Dynamic templates in Elasticsearch - Mini Project: Build & Apply

Dynamic templates

📖 Scenario: You are setting up an Elasticsearch index to store product information. You want to automatically map fields that contain text to use a keyword type for exact matching, and fields that contain numbers to use a long type.

🎯 Goal: Create an Elasticsearch index with dynamic templates that automatically assign the keyword type to text fields and the long type to numeric fields.

📋 What You'll Learn

Create an index mapping with a dynamic_templates array

Add a dynamic template named strings_as_keywords that matches fields of type string and maps them as keyword

Add a dynamic template named numbers_as_long that matches fields of type long and maps them as long

Print the final mapping JSON

💡 Why This Matters

🌍 Real World

Dynamic templates are used in Elasticsearch to simplify index mappings by automatically assigning field types based on data patterns. This saves time and reduces errors when indexing diverse data.

💼 Career

Understanding dynamic templates is important for roles involving search engine setup, data indexing, and backend development where Elasticsearch is used to manage large datasets efficiently.

1

Create the initial index mapping with empty dynamic_templates

Create a variable called mapping and assign it a dictionary with a mappings key containing an empty dynamic_templates list.

Elasticsearch

mapping = {
    "mappings": {
        "dynamic_templates": []
    }
}
# Your code here

Need a hint?

Use a dictionary with keys mappings and inside it dynamic_templates as an empty list.

2

Add a dynamic template for string fields as keyword

Add a dictionary to mapping["mappings"]["dynamic_templates"] with a template named strings_as_keywords that matches fields of type string and maps them as keyword type.

Elasticsearch

mapping = {
    "mappings": {
        "dynamic_templates": []
    }
}
# Add dynamic template for strings_as_keywords here

Need a hint?

Use a dictionary with keys strings_as_keywords, match_mapping_type set to string, and mapping with type set to keyword.

3

Add a dynamic template for numeric fields as long

Add another dictionary to mapping["mappings"]["dynamic_templates"] with a template named numbers_as_long that matches fields of type long and maps them as long type.

Elasticsearch

mapping = {
    "mappings": {
        "dynamic_templates": [
            {
                "strings_as_keywords": {
                    "match_mapping_type": "string",
                    "mapping": {
                        "type": "keyword"
                    }
                }
            }
        ]
    }
}
# Add dynamic template for numbers_as_long here

Need a hint?

Add a dictionary similar to the string template but with match_mapping_type as long and type as long.

4

Print the final mapping JSON

Use print(mapping) to display the final mapping dictionary.

Elasticsearch

mapping = {
    "mappings": {
        "dynamic_templates": [
            {
                "strings_as_keywords": {
                    "match_mapping_type": "string",
                    "mapping": {
                        "type": "keyword"
                    }
                }
            },
            {
                "numbers_as_long": {
                    "match_mapping_type": "long",
                    "mapping": {
                        "type": "long"
                    }
                }
            }
        ]
    }
}
# Print the mapping dictionary below

Need a hint?

Use print(mapping) to show the dictionary.