Using parser nginx results in error "uninitialized constant Fluent::Plugin::RegexpParser"

[rb-johnmurphy]

fluentd version 0.14.12

When trying to use the nginx parser, fluentd crashes with the error

2017-02-09 22:26:13 +0000 [error]: #0 unexpected error error_class=NameError error="uninitialized constant Fluent::Plugin::RegexpParser"

The fluentd config looks like

<source>
  @type  forward
  @id    input1
  @label @mainstream
  port  24224
</source>

<label @mainstream>
  <filter docker.nginx.**>
    @type parser
    format nginx
    key_name log
  </filter>

  <match docker.**>
    @type stdout
  </match>
</label>

[repeatedly]

It is a bug. #1459 fixes it.

[rb-johnmurphy]

👍 thanks.