https://github.com/nodecraft/spawnpoint-nats
NATS Plugin for Spawnpoint
https://github.com/nodecraft/spawnpoint-nats
nats spawnpoint
Last synced: 3 months ago
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NATS Plugin for Spawnpoint
- Host: GitHub
- URL: https://github.com/nodecraft/spawnpoint-nats
- Owner: nodecraft
- License: mit
- Created: 2017-05-04T15:59:55.000Z (almost 9 years ago)
- Default Branch: master
- Last Pushed: 2026-01-21T23:42:28.000Z (3 months ago)
- Last Synced: 2026-01-22T12:50:57.049Z (3 months ago)
- Topics: nats, spawnpoint
- Language: JavaScript
- Homepage: https://github.com/nodecraft/spawnpoint
- Size: 416 KB
- Stars: 0
- Watchers: 4
- Forks: 2
- Open Issues: 1
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
# spawnpoint-nats.js
[NATS](https://nats.io/) Plugin for [Spawnpoint](https://github.com/nodecraft/spawnpoint) on NPM
[](https://badge.fury.io/js/spawnpoint-nats)
[](https://david-dm.org/nodecraft/spawnpoint-nats)
[](https://github.com/nodecraft/spawnpoint-nats/actions?workflow=Test)
[](https://greenkeeper.io/)
## Installation
Make sure to install NATS and the plugin for Spawnpoint NATS separately. NATS is treated as a peer dependency so you can change version separately.
```npm i nats spawnpoint-nats```
## NATS Versions
- This module's version `2.x.x` is designed for a NATS server running `2.x`
- This module's version `1.x.x` is designed for a NATS server running `1.x`
## API
This api is mounted at `app.nats` to access these methods:
##### `app.nats.publish(subject, message, callback)`
Sends a message to a subscriber. Expects no response. Callback issued when message is sent to the NATS server. No guarantee of receipt.
- `subject` *string* - subject to publish message to
- `message` *object|array|string|buffer* - Message body for published message
- `callback` *function* - Optional callback fired when sent
##### `app.nats.request(subject, message, options, callback, updateCallback)`
Sends a message to a subscriber with the expectation of at least one reply. Main callback only listens for the final reply. Can get updates to provide realtime stats/progress and/or acknowledgments to reset timeouts. Returns event emitter for `update`, `ack`, `response`, & `timeout` events.
- `subject` *string* - subject to publish message to
- `message` *object|array|string|buffer* - Message body for published message
- `options` *object* - Options passed to `PUB` [method](http://nats.io/documentation/internals/nats-protocol/#PUB).
- `max` *number* - Number of replies to receive before unsubscribing from replies, optional
- `timeout` *number* - Number of ms to wait until firing a timeout error. If omitted it will default to config settings. Setting to falsey value will disable timeout
- `callback` *function* - Optional callback fired when final response is sent. Callback includes two arguments
- `err` *error|null* - If the response failed via timeout or was reported as an error from the response.
- `results` **object|array|string|buffer* - Response body
- `updateCallback` *function* - Optional callback fired when update is sent. Callback includes one argument
- `results` *object|array|string|buffer* - Response body
###### Example:
```javascript
app.nats.request('lookup', {
domain: "google.com"
}, function(err, results){
if(err){
return console.error('ERROR', err);
}
console.log('Lookup results', results);
}, function(update){
console.log('update', update);
});
```
##### `app.nats.subscribe(subject, options, callback, updateCallback)`
Sends a message to a subscriber with the expectation of at least one reply. Main callback only listens for the final reply. Can get updates to provide realtime stats/progress and/or acknowledgments to reset timeouts. Returns event emitter for `update`, `ack`, `response`, & `timeout` events.
- `subject` *string* - subject to subscribe to
- `options` *object* - Options passed to `PUB` [method](http://nats.io/documentation/internals/nats-protocol/#PUB).
- `queue` *string* - Name of queue to join
- `max` *number* - Maximum number of messages to receive before automatically unsubscribing.
- `noAck` *boolean* - Prevents automatic `ack` message when set to true. Defaults to false.
- `noPrefix` *string* - Prevents configurable prefix string from adding to subject. Defaults to false.
- `callback` *function* - callback fired when messages are received. Callback includes two arguments
- `response` *object|array|string|buffer* - Message body
- `handler` *eventEmitter* - Event emitter with helper methods to handle updates, acks, and replies.
- Emittable EVENTS - These events need to be emitted to send messages
- `ack` - timeout *int*: Resets the timeout for the request. If not timeout is specified it will reset the timer that was used by the requester. `timeout` is in ms.
- `update` - data *string*: Sends a message with data update the request. Also resets the timeout.
- `response` - err *error|null*, results *object|array|string|buffer*: Sends an error or response to the request
- Helper Methods - These methods are helper methods to make emitting the events above easier
- `ack()`: Tells the request to reset timeout, has no body or data to send
- `update(data *string*)`: Sends a message with data update the request. Also resets the timeout.
- `response(err *error|null*, results *object|array|string|buffer*)`: Sends an error or response to the request
- `subject` *string* - Copy of the message subject. Useful for wildcard subscriptions. Does not include prefix where applicable.
###### Example:
```javascript
app.nats.handle('lookup', {
queue: "dns.lookup"
}, function(msg, handler){
setTimeout(function(){
handler.ack();
}, 2500);
setTimeout(function(){
handler.update({
pending: true
});
}, 5000);
setTimeout(function(){
handler.response(null, msg);
}, 7500);
});
```