Astyanax - Cassandra Client

Quick overview of Netflix' Astyanax with usage examples, CQL and composite keys.

Transcript

1. Astyanax - Cassandra Client Ken Michie 9/5/2013 Wednesday, September 4, 13
2. • Java Client • Wraps Cassandra’s Thrift interface • Project began as Hector refactor • Connection Pooling • Round Robin, Token Aware, Bag of Connections • Fault tolerance, retry policies • Simplified API - ‘fluent API’ • Granular queries • CQL(3) • Recipes and Utilities • Common Patterns, etc Astyanax, the son of Hector Wednesday, September 4, 13
3. Connection Pool • Context based • Automatic failover • Host partitioning - token ranges • Pluggable components • Host selection (RR, Latency, etc.) • Retry strategies • Discovery strategies • Implementations: RR, Token Aware, Bag of Connections Wednesday, September 4, 13
4. Latency Awareness • Connection pool can be latency aware • Not by default • Node starts compacting, different rack might be faster • Pluggable implementations: • SMA/EMA included (Simple Moving Average or Exponential Moving Average) • SMA works well enough Wednesday, September 4, 13
5. Fluent API • Operations based on Keyspace • Serializers embedded • Specify: ColumnFamily, Row, Column • CQL & CQL3 support • Specify R/W consistency levels Wednesday, September 4, 13
6. Contexts, Keyspaces & Column Families, Oh My! Context Keyspace Column Family Row Column Row Column Column Row Column Column ‣Discovery ‣ Connection Pool ‣Num Connections ‣Type ‣ R/W Consistency, ‣Fault Tolerance ‣Replication Factor ‣Replication Strategy ‣Serializers ‣Rows and Columns ‣Schemaless(ish) Data! Column Each Circle contains 1 or more sub-circle Wednesday, September 4, 13
7. Create Keyspace Wednesday, September 4, 13
8. Create Keyspace Single DC Multi DC Wednesday, September 4, 13
9. Create Keyspace 3 Replicas per DC Wednesday, September 4, 13
10. Column Family • static ColumnFamily • Create on KeySpace • Serializers (data type) Wednesday, September 4, 13
11. Column Family • static ColumnFamily • Create on KeySpace • Serializers (data type) ValueSerializer KeySerializer Wednesday, September 4, 13
12. Column Family • static ColumnFamily • Create on KeySpace • Serializers (data type) Defined once Wednesday, September 4, 13
13. Reading and Writing • Singular Write • Implicit Serialization • Batch Writes • Multi-key • Multi-column Wednesday, September 4, 13
14. Enter CQL!! Easy, but it gets easier Wednesday, September 4, 13
15. CQL(3) • Use Cassandra as if it was SQL • CREATE TABLE xxx (yyy, zzz) • SELECT xxx FROM yyy WHERE aaa = ‘bbb’; • DELETE xxx FROM yyy; • INSERT INTO xxx (yyy) VALUES (zzz) • CQL3 allows composite, primary keys! Wednesday, September 4, 13
16. CQL(3) Example Queries CREATE TABLE results (searched_value varchar, searched_type varchar, st_name varchar, version varchar, last_update timestamp, result varchar, rawData varchar, statusCode varchar, statusText varchar, uri varchar, PRIMARY KEY (searched_value, searched_type, st_name, version)); INSERT INTO results (searched_value, searched_type, st_name, version, last_update, result, rawData, statusCode, statusText, uri) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?); SELECT * FROM results WHERE searched_value=? AND searched_type=? AND st_name=? AND version=?; Wednesday, September 4, 13
17. CQL(3) Example Queries CREATE TABLE results (searched_value varchar, searched_type varchar, st_name varchar, version varchar, last_update timestamp, result varchar, rawData varchar, statusCode varchar, statusText varchar, uri varchar, PRIMARY KEY (searched_value, searched_type, st_name, version)); INSERT INTO results (searched_value, searched_type, st_name, version, last_update, result, rawData, statusCode, statusText, uri) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?); SELECT * FROM results WHERE searched_value=? AND searched_type=? AND st_name=? AND version=?; Composite Key Wednesday, September 4, 13
18. CQL Inserting Wednesday, September 4, 13
19. CQL Inserting Column Family Injected Keyspace Wednesday, September 4, 13
20. CQL Inserting Composite Key Type Assignment Dynamic Value Type Assignment Wednesday, September 4, 13
21. CQL Inserting Astyanax Implicitly Lower Cases ALL column names (Not VALUES) Wednesday, September 4, 13
22. Recipes Wednesday, September 4, 13
23. Links, etc • http://techblog.netflix.com/2012/01/ announcing-astyanax.html • https://github.com/Netflix/astyanax/wiki • compile 'com.netflix.astyanax:astyanax:1.56.42' Wednesday, September 4, 13