Pinterest Secor

Secor is a service persisting Kafka logs to Amazon S3.

Key features

• strong consistency: as long as Kafka is not dropping messages (e.g., due to aggresive cleanup policy) before Secor is able to read them, it is guaranteed that each message will be saved in exacly one S3 file. This property is not compromized by the notorious temporal inconsisteny of S3 caused by the eventual consistency model,
• fault tolerance: any component of Secor is allowed to crash at any given point without compromising data integrity,
• load distribution: Secor may be distributed across multiple machines,
• horizontal scalability: scaling the system out to handle more load is as easy as starting extra Secor processes. Reducing the resource footprint can be achieved by killing any of the running Secor processes. Neither ramping up nor down has any impact on data consistency,
• output partitioning: Secor parses incoming messages and puts them under partitioned s3 paths to enable direct import into systems like Hive,
• configurable upload policies: commit points controlling when data is persisted in S3 are configured through size-based and time-based policies (e.g., upload data when local buffer reaches size of 100MB and at least once per hour),
• monitoring: metrics tracking various performace properties are exposed through Ostrich and optionaly exported to OpenTSDB,
• customizability: external log message parser may be loaded by updating the configuration,
• Qubole interface: Secor connects to Qubole to add finalized output partitions to Hive tables.

Setup Guide

Get Secor code

git clone [git-repo-url] secor
cd secor

Customize configuration parameters

Edit src/main/config/*.properties files to specify parameters describing the environment. Those files contain comments describing the meaning of individual parameters.

Create and install jars

mvn package
mkdir ${SECOR_INSTALL_DIR} # directory to place Secor binaries in.
tar -zxvf target/secor-0.1-SNAPSHOT-bin.tar.gz -C ${SECOR_INSTALL_DIR}

Run tests (optional)

cd ${SECOR_INSTALL_DIR}
./scripts/run_tests.sh

Run Secor

cd ${SECOR_INSTALL_DIR}
java -ea -Dsecor_group=secor_backup -Dlog4j.configuration=log4j.prod.properties -Dconfig=secor.prod.backup.properties -cp secor-0.1-SNAPSHOT.jar:lib/* com.pinterest.secor.main.ConsumerMain

Output grouping

One of the convenience features of Secor is the ability to group messages and save them under common file prefixes. The partitioning is controlled by a message parser. Secor comes with the following parsers:

• offset parser: parser that groups messages based on offset ranges. E.g., messages with offsets in range 0 to 999 will end up under s3n://bucket/topic/offset=0/, offsets 1000 to 2000 will go to s3n://bucket/topic/offset=1000/. To use this parser, start Secor with properties file secor.prod.backup.properties.

• thrift date parser: parser that extracts timestamps from thrift messages and groups the output based on the date (at a day granularity). To keep things simple, this parser assumes that the timestamp is carried in the first field (id 0) of the thrift message schema. The timestamp may be expressed either in seconds or milliseconds, or nanoseconds since the epoch. The output goes to date-partitioned paths (e.g., s3n://bucket/topic/dt=2014-05-01, s3n://bucket/topic/dt=2014-05-02). Date pertitioning is particularly convenient if the output is to be consumed by ETL tools such as Hive. To use this parser, start Secor with properties file secor.prod.partition.properties. You may override the field used to extract the timestamp by setting the "message.timestamp.name" property.

• JSON date parser: parser that extracts timestamps from JSON messages and groups the output based on the date, similar to the Thrift parser above. To use this parser, start Secor with properties file secor.prod.partition.properties and set secor.message.parser.class=com.pinterest.secor.parser.JsonMessageParser. You may override the field used to extract the timestamp by setting the "message.timestamp.name" property.

If none of the parsers available out-of-the-box is suitable for your use case, note that it is very easy to implement a custom parser. All you have to do is to extend MessageParser and tell Secor to use your parser by setting secor.message.parser.class in the properties file.

Tools

Secor comes with a number of tools impelementing interactions with the environment.

Log file printer

Log file printer displays the content of a log file.

java -ea -Dlog4j.configuration=log4j.prod.properties -Dconfig=secor.prod.backup.properties -cp "secor-0.1-SNAPSHOT.jar:lib/*" com.pinterest.secor.main.LogFilePrinterMain -f s3n://bucket/path

Log file verifier

Log file verifier checks the consistency of log files.

java -ea -Dlog4j.configuration=log4j.prod.properties -Dconfig=secor.prod.backup.properties -cp "secor-0.1-SNAPSHOT.jar:lib/*" com.pinterest.secor.main.LogFileVerifierMain -t topic -q

Partition finalizer

Topic finalizer writes _SUCCESS files to date partitions that very likely won't be receiving any new messages and (optionaly) adds the corresponding dates to Hive through Qubole API.

java -ea -Dlog4j.configuration=log4j.prod.properties -Dconfig=secor.prod.backup.propertie -cp "secor-0.1-SNAPSHOT.jar:lib/*" com.pinterest.secor.main.PartitionFinalizerMain

Progress monitor

Progress monitor exports offset consumption lags per topic partition to OpenTSDB. Lags track how far Secor is behind the producers.

java -ea -Dlog4j.configuration=log4j.prod.properties -Dconfig=secor.prod.backup.properties -cp "secor-0.1-SNAPSHOT.jar:lib/*" com.pinterest.secor.main.ProgressMonitorMain

Detailed design

Design details are available in DESIGN.md.

License

Secor is distributed under Apache License, Version 2.0.

Maintainers

• Pawel Garbacki

Contributors

• Andy Kramolisch
• Brenden Matthews
• Lucas Zago

Help

If you have any questions or comments, you can reach us at secor-users@googlegroups.com