MovieSearch

This is the repo that contains all the work done for the course project in IR. Be sure to follow the instructions very carefully. For an insight in the design decisions please take a look at the report.

Before you begin

Before you begin, make sure you have the following tools installed:

• Java (>= 8)
• wget (any version will do)
• Maven (Usually bundled with the Java JDK)
• Node Package Manager (npm)

Start by downloading the repo, either by a git clone or a simple download.

In order to contain the project in one location, we are going to create a folder to hold all the info. Start by creating the folder:

# Start by navigating to THIS REPO using the terminal 

# Create a dir for the project
mkdir IRProject

# Any further command will assume you are here
cd IRProject 

# Export the path for good measure, so we can use it later
export IR_PROJECT_ROOT="$(pwd)"

WARNING

All the paths assume you are working from inside of this repo. If you choose to change this, good luck!

Setup

This part will get you setup from top to bottom

Part 1: Nutch

This part will guide you in getting nutch setup for crawling the websites.

Download & partial setup

# Download Nutch
wget http://www.pirbot.com/mirrors/apache/nutch/1.15/apache-nutch-1.15-bin.tar.gz

# Unpack it
tar xvfz apache-nutch-1.15-bin.tar.gz

# Get into the main folder
cd apache-nutch-1.15/

# Create the needed folders
# urls/ will hold the urls to crawl, crawlingDir/ will hold the crawled data
mkdir -p urls/ crawlingDir/ 	

# By default, nutch requires you to tell it the websites you want to crawl. 
# Let us assume we wish to crawl `http://www.example.com/`. Then

echo "http://www.example.com/" > urls/seed.txt 

At this point, you need to set the correct regexes for how Nutch will follow the URLs. Open up the file conf/crawl-urlfilter.txt and replace the last line, the one that says

+.

with the following file

# Allow the ones on the same domain
+(example\.com)

# Refuse any other url
-.

WARNING: FOR MORE SPECIFIC REGEXES FOR MY PROJECT, CHECK THE REPORT!!!!

At this point, you are ready to crawl. Follow the instructions in the next section

Crawling

# Ensure that JAVA_HOME is set! to check, run
echo $JAVA_HOME

# If the output contains a path, you are good to go
# If the output is empty, set it by finding where you installed java. On my case, it was at
export JAVA_HOME=/Library/Java/JavaVirtualMachines/jdk-9.0.1.jdk/Contents/Home
# CHECK TO MAKE SURE THIS PATH EXISTS BEFORE YOU SET IT!

# In my case, I found that taking 20 as number of rounds yielded good results. 
# If you wish you can change this number, but I would not recommend you go under this value.
# Therefore to start crawling
./bin/crawl urls/ crawlingDir 20

The crawling process will take several hours, and in the end you will find your segments in the crawlingDir directory.

Conversion

The tool I wrote takes the content of the segments, dumped as HTML and parsed them. Therefore, before we continue, we need to convert the data from Nutch.

# Create a directory to hold the converted data
mkdir htmlDump

# Convert the content
./bin/nutch dump -segment crawlingDir/segments -outputDir htmlDump

Now you will have a folder called htmlDump that contains a lot of subfolders, each with its own document. In the next section, we use the tool I created to convert the content.

Part 2: Utility Conversion

Now we are going to create a JSON file containing only the valid articles, all bundled in one nice JSON. To do so, we use the utility that I wrote. Use Intellij and open up the project. You need to specify the following parameters in your profile as command line args:

• --imdb : Path to the IMDB Dump (Optional)
• --allmovie : Path to the AllMovie Dump (Optional)
• --out : Path to the output json, i.e. where you want the clean json to be saved

Once this process is done, we need to seed the data into Solr, and get it ready to run. This is shown in the next section

Part 3: Solr

# Start by getting back to the root of the project
cd $IR_PROJECT_ROOT

# Download Solr
wget http://mirror.easyname.ch/apache/lucene/solr/7.5.0/solr-7.5.0.tgz

# Extract it
tar xvfz solr-7.5.0.tgz

# Get into the main folder
cd solr-7.5.0/

Before we continue, we need to make sure that Solr allows cross origin requests otherwise our client won't work. Edit the file server/solr-webapp/webapp/WEB-INF/web.xml and add the following XML before the existing filter section:

<filter>
    <filter-name>cross-origin</filter-name>
    <filter-class>org.eclipse.jetty.servlets.CrossOriginFilter</filter-class>
    <init-param>
         <param-name>allowedOrigins</param-name>
         <param-value>http://localhost*</param-value>
    </init-param>
     <init-param>
         <param-name>allowedMethods</param-name>
         <param-value>GET,POST,DELETE,PUT,HEAD,OPTIONS</param-value>
     </init-param>
     <init-param>
         <param-name>allowedHeaders</param-name>
         <param-value>origin, content-type, cache-control, accept, options, authorization, x-requested-with</param-value>
     </init-param>
    <init-param>
        <param-name>supportsCredentials</param-name>
        <param-value>true</param-value>
    </init-param>
    <init-param>
      <param-name>chainPreflight</param-name>
      <param-value>false</param-value>
    </init-param>
</filter>

<filter-mapping>
  <filter-name>cross-origin</filter-name>
  <url-pattern>/*</url-pattern>
</filter-mapping>

Now, we can get solr working and ingesting data

# Start it up
./bin/solr start

# Create a new core
./bin/solr create_core -c nutch -d _default

# Seed the data from the JSON
./bin/post -c nutch $IR_PROJECT_ROOT/dump.json

At this point, you are good to go.

Running the Client

I used Vue.js, so you need NPM to get started. Then

# Get into the frontend folder
cd $IR_PROJECT_ROOT/../Frontend

# Run the server!
npm run dev

Open http://localhost:8080 and you should be good to go. Good luck!