Legacy IBM COS support

Примечание

Ниже приведена оригинальная документация Trino. Скоро мы ее переведем на русский язык и дополним полезными примерами.

Configure the Hive коннектор to support IBM Cloud Object Storage COS access.

Предупреждение

Legacy support is not recommended and will be removed. Use S3 file system support.

Configuration

To use legacy support, the fs.hadoop.enabled property must be set to true in your catalog configuration file.

To use COS, you need to configure a catalog file to use the Hive connector. For example, create a file etc/ibmcos.properties and specify the path to the COS service config file with the hive.cos.service-config property.

connector.name=hive
hive.cos.service-config=etc/cos-service.properties

The service configuration file contains the access and secret keys, as well as the endpoints for one or multiple COS services:

service1.access-key=<your-access-key1>
service1.secret-key=<your-secret-key1>
service1.endpoint=<endpoint1>
service2.access-key=<your-access-key2>
service2.secret-key=<your-secret-key2>
service2.endpoint=<endpoint2>

The endpoints property is optional. service1 and service2 are placeholders for unique COS service names. The granularity for providing access credentials is at the COS service level.

To use IBM COS service, specify the service name, for example: service1 in the COS path. The general URI path pattern is cos://<bucket>.<service>/object(s).

cos://example-bucket.service1/orders_tiny

Trino translates the COS path, and uses the service1 endpoint and credentials from cos-service.properties to access cos://example-bucket.service1/object.

The Hive Metastore (HMS) does not support the IBM COS filesystem, by default. The Stocator library is a possible solution to this problem. Download the Stocator JAR, and place it in Hadoop PATH. The Stocator IBM COS configuration should be placed in core-site.xml. For example:

<property>
        <name>fs.stocator.scheme.list</name>
        <value>cos</value>
</property>
<property>
        <name>fs.cos.impl</name>
        <value>com.ibm.stocator.fs.ObjectStoreFileSystem</value>
</property>
<property>
        <name>fs.stocator.cos.impl</name>
        <value>com.ibm.stocator.fs.cos.COSAPIClient</value>
</property>
<property>
        <name>fs.stocator.cos.scheme</name>
        <value>cos</value>
</property>
<property>
    <name>fs.cos.service1.endpoint</name>
    <value>http://s3.eu-de.cloud-object-storage.appdomain.cloud</value>
</property>
<property>
    <name>fs.cos.service1.access.key</name>
    <value>access-key</value>
</property>
<property>
    <name>fs.cos.service1.secret.key</name>
    <value>secret-key</value>
</property>

Alternative configuration using S3 compatibility

Use the S3 properties for the Hive connector in the catalog file. If only one IBM Cloud Object Storage endpoint is used, then the configuration can be simplified:

hive.s3.endpoint=http://s3.eu-de.cloud-object-storage.appdomain.cloud
hive.s3.aws-access-key=access-key
hive.s3.aws-secret-key=secret-key

Use s3 protocol instead of cos for the table location:

s3://example-bucket/object/