Module: Neo4jBolt

Defined in:

lib/neo4j_bolt.rb,
lib/neo4j_bolt/version.rb

Defined Under Namespace

Modules: BoltMarker, ServerState Classes: BoltBuffer, BoltSocket, ConstraintValidationFailedError, CypherError, Error, ExpectedOneResultError, IntegerOutOfRangeError, Node, Relationship, State, SyntaxError, UnexpectedServerResponse

Constant Summary

CONSTRAINT_INDEX_PREFIX =

'neo4j_bolt_'

SERVER_STATE_LABELS =

Hash[ServerState::constants.map { |value| [ServerState::const_get(value), value]

BOLT_MARKER_LABELS =

VERSION =

"0.3.0"

Class Attribute Summary

• .bolt_host ⇒ Object

  Returns the value of attribute bolt_host.

• .bolt_port ⇒ Object

  Returns the value of attribute bolt_port.

• .bolt_verbosity ⇒ Object

  Returns the value of attribute bolt_verbosity.

Instance Method Summary

• #cleanup_neo4j ⇒ Object
• #dump_database(io) ⇒ Object
• #load_database_dump(io, force_append: false) ⇒ Object
• #neo4j_query(query, data = {}, &block) ⇒ Object
• #neo4j_query_expect_one(query, data = {}) ⇒ Object
• #rollback ⇒ Object
• #setup_constraints_and_indexes(constraints, indexes) ⇒ Object
• #transaction(&block) ⇒ Object
• #wait_for_neo4j ⇒ Object

Class Attribute Details

.bolt_host ⇒ Object

Returns the value of attribute bolt_host.

# File 'lib/neo4j_bolt.rb', line 9

def bolt_host
  @bolt_host
end

.bolt_port ⇒ Object

Returns the value of attribute bolt_port.

# File 'lib/neo4j_bolt.rb', line 9

def bolt_port
  @bolt_port
end

.bolt_verbosity ⇒ Object

Returns the value of attribute bolt_verbosity.

# File 'lib/neo4j_bolt.rb', line 9

def bolt_verbosity
  @bolt_verbosity
end

Instance Method Details

#cleanup_neo4j ⇒ Object

# File 'lib/neo4j_bolt.rb', line 1074

def cleanup_neo4j
    if @bolt_socket
        @bolt_socket.disconnect()
        @bolt_socket = nil
    end
end

#dump_database(io) ⇒ Object

# File 'lib/neo4j_bolt.rb', line 970

def dump_database(io)
    tr_id = {}
    id = 0
    neo4j_query("MATCH (n) RETURN n ORDER BY ID(n);") do |row|
        tr_id[row['n'].id] = id
        node = {
            :id => id,
            :labels => row['n'].labels,
            :properties => row['n']
        }
        io.puts "n #{node.to_json}"
        id += 1
    end
    neo4j_query("MATCH ()-[r]->() RETURN r;") do |row|
        rel = {
            :from => tr_id[row['r'].start_node_id],
            :to => tr_id[row['r'].end_node_id],
            :type => row['r'].type,
            :properties => row['r']
        }
        io.puts "r #{rel.to_json}"
    end
end

#load_database_dump(io, force_append: false) ⇒ Object

# File 'lib/neo4j_bolt.rb', line 994

def load_database_dump(io, force_append: false)
    unless force_append
        transaction do
            node_count = neo4j_query_expect_one('MATCH (n) RETURN COUNT(n) as count;')['count']
            unless node_count == 0
                raise "There are nodes in this database, exiting now."
            end
        end
    end
    n_count = 0
    r_count = 0
    node_tr = {}
    node_batch_by_label = {}
    relationship_batch_by_type = {}
    io.each_line do |line|
        line.strip!
        next if line.empty?
        if line[0] == 'n'
            line = line[2, line.size - 2]
            node = JSON.parse(line)
            label_key = node['labels'].sort.join('/')
            node_batch_by_label[label_key] ||= []
            node_batch_by_label[label_key] << node
        elsif line[0] == 'r'
            line = line[2, line.size - 2]
            relationship = JSON.parse(line)
            relationship_batch_by_type[relationship['type']] ||= []
            relationship_batch_by_type[relationship['type']] << relationship
        else
            STDERR.puts "Invalid entry: #{line}"
            exit(1)
        end
    end
    node_batch_by_label.each_pair do |label_key, batch|
        while !batch.empty? do
            slice = []
            json_size = 0
            while (!batch.empty?) && json_size < 0x20000 && slice.size < 256
                x = batch.shift
                slice << x
                json_size += x.to_json.size
            end
            ids = neo4j_query(<<~END_OF_QUERY, {:properties => slice.map { |x| x['properties']}})
                UNWIND $properties AS props
                CREATE (n:#{slice.first['labels'].join(':')})
                SET n = props
                RETURN ID(n) AS id;
            END_OF_QUERY
            slice.each.with_index do |node, i|
                node_tr[node['id']] = ids[i]['id']
            end
            n_count += slice.size
            STDERR.print "\rLoaded #{n_count} nodes, #{r_count} relationships..."
        end
    end
    relationship_batch_by_type.each_pair do |rel_type, batch|
        batch.each_slice(256) do |slice|
            slice.map! do |rel|
                rel['from'] = node_tr[rel['from']]
                rel['to'] = node_tr[rel['to']]
                rel
            end
            count = neo4j_query_expect_one(<<~END_OF_QUERY, {:slice => slice})['count_r']
                UNWIND $slice AS props
                MATCH (from), (to) WHERE ID(from) = props.from AND ID(to) = props.to
                CREATE (from)-[r:#{rel_type}]->(to)
                SET r = props.properties
                RETURN COUNT(r) AS count_r, COUNT(from) AS count_from, COUNT(to) AS count_to;
            END_OF_QUERY
            if count != slice.size
                raise "Ooops... expected #{slice.size} relationships, got #{count}."
            end
            r_count += slice.size
            STDERR.print "\rLoaded #{n_count} nodes, #{r_count} relationships..."
        end
    end

    STDERR.puts
end

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

# File 'lib/neo4j_bolt.rb', line 947

def neo4j_query(query, data = {}, &block)
    @bolt_socket ||= BoltSocket.new()
    @bolt_socket.neo4j_query(query, data, &block)
end

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

# File 'lib/neo4j_bolt.rb', line 952

def neo4j_query_expect_one(query, data = {})
    @bolt_socket ||= BoltSocket.new()
    @bolt_socket.neo4j_query_expect_one(query, data)
end

#rollback ⇒ Object

# File 'lib/neo4j_bolt.rb', line 943

def rollback()
    @bolt_socket.rollback
end

#setup_constraints_and_indexes(constraints, indexes) ⇒ Object

# File 'lib/neo4j_bolt.rb', line 1081

def setup_constraints_and_indexes(constraints, indexes)
    @bolt_socket ||= BoltSocket.new()
    @bolt_socket.setup_constraints_and_indexes(constraints, indexes)
end

#transaction(&block) ⇒ Object

# File 'lib/neo4j_bolt.rb', line 938

def transaction(&block)
    @bolt_socket ||= BoltSocket.new()
    @bolt_socket.transaction { yield }
end

#wait_for_neo4j ⇒ Object

# File 'lib/neo4j_bolt.rb', line 957

def wait_for_neo4j
    delay = 1
    10.times do
        begin
            neo4j_query("MATCH (n) RETURN n LIMIT 1;")
        rescue
            debug "Waiting #{delay} seconds for Neo4j to come up..."
            sleep delay
            delay += 1
        end
    end
end