The datastore should understand how to go from Blob -> URI.
In the case of S3 it does and uses Blob.getContentId().
If the datastore doesnt know how to do it, then its not supported by the
datastore.
You might need a DataStore.getSignedURI(Blob b) method.
On 24 August 2017 at 08:27, Chetan Mehrotra <chetan.mehro...@gmail.com>
wrote:
> > Fair point. So this is more about dynamic adaptability than future
> > extendibility. But AFIU this could still be achieved without the full
> > adaptable machinery:
> >
> > if (binProp instanceOf SignableBin) {
> > URI uri = ((SignableBin) binProp).getSignedURI();
> > if (uri != null) {
> > // resolve URI etc.
> > }
> > }
>
> This would be tricky. The current logic is like below.
>
> 1. Oak JCR BinaryImpl holds a ValueImpl
> 2. ValueImpl -> PropertyState -> Blob
> 3. From Blob following paths are possible
> - Blob -> SegmentBlob -> BlobStoreBlob -> DataRecord -> S3DataRecord
> - Blob -> ArrayBasedBlob
> - Blob ... MongoBlob
>
> So at JCR level where we have a PropertyState we cannot determine if
> the Blob provided by it can provide a signed binary without adding
> such instance of check at each place. Hence the adaptor based proposal
>
> Chetan Mehrotra
>
