I'm trying to expose a search feature in rails. I want a user to be able to enter a string like name:"john" color:"blue" and get a list of ActiveRecord objects for some model that have a name attribute containing john and a color attribute containing blue. I'd also like them to be able to use and and or and parentheses e.g. name:"john" or color:"blue" or (name:"john" color:"blue") or name:"bill". Ideally they could also use things like age<20 where age is an numeric field. Is there a rails plugin that does this. I've was looking briefly at sphinx and ferret both of which seem to create an api for this but it was unclear whether they provided a clear text based option or if I would need to parse the search strings myself.
Ernie's Ransack gem is a good place to start.
You will have to provide an intermediate layer between your submitted form and the Ransack code (this would be a good idea anyway for security reasons) to convert strings from the format you desire to something Ransack can understand.
If you check the demo page and the documentation for the gem you'll find it's quite simple to create the sort of queries you're after.
Watch how GET requests are generated from the conditions you build and in your application replace the builder Ernie has in the demo with a single textfield accepting strings like (name:"john" color:"blue") or name:"bill". Do some pattern matching when this field is submitted and build a proper querystring to pass onto the Ransack gem.
Edit
For future questions like "what's a popular gem for ______?", check out The Ruby Toolbox. If Ransack doesn't suit your needs, perhaps a gem in the Rails Search category has what you're looking for. I personally use Ransack for exactly what you're describing; providing a custom query interface for my application's User model.
I'd suggest doing your own search class. I find that for each app I do, the needs of search change considerably and it's simple enough to create a search app that considers all the variables you might want in a search query, posed against any number of classes you want to search.
In your Search class, have it return a collection, in the order you desire, and the collection can be made up of object instances that the searcher may desire.
Related
I'm currently evaluating whether to use ActsAsTaggableOn or roll my own.
I can't have users create tags at random but want to define a list of allowed tags for a project model. Users associated with that project can only select the tags that are allowed for that project (through project and tag model where a project can have multiple tags).
The sane thing to do seems to use ActsAsTaggableOn, but after googling for more than one hour I can't find a lot of documentation on my use-case.
I haven't used ActsAsTaggableOn but if your only issue is retricting what tags can be selected, that should be easy.
Use a gem like chosen-rails to make a nice selector to choose tags from an array of allowed tags that you supply. The returned array of selected tags are assigned to your acts_as_taggable_on field.
If the ActsAsTaggableOn doesn't support array input (I'm not clear on that) make the array an attr_accessor field such as tag_array and then do
my_object.my_tags = tag_array.join(',')
I'm new to Ruby and to Rails. I have played a bit with Sinatra but I think that Rails is a more complete framework for my project. However, I am running into trouble with this.
I am working with an fairly substantial existing, and heavily used, mySQL database and I am trying to build an API for this that will report on certain features. The features that are needed are, for the most part, counts of records by certain groupings, then drilling down into details.
For example we have a table - tableA, that contains lots of information relating to documentation. One piece of information we want to report on from that is the number of items in a given language. The language code is stored against each item and based on a get request I would like to return JSON.
Request: /languages/:code/count/:tablename
There are two variables in that most specific URL - the code we are counting and the table we are counting from.
I understand that in routes.rb I can set up a mapping:
get '/languages/:code/count/:table', :controller=>'languages', :action=>'count'
I have a controller - languages_controller.rb with a count method in it. this then matches to a corresponding view file count.html.erb
In all the tutorials I have read and examples I have followed the main point seems that 'languages' would be a table in the database and would therefore be available under the 'magic' Rails approach.
My issue is that it is not a table, rather the results of the call should be a limited subset of the fields in tableA. Such as languagecode and count(id).
The description of the language needs to be looked up 'manually' as it is stored as an internal code that is not in a database anywhere (historic decision/madness).
The questions:
how do I have a model that is only a subset of fields, plus some that are manually populated - languagecode, isocode, description, count
Am I right in thinking that once I have the model defined as such as I could use ActiveRecord to get data from the database and then in the controller add the extra information in?
Can I change table in the model based on the parameter sent in the URL?
Essentially, I am at a loss at the moment on what to do with this. I have the routes defined, the view templates in place and the controller there and ready to go. The database component - getting some data from a pre-existing table seems mysterious to me.
Any help is greatly appreciated, it seems that the framework is currently getting in my way and I know that I can't be the only one trying this sort of thing so if you have any advice please share.
There's really no need for a model here, at all. This isn't what ORMs are for. What you should be doing is just running raw SQL against the database, and iterating over the results. Consider doing something like this: https://stackoverflow.com/a/14840547/229044
I want to create a tagging system like seen here on Stack Overflow or on Quora. It'll be its own model, and I'm planning on using this autocomplete plugin to help users find tags. I have a couple of questions:
I want tags to be entirely user-generated. If a user inputs a new tag by typing it and pressing an "Add" button, then that tag is added to the db, but if a user types in an existing tag, then it uses that one. I'm thinking of using code like this:
def create
#video.tags = find_or_create_by_name(#video.tags.name)
end
Am I on the right track?
I'd like to implement something like on Stack Overflow or Quora such that when you click a tag from the suggested list or click an "Add" button, that tag gets added right above the text field with ajax. How would I go about implementing something like that?
I know this is kind of an open-ended question. I'm not really looking for the exact code as much as a general nudge in the right direction. Of course, code examples wouldn't hurt :)
Note I am NOT asking for help on how to set up the jQuery autocomplete plugin... I know how to do that. Rather, it seems like I'll have to modify the code in the plugin so that instead of the tags being added inside the text field, they are added above the text field. I'd appreciate any direction with this.
mbleigh's acts_as_taggable_on gem is a feature-complete solution that you should definitely look into a little more closely. The implementation is rock-solid and flexible to use. However, it is mostly concerned with attaching tags to objects, retrieving tags on objects, and searching for tagged items. This is all backend server stuff.
Most of the functionality you are looking to change (based on your comments) is actually related more to your front-end UI implementation, and the gem doesn't really do much for you there. I'll take your requests one-by-one.
If user inputs a new tag, that tag
gets added, if user inputs an
existing tag, the existing tag gets
used. acts_as_taggable_on does this.
Click a tag from suggested list to
add that tag. This is an
implementation issue - on the
back-end you'll need to collect the
suggested list of tags, then display
those in your presentation as links
to your processing function.
Autocomplete as user enters
potential tag. You'll use the jQuery
autocomplete plugin against a list
of items pulled off the tags table.
With additional jQuery, you can
capture when they've selected one of
the options, or completed entering
their new tag, and then call the
processing function.
Restrict users to entering only one
tag. This will be your UI
implementation - once they've
entered or selected a tag, you
process it. If they enter two words
separated by a comma, then before or
during processing you have to either
treat it as one tag, or take only
the text up to the first comma and
discard the rest.
When you process the addition of a
tag, you will have to do two things.
First, you'll need to handle the UI
display changes to reflect that a
tag has been entered/chosen. This
includes placing the tag in the
"seleted" area, removing it from the
"available" display, updating any
counters, etc. Second, you'll need
to send a request to the server to
actually add the tag to the object
and persist that fact to the
database (where the taggable gem will take over for you). You can either do this via
an individual AJAX request per tag,
or you can handle it when you submit
the form. If the latter, you'll need
a var to keep the running list of
tags that have been added/removed
and you'll need code to handle
adding/removing values to that var.
For an example of saving tags while editing but not sending to server/db until saving a form, you might take a look at the tagging functionality on Tumblr's new post page. You can add/remove tags at will while creating the post, but none of it goes to the database until you click save.
As you can see, most of this is on you to determine and code, but has very little to do with the backend part. The gem will take care of that for you quite nicely.
I hope this helps get you moving in the right direction.
The more I try to force the acts-as-taggable-on gem to work the more I think these are fundamentally different types of problems. Specifically because of aliases. The gem considers each tag to be its own special snowflake, making it difficult to create synonyms. In some cases it doesn't go far enough, if you want the Tag to have a description you'd need to edit the given migrations (which isn't hard to do).
Here's what I'm considering implementing, given the trouble I've had implementing via the gem. Let's assume you want to create a tagging system for Technologies.
Consider the following psuedo code, I haven't yet tested it.
rails g model Tech usage_count::integer description:text icon_url:string etc. Run the migration. Note the
Now in the controller you will need to increment usage_count each time something happens, the user submits a new question tagged with given text.
rails g model Name::Tech belongs_to:Tech name:string
Name::Tech model
belongs_to :tech
end
Then you could search via something like:
search = Name::Tech.where("name LIKE :prefix", prefix: "word_start%")
.joins(:tech)
.order(usage_count: desc)
.limit(5)
This is starting point. It's fundamentally different from the gem, as each tag is just a string on its own, but references a richer data table on the back end. I'll work on implementing and come back to update with a better solution.
Let's say I want to trend all comments posted on a site and create dynamic tags. For example, If there are x number of comments that contain the word iPad I would like to create automatically create a tag called "iPad" and put it in a tag cloud.
Is this possible? I checked out the acts_as_taggable gem but it requires one to specify a tag, I guess I am looking for a way to generate tags from content.
Well something like the yahoo term extraction service might do the trick and there is a plugin for it http://expressica.com/auto_tags/.
Though it is not for commercial use.
Sure, this is possible.
Just parse the content of each comment as it's passed in and attach the tags you're interested in.
This can either work on a whitelist - where you specify all the tags you're interested in and attach those if relevant.
Or it could work on a blacklist - where you specify all the words to ignore, e.g. "the", "on". This approach is probably a lot more time consuming, but would allow for more dynamic results.
I would probably work on a white list, then have an ability to add new tags to the whitelist and have it go back and retroactively add the tags where applicable.
What's the best way to implement an interface that looks like this in rails?
Currently I'm using Searchlogic, and it's a tad painful. Problems include:
Making sure certain operations remain orthogonal -- for example, if you select "Short Posts" and then search, your search results should be restricted to short posts.
Making sure the correct link gets the "selected" class. Right now the links are <a>'s, so maintaining this state client-side is tricky. I'm hacking it by having the AJAX response to, say, sorting return a new sort links section with the correct link "selected". Using radio buttons instead of <a> tags would make it easier to maintain state client-side -- maybe I should do that?
I recently solved a similar problem using named_scopes and some ruby metaprogramming that I rolled up into a plugin called find_by_filter.
find_by_filter accepts a hash of scope
names and values, and chains them into
parametised scope calls. If the model has a named_scope that matches the provided name, this is called.If no named_scope is found, an anonymous scope is created.