apoc.export.json.data

Procedure APOC Core

apoc.export.json.data(nodes,rels,file,config) - exports given nodes and relationships as json to the provided file

Signature

apoc.export.json.data(nodes :: LIST? OF NODE?, rels :: LIST? OF RELATIONSHIP?, file :: STRING?, config = {} :: MAP?) :: (file :: STRING?, source :: STRING?, format :: STRING?, nodes :: INTEGER?, relationships :: INTEGER?, properties :: INTEGER?, time :: INTEGER?, rows :: INTEGER?, batchSize :: INTEGER?, batches :: INTEGER?, done :: BOOLEAN?, data :: STRING?)

Input parameters

Name	Type	Default
nodes	LIST? OF NODE?	null
rels	LIST? OF RELATIONSHIP?	null
file	STRING?	null
config	MAP?	{}

Name

Type

Default

nodes

LIST? OF NODE?

null

rels

LIST? OF RELATIONSHIP?

null

file

STRING?

null

config

MAP?

{}

Config parameters

The procedure support the following config parameters:

Table 1. Config parameters
name	type	default	description
writeNodeProperties	boolean	false	if true export properties too.
stream	boolean	false	stream the json directly to the client into the `data` field

Output parameters

Name	Type
file	STRING?
source	STRING?
format	STRING?
nodes	INTEGER?
relationships	INTEGER?
properties	INTEGER?
time	INTEGER?
rows	INTEGER?
batchSize	INTEGER?
batches	INTEGER?
done	BOOLEAN?
data	STRING?

Name

Type

file

STRING?

source

STRING?

format

STRING?

nodes

INTEGER?

relationships

INTEGER?

properties

INTEGER?

time

INTEGER?

rows

INTEGER?

batchSize

INTEGER?

batches

INTEGER?

done

BOOLEAN?

data

STRING?

Exporting to a file

By default exporting to the file system is disabled. We can enable it by setting the following property in apoc.conf:

apoc.conf

apoc.export.file.enabled=true

If we try to use any of the export procedures without having first set this property, we’ll get the following error message:

Failed to invoke procedure: Caused by: java.lang.RuntimeException: Export to files not enabled, please set apoc.export.file.enabled=true in your neo4j.conf

Export files are written to the import directory, which is defined by the dbms.directories.import property. This means that any file path that we provide is relative to this directory. If we try to write to an absolute path, such as /tmp/filename, we’ll get an error message similar to the following one:

Failed to invoke procedure: Caused by: java.io.FileNotFoundException: /path/to/neo4j/import/tmp/fileName (No such file or directory)

We can enable writing to anywhere on the file system by setting the following property in apoc.conf:

apoc.conf

apoc.import.file.use_neo4j_config=false

Neo4j will now be able to write anywhere on the file system, so be sure that this is your intention before setting this property.

Exporting a stream

If we don’t want to export to a file, we can stream results back in the data column instead by passing a file name of null and providing the stream:true config.

Usage Examples

The examples in this section are based on the following sample graph:

CREATE (a:User {
    name:'Adam', age:42, male:true, kids:['Sam','Anna','Grace'],
    born:localdatetime('2015185T19:32:24'),
    place:point({latitude: 13.1, longitude: 33.46789})
})
CREATE (b:User {name:'Jim', age:42})
CREATE (c:User {age:12})

CREATE (a)-[:KNOWS {since: 1993}]->(b);

The following query exports all KNOWS relationships and User nodes to the file knows.json

MATCH (nod:User)
MATCH ()-[rels:KNOWS]->()
WITH collect(nod) as a, collect(rels) as b
CALL apoc.export.json.data(a, b, "knows.json", null)
YIELD file, source, format, nodes, relationships, properties, time, rows, batchSize, batches, done, data
RETURN file, source, format, nodes, relationships, properties, time, rows, batchSize, batches, done, data

Table 2. Results
file	source	format	nodes	relationships	properties	time	rows	batchSize	batches	done	data
"knows.json"	"data: nodes(3), rels(3)"	"json"	3	1	10	1	0	-1	0	TRUE	NULL

The contents of knows.json are shown below:

knows.json

{"type":"node","id":"0","labels":["User"],"properties":{"born":"2015-07-04T19:32:24","name":"Adam","place":{"crs":"wgs-84","latitude":13.1,"longitude":33.46789,"height":null},"age":42,"male":true,"kids":["Sam","Anna","Grace"]}}
{"type":"node","id":"1","labels":["User"],"properties":{"name":"Jim","age":42}}
{"type":"node","id":"2","labels":["User"],"properties":{"age":12}}
{"id":"0","type":"relationship","label":"KNOWS","properties":{"bffSince":"P5M1DT12H","since":1993},"start":{"id":"0","labels":["User"]},"end":{"id":"1","labels":["User"]}}

The following query return a stream of all KNOWS relationships and User nodes in the data column

MATCH (nod:User)
MATCH ()-[rels:KNOWS]->()
WITH collect(nod) as a, collect(rels) as b
CALL apoc.export.json.data(a, b, null, {stream: true})
YIELD file, nodes, relationships, properties, data
RETURN file, nodes, relationships, properties, data

Table 3. Results
file	nodes	relationships	properties	data
NULL	3	1	10	"{\"type\":\"node\",\"id\":\"0\",\"labels\":[\"User\"],\"properties\":{\"born\":\"2015-07-04T19:32:24\",\"name\":\"Adam\",\"place\":{\"crs\":\"wgs-84\",\"latitude\":33.46789,\"longitude\":13.1,\"height\":null},\"age\":42,\"male\":true,\"kids\":[\"Sam\",\"Anna\",\"Grace\"]}} {\"type\":\"node\",\"id\":\"1\",\"labels\":[\"User\"],\"properties\":{\"name\":\"Jim\",\"age\":42}} {\"type\":\"node\",\"id\":\"2\",\"labels\":[\"User\"],\"properties\":{\"age\":12}} {\"id\":\"50000\",\"type\":\"rel

More documentation of apoc.export.json.data