rewrite-tag filter in fluent-bit 1.6.0 hangs on

Question

I tried the rewrite-tag example written in the documentation with fluent-bit 1.6.0

I was able to get rid of the following warning with the fix mentioned in the Git

[2020/10/19 15:17:31] [ warn] [input chunk] no matching route for input chunk 16817-1603100851.153798000.flb

But now I get nothing on the output. It’s hanging on after following line

...
[2020/10/19 15:42:00] [ info] [engine] started (pid=28286)
[2020/10/19 15:42:00] [ info] [storage] version=1.0.6, initializing...
[2020/10/19 15:42:00] [ info] [storage] in-memory
[2020/10/19 15:42:00] [ info] [storage] normal synchronization mode, checksum disabled, max_chunks_up=128
[2020/10/19 15:42:00] [ info] [sp] stream processor started

Any idea why that is?

Following is the content of configuration file (same as in the documentation)

[SERVICE]
    Flush     1
    Log_Level info

[INPUT]
    NAME   dummy
    Dummy  {"tool": "fluent", "sub": {"s1": {"s2": "bit"}}}
    Tag    test_tag

[FILTER]
    Name          rewrite_tag
    Match         test_tag
    Rule          $tool ^(fluent)$  from.$TAG.new.$tool.$sub['s1']['s2'].out false
    Emitter_Name  re_emitted

[OUTPUT]
    Name   stdout
    Match  from.*

I named the configuration file as example.conf

The way I ran it as below

fluent-bit -c example.conf

Answer 1

There is a known regression, please upgrade to v1.6.1:

$ ../../build/bin/fluent-bit -c conf 
Fluent Bit v1.6.1
* Copyright (C) 2019-2020 The Fluent Bit Authors
* Copyright (C) 2015-2018 Treasure Data
* Fluent Bit is a CNCF sub-project under the umbrella of Fluentd
* https://fluentbit.io

[2020/10/19 12:25:49] [ info] [engine] started (pid=1830124)
[2020/10/19 12:25:49] [ info] [storage] version=1.0.6, initializing...
[2020/10/19 12:25:49] [ info] [storage] in-memory
[2020/10/19 12:25:49] [ info] [storage] normal synchronization mode, checksum disabled, max_chunks_up=128
[2020/10/19 12:25:49] [ info] [sp] stream processor started
[0] from.test_tag.new.fluent.bit.out: [1603131950.103238001, {"tool"=>"fluent", "sub"=>{"s1"=>{"s2"=>"bit"}}}]
[0] from.test_tag.new.fluent.bit.out: [1603131951.102535915, {"tool"=>"fluent", "sub"=>{"s1"=>{"s2"=>"bit"}}}]