Current File : //www/varak.net/wiki.varak.net/tests/phpunit/includes/api/RandomImageGenerator.php
<?php
/**
* RandomImageGenerator -- does what it says on the tin.
* Requires Imagick, the ImageMagick library for PHP, or the command line
* equivalent (usually 'convert').
*
* Because MediaWiki tests the uniqueness of media upload content, and
* filenames, it is sometimes useful to generate files that are guaranteed (or
* at least very likely) to be unique in both those ways. This generates a
* number of filenames with random names and random content (colored triangles).
*
* It is also useful to have fresh content because our tests currently run in a
* "destructive" mode, and don't create a fresh new wiki for each test run.
* Consequently, if we just had a few static files we kept re-uploading, we'd
* get lots of warnings about matching content or filenames, and even if we
* deleted those files, we'd get warnings about archived files.
*
* This can also be used with a cronjob to generate random files all the time.
* I use it to have a constant, never ending supply when I'm testing
* interactively.
*
* @file
* @author Neil Kandalgaonkar <neilk@wikimedia.org>
*/
/**
* RandomImageGenerator: does what it says on the tin.
* Can fetch a random image, or also write a number of them to disk with random filenames.
*/
class RandomImageGenerator {
private $dictionaryFile;
private $minWidth = 400;
private $maxWidth = 800;
private $minHeight = 400;
private $maxHeight = 800;
private $shapesToDraw = 5;
/**
* Orientations: 0th row, 0th column, Exif orientation code, rotation 2x2
* matrix that is opposite of orientation. N.b. we do not handle the
* 'flipped' orientations, which is why there is no entry for 2, 4, 5, or 7.
* Those seem to be rare in real images anyway (we also would need a
* non-symmetric shape for the images to test those, like a letter F).
*/
private static $orientations = [
[
'0thRow' => 'top',
'0thCol' => 'left',
'exifCode' => 1,
'counterRotation' => [ [ 1, 0 ], [ 0, 1 ] ]
],
[
'0thRow' => 'bottom',
'0thCol' => 'right',
'exifCode' => 3,
'counterRotation' => [ [ -1, 0 ], [ 0, -1 ] ]
],
[
'0thRow' => 'right',
'0thCol' => 'top',
'exifCode' => 6,
'counterRotation' => [ [ 0, 1 ], [ 1, 0 ] ]
],
[
'0thRow' => 'left',
'0thCol' => 'bottom',
'exifCode' => 8,
'counterRotation' => [ [ 0, -1 ], [ -1, 0 ] ]
]
];
public function __construct( $options = [] ) {
foreach ( [ 'dictionaryFile', 'minWidth', 'minHeight',
'maxWidth', 'maxHeight', 'shapesToDraw' ] as $property
) {
if ( isset( $options[$property] ) ) {
$this->$property = $options[$property];
}
}
// find the dictionary file, to generate random names
if ( !isset( $this->dictionaryFile ) ) {
foreach (
[
'/usr/share/dict/words',
'/usr/dict/words',
__DIR__ . '/words.txt'
] as $dictionaryFile
) {
if ( is_file( $dictionaryFile ) && is_readable( $dictionaryFile ) ) {
$this->dictionaryFile = $dictionaryFile;
break;
}
}
}
if ( !isset( $this->dictionaryFile ) ) {
throw new Exception( "RandomImageGenerator: dictionary file not "
. "found or not specified properly" );
}
}
/**
* Writes random images with random filenames to disk in the directory you
* specify, or current working directory.
*
* @param int $number Number of filenames to write
* @param string $format Optional, must be understood by ImageMagick, such as 'jpg' or 'gif'
* @param string|null $dir Directory, optional (will default to current working directory)
* @return array Filenames we just wrote
*/
function writeImages( $number, $format = 'jpg', $dir = null ) {
$filenames = $this->getRandomFilenames( $number, $format, $dir );
$imageWriteMethod = $this->getImageWriteMethod( $format );
foreach ( $filenames as $filename ) {
$this->{$imageWriteMethod}( $this->getImageSpec(), $format, $filename );
}
return $filenames;
}
/**
* Figure out how we write images. This is a factor of both format and the local system
*
* @param string $format (a typical extension like 'svg', 'jpg', etc.)
*
* @throws Exception
* @return string
*/
function getImageWriteMethod( $format ) {
global $wgUseImageMagick, $wgImageMagickConvertCommand;
if ( $format === 'svg' ) {
return 'writeSvg';
} else {
// figure out how to write images
global $wgExiv2Command;
if ( class_exists( 'Imagick' ) && $wgExiv2Command && is_executable( $wgExiv2Command ) ) {
return 'writeImageWithApi';
} elseif ( $wgUseImageMagick
&& $wgImageMagickConvertCommand
&& is_executable( $wgImageMagickConvertCommand )
) {
return 'writeImageWithCommandLine';
}
}
throw new Exception( "RandomImageGenerator: could not find a suitable "
. "method to write images in '$format' format" );
}
/**
* Return a number of randomly-generated filenames
* Each filename uses two words randomly drawn from the dictionary, like elephantine_spatula.jpg
*
* @param int $number Number of filenames to generate
* @param string $extension Optional, defaults to 'jpg'
* @param string $dir Optional, defaults to current working directory
* @return array Array of filenames
*/
private function getRandomFilenames( $number, $extension = 'jpg', $dir = null ) {
if ( is_null( $dir ) ) {
$dir = getcwd();
}
$filenames = [];
foreach ( $this->getRandomWordPairs( $number ) as $pair ) {
$basename = $pair[0] . '_' . $pair[1];
if ( !is_null( $extension ) ) {
$basename .= '.' . $extension;
}
$basename = preg_replace( '/\s+/', '', $basename );
$filenames[] = "$dir/$basename";
}
return $filenames;
}
/**
* Generate data representing an image of random size (within limits),
* consisting of randomly colored and sized upward pointing triangles
* against a random background color. (This data is used in the
* writeImage* methods).
*
* @return mixed
*/
public function getImageSpec() {
$spec = [];
$spec['width'] = mt_rand( $this->minWidth, $this->maxWidth );
$spec['height'] = mt_rand( $this->minHeight, $this->maxHeight );
$spec['fill'] = $this->getRandomColor();
$diagonalLength = sqrt( $spec['width'] ** 2 + $spec['height'] ** 2 );
$draws = [];
for ( $i = 0; $i <= $this->shapesToDraw; $i++ ) {
$radius = mt_rand( 0, $diagonalLength / 4 );
if ( $radius == 0 ) {
continue;
}
$originX = mt_rand( -1 * $radius, $spec['width'] + $radius );
$originY = mt_rand( -1 * $radius, $spec['height'] + $radius );
$angle = mt_rand( 0, ( 3.141592 / 2 ) * $radius ) / $radius;
$legDeltaX = round( $radius * sin( $angle ) );
$legDeltaY = round( $radius * cos( $angle ) );
$draw = [];
$draw['fill'] = $this->getRandomColor();
$draw['shape'] = [
[ 'x' => $originX, 'y' => $originY - $radius ],
[ 'x' => $originX + $legDeltaX, 'y' => $originY + $legDeltaY ],
[ 'x' => $originX - $legDeltaX, 'y' => $originY + $legDeltaY ],
[ 'x' => $originX, 'y' => $originY - $radius ]
];
$draws[] = $draw;
}
$spec['draws'] = $draws;
return $spec;
}
/**
* Given [ [ 'x' => 10, 'y' => 20 ], [ 'x' => 30, y=> 5 ] ]
* returns "10,20 30,5"
* Useful for SVG and imagemagick command line arguments
* @param array $shape Array of arrays, each array containing x & y keys mapped to numeric values
* @return string
*/
static function shapePointsToString( $shape ) {
$points = [];
foreach ( $shape as $point ) {
$points[] = $point['x'] . ',' . $point['y'];
}
return implode( " ", $points );
}
/**
* Based on image specification, write a very simple SVG file to disk.
* Ignores the background spec because transparency is cool. :)
*
* @param array $spec Spec describing background and shapes to draw
* @param string $format File format to write (which is obviously always svg here)
* @param string $filename Filename to write to
*
* @throws Exception
*/
public function writeSvg( $spec, $format, $filename ) {
$svg = new SimpleXmlElement( '<svg/>' );
$svg->addAttribute( 'xmlns', 'http://www.w3.org/2000/svg' );
$svg->addAttribute( 'version', '1.1' );
$svg->addAttribute( 'width', $spec['width'] );
$svg->addAttribute( 'height', $spec['height'] );
$g = $svg->addChild( 'g' );
foreach ( $spec['draws'] as $drawSpec ) {
$shape = $g->addChild( 'polygon' );
$shape->addAttribute( 'fill', $drawSpec['fill'] );
$shape->addAttribute( 'points', self::shapePointsToString( $drawSpec['shape'] ) );
}
$fh = fopen( $filename, 'w' );
if ( !$fh ) {
throw new Exception( "couldn't open $filename for writing" );
}
fwrite( $fh, $svg->asXML() );
if ( !fclose( $fh ) ) {
throw new Exception( "couldn't close $filename" );
}
}
/**
* Based on an image specification, write such an image to disk, using Imagick PHP extension
* @param array $spec Spec describing background and circles to draw
* @param string $format File format to write
* @param string $filename Filename to write to
*/
public function writeImageWithApi( $spec, $format, $filename ) {
// this is a hack because I can't get setImageOrientation() to work. See below.
global $wgExiv2Command;
$image = new Imagick();
/**
* If the format is 'jpg', will also add a random orientation -- the
* image will be drawn rotated with triangle points facing in some
* direction (0, 90, 180 or 270 degrees) and a countering rotation
* should turn the triangle points upward again.
*/
$orientation = self::$orientations[0]; // default is normal orientation
if ( $format == 'jpg' ) {
$orientation = self::$orientations[array_rand( self::$orientations )];
$spec = self::rotateImageSpec( $spec, $orientation['counterRotation'] );
}
$image->newImage( $spec['width'], $spec['height'], new ImagickPixel( $spec['fill'] ) );
foreach ( $spec['draws'] as $drawSpec ) {
$draw = new ImagickDraw();
$draw->setFillColor( $drawSpec['fill'] );
$draw->polygon( $drawSpec['shape'] );
$image->drawImage( $draw );
}
$image->setImageFormat( $format );
// this doesn't work, even though it's documented to do so...
// $image->setImageOrientation( $orientation['exifCode'] );
$image->writeImage( $filename );
// because the above setImageOrientation call doesn't work... nor can I
// get an external imagemagick binary to do this either... Hacking this
// for now (only works if you have exiv2 installed, a program to read
// and manipulate exif).
if ( $wgExiv2Command ) {
$cmd = wfEscapeShellArg( $wgExiv2Command )
. " -M "
. wfEscapeShellArg( "set Exif.Image.Orientation " . $orientation['exifCode'] )
. " "
. wfEscapeShellArg( $filename );
$retval = 0;
$err = wfShellExec( $cmd, $retval );
if ( $retval !== 0 ) {
print "Error with $cmd: $retval, $err\n";
}
}
}
/**
* Given an image specification, produce rotated version
* This is used when simulating a rotated image capture with Exif orientation
* @param array $spec Returned by getImageSpec
* @param array $matrix 2x2 transformation matrix
* @return array Transformed Spec
*/
private static function rotateImageSpec( &$spec, $matrix ) {
$tSpec = [];
$dims = self::matrixMultiply2x2( $matrix, $spec['width'], $spec['height'] );
$correctionX = 0;
$correctionY = 0;
if ( $dims['x'] < 0 ) {
$correctionX = abs( $dims['x'] );
}
if ( $dims['y'] < 0 ) {
$correctionY = abs( $dims['y'] );
}
$tSpec['width'] = abs( $dims['x'] );
$tSpec['height'] = abs( $dims['y'] );
$tSpec['fill'] = $spec['fill'];
$tSpec['draws'] = [];
foreach ( $spec['draws'] as $draw ) {
$tDraw = [
'fill' => $draw['fill'],
'shape' => []
];
foreach ( $draw['shape'] as $point ) {
$tPoint = self::matrixMultiply2x2( $matrix, $point['x'], $point['y'] );
$tPoint['x'] += $correctionX;
$tPoint['y'] += $correctionY;
$tDraw['shape'][] = $tPoint;
}
$tSpec['draws'][] = $tDraw;
}
return $tSpec;
}
/**
* Given a matrix and a pair of images, return new position
* @param array $matrix 2x2 rotation matrix
* @param int $x The x-coordinate number
* @param int $y The y-coordinate number
* @return array Transformed with properties x, y
*/
private static function matrixMultiply2x2( $matrix, $x, $y ) {
return [
'x' => $x * $matrix[0][0] + $y * $matrix[0][1],
'y' => $x * $matrix[1][0] + $y * $matrix[1][1]
];
}
/**
* Based on an image specification, write such an image to disk, using the
* command line ImageMagick program ('convert').
*
* Sample command line:
* $ convert -size 100x60 xc:rgb(90,87,45) \
* -draw 'fill rgb(12,34,56) polygon 41,39 44,57 50,57 41,39' \
* -draw 'fill rgb(99,123,231) circle 59,39 56,57' \
* -draw 'fill rgb(240,12,32) circle 50,21 50,3' filename.png
*
* @param array $spec Spec describing background and shapes to draw
* @param string $format File format to write (unused by this method but
* kept so it has the same signature as writeImageWithApi).
* @param string $filename Filename to write to
*
* @return bool
*/
public function writeImageWithCommandLine( $spec, $format, $filename ) {
global $wgImageMagickConvertCommand;
$args = [];
$args[] = "-size " . wfEscapeShellArg( $spec['width'] . 'x' . $spec['height'] );
$args[] = wfEscapeShellArg( "xc:" . $spec['fill'] );
foreach ( $spec['draws'] as $draw ) {
$fill = $draw['fill'];
$polygon = self::shapePointsToString( $draw['shape'] );
$drawCommand = "fill $fill polygon $polygon";
$args[] = '-draw ' . wfEscapeShellArg( $drawCommand );
}
$args[] = wfEscapeShellArg( $filename );
$command = wfEscapeShellArg( $wgImageMagickConvertCommand ) . " " . implode( " ", $args );
$retval = null;
wfShellExec( $command, $retval );
return ( $retval === 0 );
}
/**
* Generate a string of random colors for ImageMagick or SVG, like "rgb(12, 37, 98)"
*
* @return string
*/
public function getRandomColor() {
$components = [];
for ( $i = 0; $i <= 2; $i++ ) {
$components[] = mt_rand( 0, 255 );
}
return 'rgb(' . implode( ', ', $components ) . ')';
}
/**
* Get an array of random pairs of random words, like
* [ [ 'foo', 'bar' ], [ 'quux', 'baz' ] ];
*
* @param int $number Number of pairs
* @return array Two-element arrays
*/
private function getRandomWordPairs( $number ) {
$lines = $this->getRandomLines( $number * 2 );
// construct pairs of words
$pairs = [];
$count = count( $lines );
for ( $i = 0; $i < $count; $i += 2 ) {
$pairs[] = [ $lines[$i], $lines[$i + 1] ];
}
return $pairs;
}
/**
* Return N random lines from a file
*
* Will throw exception if the file could not be read or if it had fewer lines than requested.
*
* @param int $number_desired Number of lines desired
*
* @throws Exception
* @return array Array of exactly n elements, drawn randomly from lines the file
*/
private function getRandomLines( $number_desired ) {
$filepath = $this->dictionaryFile;
// initialize array of lines
$lines = [];
for ( $i = 0; $i < $number_desired; $i++ ) {
$lines[] = null;
}
/*
* This algorithm obtains N random lines from a file in one single pass.
* It does this by replacing elements of a fixed-size array of lines,
* less and less frequently as it reads the file.
*/
$fh = fopen( $filepath, "r" );
if ( !$fh ) {
throw new Exception( "couldn't open $filepath" );
}
$line_number = 0;
$max_index = $number_desired - 1;
while ( !feof( $fh ) ) {
$line = fgets( $fh );
if ( $line !== false ) {
$line_number++;
$line = trim( $line );
if ( mt_rand( 0, $line_number ) <= $max_index ) {
$lines[mt_rand( 0, $max_index )] = $line;
}
}
}
fclose( $fh );
if ( $line_number < $number_desired ) {
throw new Exception( "not enough lines in $filepath" );
}
return $lines;
}
}
Mini Shell