# Introduction

This repository contains the code for the OpeNER polarity tagger. This tool tags
words in a KAF file with polarity information, which basically is:

* Polarity information, which represents positive or negative facts in a certain
  domain. Good, cheap and clean can be positive words in a hotel domain, while
  bad, expensive and dirty could be negative ones.
* Sentiment modifiers, which modify the polarity of a surrounding polarity word.
  For instance very or no are sentiment modifiers

The polarity tagger supports the following languages:

* Dutch
* German
* English
* French
* Italian
* Spanish

## How-To

The main script of this tool is a python file, which accepts a set of parameters
to determine which features or options we want to use. The language is read from
the KAF file, so it doesn't need to be specified as a parameter The program
reads a KAF file from the standard input and writes the resulting KAf in the
standard output.  To see the options you can call to the main script with the -h
or `--help` option.

    $ python core/poltagger-basic-multi.py -h
    usage: poltagger-basic-multi.py [-h] [--no-time] [--ignore-pos]
                                    [--show-lexicons {nl,en,de,es,it,fr}]
                                    [--lexicon LEXICON] [--silent] [--version]

    Tags a text with polarities at lemma level

    optional arguments:
      -h, --help            show this help message and exit
      --no-time             For not including timestamp in header
      --ignore-pos          Ignore the pos labels
      --show-lexicons {nl,en,de,es,it,fr}
                            Show lexicons for the given language and exit
      --lexicon LEXICON     Lexicon identifier, check with --show-lexicons LANG
                            for options
      --lexicon-path LEXICON The path of the lexicons
      --silent              Turn off debug info
      --version             show program's version number and exit

The `--ignore-pos` parameter must be used when want to ignore the part-of-speech
information assigned to the lemmas, and we want to assign polarities just to the
lemmas, not considering the POS tag. This could be useful when the information
provided by the pos-tagger is not accurate or the pos-tagging has not been
processed.

The main options are those concerning with the usage of different lexicons. The
lexicons are provided by the VU-sentiment-lexicon library
(https://github.com/opener-project/VU-sentiment-lexicon), which needs to be
installed.  You can see what the lexicons available for a given language are by
calling to the program with the option --show-lexicons LANG, for instance:

    core/poltagger-basic-multi.py --show-lexicons nl

    ##############################
    Available lexicons for nl
      Identifier: "hotel" (Default)
        Desc: Hotel domain lexicon for Dutch
         Res: VUA_olery_lexicon_nl_lmf
        File: /Users/ruben/python_envs/python2.7/lib/python2.7/VUSentimentLexicon/NL-lexicon/Sentiment-Dutch-HotelDomain.xml

      Identifier:"general"
        Desc: General lexicon for Dutch
         Res: VUA_olery_lexicon_nl_lmf
        File: /Users/ruben/python_envs/python2.7/lib/python2.7/VUSentimentLexicon/NL-lexicon/Sentiment-Dutch-general.xml

    ##############################

Then you can use the lexicon identifiers to select the proper lexicon, with the
option --lexicon

    cat my_input.nl.kaf | core/poltagger-basic-multi.py --lexicon general

This command will call to the polarity tagger using the general lexicon for
Dutch. The lexicon identifiers are unique only per language.  If the lexicon id
is not specified(you skip the --lexicon option), or you provide a wrong
identifier, the default lexicon will be loaded.  If there is no lexicon marked
as default in the --show-lexicon options, the first one in the list will be
used. Check the VU-sentiment-lexicon for further information about how to manage
lexicons and add new ones.

### Confused by some terminology?

This software is part of a larger collection of natural language processing
tools known as "the OpeNER project". You can find more information about the
project at [the OpeNER portal](http://opener-project.github.io). There you can
also find references to terms like KAF (an XML standard to represent linguistic
annotations in texts), component, cores, scenario's and pipelines.

Quick Use Example
-----------------

Installing the polarity-tagger can be done by executing:

    gem install opener-polarity-tagger

The polarity tagger uses python. So it is advised to run a virtualenv before
installing the gem.

Please bare in mind that all components in OpeNER take KAF as an input and
output KAF by default.

### Command line interface

You should now be able to call the polarity tagger as a regular shell command:
by its name. Once installed the gem normally sits in your path so you can call
it directly from anywhere.

This aplication reads a text from standard input in order process it.

    cat some_kind_of_kaf_file.kaf | polarity-tagger

This will output:

    <term lemma="donner" morphofeat="VP3s" pos="V" tid="t119" type="open">
      <span>
        <!--donne-->
        <target id="w119"/>
      </span>
      <sentiment polarity="neutral" resource="General domain lexicon for French . Vicomtech_general_lexicon_french"/>
    </term>

## Requirements

* Python 2.7.0 or newer
* Ruby 1.9.2 or newer
* pip
* libxml2

### Webservices

You can launch a webservice by executing:

    polarity-tagger-server

This will launch a mini webserver with the webservice. It defaults to port 9292,
so you can access it at <http://localhost:9292>.

To launch it on a different port provide the `-p [port-number]` option like this:

    polarity-tagger-server -p 1234

It then launches at <http://localhost:1234>

Documentation on the Webservice is provided by surfing to the urls provided
above. For more information on how to launch a webservice run the command with
the `--help` option.

### Daemon

Last but not least the polarity tagger comes shipped with a daemon that can read
jobs (and write) jobs to and from Amazon SQS queues. For more information type:

    polarity-tagger-daemon -h

Description of dependencies
---------------------------

This component runs best if you run it in an environment suited for OpeNER
components. You can find an installation guide and helper tools in the
[OpeNER installer](https://github.com/opener-project/opener-installer) and an
[installation guide on the Opener Website](http://opener-project.github.io/getting-started/how-to/local-installation.html)

At least you need the following system setup:

### Depenencies for normal use:

* Ruby 1.9.3 or newer
* Python 2.6 or newer
* Lxml installed

Domain Adaption
---------------

  TODO

Language Extension
------------------

  TODO

The Core
--------

The component is a wrapper around the actual language technology core. You
can find the core technolies in the `core/` folder.

Where to go from here
---------------------

* [Check the project website](http://opener-project.github.io)
* [Checkout the webservice](http://opener.olery.com/polarity-tagger)

Report problem/Get help
-----------------------

If you encounter problems, please email <support@opener-project.eu> or leave an
issue in the
[issue tracker](https://github.com/opener-project/polarity-tagger/issues).

Contributing
------------

1. Fork it <http://github.com/opener-project/polarity-tagger/fork>
2. Create your feature branch (`git checkout -b my-new-feature`)
3. Commit your changes (`git commit -am 'Add some feature'`)
4. Push to the branch (`git push origin my-new-feature`)
5. Create new Pull Request