ConnectionLifeguard NPM Library

Overview

ConnectionLifeguard is used to determine when a client is allowed to obtain a connection with a database. This library is used in conjunction with the oraclelib layer.

See also ABOUT

Configuring your lambda's serverless.yml for use with ConnectionLifeguard

Before you can make use of ConnectionLifeguard, you'll need to give your lambda appropriate permission.

provider:
  environment:
    ACCOUNT_ID: '#{AWS::AccountId}'
    TABLE_COUNTER: ConnectionLifeguardCounter
    TABLE_UUID: ConnectionLifeguardUuid
    QNAME: ConnectionLifeguard
  iamRoleStatements:
    - Effect: Allow
      Action: # Gives permission to DynamoDB tables in a specific region
        - dynamodb:Query
        - dynamodb:Scan
        - dynamodb:GetItem
        - dynamodb:PutItem
        - dynamodb:UpdateItem
        - dynamodb:DeleteItem
      Resource: "arn:aws:dynamodb:${self:provider.region}:*:table/${self:provider.environment.TABLE_COUNTER}*"
    - Effect: Allow
      Action: # Gives permission to DynamoDB tables in a specific region
        - dynamodb:Query
        - dynamodb:Scan
        - dynamodb:GetItem
        - dynamodb:PutItem
        - dynamodb:UpdateItem
        - dynamodb:DeleteItem
      Resource: "arn:aws:dynamodb:${self:provider.region}:*:table/${self:provider.environment.TABLE_UUID}*"
    - Effect: "Allow"
      Action:
        - "sqs:SendMessage"
        - "sqs:GetQueueUrl"
      Resource: "arn:aws:sqs:${self:provider.region}:*:${self:provider.environment.QNAME}*"

Example Usage

const {requestApproval, done} = require('@nuskin/connection-lifeguard')

const main = async () => {
  const pool = 'poolName'
  let uuid
  let approved
  try {
    let count = 0
    do {
      count++
      const response = await requestApproval(pool)
      approved = response.approved
      if(approved){
        uuid = response.uuid
        // you're allowed to get a db connection now.
        // do your processing here onse.data.uuid
      }
    } while(!approved && count<4) // attempt to get approval 4 times
  } catch(error) {
      console.error("We got an error: ",error)
  } finally {
    // Close your connection with the database here.
    // Tell the connection lifeguard you have closed your connection.
    await done(pool, uuid)
  }
}

main()

Example Response

{
  "approved": true,
  "count": 7,
  "uuid": "N3ZCSMAUs2DGs1PA2ItxxX"
}

Resources

• SDK Documentation

License

MIT