Closed ibrummel closed 11 months ago
ibrummel
commented
11 months ago I should have put this in the commit description but this is an issue that I ran into using an HP ENVY PHOTO 6255. Please let me know if I can improve the style or approach in this code. I am not very familiar with node or JS in general.
Cheers
manuc66
commented
11 months ago Hi @ibrummel thanks for submitting this pr and sorry for the regression
Could you provide the payload sample that is causing the issue so that we can try to implement the fix without relying on Exception catch control flow
ibrummel
commented
11 months ago Hi @manuc66,
Best I can tell this issue is coming up because my printer returns information that just doesn't include an ADF block in the XML. The returned XML is here:
<?xml version="1.0" encoding="UTF-8"?>
<!-- THIS DATA SUBJECT TO DISCLAIMER(S) INCLUDED WITH THE PRODUCT OF ORIGIN. -->
<ScanCaps xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.hp.com/schemas/imaging/con/cnx/scan/2008/08/19">
<DeviceCaps>
<ModelName>ENVY Photo 6200 All-in-One Printer series</ModelName>
<DerivativeNumber>0</DerivativeNumber>
</DeviceCaps>
<ColorEntries>
<ColorEntry>
<ColorType>K1</ColorType>
<Formats>
<Format>Raw</Format>
</Formats>
<ImageTransforms>
<ImageTransform>ToneMap</ImageTransform>
<ImageTransform>Sharpening</ImageTransform>
<ImageTransform>BwThreshold</ImageTransform>
</ImageTransforms>
</ColorEntry>
<ColorEntry>
<ColorType>Gray8</ColorType>
<Formats>
<Format>Raw</Format>
<Format>Jpeg</Format>
</Formats>
<ImageTransforms>
<ImageTransform>ToneMap</ImageTransform>
<ImageTransform>Sharpening</ImageTransform>
</ImageTransforms>
</ColorEntry>
<ColorEntry>
<ColorType>Color8</ColorType>
<Formats>
<Format>Raw</Format>
<Format>Jpeg</Format>
</Formats>
<ImageTransforms>
<ImageTransform>ToneMap</ImageTransform>
<ImageTransform>Sharpening</ImageTransform>
</ImageTransforms>
</ColorEntry>
</ColorEntries>
<Platen>
<InputSourceCaps>
<MinWidth>8</MinWidth>
<MinHeight>8</MinHeight>
<MaxWidth>2550</MaxWidth>
<MaxHeight>3508</MaxHeight>
<RiskyLeftMargin>34</RiskyLeftMargin>
<RiskyRightMargin>34</RiskyRightMargin>
<RiskyTopMargin>42</RiskyTopMargin>
<RiskyBottomMargin>45</RiskyBottomMargin>
<MinResolution>75</MinResolution>
<MaxOpticalXResolution>1200</MaxOpticalXResolution>
<MaxOpticalYResolution>1200</MaxOpticalYResolution>
<SupportedResolutions>
<Resolution>
<XResolution>75</XResolution>
<YResolution>75</YResolution>
<NumCcd>1</NumCcd>
<ColorTypes>
<ColorType>K1</ColorType>
<ColorType>Gray8</ColorType>
<ColorType>Color8</ColorType>
</ColorTypes>
</Resolution>
<Resolution>
<XResolution>100</XResolution>
<YResolution>100</YResolution>
<NumCcd>1</NumCcd>
<ColorTypes>
<ColorType>K1</ColorType>
<ColorType>Gray8</ColorType>
<ColorType>Color8</ColorType>
</ColorTypes>
</Resolution>
<Resolution>
<XResolution>150</XResolution>
<YResolution>150</YResolution>
<NumCcd>1</NumCcd>
<ColorTypes>
<ColorType>K1</ColorType>
<ColorType>Gray8</ColorType>
<ColorType>Color8</ColorType>
</ColorTypes>
</Resolution>
<Resolution>
<XResolution>200</XResolution>
<YResolution>200</YResolution>
<NumCcd>1</NumCcd>
<ColorTypes>
<ColorType>K1</ColorType>
<ColorType>Gray8</ColorType>
<ColorType>Color8</ColorType>
</ColorTypes>
</Resolution>
<Resolution>
<XResolution>300</XResolution>
<YResolution>300</YResolution>
<NumCcd>1</NumCcd>
<ColorTypes>
<ColorType>K1</ColorType>
<ColorType>Gray8</ColorType>
<ColorType>Color8</ColorType>
</ColorTypes>
</Resolution>
<Resolution>
<XResolution>400</XResolution>
<YResolution>400</YResolution>
<NumCcd>1</NumCcd>
<ColorTypes>
<ColorType>K1</ColorType>
<ColorType>Gray8</ColorType>
<ColorType>Color8</ColorType>
</ColorTypes>
</Resolution>
<Resolution>
<XResolution>600</XResolution>
<YResolution>600</YResolution>
<NumCcd>1</NumCcd>
<ColorTypes>
<ColorType>K1</ColorType>
<ColorType>Gray8</ColorType>
<ColorType>Color8</ColorType>
</ColorTypes>
</Resolution>
<Resolution>
<XResolution>1200</XResolution>
<YResolution>1200</YResolution>
<NumCcd>1</NumCcd>
<ColorTypes>
<ColorType>K1</ColorType>
<ColorType>Gray8</ColorType>
<ColorType>Color8</ColorType>
</ColorTypes>
</Resolution>
</SupportedResolutions>
</InputSourceCaps>
</Platen>
</ScanCaps>The parsed version before createScanCaps returns to the constructor looks like this, without an ADF block:
{
ScanCaps: {
'$': {
\'xmlns:xsi\': 'http://www.w3.org/2001/XMLSchema-instance',
xmlns: 'http://www.hp.com/schemas/imaging/con/cnx/scan/2008/08/19'
},
DeviceCaps: [ [Object] ],
ColorEntries: [ [Object] ],
Platen: [ [Object] ]
}
}When I was originally looking at the code, I thought the structure of the return statement in get AdfMaxWidth(): number | null and get AdfMaxHeight(): number | null would handle this, but it throws a TypeError as below:
TypeError: Cannot read properties of undefined (reading '0')
at get AdfMaxWidth [as AdfMaxWidth] (/app/ScanCaps.js:28:45)
at readDeviceCapabilities (/app/readDeviceCapabilities.js:41:84)
at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
at async listenCmd (/app/index.js:27:32)
at async Command.<anonymous> (/app/index.js:211:9)
at async Command.parseAsync (/app/node_modules/commander/lib/command.js:936:5)
at async main (/app/index.js:251:5)Please let me know if I can help out with any other info, and sorry about going to exception catching, I come from the land of hobbyist Python where that seems to be pretty widely accepted practice.
Catches the TypeError that is thrown when a printer without an ADF feature is queried for capabilities. The printer returns nothing under the "ADF" header, which crashes the application. Error handling returns null if this situation is caught.