ConfigSection¶

Hash-like wrapper for nested configuration with method access and Enumerable support.

Overview¶

ConfigSection wraps Hash values from YAML, providing:

Method access (config.database.host)
Bracket access (config.database[:host])
Enumerable iteration
Hash-like methods (keys, values, fetch, dig)

Constructor¶

new¶

Create a new ConfigSection from a Hash.

section = MywayConfig::ConfigSection.new(host: "localhost", port: 5432)

Parameters:

hash (Hash) - The hash to wrap (default: {})

Behavior:

Keys are symbolized
Nested Hashes become nested ConfigSections

Access Methods¶

Method Access¶

section.host        # => "localhost"
section.port        # => 5432
section.missing     # => nil

Bracket Access¶

section[:host]      # => "localhost"
section["host"]     # => "localhost"

Setting Values¶

section.host = "new-host"
section[:port] = 5433

Hash Methods¶

keys¶

Get all keys.

section.keys  # => [:host, :port, :name]

Returns:

Array<Symbol> - All keys

values¶

Get all values.

section.values  # => ["localhost", 5432, "myapp_db"]

Returns:

Array - All values

size / length¶

Get the number of keys.

section.size    # => 3
section.length  # => 3

Returns:

Integer - Number of keys

key? / has_key? / include? / member?¶

Check if a key exists.

section.key?(:host)       # => true
section.has_key?(:host)   # => true
section.include?(:host)   # => true
section.member?(:host)    # => true

Parameters:

key (Symbol, String) - The key to check

Returns:

Boolean - true if key exists

empty?¶

Check if the section has no keys.

section.empty?  # => false
MywayConfig::ConfigSection.new.empty?  # => true

Returns:

Boolean - true if no keys

fetch¶

Fetch a value with optional default.

# With key
section.fetch(:host)  # => "localhost"

# With default value
section.fetch(:missing, "default")  # => "default"

# With block
section.fetch(:missing) { |k| "no #{k}" }  # => "no missing"

# Without default (raises KeyError)
section.fetch(:missing)  # => KeyError: key not found: :missing

Parameters:

key (Symbol, String) - The key to fetch
default (Object) - Optional default value

Yields:

key - When block provided and key missing

Returns:

Object - The value or default

Raises:

KeyError - If key not found and no default

dig¶

Access nested values safely.

config.api.dig(:headers, :content_type)  # => "application/json"
config.api.dig(:missing, :nested)        # => nil

Parameters:

keys (Array) - Keys to dig through

Returns:

Object, nil - The value or nil if not found

[] and []=¶

Bracket access and assignment.

section[:host]        # => "localhost"
section[:host] = "new-host"

Enumerable Methods¶

ConfigSection includes Enumerable, providing all iteration methods.

each¶

Iterate over key-value pairs.

section.each do |key, value|
  puts "#{key}: #{value}"
end

map¶

Transform key-value pairs.

section.map { |k, v| "#{k}=#{v}" }
# => ["host=localhost", "port=5432"]

select / reject¶

Filter key-value pairs.

section.select { |k, v| v.is_a?(Integer) }
# => [[:port, 5432], [:pool, 5]]

section.reject { |k, v| v.nil? }

find / detect¶

Find first matching pair.

section.find { |k, v| v == 5432 }
# => [:port, 5432]

any? / all? / none?¶

Check conditions.

section.any? { |k, v| v.nil? }   # => false
section.all? { |k, v| v }        # => true
section.none? { |k, v| v.nil? }  # => true

Other Enumerable Methods¶

All standard Enumerable methods work:

count, first, take, drop
min, max, minmax
sort, sort_by
group_by, partition
reduce, inject
And more...

Conversion Methods¶

to_h¶

Convert to a plain Ruby Hash.

section.to_h
# => {host: "localhost", port: 5432, name: "myapp_db"}

Nested ConfigSections are also converted:

config.api.to_h
# => {
#      base_url: "https://api.example.com",
#      timeout: 30,
#      headers: {content_type: "application/json"}
#    }

Returns:

Hash - Plain Ruby Hash

merge¶

Merge with another ConfigSection or Hash.

overrides = { host: "new-host", pool: 10 }
merged = section.merge(overrides)

merged.host  # => "new-host"
merged.pool  # => 10
merged.port  # => 5432 (from original)

Parameters:

other (ConfigSection, Hash) - Values to merge

Returns:

ConfigSection - New merged ConfigSection

Examples¶

Building Connection Strings¶

db = config.database
connection_string = "postgres://#{db.host}:#{db.port}/#{db.name}"
# => "postgres://localhost:5432/myapp_db"

Filtering Configuration¶

# Get all non-nil settings
config.database.reject { |k, v| v.nil? }.to_h

Transforming Values¶

# Upcase all string values
config.database.map { |k, v|
  [k, v.is_a?(String) ? v.upcase : v]
}.to_h

Safe Nested Access¶

# Won't raise even if path doesn't exist
timeout = config.api.dig(:retry, :timeout) || 30