Re: ADURL failing to open specific URL

[Marco Filho via Tech-talk <tech-talk at aps.anl.gov>]

Extending the discussion, we managed to make it work with curl, so I'm wondering if it would be desirable for ADURL Driver to have an "option" record that can switch from GraphicsMagick to Curl usage and so on...

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From: Marco Filho
Sent: 17 July 2024 14:53:09
To: tech-talk at aps.anl.gov
Subject: ADURL failing to open specific URL

 

Hi all

I'm using ADURL R2-3 with ADSupport R1-10 and ADGraphicsMagick. I'm trying to use it to integrate with Hikivision camera.

The module has succesfully worked with several other URL cameras here, and testing it with a few internal URLs works.
For now, my testing criteria is that if something works like:

curl -o output <TestURL>

Then it would probably work with ADURL. Indeed, this:

caput $(PREFIX)URL1 "https://myUrl"
caput $(PREFIX)Acquire 1

Works fine with a lot of cameras here. However, for this particular hikivision camera I'm getting the error:

dbpf URL1:cam1:URL1 "https://MYURL"

dbpf URL1:cam1:Acquire 1
DBF_STRING:         "Acquire"
2024/07/17 14:26:11.700 URLDriver:readImage: error reading URL="" Unable to access configuration file (delegates.mgk) reported by ../supportApp/GraphicsMagickSrc/magick/blob.c:1971 (GetConfigureBlob)

Curiously, I tried it with a different url which I got from any image in google images:

curl -o output https://tmssl.akamaized.net/images/foto/galerie/neymar-brazil-2023-1694521247-116480.jpg

gets me a nice image of Neymar. However:

ics-ups-ioc-dev-344581 > dbpf $(PREFIX)cam1:Acquire 1
DBF_STRING:         "Acquire"
ics-ups-ioc-dev-344581 > 2024/07/17 14:29:57.383 URLDriver:readImage: error reading URL="" Unable to open file (//tmssl.akamaized.net/images/foto/galerie/neymar-brazil-2023-1694521247-116480.jpg) reported by ../supportApp/GraphicsMagickSrc/magick/constitute.c:1540 (ReadImage)

No smiling neymar for my EPICS viewer :(
Am I doing something wrong?

What I was able to find out until now:

Inside the driver, the line that generates the exception is URLDriver.cpp:82 image.read(URLString) because it immediately gets out of the try loop and catches an exception.
It calls Image::read(), which calls Image *ReadImage in constitute.c:1449

> From now on I can't quite understand what is happening... I know the condition in

if ((*image_info->filename == '@') && (!IsAccessibleNoLogging(image_info->filename)))

return(ReadImages(image_info,exception));

Is not evaluating to True but I don't think it should anyway... I still didn't find anything that seems like the method that should actually read the image from the URL.


Thanks for any insights.