• Stars
    star
    166
  • Rank 227,705 (Top 5 %)
  • Language
    Ruby
  • License
    MIT License
  • Created over 14 years ago
  • Updated over 7 years ago

Reviews

There are no reviews yet. Be the first to send feedback to the community and the maintainers!

Repository Details

Redis based queues and workers.

Ost

Redis based queues and workers.

Ost Cafe, by Arancia Project

Description

Ost makes it easy to enqueue object ids and process them with workers.

Say you want to process video uploads. In your application you will have something like this:

Ost[:videos_to_process].push(@video.id)

Then, you will have a worker that will look like this:

require "ost"

Ost[:videos_to_process].each do |id|
  # Do something with it!
end

Usage

Ost uses a lightweight Redis client called Redic. To connect to a Redis database, you will need to set an instance of Redic, with a URL of the form redis://:<passwd>@<host>:<port>/<db>.

You can customize the connection by calling Ost.redis=:

require "ost"

Ost.redis = Redic.new("redis://127.0.0.1:6379")

Then you only need to refer to a queue for it to pop into existence:

require "ost"

Ost.redis = Redic.new("redis://127.0.0.1:6379")

Ost[:rss_feeds] << @feed.id

Ost defaults to a Redic connection to redis://127.0.0.1:6379. The example above could be rewritten as:

require "ost"

Ost[:rss_feeds] << @feed.id

A worker is a Ruby file with this basic code:

require "ost"

Ost[:rss_feeds].each do |id|
  # ...
end

It will pop items from the queue as soon as they become available. It uses BRPOPLPUSH with a timeout that can be specified with the OST_TIMEOUT environment variable.

Note that in these examples we are pushing numbers to the queue. As we have unlimited queues, each queue should be specialized and the workers must be smart enough to know what to do with the numbers they pop.

Available methods

Ost[:example].push item, Ost[:some_queue] << item: add item to the :example queue.

Ost[:example].pop { |item| ... }, Ost[:example].each { |item| ... }: consume item from the :example queue. If the block doesn't complete successfully, the item will be left at a backup queue.

Ost.stop: halt processing for all queues.

Ost[:example].stop: halt processing for the example queue.

Failures

Ost stores in-process items in backup queues. That allows the developer to deal with exceptions in a way that results adequate for his application.

There is one backup queue for each worker, with the following convention for naming the key in Redis: given a worker using the :events queue, running in the hostname domU-12-31-39-04-49-C7 with the process id 28431, the key for the backup queue will be ost:events:domU-12-31-39-04-49-C7:28431.

Here's the explanation for each part:

  • ost: namespace for all Ost related keys.
  • events: name of the queue.
  • domU-12-31-39-04-49-C7: hostname of the worker.
  • 28431: process id of the worker.

Priorities

There's no concept of priorities, as each queue is specialized and you can create as many as you want. For example, nothing prevents the creation of the :example_high_priority or the :example_low_priority queues.

Differences with Delayed::Job and Resque

Both Delayed::Job and Resque provide queues and workers (the latter using Redis). They provide dumb workers that process jobs, which are specialized for each task. The specialization takes place in the application side, and the job is serialized and pushed into a queue.

Ost, by contrast, just pushes numbers into specialized queues, and uses workers that are subscribed to specific queues and know what to do with the items they get. The total sum of logic is about the same, but there's less communication and less data transfer with Ost.

Installation

$ gem install ost

More Repositories

1

cuba

Rum based microframework for web development.
Ruby
1,438
star
2

ohm

Object-Hash Mapping for Redis
Ruby
1,390
star
3

micromachine

Minimal Finite State Machine
Ruby
522
star
4

clac

Command-line, stack-based calculator with postfix notation
C
350
star
5

map

Map lines from stdin to commands
C
221
star
6

mote

Minimum Operational Template
Ruby
217
star
7

nest

Generate nested namespaced keys for key-value databases.
Ruby
185
star
8

toro

Tree oriented routing
Crystal
144
star
9

syro

Simple router for web applications
Ruby
135
star
10

cargo

Require libraries without cluttering your namespace.
Ruby
127
star
11

scrivener

Validation frontend for models.
Ruby
124
star
12

clap

Command line argument parsing
Ruby
90
star
13

ohm-crystal

Ohm for Crystal
Crystal
71
star
14

disque-rb

Disque client for Ruby
Ruby
68
star
15

gs

Gemset management
Ruby
67
star
16

totp

Time-based One-Time Passwords
Ruby
44
star
17

mailcat

Fake SMTP server that prints emails to stdout
C
38
star
18

chen

Change directory entries with your text editor
C
37
star
19

spawn

A ridiculously simple fixtures replacement for your web framework of choice.
Ruby
36
star
20

finist

Redis based Finite State Machine
Ruby
36
star
21

redisurl

Connect to Redis using a REDIS_URL and the redigo client.
Go
33
star
22

hart

Hash router
Ruby
24
star
23

stal-ruby

Set algebra solver for Redis
Ruby
22
star
24

redisent

Sentinels aware Redis client.
Ruby
22
star
25

relay

Relay commands over SSH
Ruby
21
star
26

resp

Lightweight RESP client for Lua
Lua
21
star
27

lomo

Apply a lomo filter to your pictures from the command line using ImageMagick.
Ruby
19
star
28

terco

Obstinate DNS
Ruby
16
star
29

override

The as-simple-as-possible-but-not-simpler stubbing library.
Ruby
16
star
30

ox

Skeleton for a Cuba-based JSON API.
Ruby
16
star
31

nido

Structured keys helper
Ruby
14
star
32

syro-demo

Demo application with Syro
Ruby
14
star
33

resp-crystal

Lightweight RESP client
Crystal
14
star
34

mt

Mail tester daemon.
Ruby
13
star
35

stringent

Generate a string with a target entropy
Ruby
12
star
36

rediscan

Scanner for Redis keyspace
Ruby
12
star
37

hypertext

Hypertext authoring with Ruby
Ruby
11
star
38

filmo

A single page presentation tool.
11
star
39

cuba-book

Cuba Book
11
star
40

sc

List of HTTP status codes.
Ruby
11
star
41

finist.lua

Redis based Finite State Machine
Lua
10
star
42

drawer

Ultra slim file-based cache
Ruby
10
star
43

nest-crystal

Object Oriented Keys for Redis
Crystal
9
star
44

basica

Basic authentication library.
Ruby
8
star
45

rino

Remove a file by its inode number
C
7
star
46

seg.rb

Segment matcher for paths
Ruby
7
star
47

seg

Segment matcher for paths
Crystal
7
star
48

trim

Read from stdin and remove a prefix from each line
C
7
star
49

tas

Trees as strings
Ruby
6
star
50

stal

Set algebra solver for Redis
Lua
6
star
51

pac

Package management for Lua libraries.
Shell
6
star
52

prep

Read from stdin and prepend a string to each line while preserving identation.
C
6
star
53

m4s2

Static Site Generator
HTML
5
star
54

contract

Contract helper
Ruby
5
star
55

stal-crystal

Set algebra solver for Redis
Crystal
5
star
56

loco

Lines of code counter
C
4
star
57

ook

Object Oriented Keys for Redis
Ruby
4
star
58

walk

Walk a directory tree and print the name of every regular file
C
4
star
59

rel

Ruby client for the Bandicoot database.
Ruby
4
star
60

textorama

Text slides for the terminal
Shell
4
star
61

homebrew-tools

Formulae for Homebrew
Ruby
4
star
62

rediscan.lua

Scanner for Redis keyspace in Lua
Lua
3
star
63

seg.go

Segment matcher for paths
Go
3
star
64

look

Add a vendor directory to your load path.
Ruby
3
star
65

app

Cuba application template for gn, the file generator.
Ruby
2
star
66

packer

Require different versions of the same Cargo-compatible gem
Ruby
2
star
67

tele.sh

2
star
68

ers

AWK script easy replacements in templates
Awk
2
star
69

soveran.github.io

2
star
70

filter

Workflow template for gn.
Ruby
1
star
71

remoto

Ruby
1
star
72

gem

Gem template for gn, the file generator.
Ruby
1
star
73

ohm-scripts

Lua scripts for Ohm compatible libraries
Lua
1
star
74

ostgo

Ost client.
Go
1
star
75

miga

Breadcrumb name of the working directory
C
1
star