journalpump: A Python repository from jvtm

journalpump

journalpump is a daemon that takes log messages from journald and pumps them to a given output. Currently supported outputs are Elasticsearch, Kafka and logplex. It reads messages from journald and optionally checks if they match a config rule and forwards them as JSON messages to the desired output.

Building

To build an installation package for your distribution, go to the root directory of a journalpump Git checkout and then run:

Debian:

make deb

This will produce a .deb package into the parent directory of the Git checkout.

Fedora:

make rpm

This will produce an RPM in rpm/RPMS/noarch/.

Other:

python3 setup.py bdist_egg

This will produce an egg file into a dist directory within the same folder.

journalpump requires Python 3.4 or newer.

Installation

To install it run as root:

Debian:

dpkg -i ../journalpump*.deb

Fedora:

su -c 'dnf install rpm/RPMS/noarch/*'

On Fedora it is recommended to simply run journalpump under systemd:

systemctl enable journalpump.service

and eventually after the setup section, you can just run:

systemctl start journalpump.service

Other:

python3 setup.py install

On systems without systemd it is recommended that you run journalpump within supervisord or similar process control system.

Setup

After installation you need to create a suitable JSON configuration file for your installation.

General notes

If correctly installed, journalpump comes with a single executable, journalpump that takes as an argument the path to journalpump's JSON configuration file.

journalpump is the main process that should be run under systemd or supervisord.

While journalpump is running it may be useful to read the JSON state file that will be created as journalpump_state.json to the current working directory. The JSON state file is human readable and should give an understandable description of the current state of the journalpump.

Top level configuration

Example:

{
    "json_state_file_path": "/var/lib/journalpump/journalpump_state.json",
    "readers": {
       ...
    },
    "statsd":   {
        "host": "127.0.0.1",
        "port": 12345,
        "tags": {
            "sometag": "somevalue"
        }
    }
}

json_state_file_path (default "journalpump_state.json")

Location of a JSON state file which describes the state of the journalpump process.

statsd (default null)

Enables metrics sending to a statsd daemon that supports the influxdb-statsd / telegraf syntax with tags.

The tags setting can be used to enter optional tag values for the metrics.

Metrics sending follows the Telegraf spec.

log_level (default "INFO")

Determines log level of journalpump.

Reader configuration

Reader configuration structure:

{
    "readers": {
        "some_reader": {
            "senders": {
                "some_log": {
                    ...
                },
                "another_log": {
                    ...
                }
            }
        },
        "another_reader": {
            "senders": {
                "some_kafka": {
                    ...
                }
            }
        }
    }
}

Example configuration for a single reader:

{
    "journal_path": "/var/lib/machines/container1/var/log/journal/b09ffd62229f4bd0829e883c6bb12c4e",
    "senders": {
        "k1": {
            "output_type": "kafka",
            "ca": "/etc/journalpump/ca-bundle.crt",
            "certfile": "/etc/journalpump/node.crt",
            "kafka_address": "kafka.somewhere.com:12345",
            "kafka_topic": "journals",
            "keyfile": "/etc/journalpump/node.key",
            "ssl": true
        },
    },
    "searches": [
        {
            "fields": {
                "MESSAGE": "kernel: Out of memory: Kill process .+ \\((?P<process>[^ ]+)\\)"
            },
            "name": "journal.oom_killer"
        }
    ],
    "tags": {
        "type": "container"
    }
}

initial_position (default head)

Controls where the readers starts when the journalpump is launched for the first time:

head: First entry in the journal
tail: Last entry in the journal
<integer>: Seconds from current boot session

match_key (default null)

If you want to match against a single journald field, this configuration key defines the key to match against.

match_value (default null)

If you want to match against a single journald field, this configuration key defines the value to match against. Currently only equality is allowed.

msg_buffer_max_length (default 50000)

How many journal entries to read at most into a memory buffer from which the journalpump feeds the configured logsender.

journal_path (default null)

Path to the directory containing journal files if you want to override the default one.

units_to_match (default [])

Require that the logs message matches only against certain _SYSTEMD_UNITs. If not set, we allow log events from all units.

flags (default LOCAL_ONLY)

"LOCAL_ONLY" opens journal on local machine only; "RUNTIME_ONLY" opens only volatile journal files; and "SYSTEM" opens journal files of system services and the kernel, "CURRENT_USER" opens files of the current user; and "OS_ROOT" is used to open the journal from directories relative to the specified directory path or file descriptor. Multiple flags can be OR'ed together using a list: ["LOCAL_ONLY", "CURRENT_USER"].

Sender Configuration

output_type (default null)

Output to write journal events to. Options are elasticsearch, kafka, file and logplex.

File Sender Configuration

Writes journal entries as JSON to a text file, one entry per line.

file_output sets the path to the output file.

Elasticsearch Sender Configuration

elasticsearch_index_days_max (default 3)

Maximum number of days of logs to keep in Elasticsearch. Relevant when using output_type elasticsearch.

elasticsearch_index_prefix (default journalpump)

Elasticsearch index name to use when Maximum number of days of logs to keep in Elasticsearch. Relevant when using output_type elasticsearch.

elasticsearch_timeout (default 10.0)

Elasticsearch request timeout limit. The default should work for most people but you might need to increase it in case you have a large latency to server or the server is very congested. Required when using output_type elasticsearch.

elasticsearch_url (default null)

Fully qualified elasticsearch url of the form https://username:password@hostname.com:port. Required when using output_type elasticsearch.

Kafka Sender Configuration

ca (default null)

Kafka Certificate Authority path, needed when you're using Kafka with SSL authentication.

certfile (default null)

Kafka client certificate path, needed when you're using Kafka with SSL authentication.

kafka_api_version (default 0.9)

Which Kafka server API version to use.

kafka_topic (default null)

Which Kafka topic do you want the journalpump to write to. Required when using output_type kafka.

kafka_address (default null)

The address of the kafka server which to write to. Required when using output_type kafka.

keyfile (default null)

Kafka client key path, needed when you're using Kafka with SSL authentication.

License

journalpump is licensed under the Apache License, Version 2.0. Full license text is available in the LICENSE file and at http://www.apache.org/licenses/LICENSE-2.0.txt

Credits

journalpump was created by Hannu Valtonen <hannu.valtonen@aiven.io> and is now maintained by Aiven hackers <opensource@aiven.io>.

Recent contributors are listed on the project's GitHub contributors page.

Contact

Bug reports and patches are very welcome, please post them as GitHub issues and pull requests at https://github.com/aiven/journalpump . Any possible vulnerabilities or other serious issues should be reported directly to the maintainers <opensource@aiven.io>.

jvtm/journalpump