Hack 48. Build a Custom Date Range Search Form

Search only Google pages indexed today, yesterday, the last 7 days, or last 30 days.

Google has a date-based search [Hack #16] but uses Julian dates. Most people can't convert Gregorian to Julian in their heads. But with a conversion formula and a little Perl scripting, you can have a Google search form that offers to let users search Google pages indexed today, yesterday, the last 7 days, or the last 30 days.

2.30.1. The Form

The frontend to the script is a simple HTML form:

<form action="http://path/to/cgi-bin/goofresh.cgi" 

method="get">

Search for:<br />

<input type="text" name="query" size="30" />

<p />

Search for pages indexed how many days back?<br />

<select name="days_back">

<option value="0">Today</option>

<option value="1">Yesterday</option>

<option value="7">Last 7 Days</option>

<option value="30">Last 30 Days</option>

</select> 

<p />

<input type="submit" value="Search">

</form>

The form prompts for two user inputs. The first is a Google query, complete with support for special syntax ["Special Syntax" in Chapter 1] and syntax mixing ["Mixing Syntaxes" in Chapter 1]; after all, we'll just be passing your query along to Google itself. The second input, a pull-down list, prompts for how many days' worth of search the form should perform.

2.30.2. The Code

Note that this script just does a couple of date translations in Perl and redirects the browser to Google, altered query in tow. It's just a regular query as far as Google is concerned, so it doesn't require a developer's API key.

This hack requires an additional module, Time::JulianDay, and won't run without it (http://search.cpan.org/search?query=Time%3A%3AJulianDay).

#!/usr/local/bin/perl

# goofresh.cgi

# Searches for recently indexed files on Google.

# Usage: goofresh.cgi is called as a CGI with form input,

# redirecting the browser to Google, altered query in tow.

     

use CGI qw/:standard/;

use Time::JulianDay;

     

# Build a URL-escaped query.

(my $query = param('query')) =~ s#(\W)#sprintf("%%%02x", ord($1))#ge;

     

# How many days back?

my $days_back = int param('days_back') || 0;

     

# What's the current Julian date?

my $julian_date = int local_julian_day(time);

     

# Redirect the browser to Google with query in tow.

print redirect(

    'http://www.google.com/search?num=100' .

    "&q=$query" .

    "+daterange%3A" . ($julian_date - $days_back) . "-$julian_date"

);

2.30.3. Running the Hack

Point your browser at the location of the form you just created. Enter a query, choose how many days to go back, and click the Search button. You'll be sent on to Google with the appropriate daterange: restriction in tow.

2.30.4. Hacking the Hack

If you don't like the date ranges hardcoded into the form, make up your own and adjust the form accordingly:

<form action="http://path/to/cgi-bin /goofresh.cgi" 

method="get">

Search for:<br />

<input type="text" name="query" size="30" />

<p />

Search for pages indexed how many days back?<br />

<select name="days_back">

<option value="0">Today</option> 

<option value="30">Around 1 Month</option> 

<option value="60">Around 2 Months</option> 

<option value="90">Around 3 Months</option> 

<option value="365">1 Year</option> 

</select>

<p />

<input type="submit" value="Search">

</form>

Or simply let the user specify how many days to go back in a text field:

<form action="http://

path/to/cgi-bin

/goofresh.cgi" 

method="get">

Search for:<br />

<input type="text" name="query" size="30" />

<p />

Search for pages indexed how many days back?<br />

<input type="text" name="days_back" size="4" 

maxlength="4" />

<p />

<input type="submit" value="Search"> 

</form>