I think I know what's happening here but no idea how to resolve. It appears that an @ is being prepended to the id variable in the GET request.

When that happens the error occurs, if I modify the get request and remove that @ symbol I get a response that looks like this:

{"@context":"\/parts\/web\/api\/contexts\/Part","@id":"\/parts\/web\/api\/parts?_dc=1510773608949\u0026page=1\u0026start=0\u0026itemsPerPage=50\u0026group={"property":"categoryPath","direction":"ASC"}\u0026order=[{"property":"category.categoryPath","direction":"ASC"},{"property":"name","direction":"ASC"}]\u0026filter=[{"subfilters":[{"subfilters":[],"property":"id","operator":"LIKE","value":"43W"}],"type":"OR"}]","@type":"hydra:PagedCollection","hydra:totalItems":0,"hydra:itemsPerPage":50,"hydra:firstPage":"\/parts\/web\/api\/parts?_dc=1510773608949\u0026start=0\u0026itemsPerPage=50\u0026group={"property":"categoryPath","direction":"ASC"}\u0026order=[{"property":"category.categoryPath","direction":"ASC"},{"property":"name","direction":"ASC"}]\u0026filter=[{"subfilters":[{"subfilters":[],"property":"id","operator":"LIKE","value":"43W"}],"type":"OR"}]","hydra:lastPage":"\/parts\/web\/api\/parts?_dc=1510773608949\u0026start=0\u0026itemsPerPage=50\u0026group={"property":"categoryPath","direction":"ASC"}\u0026order=[{"property":"category.categoryPath","direction":"ASC"},{"property":"name","direction":"ASC"}]\u0026filter=[{"subfilters":[{"subfilters":[],"property":"id","operator":"LIKE","value":"43W"}],"type":"OR"}]","hydra:member":[],"hydra:search":{"@type":"hydra:IriTemplate","hydra:template":"\/parts\/web\/api\/parts{?}","hydra:variableRepresentation":"BasicRepresentation","hydra:mapping":[]}}

This looks like it returns the right response telling the UI to invoke a lookup query...?

So I guess the question is how can we limit this @ from being included in the GET query on the barcode scan?

Ok, as much as this is not a solution, I did find a work around.

I had to modify the following file and everything works now, I'm able to scan the item id and the lookup works as expected:

/src/PartKeepr/DoctrineReflectionBundle/Filter/AdvancedSearchFilter.php

Modify line 353 From:

$filter->setProperty($data->property);
To:
$filter->setProperty(str_replace("@","",$data->property));

Basically it's the @ symbol that is causing the problem and it needs to be removed from the GET Ajax request. I'm not exactly sure where to make that change but this doing the above did work for me as a temporary fix until someone can chime in as to how to achieve this properly...

Got the same issue, seems to be the same than https://github.com/partkeepr/PartKeepr/issues/894

Better workaround is to replace property name directly in src/PartKeepr/DoctrineReflectionBundle/Filter/AssociationPropertyTrait.php

public function setProperty($property)
{
    $this->property = str_replace("@", "", $property);
}