fluent-plugin-mongo provides input and output plugins for Fluentd (GitHub)
|fluent-plugin-mongo| fluentd | ruby | |-------------------|------------|--------| | >= 1.0.0 | >= 0.14.12 | >= 2.1 | | < 1.0.0 | >= 0.12.0 | >= 1.9 |
The gem is hosted at Rubygems.org. You can install the gem as follows:
$ fluent-gem install fluent-plugin-mongo
Store Fluentd event to MongoDB database.
Use mongo type in match.
<match mongo.**> @type mongo # You can choose two approaches, connection_string or each parameter # 1. connection_string for MongoDB URI connection_string mongodb://fluenter:10000/fluent # 2. specify each parameter database fluent host fluenter port 10000 # collection name to insert collection test # Set 'user' and 'password' for authentication. # These options are not used when use connection_string parameter. user handa password shinobu # Set 'capped' if you want to use capped collection capped capped_size 100m # Other buffer configurations here </match>
For connection_string parameter, see docs.mongodb.com/manual/reference/connection-string/ article for more detail.
fluent-plugin-mongo support built-in placeholders. database and collection parameters can handle them.
Here is an example to use built-in placeholders:
<match mongo.**>
@type mongo
database ${tag[0]}
# collection name to insert
collection ${tag[1]}-%Y%m%d
# Other buffer configurations here
<buffer tag, time>
@type memory
timekey 3600
</buffer>
</match>
In more detail, please refer to the officilal document for built-in placeholders: docs.fluentd.org/v1.0/articles/buffer-section#placeholders
Tag mapped to MongoDB collection automatically.
Use tag_mapped parameter in match of mongo type.
If tag name is “foo.bar”, auto create collection “foo.bar” and insert data.
<match forward.*> @type mongo database fluent # Set 'tag_mapped' if you want to use tag mapped mode. tag_mapped # If tag is "forward.foo.bar", then prefix "forward." is removed. # Collection name to insert is "foo.bar". remove_tag_prefix forward. # This configuration is used if tag not found. Default is 'untagged'. collection misc # Other configurations here </match>
Replica Set version of mongo.
<match mongo.**> @type mongo_replset database fluent collection logs nodes localhost:27017,localhost:27018 # The replica set name replica_set myapp # num_retries is threshold at failover, default is 60. # If retry count reached this threshold, mongo plugin raises an exception. num_retries 30 # following optional parameters passed to mongo-ruby-driver. # See mongo-ruby-driver docs for more detail: https://docs.mongodb.com/ruby-driver/master/tutorials/ruby-driver-create-client/ # Specifies the read preference mode #read secondary </match>
Use mongo_replset type in match.
<match mongo.**> @type mongo_replset database fluent collection logs # each node separated by ',' nodes localhost:27017,localhost:27018,localhost:27019 # following optional parameters passed to mongo-ruby-driver. #name replset_name #read secondary #refresh_mode sync #refresh_interval 60 #num_retries 60 </match>
Tail capped collection to input data.
Use mongo_tail type in source.
<source> @type mongo_tail database fluent collection capped_log tag app.mongo_log # waiting time when there is no next document. default is 1s. wait_time 5 # Convert 'time'(BSON's time) to fluent time(Unix time). time_key time # Convert ObjectId to string object_id_keys ["id_key"] </source>
You can also use url to specify the database to connect.
<source> @type mongo_tail url mongodb://user:password@192.168.0.13:10249,192.168.0.14:10249/database collection capped_log ... </source>
This allows the plugin to read data from a replica set.
You can save last ObjectId to tail over server’s shutdown to file.
<source> ... id_store_file /Users/repeatedly/devel/fluent-plugin-mongo/last_id </source>
Or Mongo collection can be used to keep last ObjectID.
<source> ... id_store_collection last_id </source>
Make sure the collection is capped. The plugin inserts records but does not remove at all.
BSON records which include ‘.’ or start with ‘$’ are invalid and they will be stored as broken data to MongoDB. If you want to sanitize keys, you can use replace_dot_in_key_with and replace_dollar_in_key_with.
<match forward.*> ... # replace '.' in keys with '__dot__' replace_dot_in_key_with __dot__ # replace '$' in keys with '__dollar__' # Note: This replaces '$' only on first character replace_dollar_in_key_with __dollar__ ... </match>
NOTE: This feature will be removed since v0.8
Fluentd event sometimes has an invalid record as a BSON. In such case, Mongo plugin marshals an invalid record using Marshal.dump and re-inserts its to same collection as a binary.
If passed following invalid record:
{"key1": "invalid value", "key2": "valid value", "time": ISODate("2012-01-15T21:09:53Z") }
then Mongo plugin converts this record to following format:
{"__broken_data": BinData(0, Marshal.dump result of {"key1": "invalid value", "key2": "valid value"}), "time": ISODate("2012-01-15T21:09:53Z") }
Mongo-Ruby-Driver cannot detect an invalid attribute, so Mongo plugin marshals all attributes excluding Fluentd keys(“tag_key” and “time_key”).
You can deserialize broken data using Mongo and Marshal.load. Sample code is below:
# _collection_ is an instance of Mongo::Collection collection.find({'__broken_data' => {'$exists' => true}}).each do |doc| p Marshal.load(doc['__broken_data'].to_s) #=> {"key1": "invalid value", "key2": "valid value"} end
If you want to ignore an invalid record, set true to ignore_invalid_record parameter in match.
<match forward.*> ... # ignore invalid documents at write operation ignore_invalid_record true ... </match>
If you want to exclude some fields from broken data marshaling, use exclude_broken_fields to specfiy the keys.
<match forward.*>
...
# key2 is excluded from __broken_data.
# e.g. {"__broken_data": BinData(0, Marshal.dump result of {"key1": "invalid value"}), "key2": "valid value", "time": ISODate("2012-01-15T21:09:53Z")
exclude_broken_fields key2
...
</match>
Specified value is a comma separated keys(e.g. key1,key2,key3). This parameter is useful for excluding shard keys in shard environment.
Mongo plugin has the limitation of buffer size. Because MongoDB and mongo-ruby-driver checks the total object size at each insertion. If total object size gets over the size limitation, then MongoDB returns error or mongo-ruby-driver raises an exception.
So, Mongo plugin resets buffer_chunk_limit if configurated value is larger than above limitation:
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Before v1.8, max of buffer_chunk_limit is 2MB
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After v1.8, max of buffer_chunk_limit is 8MB
You can tail mongo capped collection.
$ mongo-tail -f
Run following command:
$ bundle exec rake test
You can use ‘mongod’ environment variable for specified mongod:
$ mongod=/path/to/mongod bundle exec rake test
Note that source code in test/tools are from mongo-ruby-driver.
- Copyright
-
Copyright © 2011- Masahiro Nakagawa
- License
-
Apache License, Version 2.0