[Zope-DB] Displaying an image from a MySQL blob

[Bobb]

----- Original Message -----
From: "Aaron Fosdick" <aaron at hypervision.com>
To: "zope-db mailling list" <zope-db at zope.org>
Sent: Thursday, July 01, 2004 4:57 PM
Subject: [Zope-DB] Displaying an image from a MySQL blob


> Hi - I've been battling this for a couple of days, and am hoping someone
> here can help.  I want to zope to display an image out of a MySQL blob
> field.  While uploading images works, displaying them has me stumped. I
> see that a number of other people are running into this issue also.
>
> SQL method: searchImage:
>     select filetype, picture from image where
>     <dtml-sqltest pic_ID op="eq" type="int">
>
> Python Script: displayImage:
>     photo = context.searchImage(pic_ID = pic_ID)
>     container.REQUEST.RESPONSE.setHeader('Content-type', 'image/' +
> photo[0].filetype)
>     return photo[0].picture
>
Here's my python script... hacked from someone else, probably.

called with <img src="selectimage1?id=&dtml-temp;"alt="foto">
maybe that will help
bobb

# Manually iterate over whole result set, copy into list of dicts just like
dictionaries()
# except we also read all BLOBs in their entirety and put in the value, not
the
# LobLocator

result = []
lob = ['image1']
for row in context.sql_table_image1(id=id):
  lob = row['image1']
#  result.append({'image1': lob.read()})
# above was remmed
container.REQUEST.RESPONSE.setHeader('content-type', 'image/jpeg')
return lob



> Ideally, something like: <img src ="./displayImage?pic_ID=5"> would
> serve up a jpeg.
>
> I've followed Murphy's how-to for "Upload, Insert and Retrieval of
> BLOBs", but that doesn't work since the Content-Type doesn't match the
> page content - which is text containing escaped data. This is the same
> result as 'test' in the SQL method:
>     array('c', '\xff\xd8\xff......')
> This wouldn't work anyway as I understand that zope security won't allow
> you to serve non-html from a python script.
>
>
> So there are three options that I've seen and that's where I'm getting
> stuck.  From an efficiency perspective, which of the below is the best
> method and what would the code look like?
>     1. External method  - in the python script above, use:  return
> context.extMethod(photo[0].picture)
>         This calls the method and converts the array into data
>     2. External method as a brain - pass the query result and process it
> there.
>     3. Don't use the displayImage python script at all. Do everything in
> the external method, including the sql query.
>         Is there any way to just get the raw data into a string in
> non-escaped form? I imagine that would be the least costly.
>
> I've been working on the first method, but can't seem to get a result as
> anything other than text or elements of the array.
>
> Thanks for any assistance
>
> --Aaron
>
>
> _______________________________________________
> Zope-DB mailing list
> Zope-DB at zope.org
> http://mail.zope.org/mailman/listinfo/zope-db
>