Class: Cucloud::RdsUtils

Inherits:
Object
  • Object
show all
Defined in:
lib/cucloud/rds_utils.rb

Overview

RdsUtils class - for interacting with the AWS relational database service

Defined Under Namespace

Classes: RDSInstanceAlreadyExist

Instance Method Summary collapse

Constructor Details

#initialize(rds_client = Aws::RDS::Client.new) ⇒ RdsUtils

Returns a new instance of RdsUtils.



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# File 'lib/cucloud/rds_utils.rb', line 9

def initialize(rds_client = Aws::RDS::Client.new)
  @rds = rds_client
end

Instance Method Details

#create_snapshot_and_wait_until_available(rds_instance, tags = []) ⇒ Aws::RDS::DBSnapshot

Create a new snapshot of the instance, if no snapshots are already in the process of being created, and wait indefinitely until the snapshot is complete.

Parameters:

  • rds_instance (Aws::RDS::DBInstance) —

    the RDS instance which to snapshot

  • tags (Array<Hash>) (defaults to: []) —

    tags to assign to the snapshot; each array element should be of the form { key: "some key", value: "some value" }

Returns:

  • (Aws::RDS::DBSnapshot) —

    handle to the new snapshot; nil if a new snapshot cannot be created because of other pending snapshots



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# File 'lib/cucloud/rds_utils.rb', line 140

def create_snapshot_and_wait_until_available(rds_instance, tags = [])
  return nil unless pending_snapshots(rds_instance).empty?
  snap = start_snapshot(rds_instance, tags)
  wait_until_snapshot_available(snap, nil, 10)
end

#delete_db_instance(db_instance_identifier, db_snapshot_identifier = nil) ⇒ Object

Delete a givne db instance

Parameters:

  • db_instance_identifier (String) —

    RDS instance identifier

  • db_snapshot_identifier (String) (defaults to: nil) —

    Name for final snapshot, default is nil



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# File 'lib/cucloud/rds_utils.rb', line 34

def delete_db_instance(db_instance_identifier, db_snapshot_identifier = nil)
  if does_db_exist?(db_instance_identifier)
    if db_snapshot_identifier.nil?
      @rds.delete_db_instance(db_instance_identifier: db_instance_identifier, skip_final_snapshot: true)
    else
      @rds.delete_db_instance(db_instance_identifier: db_instance_identifier,
                              final_db_snapshot_identifier: db_snapshot_identifier)
    end

    @rds.wait_until(:db_instance_deleted, db_instance_identifier: db_instance_identifier)
  else
    raise Aws::RDS::Errors::DBInstanceNotFound.new(db_instance_identifier, '')
  end
end

#does_db_exist?(db_instance_identifier) ⇒ boolean

Determine if a givne db instance exist

Parameters:

  • db_instance_identifier (String) —

    RDS instance identifier

Returns:

  • (boolean) 


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# File 'lib/cucloud/rds_utils.rb', line 24

def does_db_exist?(db_instance_identifier)
  get_instance(db_instance_identifier).instance_create_time
  true
rescue Aws::RDS::Errors::DBInstanceNotFound
  false
end

#find_latest_snapshot(db_instance_identifier, snapshot_type = 'manual') ⇒ String

Delete a givne db instance

Parameters:

  • db_instance_identifier (String) —

    RDS instance identifier

Returns:

  • (String) —

    Most recent snapshot ID for given RDS instance



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# File 'lib/cucloud/rds_utils.rb', line 65

def find_latest_snapshot(db_instance_identifier, snapshot_type = 'manual')
  latest_snapshot_time = Time.new(2002)
  latest_snap_shot = nil
  snapshots_info = @rds.describe_db_snapshots(
    db_instance_identifier: db_instance_identifier, snapshot_type: snapshot_type
  )[:db_snapshots]

  snapshots_info.each do |snapshot_info|
    next if snapshot_info[:status] != 'available'

    if latest_snapshot_time.to_i < snapshot_info[:snapshot_create_time].to_i
      latest_snapshot_time = snapshot_info[:snapshot_create_time].to_i
      latest_snap_shot = snapshot_info
    end
  end

  latest_snap_shot.nil? ? nil : latest_snap_shot[:db_snapshot_identifier]
end

#get_instance(db_instance_identifier) ⇒ Aws::RDS::DBInstance

Get the RDS instance object with the given name

Parameters:

  • db_instance_identifier (String) —

    RDS instance identifier (e.g., "jadu-test-dev")

Returns:

  • (Aws::RDS::DBInstance) —

    the instance object



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# File 'lib/cucloud/rds_utils.rb', line 16

def get_instance(db_instance_identifier)
  resource = Aws::RDS::Resource.new(client: @rds)
  resource.db_instance(db_instance_identifier)
end

#pending_snapshots(rds_instance) ⇒ Collection<Aws::RDS::DBSnapshot>

Return list of pending snapshots for the instance. New snapshots cannot be created if there are any snapshots in the process of being created for the given instance.

Parameters:

  • rds_instance (Aws::RDS::DBInstance) —

    the RDS instance to examine

Returns:

  • (Collection<Aws::RDS::DBSnapshot>) —

    the collection of snapshots in the process of being created



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# File 'lib/cucloud/rds_utils.rb', line 107

def pending_snapshots(rds_instance)
  snaps = rds_instance.snapshots
  snaps.select do |snap|
    snap.status == 'creating'
  end
end

#restore_db(db_instance_identifier, restore_from, options = {}) ⇒ Object

Restore DB from a snapshot

Parameters:

  • db_instance_identifier (String) —

    RDS instance identifier

  • db_snapshot_identifier (String) —

    Name for final snapshot, default is nil

Raises:



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# File 'lib/cucloud/rds_utils.rb', line 52

def restore_db(db_instance_identifier, restore_from, options = {})
  raise RDSInstanceAlreadyExist if does_db_exist?(db_instance_identifier)

  db_snapshot_identifier =
    options[:db_snapshot_identifier].nil? ? find_latest_snapshot(restore_from) : options[:db_snapshot_identifier]
  options[:db_instance_identifier] = db_instance_identifier
  options[:db_snapshot_identifier] = db_snapshot_identifier
  @rds.restore_db_instance_from_db_snapshot(options)
end

#start_snapshot(rds_instance, tags = []) ⇒ Aws::RDS::DBSnapshot

Begins the creation of a snapshot of the given RDS instance. This is a non-blocking call so it will return before the snapshot is created and available.

Parameters:

  • rds_instance (Aws::RDS::DBInstance) —

    the RDS instance which to snapshot

  • tags (Array<Hash>) (defaults to: []) —

    tags to assign to the snapshot; each array element should be of the form { key: "some key", value: "some value" }

Returns:

  • (Aws::RDS::DBSnapshot) —

    handle to the new snapshot



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# File 'lib/cucloud/rds_utils.rb', line 91

def start_snapshot(rds_instance, tags = [])
  date = Time.new
  snap_id = rds_instance.db_instance_identifier + '-' + date.year.to_s + '-' \
      + zerofill2(date.month) + '-' + zerofill2(date.day) + '-' \
      + zerofill2(date.hour) + '-' + zerofill2(date.min)
  rds_instance.create_snapshot(
    db_snapshot_identifier:  snap_id,
    tags: tags
  )
end

#wait_until_snapshot_available(snapshot, max_attempts = nil, delay = 10) ⇒ Aws::RDS::DBSnapshot

Wait for the completion and availability of a snapshot.

Parameters:

  • snapshot (Aws::RDS::DBSnapshot) —

    the snapshot of interest

  • max_attempts (Integer) (defaults to: nil) —

    (optional) maximum number of times to poll the snapshot for status updates; defaults to nil which polls indefinitely

  • delay (Integer) (defaults to: 10) —

    (optional) number of seconds to delay between polling; defaults to 10

Returns:

  • (Aws::RDS::DBSnapshot) —

    snapshot with updated attributes; returns nil if the snapshot did not complete within the allowed time.



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# File 'lib/cucloud/rds_utils.rb', line 122

def wait_until_snapshot_available(snapshot, max_attempts = nil, delay = 10)
  snapshot.wait_until(max_attempts: max_attempts, delay: delay) do |snap|
    # Status == available is a conservative test for completion.
    # A more liberal test would be percent_progress == 100.
    snap.status == 'available'
  end
rescue Aws::Waiters::Errors::WaiterFailed
  nil
end