generator-jhipster-cassandra

A JHipster blueprint for Cassandra with advanced support for composite primary keys, sets, and maps.

Introduction

This is a JHipster blueprint designed to extend JHipster’s capabilities to support Apache Cassandra, particularly with composite primary keys, SET, and MAP types.

The generator-jhipster-cassandra blueprint provides powerful schema modeling tools tailored for Cassandra, including fine-grained control over partition and clustering keys, along with native support for complex Cassandra collections like sets and maps.

🔑 Key Features

• Composite Primary Key Support

  • Define entities with multiple primary key fields.
  • Use @customAnnotation("PrimaryKeyType.PARTITIONED") and @customAnnotation("PrimaryKeyType.CLUSTERED") to clearly specify partition and clustering columns.
  • Auto-generate query methods for equality, range, and filtering on clustering columns.

• Set & Map Field Support

  • Native Cassandra collection types are now fully supported:
    • CassandraType.Name.SET
      • Supports TEXT
    • CassandraType.Name.MAP
      • Supports various key-value types: TEXT, BOOLEAN, DECIMAL, and BIGINT.

• Custom Annotations

  • Annotations like @customAnnotation("UTC_DATE") or @customAnnotation("TIMEUUID") support consistent metadata across entity fields.

• Optimized for Microservices

  • Seamless integration with the JHipster microservice architecture.
  • Supports JDL files with complex schemas.

🧑‍💻 Example Use Cases

• Model a Post entity using a composite primary key (createdDate, addedDateTime, postId) and additional attributes like title and content.
• Use SET to tag entities with multiple string values.
• Use MAP to represent dynamic metadata or key-value configurations (e.g., addOnDetailsBoolean, addOnDetailsDecimal).

🧪 JDL Examples

Composite Key Example

Below are various examples of defining JDL entities using the @customAnnotation methodology to specify the details of the Cassandra composite primary key. Also, below is an example of a single-value primary key entity. Some example entities are of composite primary keys using Map fields and some are using a Set field. There are also examples of single-value primary key entities using Maps and Set data structures.

    // Composite Primary Key Example:
    entity Post {
      @Id @customAnnotation("PrimaryKeyType.PARTITIONED") @customAnnotation("CassandraType.Name.BIGINT") @customAnnotation("UTC_DATE") @customAnnotation("0") createdDate Long 
      // Do not name composite primary key fields as 'id' as it conflicts with the 'id' field in the JHipster entity.
      @customAnnotation("PrimaryKeyType.CLUSTERED") @customAnnotation("CassandraType.Name.BIGINT") @customAnnotation("UTC_DATETIME") @customAnnotation("1") addedDateTime Long
      @customAnnotation("PrimaryKeyType.CLUSTERED") @customAnnotation("CassandraType.Name.UUID") @customAnnotation("") @customAnnotation("2") postId UUID
      @customAnnotation("") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") @customAnnotation("") title String required
      @customAnnotation("") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") @customAnnotation("") content String required
      @customAnnotation("") @customAnnotation("CassandraType.Name.BIGINT") @customAnnotation("UTC_DATETIME") @customAnnotation("") publishedDateTime Long
      @customAnnotation("") @customAnnotation("CassandraType.Name.BIGINT") @customAnnotation("UTC_DATE") @customAnnotation("") sentDate Long
    }

    // Single-value Primary Key Example:
    entity Product {
      // Primary Key field can be named 'id'.  JHipster natively supports single-value primary keys.  This blueprint also supports single-value primary keys.
      @Id @customAnnotation("PrimaryKeyType.PARTITIONED") @customAnnotation("CassandraType.Name.UUID") @customAnnotation("") @customAnnotation("") id UUID
      @customAnnotation("") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") @customAnnotation("") title String required
      @customAnnotation("") @customAnnotation("CassandraType.Name.DECIMAL") @customAnnotation("") @customAnnotation("") price BigDecimal required min(0)
      @customAnnotation("") @customAnnotation("CassandraType.Name.BLOB") @customAnnotation("image") @customAnnotation("") image ImageBlob
      @customAnnotation("") @customAnnotation("CassandraType.Name.BIGINT") @customAnnotation("UTC_DATE") @customAnnotation("") addedDate Long required
    }

    // Composite Primary Key Example with TIMEUUID clustered key, multiple partitioned keys, with multiple clustered keys.
    entity SaathratriEntity2 {
      @Id @customAnnotation("PrimaryKeyType.PARTITIONED") @customAnnotation("CassandraType.Name.UUID") @customAnnotation("") entityTypeId UUID
      @customAnnotation("PrimaryKeyType.PARTITIONED") @customAnnotation("CassandraType.Name.BIGINT") @customAnnotation("") yearOfDateAdded Long
      @customAnnotation("PrimaryKeyType.CLUSTERED") @customAnnotation("CassandraType.Name.BIGINT") @customAnnotation("UTC_DATE") arrivalDate Long
      @customAnnotation("PrimaryKeyType.CLUSTERED") @customAnnotation("CassandraType.Name.TIMEUUID") @customAnnotation("TIMEUUID") blogId UUID
      @customAnnotation("") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") entityName String
      @customAnnotation("") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") entityDescription String
      @customAnnotation("") @customAnnotation("CassandraType.Name.DECIMAL") @customAnnotation("") entityCost BigDecimal
      @customAnnotation("") @customAnnotation("CassandraType.Name.BIGINT") @customAnnotation("UTC_DATE") departureDate Long
    }

    // Example showing a text/string set.
    entity SaathratriEntity3 {
      @Id @customAnnotation("PrimaryKeyType.PARTITIONED") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") entityType String
      @customAnnotation("PrimaryKeyType.CLUSTERED") @customAnnotation("CassandraType.Name.TIMEUUID") @customAnnotation("") createdTimeId UUID
      @customAnnotation("") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") entityName String
      @customAnnotation("") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") entityDescription String
      @customAnnotation("") @customAnnotation("CassandraType.Name.DECIMAL") @customAnnotation("") entityCost BigDecimal
      @customAnnotation("") @customAnnotation("CassandraType.Name.BIGINT") @customAnnotation("UTC_DATE") departureDate Long
      @customAnnotation("CassandraType.Name.SET") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") tags String,
    }

    // Example showing key-value data structure.
    entity SaathratriEntity4 {
      @Id @customAnnotation("PrimaryKeyType.PARTITIONED") @customAnnotation("CassandraType.Name.UUID") @customAnnotation("") organizationId UUID
      @customAnnotation("PrimaryKeyType.CLUSTERED") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") attributeKey String
      @customAnnotation("") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") attributeValue String
    }

        // Example showing text/string, boolean, numeric and date-time maps.
    entity AddOnsAvailableByOrganization {
      @Id @customAnnotation("PrimaryKeyType.PARTITIONED") @customAnnotation("CassandraType.Name.UUID") @customAnnotation("") organizationId UUID
      @customAnnotation("PrimaryKeyType.PARTITIONED") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") entityType String
      @customAnnotation("PrimaryKeyType.PARTITIONED") @customAnnotation("CassandraType.Name.UUID") @customAnnotation("") entityId UUID
      @customAnnotation("PrimaryKeyType.CLUSTERED") @customAnnotation("CassandraType.Name.UUID") @customAnnotation("") addOnId UUID
      @customAnnotation("") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") addOnType String
      @customAnnotation("CassandraType.Name.MAP") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") addOnDetailsText String
      @customAnnotation("CassandraType.Name.MAP") @customAnnotation("CassandraType.Name.DECIMAL") @customAnnotation("") addOnDetailsDecimal BigDecimal
      @customAnnotation("CassandraType.Name.MAP") @customAnnotation("CassandraType.Name.BOOLEAN") @customAnnotation("") addOnDetailsBoolean Boolean
      @customAnnotation("CassandraType.Name.MAP") @customAnnotation("CassandraType.Name.BIGINT") @customAnnotation("UTC_DATETIME") addOnDetailsBigInt Long
    }

    // Another example showing text/string, boolean, numeric and date-time maps.
    entity AddOnsSelectedByOrganization {
      @Id @customAnnotation("PrimaryKeyType.PARTITIONED") @customAnnotation("CassandraType.Name.UUID") @customAnnotation("") organizationId UUID
      @customAnnotation("PrimaryKeyType.CLUSTERED") @customAnnotation("CassandraType.Name.BIGINT") @customAnnotation("UTC_DATE") arrivalDate Long
      @customAnnotation("PrimaryKeyType.CLUSTERED") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") accountNumber String
      @customAnnotation("PrimaryKeyType.CLUSTERED") @customAnnotation("CassandraType.Name.TIMEUUID") @customAnnotation("") createdTimeId UUID
      @customAnnotation("") @customAnnotation("CassandraType.Name.BIGINT") @customAnnotation("UTC_DATE") departureDate Long
      @customAnnotation("") @customAnnotation("CassandraType.Name.UUID") @customAnnotation("") customerId UUID
      @customAnnotation("") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") customerFirstName String
      @customAnnotation("") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") customerLastName String
      @customAnnotation("") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") customerUpdatedEmail String
      @customAnnotation("") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") customerUpdatedPhoneNumber String
      @customAnnotation("") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") customerEstimatedArrivalTime String
      @customAnnotation("") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") tinyUrlShortCode String
      @customAnnotation("CassandraType.Name.MAP") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") addOnDetailsText String
      @customAnnotation("CassandraType.Name.MAP") @customAnnotation("CassandraType.Name.DECIMAL") @customAnnotation("") addOnDetailsDecimal BigDecimal
      @customAnnotation("CassandraType.Name.MAP") @customAnnotation("CassandraType.Name.BOOLEAN") @customAnnotation("") addOnDetailsBoolean Boolean
      @customAnnotation("CassandraType.Name.MAP") @customAnnotation("CassandraType.Name.BIGINT") @customAnnotation("UTC_DATETIME") addOnDetailsBigInt Long
    }

    // Single-value Primary Key with Maps
    entity LandingPageByOrganization {
      @Id @customAnnotation("PrimaryKeyType.PARTITIONED") @customAnnotation("CassandraType.Name.UUID") @customAnnotation("") organizationId UUID
      @customAnnotation("CassandraType.Name.MAP") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") detailsText String
      @customAnnotation("CassandraType.Name.MAP") @customAnnotation("CassandraType.Name.DECIMAL") @customAnnotation("") detailsDecimal BigDecimal
      @customAnnotation("CassandraType.Name.MAP") @customAnnotation("CassandraType.Name.BOOLEAN") @customAnnotation("") detailsBoolean Boolean
      @customAnnotation("CassandraType.Name.MAP") @customAnnotation("CassandraType.Name.BIGINT") @customAnnotation("UTC_DATETIME") detailsBigInt Long
    }

    // Single-value Primary Key with Set
    entity SetEntityByOrganization {
      @Id @customAnnotation("PrimaryKeyType.PARTITIONED") @customAnnotation("CassandraType.Name.UUID") @customAnnotation("") organizationId UUID
      @customAnnotation("CassandraType.Name.SET") @customAnnotation("CassandraType.Name.TEXT") @customAnnotation("") tags String
    }

🚀 Quick Start

Prerequisites

• Java 21+
• Node.js 20+
• Docker Desktop
• JHipster 8.6.0+

Installation

npm install -g generator-jhipster-cassandra

Usage

jhipster --blueprints cassandra

🎡 Example Project

• Full example repo with Cassandra composite key entities and JDL: 👉 https://github.com/amarpatel-xx/jhipster-cassandra-example

Generate Code

git clone https://github.com/amarpatel-xx/jhipster-cassandra-example.git
cd jhipster-cassandra-example
sh saathratri-generate-code-dev-cassandra.sh

🔐 Identity Providers

This blueprint supports Keycloak by default. You can switch to Okta using:

okta apps create jhipster

🧐 Learn More

• 📘 Cassandra Data Modeling
• 📘 JHipster Blueprints
• 🧓 Matt Raible on Micro Frontends

👏 Acknowledgements

Huge thanks to:

• yelhouti
• Jeremy Artero
• Matt Raible
• Gaël Marziou
• Cedrick Lunven
• Christophe Borne
• Disha Patel
• Catherine Guevara