layout | title |
---|---|
global |
Accessing OpenStack Swift from Spark |
Spark's support for Hadoop InputFormat allows it to process data in OpenStack Swift using the
same URI formats as in Hadoop. You can specify a path in Swift as input through a
URI of the form swift://container.PROVIDER/path
. You will also need to set your
Swift security credentials, through core-site.xml
or via
SparkContext.hadoopConfiguration
.
Current Swift driver requires Swift to use Keystone authentication method.
Although not mandatory, it is recommended to configure the proxy server of Swift with
list_endpoints
to have better data locality. More information is
available here.
The Spark application should include hadoop-openstack
dependency.
For example, for Maven support, add the following to the pom.xml
file:
{% highlight xml %} ... org.apache.hadoop hadoop-openstack 2.3.0 ... {% endhighlight %}
Create core-site.xml
and place it inside Spark's conf
directory.
There are two main categories of parameters that should to be configured: declaration of the
Swift driver and the parameters that are required by Keystone.
Configuration of Hadoop to use Swift File system achieved via
Property Name | Value |
---|---|
fs.swift.impl | org.apache.hadoop.fs.swift.snative.SwiftNativeFileSystem |
Additional parameters required by Keystone (v2.0) and should be provided to the Swift driver. Those
parameters will be used to perform authentication in Keystone to access Swift. The following table
contains a list of Keystone mandatory parameters. PROVIDER
can be any name.
Property Name | Meaning | Required |
---|---|---|
fs.swift.service.PROVIDER.auth.url |
Keystone Authentication URL | Mandatory |
fs.swift.service.PROVIDER.auth.endpoint.prefix |
Keystone endpoints prefix | Optional |
fs.swift.service.PROVIDER.tenant |
Tenant | Mandatory |
fs.swift.service.PROVIDER.username |
Username | Mandatory |
fs.swift.service.PROVIDER.password |
Password | Mandatory |
fs.swift.service.PROVIDER.http.port |
HTTP port | Mandatory |
fs.swift.service.PROVIDER.region |
Keystone region | Mandatory |
fs.swift.service.PROVIDER.public |
Indicates if all URLs are public | Mandatory |
For example, assume PROVIDER=SparkTest
and Keystone contains user tester
with password testing
defined for tenant test
. Then core-site.xml
should include:
{% highlight xml %} fs.swift.impl org.apache.hadoop.fs.swift.snative.SwiftNativeFileSystem fs.swift.service.SparkTest.auth.url http://127.0.0.1:5000/v2.0/tokens fs.swift.service.SparkTest.auth.endpoint.prefix endpoints fs.swift.service.SparkTest.http.port 8080 fs.swift.service.SparkTest.region RegionOne fs.swift.service.SparkTest.public true fs.swift.service.SparkTest.tenant test fs.swift.service.SparkTest.username tester fs.swift.service.SparkTest.password testing {% endhighlight %}
Notice that
fs.swift.service.PROVIDER.tenant
,
fs.swift.service.PROVIDER.username
,
fs.swift.service.PROVIDER.password
contains sensitive information and keeping them in
core-site.xml
is not always a good approach.
We suggest to keep those parameters in core-site.xml
for testing purposes when running Spark
via spark-shell
.
For job submissions they should be provided via sparkContext.hadoopConfiguration
.