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Load JSON

Procedure APOC Core

apoc.load.jsonParams('urlOrBinary',{headers}, {payload}, $config) YIELD value

It loads from JSON URL, a RestAPI endpoint URL, or from a binary source.

The headers and the payload parameters can be used to execute a RestAPI. The procedure will return multiple values if the starting JSON is a list of JSON or a single result in case it is a single JSON.

Signature

apoc.load.jsonParams(urlOrKeyOrBinary :: ANY?, headers :: MAP?, payload :: STRING?, path =  :: STRING?, config = {} :: MAP?) :: (value :: MAP?)

Input parameters

Name Type Default

urlOrKeyOrBinary

ANY?

null

headers

MAP?

null

payload

STRING?

null

path

STRING?

config

MAP?

{}

Output parameters

Name Type

value

MAP?

Reading from a file

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

apoc.conf
apoc.import.file.enabled=true

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

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

Import files are read from the import directory, which is defined by the server.directories.import property. This means that any file path that we provide is relative to this directory. If we try to read from 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.lang.RuntimeException: Can’t read url or key file:/path/to/neo4j/import/tmp/filename as json: /path/to/neo4j//import/tmp/filename (No such file or directory)

We can enable reading files from 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 read from anywhere on the file system, so be sure that this is your intention before setting this property.

Usage Examples

We can perform a POST request to a JSON endpoint by setting the config parameter method to POST. We’ll also use apoc.convert.toJson (included in APOC core) to construct a JSON payload from a Cypher map.

The following makes a POST request to Neo4j’s search API:

CALL apoc.load.jsonParams(
  "https://neo4j.com/docs/search/",
  {method: "POST"},
  apoc.convert.toJson({query: "subquery", version: "4.0"})
);
Table 1. Results
value

{description: "The CALL {} clause evaluates a subquery that returns some values.", weight: 0.6460227966308594, title: "3.16. CALL {} (subquery) - Chapter 3. Clauses", uri: "https://neo4j.com/docs/cypher-manual/4.0/clauses/call-subquery/"}

{description: "This section provides examples of queries and Cypher commands that can be used with Neo4j Fabric.", weight: 0.05099273845553398, title: "7.3. Queries - Chapter 7. Fabric", uri: "https://neo4j.com/docs/operations-manual/4.0/fabric/queries/"}

{description: "WHERE adds constraints to the patterns in a MATCH or OPTIONAL MATCH clause or filters the results of a WITH clause.", weight: 0.03291567042469978, title: "3.6. WHERE - Chapter 3. Clauses", uri: "https://neo4j.com/docs/cypher-manual/4.0/clauses/where/"}

{description: "This appendix contains the recommended style when writing Cypher queries.", weight: 0.031550146639347076, title: "Appendix A. Cypher styleguide - The Neo4j Cypher Manual v4.0", uri: "https://neo4j.com/docs/cypher-manual/4.0/styleguide/"}

{description: "This section contains information on all the clauses in the Cypher query language.", weight: 0.02944066934287548, title: "Chapter 3. Clauses - The Neo4j Cypher Manual v4.0", uri: "https://neo4j.com/docs/cypher-manual/4.0/clauses/"}

{description: "", weight: 0.01821548491716385, title: "2.3. Expressions - Chapter 2. Syntax", uri: "https://neo4j.com/docs/cypher-manual/4.0/syntax/expressions/"}