Current it seems we cannot run both Neo4J Server and Gremlin Server at the same time. Is there any way to have run both?
NEO4J is running and I try to start to Gremlin Server then I get the following error
java.lang.RuntimeException: GraphFactory could not instantiate this
Graph implementation [class
org.apache.tinkerpop.gremlin.neo4j.structure.Neo4jGraph].......................(truncated)
Gremlin Server is running and I try to start NEO4J Server then I get the following error
Caused by: org.neo4j.kernel.StoreLockException: Store and its lock
file has been locked by another process:
/home/galaxia/Documents/neo4j-gremlin/data/databases/graph.db/store_lock.
Please ensure no other process is using this database, and that the
directory is writable (required even for read-only access)
Versions
Neo4J 3.3.1
Gremlin 3.3.1
I realize it has been a while, but I finally figured this out and thought others should know. As Stephen Mallette said, you can use the Bolt implementation. To configure this for Gremlin Server, use the included gremlin-server-neo4j.yaml file and make the following change:
graphs: {
graph: conf/neo4j-bolt.properties}
Then create the neo4j-bolt.properties file with this content:
gremlin.graph=com.steelbridgelabs.oss.neo4j.structure.Neo4JGraph
#neo4j.graph.name=graph.db
neo4j.identifier=dummy
neo4j.url=bolt://localhost:7687
neo4j.username=neo4j
neo4j.password=<password>
neo4j.readonly=false
neo4j.vertexIdProvider=com.steelbridgelabs.oss.neo4j.structure.providers.Neo4JNativeElementIdProvider
neo4j.edgeIdProvider=com.steelbridgelabs.oss.neo4j.structure.providers.Neo4JNativeElementIdProvider
Remember to replace the password, and any other property with the correct values.
You cannot run them together that way (i.e. embedded mode), but it should be possible to run them together, if you either:
Configure the Neo4j graph in Gremlin Server to use HA mode as described here
Configure the Neo4j graph in Gremlin Server to use the Bolt implementation found here
Enable the Bolt protocol in the Neo4j properties file provided to Gremlin Server.
As an example of the third option, given the default Gremlin Server packaged configuration files for Neo4j, you can edit conf/neo4j-empty.properties to include:
gremlin.graph=org.apache.tinkerpop.gremlin.neo4j.structure.Neo4jGraph
gremlin.neo4j.directory=/tmp/neo4j
gremlin.neo4j.conf.dbms.connector.0.type=BOLT
gremlin.neo4j.conf.dbms.connector.0.enabled=true
gremlin.neo4j.conf.dbms.connector.0.address=localhost:7687
and then start Gremlin Server with bin/gremlin-server.sh conf/gremlin-server-neo4j.yaml at which point you can use standard TinkerPop drivers as well as standard Bolt connectivity against the same graph instance.
Related
I want to create a dump of the database that JQAssistant creates with a scan. So far i have tried to do this with the integrated server and by connecting jqassistant to a running database.
The problem with the integrated database is that i can't access a shell and therefore i don't know how i could create the dump.
Connecting to the running database also didn't work. I assume the problem here is the encryption, my server is running local and trying to connect to it with
jqassistant.sh scan -f my-project.jar -storeUri bolt://localhost:7687 -storeUsername neo4j -storePassword secret
which is the example from the jqa tutorial throws the error:
javax.net.ssl.SSLHandshakeException: General SSLEngine problem
so i assume i can't connect without ssl encryption.
I am using Neo4j server 3.5.15 and JQAssistant Commandline Tool version 1.9 which uses an integrated Neo4j 3.5.14 server.
If you can give me an new idea how to create a data dump out of the scan or how to fix one of the two given problems i would appreciate that a lot!
Thanks in advance!
I couldn't figure out a way to export the database with the commandline tool, but with the maven plugin. If you setup a maven project and include jqassistant as a plugin it offers you the option "export-database" which creates a Cypher script.
I want to run gremlin-server and neo4j together.
So I make to run neo4j docker image in my machine, and try to connect it with BOLT protocol.
Could anyone help to configure .yaml/.property file in gremlin-server for this?
Used version | gremlin-server 3.4.0 & neo4j 3.2.3
The configuration options for the Graph instance property file can be found here. I'm not sure what the minimum requirements are for this provider, but from a TinkerPop perspective you need to at least specify the Graph instance with gremlin.graph and then include whatever other configurations you need to connect:
gremlin.graph=com.steelbridgelabs.oss.neo4j.structure.Neo4jGraphFactory
neo4j.hostname=...
neo4j.port=...
Then in the Gremlin Server yaml file you just reference the path to the above property file.
graphs: {
graph: conf/bolt.properties}
I am setting up window service for my neo4j database. I am able to start that from service and I can do a http post cypher query using localhost. However, I can't connect to the neo4j db remotely.
If I start the neo4j db via neo4j Desktop, I can perform http post both locally and remotely.
When I compared the neo4j logs generated using service start vs neo4j desktop start, they are quite different but no error on the service one.
Any idea?
By default, Neo4j server is not accessible remotely.
You need to change $NEO4J_HOME/conf/neo4j.conf.
Find this line:
#dbms.connector.http.address=localhost:7474
And Replace it with:
dbms.connector.http.address=0.0.0.0:7474
Setting connector address to 0.0.0.0 makes it accessible remotely.
I regularly use Neo4J Browser on http://localhost:7474/browser/. However, yesterday I used the java driver to connect to Neo4J and execute queries. Since then, I'm unable to login to Neo4J Browser.
I start Neo4J from the terminal (I'm on ubuntu) using sudo neo4j start, and this is the output -
% sudo neo4j start
Active database: graph.db
Directories in use:
home: /var/lib/neo4j
config: /etc/neo4j
logs: /var/log/neo4j
plugins: /var/lib/neo4j/plugins
import: /var/lib/neo4j/import
data: /var/lib/neo4j/data
certificates: /var/lib/neo4j/certificates
run: /var/run/neo4j
Starting Neo4j.
WARNING: Max 1024 open files allowed, minimum of 40000 recommended. See the Neo4j manual.
/usr/share/neo4j/bin/neo4j: line 411: /var/run/neo4j/neo4j.pid: No such file or directory
Then, I visit localhost:7474, which gives me the :server connect screen, but as soon as I enter the password, I get this error -
ServiceUnavailable: WebSocket connection failure. Due to security constraints in your web browser, the reason for the failure is not available to this Neo4j Driver. Please use your browsers development console to determine the root cause of the failure. Common reasons include the database being
Screenshot -
Normally, the only authentication fields are "Username" and "Password". I don't think I've seen the "Host" field in there before.
I searched for this error, and came across a question with similar error and an article on the Neo4J KB that says -
In Neo4j 3.0 and its implementation of the Bolt protocol, if a remote browser connects to Neo4j (http://:7474) and attempts to authenticate, the following error may be encountered:
But I don't think this situation applies here.
How can I fix this?
As logisima pointed out, neo4j is not compatible with Java 9. You can install multiple versions of Java and use environment variables to swap between them. For instance on MacOS you might have these two lines in your .bash_profile
export JAVA_HOME=$(/usr/libexec/java_home)
export JAVA8_HOME=/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home
The first line gets your normally installed java home and the second points to the older java8 location.
Then before starting your neo4j instance, execute for example:
export JAVA_HOME=$JAVA8_HOME
$NEO4J_HOME/bin/neo4j start
I use <neo4j:config storeDirectory="/neo4j/target/data/db"> to config my neo4j database path,
and when tomcat started, the database files are locked by tomcat, and I can't start it using Neo4j official start tool, so how can I access my database in broswer like localhost:7474, or can spring connect a lunched neo4j server like mysql? and then I can access it through broswer.
You can work with one graph instance from one place only. If you are using it via tomcat in your code you wont be able to start it from the community tool. You would need to stop your tomcat and then run the tool to view it in the browser.