HTTP

The http output plugin allows to flush your records into a HTTP endpoint. For now the functionality is pretty basic and it issues a POST request with the data records in MessagePack (or JSON) format.

Configuration Parameters

Key	Description	default
host	IP address or hostname of the target HTTP Server	127.0.0.1
http_User	Basic Auth Username
http_Passwd	Basic Auth Password. Requires HTTP_User to be set
AWS_Auth	Enable AWS SigV4 authentication	false
AWS_Service	Specify the AWS service code, i.e. es, xray, etc., of your service, used by SigV4 authentication. Usually can be found in the service endpoint's subdomains, protocol://service-code.region-code.amazonaws.com
AWS_Region	Specify the AWS region of your service, used by SigV4 authentication
AWS_STS_Endpoint	Specify the custom sts endpoint to be used with STS API, used with the AWS_Role_ARN option, used by SigV4 authentication
AWS_Role_ARN	AWS IAM Role to assume, used by SigV4 authentication
AWS_External_ID	External ID for the AWS IAM Role specified with aws_role_arn, used by SigV4 authentication
port	TCP port of the target HTTP Server	80
Proxy	Specify an HTTP Proxy. The expected format of this value is http://HOST:PORT. Note that HTTPS is not currently supported. It is recommended not to set this and to configure the HTTP proxy environment variables instead as they support both HTTP and HTTPS.
uri	Specify an optional HTTP URI for the target web server, e.g: /something	/
compress	Set payload compression mechanism. Option available is 'gzip'
format	Specify the data format to be used in the HTTP request body, by default it uses msgpack. Other supported formats are json, json_stream and json_lines and gelf.	msgpack
allow_duplicated_headers	Specify if duplicated headers are allowed. If a duplicated header is found, the latest key/value set is preserved.	true
log_response_payload	Specify if the response paylod should be logged or not.	true
header_tag	Specify an optional HTTP header field for the original message tag.
header	Add a HTTP header key/value pair. Multiple headers can be set.
json_date_key	Specify the name of the time key in the output record. To disable the time key just set the value to false.	date
json_date_format	Specify the format of the date. Supported formats are double, epoch, iso8601 (eg: 2018-05-30T09:39:52.000681Z) and java_sql_timestamp (eg: 2018-05-30 09:39:52.000681)	double
gelf_timestamp_key	Specify the key to use for timestamp in gelf format
gelf_host_key	Specify the key to use for the host in gelf format
gelf_short_message_key	Specify the key to use as the short message in gelf format
gelf_full_message_key	Specify the key to use for the full message in gelf format
gelf_level_key	Specify the key to use for the level in gelf format
body_key	Specify the key to use as the body of the request (must prefix with "$"). The key must contain either a binary or raw string, and the content type can be specified using headers_key (which must be passed whenever body_key is present). When this option is present, each msgpack record will create a separate request.
headers_key	Specify the key to use as the headers of the request (must prefix with "$"). The key must contain a map, which will have the contents merged on the request headers. This can be used for many purposes, such as specifying the content-type of the data contained in body_key.
workers	The number of workers to perform flush operations for this output.	2

TLS / SSL

HTTP output plugin supports TLS/SSL, for more details about the properties available and general configuration, please refer to the TLS/SSL section.

Getting Started

In order to insert records into a HTTP server, you can run the plugin from the command line or through the configuration file:

Command Line

The http plugin, can read the parameters from the command line in two ways, through the -p argument (property) or setting them directly through the service URI. The URI format is the following:

http://host:port/something

Using the format specified, you could start Fluent Bit through:

$ fluent-bit -i cpu -t cpu -o http://192.168.2.3:80/something -m '*'

Configuration File

In your main configuration file, append the following Input & Output sections:

fluent-bit.conf

[INPUT]
    Name  cpu
    Tag   cpu

[OUTPUT]
    Name  http
    Match *
    Host  192.168.2.3
    Port  80
    URI   /something

fluent-bit.yaml

pipeline:
    inputs:
        - name: cpu
          tag:  cpu
    outputs:
        - name: http
          match: '*'
          host: 192.168.2.3
          port: 80
          URI: /something

By default, the URI becomes tag of the message, the original tag is ignored. To retain the tag, multiple configuration sections have to be made based and flush to different URIs.

Another approach we also support is the sending the original message tag in a configurable header. It's up to the receiver to do what it wants with that header field: parse it and use it as the tag for example.

To configure this behaviour, add this config:

fluent-bit.conf

[OUTPUT]
    Name  http
    Match *
    Host  192.168.2.3
    Port  80
    URI   /something
    Format json
    header_tag  FLUENT-TAG

fluent-bit.yaml

    outputs:
        - name: http
          match: '*'
          host: 192.168.2.3
          port: 80
          URI: /something
          format: json
          header_tag: FLUENT-TAG

Provided you are using Fluentd as data receiver, you can combine in_http and out_rewrite_tag_filter to make use of this HTTP header.

<source>
  @type http
  add_http_headers true
</source>

<match something>
  @type rewrite_tag_filter
  <rule>
    key HTTP_FLUENT_TAG
    pattern /^(.*)$/
    tag $1
  </rule>
</match>

Notice how we override the tag, which is from URI path, with our custom header

Example : Add a header

fluent-bit.conf

[OUTPUT]
    Name           http
    Match          *
    Host           127.0.0.1
    Port           9000
    Header         X-Key-A Value_A
    Header         X-Key-B Value_B
    URI            /something

fluent-bit.yaml

    outputs:
        - name: http
          match: '*'
          host: 127.0.0.1
          port: 9000
          header:
            - X-Key-A Value_A
            - X-Key-B Value_B
          URI: /something

Example : Sumo Logic HTTP Collector

Suggested configuration for Sumo Logic using json_lines with iso8601 timestamps. The PrivateKey is specific to a configured HTTP collector.

fluent-bit.conf

[OUTPUT]
    Name             http
    Match            *
    Host             collectors.au.sumologic.com
    Port             443
    URI              /receiver/v1/http/[PrivateKey]
    Format           json_lines
    Json_date_key    timestamp
    Json_date_format iso8601

fluent-bit.yaml

    outputs:
        - name: http
          match: '*'
          host: collectors.au.sumologic.com
          port: 443
          URI: /receiver/v1/http/[PrivateKey]
          format: json_lines
          json_date_key: timestamp
          json_date_format: iso8601

A sample Sumo Logic query for the CPU input. (Requires json_lines format with iso8601 date format for the timestamp field).

_sourcecategory="my_fluent_bit"
| json "cpu_p" as cpu
| timeslice 1m
| max(cpu) as cpu group by _timeslice