Loopback - Create datasource and model for Cassandra

Loopback 3.0- Create datasource and model for Cassandra

Pre-Installed:-

                          Loopback 3.0 and cassandra 

Step 1: Creating a Keyspace using Cqlsh

cqlsh.> CREATE KEYSPACE test
WITH replication = {'class':'SimpleStrategy', 'replication_factor' : 3};

cqlsh> DESCRIBE keyspaces;

test system system_traces 

Step 2: Creating a table using Cqlsh

cqlsh> USE test;

cqlsh:test>; CREATE TABLE pullcassandra(
   id text PRIMARY KEY
   emp_id text,
   emp_name text,
   emp_city text,
   emp_sal text,
   emp_phone text,
   );

"id" - for store the object key which is generated by loopback

 Step 3: Creating a datasouce

In your application root directory, enter this command to install the connector:

npm install loopback-connector-cassandra --save

$ lb datasource
? Enter the data-source name: mycass
? Select the connector for mycass: Cassandra (supported by StrongLoop)
Connector-specific configuration:
? host: localhost
? port: 9042
? user: 
? password: 
? database: test
? connectTimeout(ms): 30000
? readTimeout(ms): 30000
? Install loopback-connector-cassandra@^1.0.0 Yes
loopback-connector-cassandra@1.0.0 node_modules/loopback-connector-cassandra
...

The entry in the application’s /server/datasources.json will look like this:

"mycass": {
  "host": "localhost",
  "port": 9042,
  "database": "test",
  "password": "",
  "name": "mycass",
  "user": "",
  "connectTimeout": 30000,
  "readTimeout": 30000,
  "connector": "cassandra"
}

Step 4: Creating a model

$ lb model
? Enter the model name: pullcassandra
? Select the datasource to attach pullcassandra to: cassandra (cassandra)
? Select model's base class PersistedModel
? Expose pullcassandra via the REST API? No
? Common model or server only? common
Let's add some pullcassandra properties now.

Enter an empty property name when done.
? Property name: emp_id
   invoke   loopback:property
? Property type: string
? Required? Yes
? Default value[leave blank for none]: 

Let's add another pullcassandra property.
Enter an empty property name when done.
? Property name: emp_city
   invoke   loopback:property
? Property type: string
? Required? Yes
? Default value[leave blank for none]: 

Let's add another pullcassandra property.
Enter an empty property name when done.
? Property name: emp_name
   invoke   loopback:property
? Property type: string
? Required? Yes
? Default value[leave blank for none]: 

Let's add another pullcassandra property.
Enter an empty property name when done.
? Property name: emp_phone
   invoke   loopback:property
? Property type: string
? Required? Yes
? Default value[leave blank for none]: 

Let's add another pullcassandra property.
Enter an empty property name when done.
? Property name: emp_sal
   invoke   loopback:property
? Property type: string
? Required? Yes
? Default value[leave blank for none]: 

Let's add another pullcassandra property.
Enter an empty property name when done.
? Property name: 

The entry in the application’s /models/pullcassandra.json will look like this:

{
  "name": "pullcassandra",
  "base": "PersistedModel",
  "idInjection": true,
  "options": {
    "validateUpsert": true
  },
  "properties": {
    "emp_id": {
      "type": "string",
      "required": true
    },
    "emp_city": {
      "type": "string",
      "required": true
    },
    "emp_name": {
      "type": "string",
      "required": true
    },
    "emp_phone": {
      "type": "string",
      "required": true
    },
    "emp_sal": {
      "type": "string",
      "required": true
    }
  },
  "validations": [],
  "relations": {},
  "acls": [],
  "methods": {}
}

Step 5: Start Your Application

$ node .

Output:-

Use https://localhost:3000/explorer to check in client

Thats it!.......... Thank you..