ENH: implement cleandb feature

[sciunto]

Hi,

In this PR, i propose a new function to solve this issue: #33
It basically combines reset and run functions.

Thank you!

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[wking]

On Sun, Jun 14, 2015 at 06:21:16AM -0700, François Boulogne wrote:

In this PR, i propose a new function to solve this issue: #33
It basically combines reset and run functions.

This approach is going to be racy. If you run:

$ r2e run
$ r2e cleandb

you risk cleaning (and never getting mail for) any posts that go up
between ‘run’ checking a feed and ‘cleandb’ checking it again. I
think a safer approach would be to add a timestamps to the ‘seen’
entries, and then add logic to ‘run’ (or a separate ‘clean’ command)
that removes entries from ‘seen’ if they're older than a configurable
expiration duration (defaulting to 90 days?). How does that sound?

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You don't have to paste the DCO text into your PR to certify it, you
need to add a Signed-off-by tag to your commit message. You can do
this for this branch with something like:

$ git checkout clean # the branch you're using for the PR
$ git commit --amend -s # add your Signed-off-by to the tip commit
$ git push --force sciunto clean # clobber your old ‘clean’ branch with the updated version

[sciunto]

Yes, your proposition is better than mine. For my usecase, I was ok with the risk you mention, but your option is definitely the good one.

[wking]

On Fri, Dec 18, 2015 at 04:53:44PM -0800, François Boulogne wrote:

… your option is definitely the good one.

Do you have time to take a stab at it? I've been trying to catch back
up with rss2email, but the seen entries show up in a number of places
and I haven't tracked down all potentially-affected code.
Alternatively, we can wait until I have time to get a PR out, and
suggest folks use your patch in the interim if they need to trim their
cache.

[sciunto]

I'm afraid I won't. My only chance is during these holidays but I already have a long todo list... :(

[wking]

On Sat, Dec 19, 2015 at 12:34:54PM -0800, François Boulogne wrote:

I'm afraid I won't. My only chance is during these holidays but I
already have a long todo list... :(

No worries ;). If nobody else gets to it first, I'll probably have
time before February.

[Ekleog]

@sciunto This looks not-ready-to-be-merged, and rss2email's repository moved to https://github.com/rss2email/rss2email/ following maintainership changes, so feel free to close here and reopen your PR there if you think it should be tracked over there! :)