How to load PostgreSQL data into Elasticsearch via Logstash

Elasticsearch is a popular distributed full-text search engine. By centrally storing data, you can perform ultra-fast searches, fine-tuning relevance, and powerful analytics with ease. Elasticsearch has a pipeline tool for loading data called "Logstash". You can use CData JDBC Drivers to easily import data from any data source into Elasticsearch for search and analysis.

This article explains how to use the CData JDBC Driver for PostgreSQL to load data from PostgreSQL into Elasticsearch via Logstash.

Using CData JDBC Driver for PostgreSQL with Elasticsearch Logstash

• Install the CData JDBC Driver for PostgreSQL on the machine where Logstash is running.
• The JDBC Driver will be installed at the following path (the year part, e.g. 20XX, will vary depending on the product version you are using). You will use this path later. Place this .jar file (and the .lic file if it's a licensed version) in Logstash.
  C:\Program Files\CData\CData JDBC Driver for PostgreSQL 20XX\lib\cdata.jdbc.postgresql.jar
  
• Next, install the JDBC Input Plugin, which connects Logstash to the CData JDBC driver. The JDBC Plugin comes by default with the latest version of Logstash, but depending on the version, you may need to add it.
  https://www.elastic.co/guide/en/logstash/5.4/plugins-inputs-jdbc.html
• Move the CData JDBC Driver’s .jar file and .lic file to Logstash's "/logstash-core/lib/jars/".

Sending PostgreSQL data to Elasticsearch with Logstash

Now, let's create a configuration file for Logstash to transfer PostgreSQL data to Elasticsearch.

• Write the process to retrieve PostgreSQL data in the logstash.conf file, which defines data processing in Logstash. The input will be JDBC, and the output will be Elasticsearch. The data loading job is set to run at 30-second intervals.
• Set the CData JDBC Driver's .jar file as the JDBC driver library, configure the class name, and set the connection properties to PostgreSQL in the form of a JDBC URL. The JDBC URL allows detailed configuration, so please refer to the product documentation for more specifics.

To connect to PostgreSQL, set the Server, Port (the default port is 5432), and Database connection properties and set the User and Password you wish to use to authenticate to the server. If the Database property is not specified, the data provider connects to the user's default database.

SSH Connectivity for PostgreSQL

You can use SSH (Secure Shell) to authenticate with PostgreSQL, whether the instance is hosted on-premises or in supported cloud environments. SSH authentication ensures that access is encrypted (as compared to direct network connections).

SSH Connections to PostgreSQL in Password Auth Mode

To connect to PostgreSQL via SSH in Password Auth mode, set the following connection properties:

• User: PostgreSQL User name
• Password: PostgreSQL Password
• Database: PostgreSQL database name
• Server: PostgreSQL Server name
• Port: PostgreSQL port number like 3306
• UserSSH: "true"
• SSHAuthMode: "Password"
• SSHPort: SSH Port number
• SSHServer: SSH Server name
• SSHUser: SSH User name
• SSHPassword: SSH Password

SSH Connections to PostgreSQL in Public Key Auth Mode

To connect to PostgreSQL via SSH in Password Auth mode, set the following connection properties:

• User: PostgreSQL User name
• Password: PostgreSQL Password
• Database: PostgreSQL database name
• Server: PostgreSQL Server name
• Port: PostgreSQL port number like 3306
• UserSSH: "true"
• SSHAuthMode: "Public_Key"
• SSHPort: SSH Port number
• SSHServer: SSH Server name
• SSHUser: SSH User name
• SSHClientCret: the path for the public key certificate file

Executing data movement with Logstash

Now let's run Logstash using the created "logstash.conf" file.

 logstash-7.8.0\bin\logstash -f logstash.conf

A log indicating success will appear. This means the PostgreSQL data has been loaded into Elasticsearch.

For example, let's view the data transferred to Elasticsearch in Kibana.

 GET postgresql_table/_search
 {
 "query": {
 "match_all": {}
 }
 }

We have confirmed that the data is stored in Elasticsearch.

By using the CData JDBC Driver for PostgreSQL with Logstash, it functions as a PostgreSQL connector, making it easy to load data into Elasticsearch. Please try the 30-day free trial.