| layout | title | license |
|---|---|---|
global |
Accessing OpenStack Swift from Spark |
Licensed to the Apache Software Foundation (ASF) under one or more
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this work for additional information regarding copyright ownership.
The ASF licenses this file to You under the Apache License, Version 2.0
(the "License"); you may not use this file except in compliance with
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http://www.apache.org/licenses/LICENSE-2.0
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See the License for the specific language governing permissions and
limitations under the License.
|
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.
The current Swift driver requires Swift to use the Keystone authentication method, or
its Rackspace-specific predecessor.
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, which can
be done by including the hadoop-cloud module for the specific version of spark used.
For example, for Maven support, add the following to the pom.xml file:
{% highlight xml %} ... org.apache.spark hadoop-cloud_2.12 ${spark.version} ... {% endhighlight %}
Create core-site.xml and place it inside Spark's conf directory.
The main category of parameters that should be configured is the authentication parameters
required by Keystone.
The following table contains a list of Keystone mandatory parameters. PROVIDER can be
any (alphanumeric) 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 whether to use the public (off cloud) or private (in cloud; no transfer fees) endpoints | 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.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.