Not able to retrieve old revisions from Sync Gateway

Mobile Sync Gateway
1

Hi,

We’re using Sync Gateway 2.1 and Server 6.0.

Currently the sync gateway is setup with the following configuration.

		"allow_conflicts": false,
		"revs_limit": 20,

While fetching the raw document from sync gateway admin API, we can see the old revisions in _sync property.
But while fetching the old revision of the document using open_revs option, it’s always returning the latest revision.
Is it because old revisions are not maintained ?

2

If you want the body of an old revision, just use ?rev=REVID. (The open_revs query is used to add a list of revision IDs to the response, but the body of the response is still the current revision.)

3

Jens has responded to your question. But I am curious as to why you need access to the old revision bodies. You have set allow_conflicts as false which means that the system takes care of conflicts for you. Fetching the non-current revision bodies is typically only needed for resolving conflicts.

4

Hi,

We wanted to take a look at the previous revisions for investigating a data issue. Can you please tell us how long Couchbase keeps old revisions before deleting them? Is there a configuration that controls this?

Thanks.

5

Thank you, We tried rev option also, but got a 404 response. It looks like Couchbase is not keeping old revisions for a longer period of time.

6

Sync Gateway will periodically compact away the JSON bodies of non-leaf revisions and that’s based on the TTL/expiration of the document. IIRC, that defaulted to 5 min. You can learn more about this in this blog. I have to double check if this is configurable.

You can set the expiration of current version via the _exp field when you PUT document via the Sync Gateway REST API or via the expiry() function.

You can find out the expiration time of a document using the show_exp parameter on the GET API.

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