Class: Neo4jBolt::BoltSocket

Inherits:
Object
  • Object
show all
Defined in:
lib/neo4j_bolt.rb

Instance Method Summary collapse

Constructor Details

#initialize ⇒ BoltSocket

Returns a new instance of BoltSocket.



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# File 'lib/neo4j_bolt.rb', line 280

def initialize()
    reset()
end

Instance Method Details

#_append(s) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 297

def _append(s)
    @buffer += (s.is_a? String) ? s.unpack('C*') : [s]
end

#append(v) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 358

def append(v)
    if v.is_a? Array
        append_array(v)
    elsif v.is_a? Set
        append_array(v.to_a)
    elsif v.is_a? Hash
        append_dict(v)
    elsif v.is_a? String
        append_s(v)
    elsif v.is_a? Symbol
        append_s(v.to_s)
    elsif v.is_a? NilClass
        append_uint8(0xC0)
    elsif v.is_a? TrueClass
        append_uint8(0xC3)
    elsif v.is_a? FalseClass
        append_uint8(0xC2)
    elsif v.is_a? Integer
        if v >= -16 && v <= -1
            append_uint8(0x100 + v)
        elsif v >= 0 && v < 0x80
            append_uint8(v)
        elsif v >= -0x80 && v < 0x80
            append_uint8(0xC8)
            append_int8(v)
        elsif v >= -0x8000 && v < 0x8000
            append_uint8(0xC9)
            append_int16(v)
        elsif v >= -0x80000000 && v < 0x80000000
            append_uint8(0xCA)
            append_int32(v)
        elsif v >= -0x8000000000000000 && v < 0x8000000000000000
            append_uint8(0xCB)
            append_int64(v)
        else
            raise Neo4jBolt::IntegerOutOfRangeError.new()
        end
    elsif v.is_a? Float
        append_uint8(0xC1)
        _append([v].pack('G'))
    else
        raise "Type not supported: #{v.class}"
    end
end

#append_array(a) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 425

def append_array(a)
    if a.size < 16
        append_uint8(0x90 + a.size)
    elsif a.size < 0x100
        append_uint8(0xD4)
        append_uint8(a.size)
    elsif a.size < 0x10000
        append_uint8(0xD5)
        append_uint16(a.size)
    elsif a.size < 0x100000000
        append_uint8(0xD6)
        append_uint32(a.size)
    else
        raise "list cannot exceed 4G entries!"
    end
    a.each do |v|
        append(v)
    end
end

#append_dict(d) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 403

def append_dict(d)
    # STDERR.puts "Appending dict: [#{d.to_json}]"
    if d.size < 16
        append_uint8(0xA0 + d.size)
    elsif d.size < 0x100
        append_uint8(0xD8)
        append_uint8(d.size)
    elsif d.size < 0x10000
        append_uint8(0xD9)
        append_uint16(d.size)
    elsif d.size < 0x100000000
        append_uint8(0xDA)
        append_uint32(d.size)
    else
        raise "dict cannot exceed 4G entries!"
    end
    d.each_pair do |k, v|
        append_s(k)
        append(v)
    end
end

#append_int16(i) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 326

def append_int16(i)
    _append([i].pack('s>'))
end

#append_int32(i) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 330

def append_int32(i)
    _append([i].pack('l>'))
end

#append_int64(i) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 334

def append_int64(i)
    _append([i].pack('q>'))
end

#append_int8(i) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 322

def append_int8(i)
    _append([i].pack('c'))
end

#append_s(s) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 338

def append_s(s)
    s = s.to_s
    # STDERR.puts "Appending string: [#{s}]"
    if s.bytesize < 16
        append_uint8(0x80 + s.bytesize)
    elsif s.bytesize < 0x100
        append_uint8(0xD0)
        append_uint8(s.bytesize)
    elsif s.bytesize < 0x10000
        append_uint8(0xD1)
        append_uint16(s.bytesize)
    elsif s.bytesize < 0x100000000
        append_uint8(0xD2)
        append_uint32(s.bytesize)
    else
        raise "string cannot exceed 4GB!"
    end
    _append(s)
end

#append_token(i) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 305

def append_token(i)
    # STDERR.puts "Appending token: [#{BOLT_MARKER_LABELS[i]}]"
    append_uint8(i)
end

#append_uint16(i) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 310

def append_uint16(i)
    _append([i].pack('S>'))
end

#append_uint32(i) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 314

def append_uint32(i)
    _append([i].pack('L>'))
end

#append_uint64(i) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 318

def append_uint64(i)
    _append([i].pack('Q>'))
end

#append_uint8(i) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 301

def append_uint8(i)
    _append([i].pack('C'))
end

#assert(condition) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 293

def assert(condition)
    raise "Assertion failed" unless condition
end

#bolt_error(code, message) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 626

def bolt_error(code, message)
    if code == 'Neo.ClientError.Statement.SyntaxError'
        SyntaxError.new(message)
    elsif code == 'Neo.ClientError.Schema.ConstraintValidationFailed'
        ConstraintValidationFailedError.new(message)
    else
        Error.new("#{code}\n#{message}")
    end
end

#connect ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 666

def connect()
    @socket = TCPSocket.new(Neo4jBolt.bolt_host, Neo4jBolt.bolt_port)
    # The line below is important, otherwise we'll have to wait 40ms before every read
    @socket.setsockopt(Socket::IPPROTO_TCP, Socket::TCP_NODELAY, 1)
    @buffer = []
    @socket.write("\x60\x60\xB0\x17")
    @socket.write("\x00\x00\x04\x05")
    @socket.write("\x00\x00\x04\x04")
    @socket.write("\x00\x00\x00\x00")
    @socket.write("\x00\x00\x00\x00")
    @bolt_version = @socket.read(4).unpack('V').first >> 16
    # STDERR.puts "Handshake Bolt version: 0x%08x" % @bolt_version
    unless [0x0504, 0x0404].include?(@bolt_version)
        raise "Unable to establish connection to Neo4j using Bolt!"
    end
    @state.set(ServerState::CONNECTED)
    append_uint8(0xb1)
    append_token(BoltMarker::BOLT_HELLO)
    append_dict({
        :routing => nil,
        :scheme => 'none',
        :user_agent => "neo4j_bolt/#{Neo4jBolt::VERSION}",
        :bolt_agent => {
            :product => "neo4j_bolt/#{Neo4jBolt::VERSION}",
        },
    })
    flush()
    read_response() do |data|
        if data[:marker] == BoltMarker::BOLT_SUCCESS
            parts = data[:data]['server'].split('/')[1].split('.').map { |x| x.to_i}
            if @bolt_version >= 0x0501
                @state.set(ServerState::AUTHENTICATION)
                append_uint8(0xb1)
                append_token(BoltMarker::BOLT_LOGON)
                append_dict({:scheme => 'none'})
                flush()
                read_response() do |data2|
                    @state.set(ServerState::READY)
                    if data2[:marker] == BoltMarker::BOLT_SUCCESS
                        @state.set(ServerState::READY)
                    end
                end
            else
                @state.set(ServerState::READY)
            end
        elsif data[:marker] == BoltMarker::BOLT_FAILURE
            @state.set(ServerState::DEFUNCT)
        else
            raise UnexpectedServerResponse.new(data[:marker])
        end
    end

    @transaction = 0
    @transaction_failed = false
end

#disconnect ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 722

def disconnect()
    append_uint8(0xb0)
    append_token(BoltMarker::BOLT_GOODBYE)
    flush()
    @state.set(ServerState::DEFUNCT)
end

#fix_value(value) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 797

def fix_value(value)
    if value.is_a? Hash
        if value[:marker] == BoltMarker::BOLT_NODE
            Node.new(value[:id], value[:labels], fix_value(value[:properties]))
        elsif value[:marker] == BoltMarker::BOLT_RELATIONSHIP
            Relationship.new(value[:id], value[:start_node_id], value[:end_node_id], value[:type], fix_value(value[:properties]))
        else
            Hash[value.map { |k, v| [k.to_sym, fix_value(v)] }]
        end
    elsif value.is_a? Array
        value.map { |v| fix_value(v) }
    else
        value
    end
end

#flush ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 445

def flush()
    # STDERR.puts "Flushing buffer with #{@buffer.size} bytes..."

    # offset = 0
    # last_offset = 0
    # while offset < @buffer.size
    #     if offset % 16 == 0
    #         STDERR.write sprintf('%04x | ', offset)
    #     end
    #     STDERR.write sprintf("%02x ", @buffer[offset])
    #     offset += 1
    #     if offset % 16 == 0
    #         STDERR.write ' ' * 4
    #         (last_offset...offset).each do |i|
    #             b = @buffer[i]
    #             STDERR.write (b >= 32 && b < 128) ? b.chr : '.'
    #         end
    #         STDERR.puts
    #         last_offset = offset
    #     end
    # end
    # (16 - offset + last_offset).times { STDERR.write '   ' }
    # STDERR.write ' ' * 4
    # (last_offset...offset).each do |i|
    #     b = @buffer[i]
    #     STDERR.write (b >= 32 && b < 128) ? b.chr : '.'
    # end
    # STDERR.puts


    size = @buffer.size
    offset = 0
    while size > 0
        chunk_size = [size, 0xffff].min
        @socket.write([chunk_size].pack('n'))
        @socket.write(@buffer[offset, chunk_size].pack('C*'))
        offset += chunk_size
        size -= chunk_size
    end
    @socket.write([0].pack('n'))
    @buffer = []
end

#neo4j_query(query, data = {}, &block) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 873

def neo4j_query(query, data = {}, &block)
    rows = []
    run_query(query, data) do |row|
        if block_given?
            yield row
        else
            rows << row
        end
    end
    return block_given? ? nil : rows
end

#neo4j_query_expect_one(query, data = {}) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 885

def neo4j_query_expect_one(query, data = {})
    rows = neo4j_query(query, data)
    if rows.size != 1
        raise ExpectedOneResultError.new("Expected one result, but got #{rows.size}.")
    end
    rows.first
end

#parse(buf) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 548

def parse(buf)
    f = buf.peek
    if f >= 0x80 && f <= 0x8F || f == 0xD0 || f == 0xD1 || f == 0xD2
        parse_s(buf)
    elsif f >= 0x90 && f <= 0x9F || f == 0xD4 || f == 0xD5 || f == 0xD6
        parse_list(buf)
    elsif f >= 0xA0 && f <= 0xAF || f == 0xD8 || f == 0xD9 || f == 0xDA
        parse_dict(buf)
    elsif f >= 0xB0 && f <= 0xBF
        count = buf.next & 0xF
        # STDERR.puts "Parsing #{count} structures!"
        marker = buf.next

        response = {}

        if marker == BoltMarker::BOLT_SUCCESS
            response = {:marker => BoltMarker::BOLT_SUCCESS, :data => parse(buf)}
        elsif marker == BoltMarker::BOLT_FAILURE
            response = {:marker => BoltMarker::BOLT_FAILURE, :data => parse(buf)}
        elsif marker == BoltMarker::BOLT_IGNORED
            response = {:marker => BoltMarker::BOLT_IGNORED}
        elsif marker == BoltMarker::BOLT_RECORD
            response = {:marker => BoltMarker::BOLT_RECORD, :data => parse(buf)}
        elsif marker == BoltMarker::BOLT_NODE
            response = {
                :marker => BoltMarker::BOLT_NODE,
                :id => parse(buf),
                :labels => parse(buf),
                :properties => parse(buf),
            }
        elsif marker == BoltMarker::BOLT_RELATIONSHIP
            response = {
                :marker => BoltMarker::BOLT_RELATIONSHIP,
                :id => parse(buf),
                :start_node_id => parse(buf),
                :end_node_id => parse(buf),
                :type => parse(buf),
                :properties => parse(buf),
            }
        else
            raise sprintf("Unknown marker: %02x", marker)
        end
        response
    elsif f == 0xC0
        buf.next
        nil
    elsif f == 0xC1
        buf.next
        buf.next_float()
    elsif f == 0xC2
        buf.next
        false
    elsif f == 0xC3
        buf.next
        true
    elsif f == 0xC8
        buf.next
        buf.next_int8()
    elsif f == 0xC9
        buf.next
        buf.next_int16()
    elsif f == 0xCA
        buf.next
        buf.next_int32()
    elsif f == 0xCB
        buf.next
        buf.next_int64()
    elsif f >= 0xF0 && f <= 0xFF
        buf.next
        f - 0x100
    elsif f >= 0 && f <= 0x7F
        buf.next
        f
    else
        raise sprintf("Unknown marker: %02x", f)
    end
end

#parse_dict(buf) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 503

def parse_dict(buf)
    f = buf.next
    count = 0
    if f >= 0xA0 && f <= 0xAF
        count = f & 0xF
    elsif f == 0xD8
        count = buf.next_uint8()
    elsif f == 0xD9
        count = buf.next_uint16()
    elsif f == 0xDA
        count = buf.next_uint32()
    else
        raise sprintf("unknown string dict %02x", f)
    end
    # STDERR.puts "Parsing dict with #{count} entries"
    v = {}
    (0...count).map do
        key = parse_s(buf)
        value = parse(buf)
        # STDERR.puts "#{key.to_s}: #{value.to_s}"
        v[key] = value
    end
    v
end

#parse_list(buf) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 528

def parse_list(buf)
    f = buf.next
    count = 0
    if f >= 0x90 && f <= 0x9F
        count = f & 0x0F
    elsif f == 0xD4
        count = buf.next_uint8()
    elsif f == 0xD5
        count = buf.next_uint16()
    elsif f == 0xD6
        count = buf.next_uint32()
    else
        raise sprintf("unknown list format %02x", f)
    end
    v = {}
    (0...count).map do
        parse(buf)
    end
end

#parse_s(buf) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 488

def parse_s(buf)
    f = buf.next
    if f >= 0x80 && f <= 0x8F
        buf.next_s(f & 0xF)
    elsif f == 0xD0
        buf.next_s(buf.next_uint8())
    elsif f == 0xD1
        buf.next_s(buf.next_uint16())
    elsif f == 0xD2
        buf.next_s(buf.next_uint32())
    else
        raise CypherError.new(sprintf("unknown string format %02x", f), buf)
    end
end

#read_response(&block) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 636

def read_response(&block)
    loop do
        # STDERR.puts "Reading response:"
        buffer = BoltBuffer.new(@socket)
        # buffer.dump
        response_dict = parse(buffer)
        buffer.flush()
        # STDERR.puts "Response marker: #{BOLT_MARKER_LABELS[response_dict[:marker]]}"
        # STDERR.puts response_dict.to_yaml
        if response_dict[:marker] == BoltMarker::BOLT_FAILURE
            # STDERR.puts "RESETTING CONNECTION"
            append_uint8(0xb0)
            append_token(BoltMarker::BOLT_RESET)
            flush()
            read_response() do |data|
                if data[:marker] == BoltMarker::BOLT_SUCCESS
                    @state.set(ServerState::READY)
                else
                    raise UnexpectedServerResponse.new(data[:marker])
                end
            end
            # BoltBuffer.new(@socket).flush()
            raise bolt_error(response_dict[:data]['code'], response_dict[:data]['message'])
        end
        # STDERR.puts response_dict.to_json
        yield response_dict if block_given?
        break if [BoltMarker::BOLT_SUCCESS, BoltMarker::BOLT_FAILURE, BoltMarker::BOLT_IGNORED].include?(response_dict[:marker])
    end
end

#reset ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 284

def reset()
    @socket = nil
    @transaction = 0
    @transaction_failed = false
    @state = State.new()
    @neo4j_version = nil
    @pidtid = "#{Process.pid}/#{Thread.current.object_id}"
end

#run_query(query, data = {}, &block) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 813

def run_query(query, data = {}, &block)
    if Neo4jBolt.bolt_verbosity >= 1
        STDERR.puts query
        STDERR.puts data.to_json
        STDERR.puts '-' * 40
    end
    transaction do
        assert(@state == ServerState::TX_READY || @state == ServerState::TX_STREAMING || @state == ServerState::FAILED)
        append_uint8(0xb3)
        append_token(BoltMarker::BOLT_RUN)
        append_s(query)
        # Because something might go wrong while filling the buffer with
        # the request data (for example if the data contains 2^100 anywhere)
        # we catch any errors that happen here and if things go wrong, we
        # clear the buffer so that the BOLT_RUN stanza never gets sent
        # to Neo4j - instead, the transaction gets rolled back
        begin
            append_dict(data)
        rescue
            @buffer = []
            raise
        end
        append_dict({}) # options
        flush()
        read_response do |data|
            if data[:marker] == BoltMarker::BOLT_SUCCESS
                @state.set(ServerState::TX_STREAMING)
                keys = data[:data]['fields']
                assert(@state == ServerState::TX_STREAMING)
                append_uint8(0xb1)
                append_token(BoltMarker::BOLT_PULL)
                append_dict({:n => -1})
                flush()
                read_response do |data|
                    if data[:marker] == BoltMarker::BOLT_RECORD
                        entry = {}
                        keys.each.with_index do |key, i|
                            entry[key] = fix_value(data[:data][i])
                        end
                        if Neo4jBolt.bolt_verbosity >= 1
                            STDERR.puts ">>> #{entry.to_json}"
                            STDERR.puts '-' * 40
                        end
                        yield entry
                    elsif data[:marker] == BoltMarker::BOLT_SUCCESS
                        # STDERR.puts data.to_yaml
                        @state.set(ServerState::TX_READY)
                    else
                        raise UnexpectedServerResponse.new(data[:marker])
                    end
                end
            elsif data[:marker] == BoltMarker::BOLT_FAILURE
                @state.set(ServerState::FAILED)
            else
                raise UnexpectedServerResponse.new(data[:marker])
            end
        end
    end
end

#setup_constraints_and_indexes(constraints, indexes) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 893

def setup_constraints_and_indexes(constraints, indexes)
    wanted_constraints = Set.new()
    wanted_indexes = Set.new()
    # STDERR.puts "Setting up constraints and indexes..."
    constraints.each do |constraint|
        unless constraint =~ /\w+\/\w+/
            raise "Unexpected constraint format: #{constraint}"
        end
        constraint_name = "#{CONSTRAINT_INDEX_PREFIX}#{constraint.gsub('/', '_')}"
        wanted_constraints << constraint_name
        label = constraint.split('/').first
        property = constraint.split('/').last
        query = "CREATE CONSTRAINT #{constraint_name} IF NOT EXISTS FOR (n:#{label}) REQUIRE n.#{property} IS UNIQUE"
        # STDERR.puts query
        neo4j_query(query)
    end
    indexes.each do |index|
        unless index =~ /\w+\/\w+/
            raise "Unexpected index format: #{index}"
        end
        index_name = "#{CONSTRAINT_INDEX_PREFIX}#{index.gsub('/', '_')}"
        wanted_indexes << index_name
        label = index.split('/').first
        property = index.split('/').last
        query = "CREATE INDEX #{index_name} IF NOT EXISTS FOR (n:#{label}) ON (n.#{property})"
        # STDERR.puts query
        neo4j_query(query)
    end
    neo4j_query("SHOW ALL CONSTRAINTS").each do |row|
        next unless row['name'].index(CONSTRAINT_INDEX_PREFIX) == 0
        next if wanted_constraints.include?(row['name'])
        query = "DROP CONSTRAINT #{row['name']}"
        # STDERR.puts query
        neo4j_query(query)
    end
    neo4j_query("SHOW ALL INDEXES").each do |row|
        next unless row['name'].index(CONSTRAINT_INDEX_PREFIX) == 0
        next if wanted_indexes.include?(row['name']) || wanted_constraints.include?(row['name'])
        query = "DROP INDEX #{row['name']}"
        # STDERR.puts query
        neo4j_query(query)
    end
end

#transaction(&block) ⇒ Object 



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# File 'lib/neo4j_bolt.rb', line 729

def transaction(&block)
    reset() if @pidtid != "#{Process.pid}/#{Thread.current.object_id}"
    connect() if @socket.nil?
    if @transaction == 0
        # STDERR.puts '*' * 40
        # STDERR.puts "#{SERVER_STATE_LABELS[@state.to_i]} (#{@state.to_i})"
        # STDERR.puts '*' * 40
        assert(@state == ServerState::READY)
        append_uint8(0xb1)
        append_token(BoltMarker::BOLT_BEGIN)
        append_dict({})
        flush()
        read_response() do |data|
            if data[:marker] == BoltMarker::BOLT_SUCCESS
                @state.set(ServerState::TX_READY)
                @transaction_failed = false
            elsif data[:marker] == BoltMarker::BOLT_FAILURE
                @state.set(ServerState::FAILED)
            else
                raise UnexpectedServerResponse.new(data[:marker])
            end
        end
    end
    @transaction += 1
    begin
        yield
    rescue
        @transaction_failed = true
        raise
    ensure
        @transaction -= 1
        if @transaction == 0 && @transaction_failed
            # TODO: Not sure about this, read remaining response but don't block
            # read_response()
            # STDERR.puts "!!! Rolling back transaction !!! --- state is #{@state}"
            if @state == ServerState::TX_READY
                assert(@state == ServerState::TX_READY)
                append_uint8(0xb0)
                append_token(BoltMarker::BOLT_ROLLBACK)
                flush()
                read_response do |data|
                    if data[:marker] == BoltMarker::BOLT_SUCCESS
                        @state.set(ServerState::READY)
                    elsif data[:marker] == BoltMarker::BOLT_FAILURE
                        @state.set(ServerState::FAILED)
                    else
                        raise UnexpectedServerResponse.new(data[:marker])
                    end
                end
            end
        end
    end
    if (@transaction == 0) && (!@transaction_failed)
        append_uint8(0xb0)
        append_token(BoltMarker::BOLT_COMMIT)
        flush()
        read_response() do |data|
            if data[:marker] == BoltMarker::BOLT_SUCCESS
                @transaction = 0
                @transaction_failed = false
                @state.set(ServerState::READY)
            else
                raise UnexpectedServerResponse.new(data[:marker])
            end
        end
    end
end