sqoop/COMPILING.txt

= Compiling

This document explains how to compile Sqoop.

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== Build Dependencies

Compiling Sqoop requires the following tools:

* Apache ant (1.7.1)
* Java JDK 1.6

Additionally, building the documentation requires these tools:

* asciidoc
* make
* python 2.5+
* xmlto
* tar
* gzip

Furthermore, Sqoop's build can be instrumented with the following:

* findbugs (1.3.9) for code quality checks
* cobertura (1.9.4.1) for code coverage
* checkstyle (5.x) for code style checks

== The Basics

Sqoop is compiled with ant. Type +ant -p+ to see the list of available targets.

Type +ant+ to compile all java sources. You can then run Sqoop with +bin/sqoop+.

If you want to build everything (including the documentation), type
+ant package+. This will appear in the
+build/sqoop-(version)/+ directory.

== Testing Sqoop

Sqoop has several unit tests which can be run with +ant test+. This command
will run all the "basic" checks against an in-memory database, HSQLDB.

Sqoop also has compatibility tests that check its ability to work with
several third-party databases. To enable these tests, you will need to install
and configure the databases, and download the JDBC drivers for each one.

=== MySQL

Install MySQL server and client 5.0. Download MySQL Connector/J 5.0.8 for
JDBC. Instructions for configuring the MySQL database are in MySQLAuthTest
and DirectMySQLTest.

=== Oracle

Install Oracle XE (Express edition) 10.2.0. Instructions for configuring the
database are in OracleManagerTest. Download the ojdbc6_g jar.

=== PostgreSQL

Install PostgreSQL 8.3.9. Download the postgresql 8.4 jdbc driver. Instructions
for configuring the database are in PostgresqlTest.

=== Running the Third-party Tests

After the third-party databases are installed and configured, run:

++++
ant test -Dthirdparty=true -Dsqoop.thirdparty.lib.dir=/path/to/jdbc/drivers/
++++


== Multiple Hadoop Distributions

Sqoop can be compiled against different versions of Hadoop. Both the svn
trunk of Apache Hadoop, and Cloudera's Distribution for Hadoop (CDH3)
can be used as the underlying Hadoop implementation.

By default, Sqoop will compile against the latest snapshot from Apache
(retrieved through maven). You can specify the Hadoop distribution to
retrieve with the hadoop.dist property. Valid values are "apache",
"apache21", or "cloudera":

++++
ant jar -Dhadoop.dist=apache # Uses the nightly build of "trunk"
ant jar -Dhadoop.dist=apache21
ant jar -Dhadoop.dist=cloudera
++++

To switch between builds, you will need to clear Ivy's dependency
cache: +ant veryclean+

=== Using a Local Hadoop Installation

Sqoop can be compiled against a locally-installed version of Sqoop,
bypassing the maven repository. To do this you will need to set 
three properties:

- hadoop.dist should be set to "local"
- hadoop.shim should be set to "cloudera" or "apache", to tell Sqoop whether
  to build the Cloudera or Apache-specific shim jar
- hadoop.home should be set to the path where Hadoop is installed.

For example, the following will compile Sqoop against a locally-installed
version of CDH.

++++
ant jar jar-one-shim -Dhadoop.dist=local -Dhadoop.shim=cloudera \
    -Dhadoop.home=/usr/lib/hadoop
++++


== Code Quality Analysis

We have three tools which can be used to analyze Sqoop's code quality.

=== Findbugs

Findbugs detects common errors in programming. New patches should not
trigger additional warnings in Findbugs.

Install findbugs (1.3.9) according to its instructions. To use it,
run:

++++
ant findbugs -Dfindbugs.home=/path/to/findbugs/
++++

A report will be generated in +build/findbugs/+

=== Cobertura

Cobertura runs code coverage checks. It instruments the build and
checks that each line and conditional expression is evaluated along
all possible paths.

Install Cobertura according to its instructions. Then run a test with:

++++
ant clean
ant cobertura -Dcobertura.home=/path/to/cobertura
ant cobertura -Dcobertura.home=/path/to/cobertura \
    -Dthirdparty=true -Dsqoop.thirdparty.lib.dir=/path/to/thirdparty
++++

(You'll need to run the cobertura target twice; once against the regular
test targets, and once against the thirdparty targets.)

When complete, the report will be placed in +build/cobertura/+

New patches should come with sufficient tests for their functionality
as well as their error recovery code paths. Cobertura can help assess
whether your tests are thorough enough, or where gaps lie.

=== Checkstyle

Checkstyle enforces our style guide. There are currently a very small
number of violations of this style in the source code, but hopefully this
will remain the case. New code should not trigger additional checkstyle
warnings.

Checkstyle does not need to be installed manually; it will be retrieved via
Ivy when necessary.

To run checkstyle, execute:

++++
ant checkstyle
++++

A report will be generated as +build/checkstyle-errors.html+


== Deploying to Maven

To use Sqoop as a dependency in other projects, you can pull Sqoop into your
dependency management system through Maven.

To install Sqoop in your local +.m2+ cache, run:

++++
ant mvn-install
++++

This will install a pom and the Sqoop jar.

To deploy Sqoop to a public repository, use:

++++
ant mvn-deploy
++++

By default, this deploys to repository.cloudera.com. You can choose
the complete URL to deploy to with the +mvn.deploy.url+ property.
By default, this deploys to the "snapshots" repository. To deploy to
"staging" or "releases" on repository.cloudera.com, set the
+mvn.repo+ property accordingly.

== Releasing Sqoop

To build a full release of Sqoop, run +ant release -Dversion=(somever)+.
This will build a binary release tarball and the web-based documentation
as well as run a release audit which flags any source files which may
be missing license headers.

(The release audit can be run standalone with the +ant releaseaudit+
target.)

You must set the +version+ property explicitly; you cannot release a
snapshot. To simultaneously deploy this to a maven repository, include
the +mvn-install+ or +mvn-deploy+ targets as well.


== Using Eclipse

Running +ant eclipse+ will generate +.project+ and +.classpath+ files that
will allow you to edit Sqoop sources in Eclipse with all the library
dependencies correctly resolved. To compile the jars, you should still
use ant.