Re: [PHP] Saving a BLOB image to a file (SOLVED)
On 2/16/06, tedd [EMAIL PROTECTED] wrote:
However, after given it some thought, I would imagine that one could
get a unique generated string, create a file with that string, give
the file the correct permissions, then pull the image from the dB and
save, do image processing, and then reload the image into a web page,
and delete the file without any conflict. I can envision lot's of
users doing that simultaneously without problems. BUT, I haven't
tried it yet!
I have used a user's IP address (dots removed) and microtime appended
to create a unique file name. The target directory is world writable.
Not the most elegant solution... I found that sometimes the file had
not been written yet and trying to display it on a page right away
resulted in file not found...
--
Gerry
Gerry:
Above, I said that I haven't tried it yet, but I just finished the
code and it works well enough, I think. The technique is pretty
simple -- just create a tmp directory with 777 permissions and then
run this code.
?php
$token = md5(uniqid(1));
$token .= .txt;
$filename = tmp/$token;
$contents = This is the content of the file.;
echo(hrbr/Writing file br/br/);
$file = fopen( $filename, w );
fwrite( $file, $contents);
fclose( $file );
if( file_exists( $filename ) )
{
$file_length = filesize( $filename );
echo(File created at $filenamebr/ );
echo( File size: $file_length bytesbr/);
echo( br/$contentsbr/ );
}
else
{
echo( br/Unable to create filebr/ );
}
echo(hrbr/Reading file:br/br/);
$filesize = filesize($filename);
$file = fopen( $filename, r );
$text = fread( $file, $filesize );
fclose( $file );
echo( File read at: $filenamebr/ );
echo( File Size: $filesize bytesbr/ );
echo( br/$textbr/ );
echo(hrbr/Deleting file br/);
$return = unlink($filename);
if($return)
{
echo(br/Successful delete of: $filenamebr/);
}
else
{
echo(br/Failed to delete of: $filenamebr/);
}
?
--
http://sperling.com/
--
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Re: [PHP] Saving a BLOB image to a file (SOLVED)
On 2/16/06, tedd [EMAIL PROTECTED] wrote: However, after given it some thought, I would imagine that one could get a unique generated string, create a file with that string, give the file the correct permissions, then pull the image from the dB and save, do image processing, and then reload the image into a web page, and delete the file without any conflict. I can envision lot's of users doing that simultaneously without problems. BUT, I haven't tried it yet! I have used a user's IP address (dots removed) and microtime appended to create a unique file name. The target directory is world writable. Not the most elegant solution... I found that sometimes the file had not been written yet and trying to display it on a page right away resulted in file not found... Rendering the image to the screen without saving to a file works best for me. -- Gerry http://portal.danen.org/ -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Saving a BLOB image to a file (SOLVED)
What if several users try to access a different picture at the same time? Won't that render the wrong image for some? Gerry On 2/16/06, tedd [EMAIL PROTECTED] wrote: Hi gang: In a previous post (i.e., [PHP] Strange response to MySQL query) I was trying to save a BLOB as a file, namely using an INTO DUMPFILE query. If you are the system admin, and have all the system permissions, then this is not a big problem. However, if you aren't, then getting MySQL to dump a file becomes very problematic with respect to getting the right permissions to accomplish the task. So, I found a way around it. I am sure that others have thought of this before me, so I'm not claiming credit and I am sure that this solution is obvious to some -- but, it's just that I searched literally hundreds of posts and spent considerable time without finding an answer. The following is the result of my tinkering. So here goes: First, on your site create a file called my_image.png Second, give it 777 permissions. Third, in your code after opening the dB, grab the image from MySQL: $dbQuery = SELECT image; $dbQuery .= FROM $your_table ; $dbQuery .= WHERE image_Id = $pageNum; $result = mysql_query($dbQuery) or die(Error: .mysql_error()); Forth, drop the image into a variable: $fileContent = @mysql_result($result, 0, image); Fifth, create an image from a string (a great function here): $original=imagecreatefromstring($fileContent); Sixth, save the image. imagepng($original, my_image.png); And Bingo, the image is now the my_image.png file. Any comments or suggestions are welcomed. tedd -- http://sperling.com/ -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php -- Gerry http://portal.danen.org/ -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Saving a BLOB image to a file (SOLVED)
Gerry wrote: What if several users try to access a different picture at the same time? Won't that render the wrong image for some? Gerry Gerry: Normally, it's not needed for civilians. This is for when YOU want to do some image stuff on your images, like to do some background processing via your code. As for users, they just want to see the image and you can pull that out of your dB or files, whichever you prefer. tedd --- On 2/16/06, tedd [EMAIL PROTECTED] wrote: Hi gang: In a previous post (i.e., [PHP] Strange response to MySQL query) I was trying to save a BLOB as a file, namely using an INTO DUMPFILE query. If you are the system admin, and have all the system permissions, then this is not a big problem. However, if you aren't, then getting MySQL to dump a file becomes very problematic with respect to getting the right permissions to accomplish the task. So, I found a way around it. I am sure that others have thought of this before me, so I'm not claiming credit and I am sure that this solution is obvious to some -- but, it's just that I searched literally hundreds of posts and spent considerable time without finding an answer. The following is the result of my tinkering. So here goes: First, on your site create a file called my_image.png Second, give it 777 permissions. Third, in your code after opening the dB, grab the image from MySQL: $dbQuery = SELECT image; $dbQuery .= FROM $your_table ; $dbQuery .= WHERE image_Id = $pageNum; $result = mysql_query($dbQuery) or die(Error: .mysql_error()); Forth, drop the image into a variable: $fileContent = @mysql_result($result, 0, image); Fifth, create an image from a string (a great function here): $original=imagecreatefromstring($fileContent); Sixth, save the image. imagepng($original, my_image.png); And Bingo, the image is now the my_image.png file. Any comments or suggestions are welcomed. tedd -- http://sperling.com/ -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php -- Gerry http://portal.danen.org/ -- http://sperling.com/ -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Saving a BLOB image to a file (SOLVED)
So single-user disclaimer would apply? Obviously, if you have numerous people accessing your dB and doing inserts and updates, then all the lock-down stuff needs to be implemented. But, my code is not for that, but rather for someone (a single programmer) who wants to pull an image from a BLOB and save it as a file. Normally, a civilian wouldn't be doing that for if they wanted to see a file, your code would simply pull the image directly from the MySQL to the web page. No need to save as a file. However, after given it some thought, I would imagine that one could get a unique generated string, create a file with that string, give the file the correct permissions, then pull the image from the dB and save, do image processing, and then reload the image into a web page, and delete the file without any conflict. I can envision lot's of users doing that simultaneously without problems. BUT, I haven't tried it yet! tedd On 2/16/06, tedd [EMAIL PROTECTED] wrote: Gerry wrote: What if several users try to access a different picture at the same time? Won't that render the wrong image for some? Gerry Gerry: Normally, it's not needed for civilians. This is for when YOU want to do some image stuff on your images, like to do some background processing via your code. As for users, they just want to see the image and you can pull that out of your dB or files, whichever you prefer. tedd --- On 2/16/06, tedd [EMAIL PROTECTED] wrote: Hi gang: In a previous post (i.e., [PHP] Strange response to MySQL query) I was trying to save a BLOB as a file, namely using an INTO DUMPFILE query. If you are the system admin, and have all the system permissions, then this is not a big problem. However, if you aren't, then getting MySQL to dump a file becomes very problematic with respect to getting the right permissions to accomplish the task. So, I found a way around it. I am sure that others have thought of this before me, so I'm not claiming credit and I am sure that this solution is obvious to some -- but, it's just that I searched literally hundreds of posts and spent considerable time without finding an answer. The following is the result of my tinkering. So here goes: First, on your site create a file called my_image.png Second, give it 777 permissions. Third, in your code after opening the dB, grab the image from MySQL: $dbQuery = SELECT image; $dbQuery .= FROM $your_table ; $dbQuery .= WHERE image_Id = $pageNum; $result = mysql_query($dbQuery) or die(Error: .mysql_error()); Forth, drop the image into a variable: $fileContent = @mysql_result($result, 0, image); Fifth, create an image from a string (a great function here): $original=imagecreatefromstring($fileContent); Sixth, save the image. imagepng($original, my_image.png); And Bingo, the image is now the my_image.png file. Any comments or suggestions are welcomed. tedd -- http://sperling.com/ -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php -- Gerry http://portal.danen.org/ -- http://sperling.com/ -- Gerry http://portal.danen.org/ -- http://sperling.com/ -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
