not supported.
For a list of changes between recent versions of the driver, see the CHANGELOG.
Note: arangojs is only intended to be used in Node.js or a browser to access
ArangoDB from outside the database. If you are looking for the ArangoDB
JavaScript API for Foxx or for accessing ArangoDB
from within the arangosh
interactive shell, please refer to the documentation
of the @arangodb
module
and the db
object instead.
Error responses
If arangojs encounters an API error, it will throw an ArangoError
with
an errorNum
property indicating the ArangoDB error code and the code
property indicating the HTTP status code from the response body.
For any other non-ArangoDB error responses (4xx/5xx status code), it will throw
an HttpError
error with the status code indicated by the code
property.
If the server response did not indicate an error but the response body could
not be parsed, a regular SyntaxError
may be thrown instead.
In all of these cases the server response object will be exposed as the
response
property on the error object.
If the request failed at a network level or the connection was closed without receiving a response, the underlying system error will be thrown instead.
Common issues
Missing functions or unexpected server errors
Please make sure you are using the latest version of this driver and that the version of the arangojs documentation you are reading matches that version.
Changes in the major version number of arangojs (e.g. 7.x.y -> 8.0.0) indicate backwards-incompatible changes in the arangojs API that may require changes in your code when upgrading your version of arangojs.
Additionally please ensure that your version of Node.js (or browser) and ArangoDB are supported by the version of arangojs you are trying to use. See the compatibility section for additional information.
Note: As of June 2018 ArangoDB 2.8 has reached its End of Life and is no
longer supported in arangojs 7 and later. If your code needs to work with
ArangoDB 2.8 you can continue using arangojs 6 and enable ArangoDB 2.8
compatibility mode by setting the config option arangoVersion: 20800
to
enable the ArangoDB 2.8 compatibility mode in arangojs 6.
You can install an older version of arangojs using npm
or yarn
:
# for version 6.x.x
yarn add arangojs@6
# - or -
npm install --save arangojs@6
No code intelligence when using require instead of import
If you are using require
to import the arangojs
module in JavaScript, the
default export might not be recognized as a function by the code intelligence
of common editors like Visual Studio Code, breaking auto-complete and other
useful features.
As a workaround, use the arangojs
function exported by that module instead
of calling the module itself:
const arangojs = require("arangojs");
- const db = arangojs({
+ const db = arangojs.arangojs({
url: ARANGODB_SERVER,
});
Alternatively you can use the Database
class directly:
const arangojs = require("arangojs");
+ const Database = arangojs.Database;
- const db = arangojs({
+ const db = new Database({
url: ARANGODB_SERVER,
});
Or using object destructuring:
- const arangojs = require("arangojs");
+ const { Database } = require("arangojs");
- const db = arangojs({
+ const db = new Database({
url: ARANGODB_SERVER,
});
Error stack traces contain no useful information
Due to the async, queue-based behavior of arangojs, the stack traces generated when an error occur rarely provide enough information to determine the location in your own code where the request was initiated.
Using the precaptureStackTraces
configuration option, arangojs will attempt
to always generate stack traces proactively when a request is performed,
allowing arangojs to provide more meaningful stack traces at the cost of an
impact to performance even when no error occurs.
const { Database } = require("arangojs");
const db = new Database({
url: ARANGODB_SERVER,
+ precaptureStackTraces: true,
});
Note that arangojs will attempt to use Error.captureStackTrace
if available
and fall back to generating a stack trace by throwing an error. In environments
that do not support the stack
property on error objects, this option will
still impact performance but not result in any additional information becoming
available.
Node.js ReferenceError: window is not defined
If you compile your Node project using a build tool like Webpack, you may need to tell it to target the correct environment:
// webpack.config.js
+ "target": "node",
To support use in both browser and Node environments arangojs uses the
package.json
browser
field,
to substitute browser-specific implementations for certain modules.
Build tools like Webpack will respect this field when targetting a browser
environment and may need to be explicitly told you are targetting Node instead.
Node.js with self-signed HTTPS certificates
If you need to support self-signed HTTPS certificates in Node.js, you may have
to override the global fetch agent. At the time of this writing, there is no
official way to do this for the native fetch
implementation in Node.js.
However as Node.js uses the undici
module for its fetch
implementation
internally, you can override the global agent by adding undici
as a
dependency to your project and using its setGlobalDispatcher
as follows:
import { Agent, setGlobalDispatcher } from "undici";
setGlobalDispatcher(
new Agent({
ca: [
fs.readFileSync(".ssl/sub.class1.server.ca.pem"),
fs.readFileSync(".ssl/ca.pem"),
],
})
);
Although this is strongly discouraged, it's also possible to disable HTTPS certificate validation entirely, but note this has extremely dangerous security implications:
import { Agent, setGlobalDispatcher } from "undici";
setGlobalDispatcher(
new Agent({
rejectUnauthorized: false,
})
);
When using arangojs in the browser, self-signed HTTPS certificates need to be trusted by the browser or use a trusted root certificate.
Streaming transactions leak
When using the transaction.step
method it is important to be aware of the
limitations of what a callback passed to this method is allowed to do.
const collection = db.collection(collectionName);
const trx = db.transaction(transactionId);
// WARNING: This code will not work as intended!
await trx.step(async () => {
await collection.save(doc1);
await collection.save(doc2); // Not part of the transaction!
});
// INSTEAD: Always perform a single operation per step:
await trx.step(() => collection.save(doc1));
await trx.step(() => collection.save(doc2));
Please refer to the documentation of this method for additional examples.
Streaming transactions timeout in cluster
Example messages: transaction not found
, transaction already expired
.
Transactions have different guarantees in a cluster.
When using arangojs in a cluster with load balancing, you may need to adjust
the value of config.poolSize
to accommodate the number of transactions
you need to be able to run in parallel. The default value is likely to be too
low for most cluster scenarios involving frequent streaming transactions.
Note: When using a high value for config.poolSize
you may have
to adjust the maximum number of threads in the ArangoDB configuration using
the server.maximal-threads
option
to support larger numbers of concurrent transactions on the server side.
License
The Apache License, Version 2.0. For more information, see the accompanying LICENSE file.
Includes code from x3-linkedlist used under the MIT license.