Saving an object with a byte array in the DB

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Saving an object with a byte array in the DB

Postby d.pearce1417196993 » Thu Feb 12, 2015 1:12 am

I am using an object to store workflow parameters.

This was working fine in a text field where the _response_object contained only strings

{"bywhom":"the solicitor/instructing party","oldidappointments":"B15881EE-1C70-4110-8BB0-795BF9BF6092","appchangereason":"The expert has had to cancel the clinic"}

When adding a pdf into the Object though it starts to go horrible wrong. i just get a 'null'

I have tried switching to a blob field and swtiched the blob serialisation on, but then i get a string back!

I then used iT2Be tools to try and convert what appears to be a string in the blob field that gets stored back to bytes, but the pdf I get back on reading the saved object appears to be 1/3 bigger than in the line before it is saved and blank!

This, I guess is simple, but between my reads and writes, serialisations etc something is going wrong!

Is there a correct way to store a mixed object in the DB, which field type, what serialisation and how do i read it back.

Thanks in advance.

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Re: Saving an object with a byte array in the DB

Postby jcompagner » Tue Feb 17, 2015 12:13 pm

first a question, how do you know how to read it back in if the object can be a string or a pdf? How do you interpreted the bytes?

I guess if you use a plain media type column (blob in db) then you can just push the bytes of the pdf or the bytes of the string (without using serializers on the column itself)
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Re: Saving an object with a byte array in the DB

Postby ROCLASI » Tue Feb 17, 2015 1:09 pm

Hi David,

I think you need to encode the binary (the PDF) with base64 in your object, then serialize it to a JSON and store it in a text column.
This way it's all text and can be de-encoded back to binary.

Hope this helps.
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