taggable-via-redis

This is a rewrite of sintaxi's node-redis-tag. Following changes have been made:

• unify callback signature to callback(err, results)
• fix bug in set() that callback not fired when set identical tags
• add arugments checking
• change the implementation to statis methods

taggable-via-redis

Tagging is the perfect job for redis wouldn't you agree? This library makes it easy to implement a tagging system into any node appication. It has only 4 public methods and sets up all the associations for you.

Instalation

I always recomend you bundle your dependencies with your application. To do this, create a package.json file in the root of your project with the minimum information...

{
  "dependencies": {
    "taggable-via-redis": "latest"
  }
}

Then run the following command using npm...

npm install

OR, if you just want to start playing with the library run...

npm install taggable-via-redis

Test

npm test

Docs

To create a taggable object we must first require the library and then instantiate a new Taggable object. A taggable object can be any model in your system. For example: book, post, person, etc.

var taggable = require("taggable-via-redis")
taggable.init()

Now we have 4 methods on the bookTagger object that give us tagging abilities.

init options

• prefix -- [optional] redis key prefix
• redisClient -- [optional] use existing redis client, when override redisPort and redisHost options

set(moduleName, id, tags, [scope,] callback)

The set method applies tags to an id (which is your first argument). The id should correspond with the resource you are tagging. The id does not have to be an integer but this will usually be the case. tags must come in the form of an array (it is up to your application how this array is formed. redis-tag does not do this for you). The last argument is a callback with an argument that is the response of the set call. It will return true or false. scope is an optional argument for if you want to do something like delicious where eash user has their own set of tags. If a scope is used when tagging. you still have avaiable to you all the other methods in a non-scoped or scoped manner.

// sets tags on book 12
bookTagger.set("books", 12, ["fiction", "fantasy"], function(response){
  console.log(response) //=> true
})

OR (with scope)

// sets tags on book 12 for user 42
bookTagger.set("books", 12, ["fiction", "fantasy"], "user:42", function(response){
  console.log(response) //=> true
})

get(moduleName, id, [scope,] callback)

The get method simply takes an id and a callback with a list of tags as the response. This will always be in the form of an array.

// gets tags for book 12
bookTagger.get("books", 12, function(tags){
  console.log(tags) //=> ["fiction", "fantasy"]
})

OR (with scope)

Please note that this is only effective if you have used a scope on the set method.

// gets tags for book 12
bookTagger.get("books", 12, "user:42", function(tags){
  console.log(tags) //=> ["fiction", "fantasy"]
})

find(moduleName, tags, callback)

The find method will take an array of tags and find all the resources that have those tags in common. The callback function taken as the second argument will return with an array of ids.

// finds resources that have been tagged "fiction"
bookTagger.find("books", ["fiction"], function(ids){
  console.log(ids) //=> ["12", "27", "42", "18"]
})

OR (with scope)

Please note that this is only effective if you have used a scope on the set method.

// finds resources that have been tagged "fiction"
bookTagger.find("books", ["fiction"], "user:42", function(ids){
  console.log(ids) //=> ["12", "27", "42", "18"]
})

popular(moduleName, count, callback)

The popular will retrieve all the tags on that resource and order them from most to least most popular. It accepts an integer as its first argument describing the number of tags you want returned. The callback is called with a nested array listing the tags in decending order.

bookTagger.popular("books", 25, function(tags){
  console.log(tags) //=> [ ["fiction", 892], ["non-fiction", 423], ["fantasy", 315], ... ]
})

OR (with scope)

Please note that this is only effective if you have used a scope on the set method.

bookTagger.popular("books", 25, "user:42", function(tags){
  console.log(tags) //=> [ ["fiction", 27], ["non-fiction", 23], ["fantasy", 15], ... ]
})

License

Copyright 2011 Brock Whitten All rights reserved.

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.