Class: Tina4::Drivers::MongodbDriver

Inherits:
Object
  • Object
show all
Includes:
Tina4::DatabaseAdapter
Defined in:
lib/tina4/drivers/mongodb_driver.rb

Constant Summary

Constants included from Tina4::DatabaseAdapter

Tina4::DatabaseAdapter::ABSTRACT_CONTRACT, Tina4::DatabaseAdapter::CONNECT_TIMEOUT_SLACK_SECONDS, Tina4::DatabaseAdapter::CONNECT_TIMEOUT_VAR, Tina4::DatabaseAdapter::CONTRACT, Tina4::DatabaseAdapter::DEFAULT_CONNECT_TIMEOUT_SECONDS

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Tina4::DatabaseAdapter

#autocommit, #autocommit=, bounding_connect, connect_timed_out!, connect_timeout_seconds, connect_timeout_whole_seconds, #execute_many, #fetch, #fetch_one, implemented_by?, #open, #start_transaction, #supports_atomic_batch, #supports_atomic_batch=, #table_exists?, validate!

Instance Attribute Details

#connection ⇒ Object (readonly)

Returns the value of attribute connection.



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 7

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 7

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 Uses the SAME detector as Database#fetch (scrubbed + anchored to the end) instead of its own naive sql.upcase.include?("LIMIT"), which mistook a column named rate_limit or a 'LIMIT' literal for a real clause and returned the statement uncapped. Appends on a NEW LINE so a trailing -- comment cannot swallow the clause.



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 153

def apply_limit(sql, limit, offset = 0)
  return sql if Tina4::Database.has_trailing_limit?(sql)
  modified = sql.dup
  modified += "\nLIMIT #{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 162

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 37

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 183

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 166

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 9

def connect(connection_string, username: nil, password: nil)
  begin
    require "mongo"
  rescue LoadError
    raise LoadError,
          "The 'mongo' gem is required for MongoDB connections. Install one of:\n" \
          "    bundle add mongo     # if your project uses Bundler\n" \
          "    gem install mongo    # bare driver"
  end

  uri = build_uri(connection_string, username, password)
  @db_name = extract_db_name(connection_string)
  # The mongo driver's OWN connect_timeout, in seconds. It already bounds
  # itself - MEASURED: Mongo::Client.new against a TCPServer that accepts
  # and never replies returns after 10.02s, the gem's hard-coded default -
  # so this makes it honour the Tina4 variable instead. A URI that spells
  # connectTimeoutMS itself keeps that value. No bounding_connect wrapper:
  # Client.new does NOT raise on an unreachable server (server selection
  # happens later, on the first operation), so there is no expiry to name.
  seconds = Tina4::DatabaseAdapter.connect_timeout_seconds
  options = {}
  options[:connect_timeout] = seconds if seconds && !uri.include?("connectTimeoutMS")
  @client = Mongo::Client.new(uri, options)
  @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 63

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
    # parse_update guarantees a scoped filter (or it raised) — no || {} fallback.
    collection.update_many(parsed[:filter], { "$set" => parsed[:updates] })
  when :delete
    # parse_delete guarantees a scoped filter (or it raised) — no || {} fallback.
    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 45

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

#get_database_type ⇒ Object

ADR-0044 required adapter capability.



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 175

def get_database_type
  'mongodb'
end

#get_next_id(table, pk_column = "id") ⇒ Object

Atomic, monotonic, concurrency-safe next id — feature 16. A findOneAndUpdate($inc) on the tina4_sequences collection, keyed by _id (its built-in unique index makes concurrent first-use upserts race-safe: two callers can never create two counters for one table). Seeds from MAX(pk_column) the FIRST time only ($setOnInsert). Raises on an impossible empty result rather than returning a fixed id that could collide with an existing row.



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 103

def get_next_id(table, pk_column = "id")
  sequences = @db["tina4_sequences"]
  seq_name = "#{table}.#{pk_column}"

  if sequences.find("_id" => seq_name).first.nil?
    seed = 0
    begin
      max_doc = @db[table.to_s].find.sort(pk_column => -1).limit(1).first
      seed = max_doc[pk_column].to_i if max_doc && max_doc[pk_column]
    rescue StandardError
      # Collection may not exist yet — seed 0.
    end
    begin
      sequences.update_one(
        { "_id" => seq_name },
        { "$setOnInsert" => { "current_value" => seed } },
        upsert: true
      )
    rescue StandardError
      # Race — another caller seeded first; the atomic $inc below still holds.
    end
  end

  doc = sequences.find_one_and_update(
    { "_id" => seq_name },
    { "$inc" => { "current_value" => 1 } },
    return_document: :after,
    upsert: true
  )
  if doc.nil? || doc["current_value"].nil?
    raise "get_next_id: MongoDB counter '#{seq_name}' produced no value"
  end

  doc["current_value"].to_i
end

#last_insert_id ⇒ Object 



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 92

def last_insert_id
  @last_insert_id
end

#placeholder ⇒ Object 



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 139

def placeholder
  "?"
end

#placeholders(count) ⇒ Object 



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 143

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

#rollback ⇒ Object 



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 170

def rollback
  # no-op
end

#tables ⇒ Object 



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# File 'lib/tina4/drivers/mongodb_driver.rb', line 179

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