Filippo Pacini

Simple script to create image thumbnails from the command line

2010-12-06T00:00:00+00:00

Simple script to create image thumbnails from the command line

Every website has one or more photo galleries, so one of the common tasks when building websites is reducing photos to put in photo galleries.

I’ve built a simple shell script that uses ImageMagick to create thumbnails and convert images to RGB. You can download the script in case you find it useful.

Usage example:

$ img_resize.sh imagesdir 650x650 x150

The script recurse into iamgesdir looking for images (.png, jpg, .gif, .tiff). It then resizes every image so it fits in a box of 650x650. The image is resized only if bigger and aspect ratio is preserved. The new images have a -B (for big) appended at the end of the name, right before the extension. The second size, which is optional, tells the script to resize the image to 150 pixels height. Aspect ratio is preserved. The new images have a -S (for small) appended at the end of the name, right before the extension.

Here is the complete script:

#/bin/bash
Usage="Usage: $0 basedir geometry1 [geometry2]"

prhelp() {
    echo "$Usage 

Recursively looks for images inside basedir and resizes them to geometry1 adding -B (for big) to the name before the extension and, optionally, resizes to geometry2 adding -S (for small) before the extension. 
Resizing always keeps aspect ratio.
If the image is already smaller then geometry the image it's not stretched. 

Geometry examples:
- 150x170 resizes the image to fit in a rectangle of width 150 pixels and height 170 pixels.
- 150     resizes image to a width of 150 pixels.
- x150    resizes image to en height of 150 pixels.
 "
}

convert_name() {
    local full_name=$1
    local small_or_big=$2
    #split name into base and extension
    local base_dir=$(dirname $full_name)
    local base_name=$(basename $full_name)
    local name=$(echo "$base_name" | cut -d'.' -f1)
    local ext=$(echo "$base_name" | cut -d'.' -f2)
    echo "$base_dir/$name$small_or_big.$ext"
}

thumb() {
    local in_file=$1
    local out_file=$2
    local geometry=$3
    $(convert -colorspace RGB -density 72x72 -strip -thumbnail $geometry\> $in_file $out_file)
}

if [ $# -le 1 ]; then
    prhelp
    exit 1
fi

#read input parameters
basedir=$1
geo_big=$2
geo_small=$3

for i in $(find $basedir -iname *.jpg -o -iname *.jpeg -o -iname *.png -o -iname *.gif -o -iname *.tiff); do
    echo "Resizing $i"
    if [ -n "$geo_small" ]; then
	small_name=$(convert_name $i '-S');
	$(thumb $i $small_name $geo_small);
    fi
    big_name=$(convert_name $i '-B');
    $(thumb $i $big_name $geo_big);
done;

How to extract a range of lines from a file

2010-12-03T00:00:00+00:00

How to extract a range of lines from a file

Yesterday one of our customers had accidentaly deleted all their products from the database.

Backup and unix filters to the rescue!

We got the most recent backup of the database and grepped to find the lines we had to restore. Then used head and tail to extract the part we needed and restored it.

Let’s see how you can extract a range of lines using head and tail. Here is the example file called ex.txt:

line number 1
line number 2
line number 3
line number 4
line number 5
line number 6
line number 7

Suppose you want to extract from line number 3 to line number 5 you can do it in 2 ways using head and tail:

head -5 ex.txt | tail -3

head -5 extracts the first 5 lines from ex.txt and passes them to ` tail -3 ` to get the last 3 lines.

Or you can do the same with:

tail -n+3 ex.txt | head -3

Here with ` tail -n+3 ` you extract lines from 3 to the end of the file and with ` head -3 ` you get the first 3 lines.

Running symfony on Nginx

2010-12-02T00:00:00+00:00

Running symfony on Nginx

A few days ago we published a website built using the symfony php framework.

We had some problems making symfony work correctly on nginx. In particular there were issues with url rewriting: everything worked well for the frontend, but in the backend links to css and images were wrong.

We made a lot of googling and a lot trial and errors. The problem seems well know, but none of the solutions found online worked for us, so I’ve decided to write down our solution for future reference and for others who might have the same problem.

What worked for us was using two different virtual servers: one for the frontend and one for the backend.

We defined a virtual server named (e.g. www.example.com) with a configuration that looks more or less like this:

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server {
  listen   80;
  server_name  www.example.com;

  access_log  /var/log/nginx/example.com.access.log;
  error_log   /var/log/nginx/example.com.error.log warn;

  root        /var/www/example.com/web;
  index       index.php;
  charset utf-8;

  location / {
    # If file exists as is static serve it directly
    if (-f $request_filename) {
      expires max; 
      break; 
    }
    if ($request_filename !~ "\.(js|ico|gif|jpg|png|css)$") {
      rewrite ^(.*) /index.php last;
    }
  }

  location ~ \.php($|/) {
    set  $script     $uri;
    set  $path_info  "";
    if ($uri ~ "^(.+\.php)($|/)") {
      set $script $1;
    }
    if ($uri ~ "^(.+\.php)(/.+)") {
      set  $script     $1;
      set  $path_info  $2;
    }

    fastcgi_pass   127.0.0.1:9000;

    include /etc/nginx/fastcgi_params;

    fastcgi_param  SCRIPT_FILENAME  /var/www/example.com/web$script;
    fastcgi_param  PATH_INFO        $path_info;
  }
}

And another one (e.g. admin.example.com) for the backend. admin.example.com looks exactly the same, except the index.php is replaced with backend.php.

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server {
  listen   80;
  server_name  admin.example.com;

  access_log  /var/log/nginx/example.com.access.log;
  error_log   /var/log/nginx/example.com.error.log warn;

  root        /var/www/example.com/web;
  index       backend.php;
  charset utf-8;

  location / {
    # If file exists as is static serve it directly
    if (-f $request_filename) {
      expires max; 
      break; 
    }
    if ($request_filename !~ "\.(js|ico|gif|jpg|png|css)$") {
      rewrite ^(.*) /backend.php last;
    }
  }

  location ~ \.php($|/) {
    set  $script     $uri;
    set  $path_info  "";
    if ($uri ~ "^(.+\.php)($|/)") {
      set $script $1;
    }
    if ($uri ~ "^(.+\.php)(/.+)") {
      set  $script     $1;
      set  $path_info  $2;
    }

    fastcgi_pass   127.0.0.1:9000;

    include /etc/nginx/fastcgi_params;

    fastcgi_param  SCRIPT_FILENAME  /var/www/example.com/web$script;
    fastcgi_param  PATH_INFO        $path_info;
  }
}

How to run php on nginx

2010-11-16T00:00:00+00:00

Intro

After a lot of time I decided to restart writing some blog posts. I moved from my home made blog platform to Jekyll. I also moved the blog to Github Pages which support Kekyll.

So far I’m really happy with the new platform.

Below is the first post: I wrote down some notes on how we configured nginx to run php as a fastcgi service.

How to run php on nginx

Some months ago we started using Rackspace cloud servers and decided to use Nginx to serve web pages. Nginx is a really fast HTTP server with easy configuration and a rich feature set.

Configuring Nginx to serve static content was really straightforward. Then we decided to add .php through fastcgi.

We used this article as a base to run a php FastCGI service and to configure Nginx to use the service for .php pages.

A nice feature in Nginx is the include directive which enables you to include any configuration file for whatever purpose you want. So we factored out the part relative to php pages in a separate file.

Something like: serve_php.conf

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fastcgi_index   index.php;

location ~ \.php {
  include /etc/nginx/fastcgi_params;
  keepalive_timeout 0;
  fastcgi_param   SCRIPT_FILENAME  $document_root$fastcgi_script_name;
  fastcgi_pass    127.0.0.1:9000;
  include        /etc/nginx/fastcgi_params;
}

Then when we want to enable php on a website we can simply include the serve_php.conf file. Below is an example.com website serving php.

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server {
  listen   80;
  server_name  example.com  www.example.com;

  access_log  /var/log/nginx/example.com.access.log;
  error_log   /var/log/nginx/example.com.error.log warn;

  root        /var/www/example.com/public;
  index       index.php index.html;

  #serve php files
  include /etc/nginx/serve_php.conf;
}