Why templates standardize index creation in Elasticsearch - See It in Action

Why templates standardize index creation

📖 Scenario: You work in a company that collects logs from many servers. Each day, a new index is created to store that day's logs. To keep the data organized and consistent, you want to use a template that sets the rules for all daily log indexes.

🎯 Goal: Create an Elasticsearch index template that standardizes the creation of daily log indexes with consistent settings and mappings.

📋 What You'll Learn

Create an index template named daily_logs_template

Set the template to apply to index names starting with logs-

Define settings with number_of_shards set to 1

Define mappings with a timestamp field of type date

Define mappings with a message field of type text

💡 Why This Matters

🌍 Real World

Companies use index templates to manage large volumes of log or event data that arrive daily, ensuring all indexes have the same structure and performance settings.

💼 Career

Knowing how to create and use index templates is important for roles like DevOps engineers, data engineers, and anyone managing Elasticsearch clusters to maintain data consistency and optimize search performance.

1

Create the basic index template structure

Create a variable called daily_logs_template and assign it a dictionary with keys index_patterns set to a list containing "logs-*", and an empty template dictionary.

Elasticsearch

daily_logs_template = {
    "index_patterns": ["logs-*"] ,
    "template": {}
}
# Your code here

Need a hint?

Start by creating a dictionary with the keys index_patterns and template.

2

Add settings to the template

Inside the template dictionary of daily_logs_template, add a settings dictionary with number_of_shards set to 1.

Elasticsearch

daily_logs_template = {
    "index_patterns": ["logs-*"] ,
    "template": {
        "settings": {
            # Your code here
        }
    }
}

Need a hint?

Settings control how the index stores data. Use number_of_shards to set the number of pieces the index is split into.

3

Add mappings for fields

Inside the template dictionary of daily_logs_template, add a mappings dictionary with properties defining a timestamp field of type date and a message field of type text.

Elasticsearch

daily_logs_template = {
    "index_patterns": ["logs-*"] ,
    "template": {
        "settings": {
            "number_of_shards": 1
        },
        "mappings": {
            "properties": {
                # Your code here
            }
        }
    }
}

Need a hint?

Mappings define the data types of fields in the index. Use properties to list fields and their types.

4

Complete the template for use

Ensure the daily_logs_template dictionary includes index_patterns, template with settings and mappings as defined, ready to be used to create indexes.

Elasticsearch

daily_logs_template = {
    "index_patterns": ["logs-*"] ,
    "template": {
        "settings": {
            "number_of_shards": 1
        },
        "mappings": {
            "properties": {
                "timestamp": {"type": "date"},
                "message": {"type": "text"}
            }
        }
    }
}
# Your code here

Need a hint?

Review the full template dictionary to confirm all parts are included.