Class: Karafka::Web::Pro::Ui::Controllers::Topics::ReplicationsController

Inherits:
BaseController show all
Defined in:
lib/karafka/web/pro/ui/controllers/topics/replications_controller.rb

Overview

Controller responsible for viewing and managing topics replication details

Constant Summary

Constants inherited from Ui::Controllers::BaseController

Ui::Controllers::BaseController::Models

Instance Attribute Summary

Attributes inherited from Ui::Controllers::BaseController

#params, #session

Instance Method Summary collapse

Methods inherited from Ui::Controllers::BaseController

#cache, #initialize

Methods included from Ui::Controllers::Requests::Hookable

included, #run_after_hooks, #run_before_hooks

Constructor Details

This class inherits a constructor from Karafka::Web::Ui::Controllers::BaseController

Instance Method Details

#show(topic_name) ⇒ Object

Displays requested topic replication details

Parameters:

  • topic_name (String)

    topic we’re interested in



49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
# File 'lib/karafka/web/pro/ui/controllers/topics/replications_controller.rb', line 49

def show(topic_name)
  @topic = Models::Topic.find(topic_name)

  @partitions = refine(@topic[:partitions])

  # Extract replication factor from the first partition (same for all partitions)
  # The partitions data is an array of hashes with :replica_count key
  first_partition = @topic[:partitions]&.first
  @replication_factor = first_partition&.fetch(:replica_count, 0) || 0

  # Fetch min.insync.replicas from topic config
  min_isr_config = @topic.configs.find { |c| c.name == "min.insync.replicas" }
  @min_isr = min_isr_config&.value&.to_i || 1

  # Determine resilience issues (checked in priority order):
  # 1. No redundancy: RF = 1 (single point of failure, most severe)
  # 2. Zero write fault tolerance: RF > 1 but RF <= minISR (can't lose any broker)
  # 3. Low durability: RF > 1 and minISR = 1 (data loss risk if leader fails)
  @has_no_redundancy = @replication_factor == 1
  @has_zero_fault_tolerance = @replication_factor > 1 &&
    @replication_factor <= @min_isr
  @has_low_durability = @replication_factor > 1 && @min_isr == 1

  @has_resilience_issue = @has_zero_fault_tolerance ||
    @has_low_durability ||
    @has_no_redundancy

  render
end