| Thrift API for HDFS |
| ================== |
| |
| Introduction: |
| ============ |
| |
| The Hadoop Distributed File System is written in Java. An application |
| that wants to store/fetch data to/from HDFS can use the Java API |
| This means that applications that are not written in Java cannot |
| access HDFS in an elegant manner. |
| |
| Thrift is a software framework for scalable cross-language services |
| development. It combines a powerful software stack with a code generation |
| engine to build services that work efficiently and seamlessly |
| between C++, Java, Python, PHP, and Ruby. |
| |
| This project exposes HDFS APIs using the Thrift software stack. This |
| allows applciations written in a myriad of languages to access |
| HDFS elegantly. |
| |
| |
| The Application Programming Interface (API) |
| =========================================== |
| The HDFS API that is exposed through Thrift can be found in if/hadoopfs.thrift. |
| |
| Compilation |
| =========== |
| The compilation process creates a server org.apache.hadoop.thriftfs.HadooopThriftServer |
| that implements the Thrift interface defined in if/hadoopfs.thrift. |
| |
| Th thrift compiler is used to generate API stubs in python, php, ruby, |
| cocoa, etc. The generated code is checked into the directories gen-*. |
| The generated java API is checked into lib/hadoopthriftapi.jar. |
| |
| There is a sample python script hdfs.py in the scripts directory. This python |
| script, when invoked, creates a HadoopThriftServer in the background, and then |
| communicates wth HDFS using the API. This script is for demonstration purposes |
| only. |
| |
