Class: Tina4::Drivers::MongodbDriver

Inherits:
Object
  • Object
show all
Defined in:
lib/tina4/drivers/mongodb_driver.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#connection ⇒ Object (readonly)

Returns the value of attribute connection.



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 6

def connection
  @connection
end

#db ⇒ Object (readonly)

Returns the value of attribute db.



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 6

def db
  @db
end

Instance Method Details

#apply_limit(sql, limit, offset = 0) ⇒ Object

MongoDB has no LIMIT clause — ignore; already handled in execute_query



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 91

def apply_limit(sql, limit, offset = 0)
  sql_up = sql.upcase
  return sql if sql_up.include?("LIMIT")
  modified = sql.dup
  modified += " LIMIT #{limit}" if limit && limit > 0
  modified += " OFFSET #{offset}" if offset && offset > 0
  modified
end

#begin_transaction ⇒ Object

MongoDB transactions require a replica set — wrap in session if available



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 101

def begin_transaction
  # no-op for standalone; transaction support via session handled externally
end

#close ⇒ Object 



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 25

def close
  @client&.close
  @client = nil
  @db = nil
  @connection = nil
end

#columns(table_name) ⇒ Object 



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 117

def columns(table_name)
  collection = @db[table_name.to_s]
  sample = collection.find.limit(1).first
  return [] unless sample

  sample.keys.map do |key|
    {
      name: key,
      type: sample[key].class.name,
      nullable: true,
      default: nil,
      primary_key: key == "_id"
    }
  end
end

#commit ⇒ Object 



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 105

def commit
  # no-op
end

#connect(connection_string, username: nil, password: nil) ⇒ Object 



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 8

def connect(connection_string, username: nil, password: nil)
  begin
    require "mongo"
  rescue LoadError
    raise LoadError,
      "The 'mongo' gem is required for MongoDB connections. " \
      "Install: gem install mongo"
  end

  uri = build_uri(connection_string, username, password)
  @db_name = extract_db_name(connection_string)
  @client = Mongo::Client.new(uri)
  @db = @client.use(@db_name)
  @connection = @db
  @last_insert_id = nil
end

#execute(sql, params = []) ⇒ Object

Execute a DML statement (INSERT, UPDATE, DELETE, CREATE)



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 51

def execute(sql, params = [])
  parsed = parse_sql(sql, params)
  collection = @db[parsed[:collection]]

  case parsed[:operation]
  when :insert
    result = collection.insert_one(parsed[:document])
    @last_insert_id = result.inserted_id.to_s
    result
  when :update
    collection.update_many(parsed[:filter] || {}, { "$set" => parsed[:updates] })
  when :delete
    collection.delete_many(parsed[:filter] || {})
  when :create_collection
    begin
      @db.command(create: parsed[:collection].to_s)
    rescue Mongo::Error::OperationFailure
      # Collection already exists — ignore
    end
    nil
  when :find
    execute_query(sql, params)
  else
    nil
  end
end

#execute_query(sql, params = []) ⇒ Object

Execute a query (SELECT-like) and return array of symbol-keyed hashes



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 33

def execute_query(sql, params = [])
  parsed = parse_sql(sql, params)
  collection = @db[parsed[:collection]]

  case parsed[:operation]
  when :find
    cursor = collection.find(parsed[:filter] || {})
    cursor = cursor.projection(parsed[:projection]) if parsed[:projection] && !parsed[:projection].empty?
    cursor = cursor.sort(parsed[:sort]) if parsed[:sort] && !parsed[:sort].empty?
    cursor = cursor.skip(parsed[:skip]) if parsed[:skip] && parsed[:skip] > 0
    cursor = cursor.limit(parsed[:limit]) if parsed[:limit] && parsed[:limit] > 0
    cursor.map { |doc| mongo_doc_to_hash(doc) }
  else
    []
  end
end

#last_insert_id ⇒ Object 



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 78

def last_insert_id
  @last_insert_id
end

#placeholder ⇒ Object 



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 82

def placeholder
  "?"
end

#placeholders(count) ⇒ Object 



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 86

def placeholders(count)
  (["?"] * count).join(", ")
end

#rollback ⇒ Object 



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 109

def rollback
  # no-op
end

#tables ⇒ Object 



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 113

def tables
  @db.collection_names.reject { |n| n.start_with?("system.") }
end