streams able to perform or logic

[Wong Hong Han]

We would like to have item_filters to have OR behaviour if possible.

As of now we are filtering thru `supported` key.
However there is a request to add unsupported version to the simplestreams and we have to revert back to `release` key.

We have to maintain the list for every ubuntu release and EOL after revert to `release` key.

It would be nice to have a OR logic where we can select if the item_filters can contain `supported=true` or `release~(trusty|xenial)`

[Thomas Bechtold (toabctl)]

Hi Wong,

thanks for reporting this bug.

> However there is a request to add unsupported version to the simplestreams and we have to revert back to `release` key.

I don't understand that. Could you give a more detailed example including which stream you use exactly, which fields you use to query and what this "request" is about?

[Wong Hong Han (honghan)]

Hi Thomas,

As of now we have this query set in charm
item_filters: [ "supported~(true|True)", "arch~(x86_64|amd64|arm64|riscv64|s390x|ppc64el)", "ftype~(disk1.img|disk.img)" ]

Where in the charm it will run this command
/snap/bin/simplestreams.sstream-mirror-glance --path streams/v1/index.sjson http://cloud-images.ubuntu.com/releases/ supported~(true|True) arch~(x86_64|amd64|arm64|riscv64|s390x|ppc64el) ftype~(disk1.img|disk.img)

This setting help us to keep the sync images up to date with supported tags
However we have request to add unsupported images but yet to EOL.[1]

From the item_filters code, we can see the filter arguments will be combined with logical AND. [2]
We would like to have an option to maintain the current `supported~(true|True)` tag and include additional `release~(trusty|xenial)`.

Hope this clarify our use case.

1. https://wiki.ubuntu.com/Releases
2. https://git.launchpad.net/simplestreams/tree/bin/sstream-mirror-glance#n102