Mongodb plugin should output 2 measurements in test mode

[9999dude]

Mongodb plugin is not returning any output since upgrade from 0.1.9 to 0.2.0. The operating system is Centos 6.5.

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# rpm -qa|grep telegraf
telegraf-0.1.9-1.x86_64

# /opt/telegraf/telegraf -config /etc/opt/telegraf/telegraf.conf -test -filter system:mongodb
map[influxdb:0x5256e0 kafka:0x5261e0 opentsdb:0x528420 amqp:0x521c50 datadog:0x523ec0]
OUTPUT ENABLED:  influxdb
* Plugin: mongodb Collection 1
* Plugin: mongodb Collection 2
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_commands_per_sec value=8
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_flushes_per_sec value=0
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_active_writes value=0
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_queries_per_sec value=4
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_updates_per_sec value=52
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_deletes_per_sec value=0
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_net_in_bytes value=12080
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_net_out_bytes value=30818
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_inserts_per_sec value=0
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_vsize_megabytes value=5806
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_resident_megabytes value=1993
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_queued_reads value=0
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_open_connections value=117
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_getmores_per_sec value=4
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_queued_writes value=0
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_active_reads value=1
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_repl_inserts_per_sec value=0
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_repl_queries_per_sec value=0
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_repl_updates_per_sec value=0
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_repl_deletes_per_sec value=0
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_repl_getmores_per_sec value=0
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_repl_commands_per_sec value=0
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_member_status value=PRI
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_percent_cache_dirty value=0.4
> [hostname="127.0.0.1:27017" state="PRI"] mongodb_percent_cache_used value=22.5
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# rpm -qa|grep telegraf
telegraf-0.2.0-1.x86_64

# /opt/telegraf/telegraf -config /etc/opt/telegraf/telegraf.conf -test -filter system:mongodb
* Plugin: mongodb, Collection 1
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[sparrc]

This is sort of expected behavior.

Since those values are "derived" metrics based on 2 measurements, they can only be output after taking two measurements. Currently only the cpu plugin takes 2 measurements in test mode, which is something I changed in version 0.2.0.

I will add a switch for outputting 2 measurements for mongodb plugin in test mode.

tldr this is only a problem of -test mode, if you run telegraf you will find it outputting measurements properly.