[RFC] Ajax Live Search

[Louis7777]

Description
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Add a dropdown results box below the quick search, to show results as the user is typing.

Justification
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Nowadays users often expect something to happen when they start typing in a search box. They may expect to see keyword suggestions or results related to the content they are interested in, because they have got used to such functionality.

I think that an Ajax Live Search should be core functionality, because most of the world's top websites have it even though they are of different nature (e.g. search engines, social networks, e-commerce websites, e-mail web services etc.). A few examples:

Google, Yahoo, Bing, Baidu, YouTube, Gmail, Outlook, Facebook, LinkedIn, GitHub, Amazon, Ebay, IMDb, Alexa, Podnapisi etc.

Also, top CMS such as Joomla and Wordpress have it. I don't know any forum software that has it yet (I've only seen it in Administration Panels)... so why not be the first?

Implementation
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I think it should look similar to Facebook's and it could display the top related topic titles. PhpBB already has the functionality to search in topic titles, posts, topic titles + posts or only in the first post of topics and display an ordered list of results.

There could be a couple of ACP options to limit the number of results and to enable/disable searching in posts (i.e. search only in titles).

If the user has JavaScript disabled, then no problem - he'll only miss this enhancement.

If there are performance concerns, then no problem - have it disabled by default and make an On/Off switch in ACP.

[valid]

How to prevent abuse? This function is quite intensive.

[nickvergessen]

We have a search flood limit?

[brunoais]

I'm cool with this but we also need to prevent flooding the server with requests when this is on. We better wait a while before trying to search. Anyway, sounds good to me, specially when searching for posts from a specific username (help typing the username) and help typing some more common words (larger than x letters) in the board.

[jsebean]

I'm gonna say -1 on this one. This is WAY too cpu intensive. 99% of boards on the net I'd be willing to bet do not have the processing power as facebook or google. I could see this getting abused. If people want this, I'd say leave it as an extension as there'd be nothing wrong with that.

[Dragosvr92]

This would be nice, as the current search system is unable to find certain keywords. Maybe it can suggest what it can be searched.
But they really should expand the search function and make that possible.

[AmigoJack]

current search system is unable to find certain keywords

Then a live search would not help either. I modified my board to at least inform the user which stopwords he encountered instead of just giving a generic failure message.

It would be more a help to make users aware of what keywords are, what operators are and what phrases are, as then they'd be able to issue a more precise search, whereas potential suggestions are no help in understanding a board search.