ImageTragick “fix” broke my script and not sure how to fix

问题

Using Imagick, I'm placing custom jpgs into an svg and then converting them to a jpg. Because of the ImageTragick, my placed jpegs never show up and my font doesn't convert. Because of the vulnerability my host upgraded their policy.xml and now it's broken.

<policymap>
<!-- <policy domain="system" name="precision" value="6"/> -->
<!-- <policy domain="resource" name="temporary-path" value="/tmp"/> -->
<policy domain="resource" name="memory" value="32MiB"/>
<policy domain="resource" name="map" value="32Mib"/>
<!-- <policy domain="resource" name="area" value="1GB"/> -->
<!-- <policy domain="resource" name="disk" value="16EB"/> -->
<!-- <policy domain="resource" name="file" value="768"/> -->
<policy domain="resource" name="thread" value="1"/> -->
<!-- <policy domain="resource" name="throttle" value="0"/> -->
<policy domain="resource" name="time" value="30"/>
<policy domain="coder" rights="none" pattern="EPHEMERAL" />
<policy domain="coder" rights="none" pattern="URL" />
<policy domain="coder" rights="none" pattern="HTTPS" />
<policy domain="coder" rights="none" pattern="MVG" />
<policy domain="coder" rights="none" pattern="MSL" />
</policymap>

I have no idea where to begin fixing it. I've read about confirming the image types but am confused about where that code goes.

Basically, I refer to the image I want using...

$imageURL = $_POST['imageURL'];

Then I build an svg string using...

$svgString = <<<EOD
<svg class="svgImage" viewBox="0 0 1200 630" preserveAspectRatio="xMidYMin slice">
    <image id="placedImage" xlink:href="$imageURL" x="0" y="0" height="630px" width="1200px" />
    <text class="newText topText" id="topTextWhite" style="font-size:24px; font-family: impact, sans-serif;" text-anchor="middle" x="600" y="100" fill="black">Test top words</text>
    <text class="newText bottomText" id="bottomTextWhite" style="font-size:24px; font-family: impact, sans-serif;" text-anchor="middle" x="600" y="600" fill="black">Test bottom words</text>
</svg>
EOD;

Then prep it for a run through Imagick()

//NEW FILENAME INCLUDING MICROTIME TO PREVENT DUPLICATIONS
$fileName = "name". microtime(true);
$newFileName = 'gallery/' . $fileName . '.jpg';

//THE FILE WE'LL BE WORKING WITH
$file =  'gallery/' . $fileName . '.svg';

//INITIALIZE STRING FOR PROPER SVG CONVERSION
$current = '<?xml version="1.0" encoding="UTF-8" standalone="no"?>';

//APPEND CONTENT STRING
$current .= $svgString;

//WRITE THE FILE CONTENTS INTO THE FILE
//If file already exists, it will replace it.
file_put_contents($file, $current);

//START CONVERSION PROCESS
$svg = file_get_contents($file);

$image = new Imagick();
$image->setFont("Impact.ttf");
$image->readImageBlob($svg);
$image->setCompression(Imagick::COMPRESSION_JPEG);
$image->setCompressionQuality(60);
$image->setImageFormat("jpg");
$image->writeImage($newFileName);
$image->clear();
$image->destroy();

//DESTROY SVG FILE
unlink($file);

And this worked fine for many months. Now, the conversion happens but the fonts aren't included and the placed image appears as just a white background. Any suggestions on how to get this up-and-running until we get a chance to implement a new solution? Thanks.

回答1:

A few things here.

<image id="placedImage" xlink:href="$imageURL" x="0" y="0" height="630px" width="1200px" />
                                    ^~~~~~~~^

The policy restriction on URL and/or HTTPS will must likely block this behavior.

$image->readImageBlob($svg); // <-- May throw 'not authorized' exception

The MVG restriction would block the intermediate XML-to-MVG file from being read.

So what's a possible solution?

If you can't read remote resources, or intermediate vector graphics files, then plan on collecting the image parts & building the image directly. Here's an example.

// Create a blank Canvas (YMMV)
$image = new Imagick();
$image->newPseudoImage(1200, 630, 'xc:');
// Read background image
$background = new Imagick($imageURL); // Can no longer be remote URL/HTTP(S)
// Resize to canvas
$background->resizeImage(1200, 630, Imagick::FILTER_LANCZOS, 1.0, false);
// Copy to canvas (again, YMMY)
$image->compositeImage($background, Imagick::COMPOSITE_ATOP, 0, 0, Imagick::CHANNEL_ALL);
// Create a drawing context
$ctx = new ImagickDraw();
// Read font as before
$ctx->setFont("Impact.ttf");
$ctx->setFontSize(24);
// Calculate what the font will be ...
$font_metrics = $image->queryFontMetrics($ctx, "Test top words", false);
// ... and draw it at position.
$ctx->annotation(600 - $font_metrics['textWidth'] / 2, 100, "Test top words");
// repeat as needed
$font_metrics = $image->queryFontMetrics($ctx, "Test bottom words", false);
$ctx->annotation(600 - $font_metrics['textWidth'] / 2, 600, "Test bottom words");
// Draw context
$image->drawImage($ctx);
// Write to JPG
$image->setCompression(Imagick::COMPRESSION_JPEG);
$image->setCompressionQuality(60);
$image->writeImage($newFileName);

Of course the above solution can be simplified / reduced, but should get you started.

来源：https://stackoverflow.com/questions/37686984/imagetragick-fix-broke-my-script-and-not-sure-how-to-fix

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