Count decreases when paging with RSM

Question

Count decreases when paging with RSM

Closed this issue 5 years ago · 0 comments

When using a simple date query, and using RSM to limit and page through the results, the count of total matches decreases as I page through.

First query:

<iq to="chat@conference.example.org" id="test1" type="set">
    <query xmlns='urn:xmpp:mam:2' queryid='00003'>
        <x xmlns='jabber:x:data' type='submit'>
            <field var='FORM_TYPE'>
                <value>urn:xmpp:mam:2</value>
            </field>
            <field var='start'>
                <value>2020-01-20T00:00:00.000+00:00</value>
            </field>
        </x>
        <set xmlns='http://jabber.org/protocol/rsm'>
            <max>1</max>
        </set>
    </query>
</iq>

First response:

<message to="userone@example.org/Spark" from="chat@conference.example.org">
    <result xmlns="urn:xmpp:mam:2" queryid="00003" id="1">
        <forwarded xmlns="urn:xmpp:forward:0">
            <delay xmlns="urn:xmpp:delay" stamp="2020-01-20T20:47:21.102Z"/>
            <message xmlns="jabber:client" type="groupchat" from="chat@conference.example.org">
                <subject/>
            </message>
        </forwarded>
    </result>
</message>
<iq type="result" id="test1" from="chat@conference.example.org" to="userone@example.org/Spark">
    <fin xmlns="urn:xmpp:mam:2" queryid="00003">
        <set xmlns="http://jabber.org/protocol/rsm">
            <count>8</count>
        </set>
    </fin>
</iq>

(note the RSM count is 8)

Second query (for page 2 - 1 item after the item with ID "1"):

<iq to="chat@conference.example.org" id="test1" type="set">
    <query xmlns='urn:xmpp:mam:2' queryid='00004'>
        <x xmlns='jabber:x:data' type='submit'>
            <field var='FORM_TYPE'>
                <value>urn:xmpp:mam:2</value>
            </field>
            <field var='start'>
                <value>2020-01-20T00:00:00.000+00:00</value>
            </field>
        </x>
        <set xmlns='http://jabber.org/protocol/rsm'>
            <max>1</max>
            <after>1</after>
        </set>
    </query>
</iq>

Second response:

<message to="userone@example.org/Spark" from="chat@conference.example.org">
    <result xmlns="urn:xmpp:mam:2" queryid="00004" id="2">
        <forwarded xmlns="urn:xmpp:forward:0">
            <delay xmlns="urn:xmpp:delay" stamp="2020-01-20T20:48:28.301Z"/>
            <message xmlns="jabber:client" id="98EDg-107" type="groupchat" from="chat@conference.example.org/XMPP">
                <body>Potato</body>
                <x xmlns="jabber:x:event">
                    <offline/>
                    <delivered/>
                    <displayed/>
                    <composing/>
                </x>
                <stanza-id xmlns="urn:xmpp:sid:0" id="9a959885-0356-4c58-a7a7-bf6f6e75161a" by="chat@conference.example.org"></stanza-id>
            </message>
        </forwarded>
    </result>
</message>
<iq type="result" id="test1" from="chat@conference.example.org" to="userone@example.org/Spark">
    <fin xmlns="urn:xmpp:mam:2" queryid="00004">
        <set xmlns="http://jabber.org/protocol/rsm">
            <first>9a959885-0356-4c58-a7a7-bf6f6e75161a</first>
            <count>7</count>
        </set>
    </fin>
</iq>

See that count had reduced to 7.

This doesn't occur when performing a full text search - this remains at the correct count throughout.