Class: Moneta::Adapters::Sqlite
- Inherits:
-
Object
- Object
- Moneta::Adapters::Sqlite
- Includes:
- Defaults, IncrementSupport
- Defined in:
- lib/moneta/adapters/sqlite.rb
Overview
Sqlite3 backend
Instance Attribute Summary collapse
- #backend ⇒ Object readonly
Instance Method Summary collapse
-
#clear(options = {}) ⇒ void
Clear all keys in this store.
-
#close ⇒ Object
Explicitly close the store.
- #create(key, value, options = {}) ⇒ Object
-
#delete(key, options = {}) ⇒ Object
Delete the key from the store and return the current value.
-
#increment(key, amount = 1, options = {}) ⇒ Object
Atomically increment integer value with key.
-
#initialize(options = {}) ⇒ Sqlite
constructor
A new instance of Sqlite.
-
#key?(key, options = {}) ⇒ Boolean
Exists the value with key.
-
#load(key, options = {}) ⇒ Object
Fetch value with key.
-
#store(key, value, options = {}) ⇒ Object
Store value with key.
Methods included from IncrementSupport
Methods included from Defaults
#[], #[]=, #decrement, #features, #fetch, included, #supports?
Methods included from OptionSupport
#expires, #prefix, #raw, #with
Constructor Details
#initialize(options = {}) ⇒ Sqlite
Returns a new instance of Sqlite.
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# File 'lib/moneta/adapters/sqlite.rb', line 19 def initialize( = {}) table = [:table] || 'moneta' @backend = [:backend] || begin raise ArgumentError, 'Option :file is required' unless [:file] ::SQLite3::Database.new([:file]) end @backend.busy_timeout([:busy_timeout] || 1000) @backend.execute("create table if not exists #{table} (k blob not null primary key, v blob)") @stmts = [@select = @backend.prepare("select v from #{table} where k = ?"), @replace = @backend.prepare("replace into #{table} values (?, ?)"), @delete = @backend.prepare("delete from #{table} where k = ?"), @clear = @backend.prepare("delete from #{table}"), @create = @backend.prepare("insert into #{table} values (?, ?)")] end |
Instance Attribute Details
#backend ⇒ Object (readonly)
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# File 'lib/moneta/adapters/sqlite.rb', line 12 def backend @backend end |
Instance Method Details
#clear(options = {}) ⇒ void
This method returns an undefined value.
Clear all keys in this store
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# File 'lib/moneta/adapters/sqlite.rb', line 66 def clear( = {}) @clear.execute! self end |
#close ⇒ Object
Explicitly close the store
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# File 'lib/moneta/adapters/sqlite.rb', line 83 def close @stmts.each {|s| s.close } @backend.close nil end |
#create(key, value, options = {}) ⇒ Object
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# File 'lib/moneta/adapters/sqlite.rb', line 72 def create(key, value, = {}) @create.execute!(key,value) true rescue SQLite3::ConstraintException # If you know a better way to detect whether an insert-ignore # suceeded, please tell me. @create.reset! false end |
#delete(key, options = {}) ⇒ Object
Delete the key from the store and return the current value
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# File 'lib/moneta/adapters/sqlite.rb', line 54 def delete(key, = {}) value = load(key, ) @delete.execute!(key) value end |
#increment(key, amount = 1, options = {}) ⇒ Object
Not every Moneta store implements this method, a NotImplementedError is raised if it is not supported.
Atomically increment integer value with key
This method also accepts negative amounts.
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# File 'lib/moneta/adapters/sqlite.rb', line 61 def increment(key, amount = 1, = {}) @backend.transaction(:exclusive) { return super } end |
#key?(key, options = {}) ⇒ Boolean
Exists the value with key
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# File 'lib/moneta/adapters/sqlite.rb', line 37 def key?(key, = {}) !@select.execute!(key).empty? end |
#load(key, options = {}) ⇒ Object
Fetch value with key. Return nil if the key doesn’t exist
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# File 'lib/moneta/adapters/sqlite.rb', line 42 def load(key, = {}) rows = @select.execute!(key) rows.empty? ? nil : rows.first.first end |
#store(key, value, options = {}) ⇒ Object
Store value with key
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# File 'lib/moneta/adapters/sqlite.rb', line 48 def store(key, value, = {}) @replace.execute!(key, value) value end |