README.md

In ThinkR-open/play4j: Neo4j Orchestration

Disclaimer: this package is still at an experimental level, and should only be used for testing, bug reports, and enhancement requests. As long as this package is in “Experimental” mode, some changes to the API are to be expected. Read the NEWS.md to be informed of the last changes.

This package has only been tested on these platforms for now, so it might not work on others :

• neo4j 3.3.3

  • Mac OSX

play4j

The goal of play4j is to facilitate Neo4J orchestration from R.

Installation

You can install {play4j} from GitHub with:

# install.packages("remotes")
remotes::install_github("ThinkR-open/play4j")

Example

Casual Neo4J Orchestration

• Create an instance with neo4j_shell$new and the path to your NEO4JHOME:

cypher_con <- play4j::neo4j_shell$new("/Users/colin/neo4j/")

Verify the Neo4J shell was found by running :

cypher_con$cypher_shell
#> [1] "/Users/colin/neo4j/bin/cypher-shell"

You should get a path to the cypher shell. If the returned value is character(0), please check the path you have provided.

• Start Neo4J :

# In the background
cypher_con$start()
# In the front
cypher_con$console()

• Make cypher call

You can make cypher call with the cypher method :

cypher_con$cypher(cypher = "MATCH (n) RETURN n LIMIT 5;",
          username = "neo4j", password = "pouetpouet", format = "plain")

• Restart Neo4J :

cypher_con$restart()

• See logs and certificates list :

# See the last 5 lines
cypher_con$see_logs(size = 5)
#> 2018-03-09 15:22:45.212+0000 INFO  Bolt enabled on 127.0.0.1:7687.
#> 2018-03-09 15:33:47.424+0000 INFO  ======== Neo4j 3.3.3 ========
#> 2018-03-09 15:33:47.493+0000 INFO  Starting...
#> 2018-03-09 15:33:48.229+0000 INFO  Neo4j Server shutdown initiated by request
#> 2018-03-09 15:33:49.087+0000 INFO  Bolt enabled on 127.0.0.1:7687.
cypher_con$see_certificates()
#> neo4j.cert
#> neo4j.key

You can also see plugins, imports, data and run.

• See status

cypher_con$status()

• Get Neo4J version

# Apparently not available on windows
cypher_con$version()

• Stop Neo4J

cypher_con$stop()

Neo4J API Calls

If you simply want to make API calls, start a new neo4j_api object:

api_con <- play4j::neo4j_api$new(url = "http://localhost:7474", user = "neo4j", password = "pouetpouet")

Then query (result as JSON or as an R list):

# As JSON (default)
api_con$query("MATCH (p:Person) RETURN p.name LIMIT 1")
#> [
#>   [
#>     {
#>       "row": [
#>         ["Keanu Reeves"]
#>       ],
#>       "meta": [
#>         {}
#>       ]
#>     }
#>   ]
#> ]
# As R list 
api_con$query("MATCH (p:Person) RETURN p.name LIMIT 1", format = "R")
#> [[1]]
#> [[1]][[1]]
#> [[1]][[1]]$row
#> [[1]][[1]]$row[[1]]
#> [1] "Keanu Reeves"
#> 
#> 
#> [[1]][[1]]$meta
#> [[1]][[1]]$meta[[1]]
#> NULL

Neo4J Admin Orchestration

You can call Neo4J admin commands by creating a new neo4j_admin object:

admin <- play4j::neo4j_admin$new("/Users/colin/neo4j/")

You can call admin commands with args that looks like shell commands (i.e. you should type args = "--verbose true", for example).

admin$memrec()

Every admin method comes with a help arg, that can be turned on to get the list of args to pass to the commands.

admin$check_consistency(help = TRUE)

Please note that this project is released with a Contributor Code of Conduct. By participating in this project you agree to abide by its terms.

ThinkR-open/play4j documentation built on May 25, 2019, 1:35 p.m.