Cant see any graphs in Neo4j - neo4j

I just installed the latest version of Neo4J on ubuntu 15.04 and on my application code I have provided the path for the database as the following :
GraphDatabaseService db = dbFactory.newEmbeddedDatabase("/home/aimad/Documents/Neo4j/default.graphdb");
When I type match(n) return n; on console of http://localhost:7474 I cant see any graph.
And I notice that the location of the database is : /home/aimad/neo4j-community-2.3.0/data/graph.db on the Neo4j plateform.
I also tried to change the location of the database in conf/neo4j-server.properties but I got this error message when I want to start neo4j :
Starting Neo4j Server...WARNING: not changing user process [3151]...
waiting for server to be ready... Failed to start within 120 seconds.
Neo4j Server may have failed to start, please check the logs.
How can I solve this problem ?

As #AllessandroNegro indicated, you cannot start a neo4j server on the same DB that is already opened by an embedded app.
If you want to visualize the DB used by your embedded app, this other question might be helpful.

Related

Neo4j database will not load in my desktop application on windows

Please I am trying to access the Neo4j database via its browser. I have used both bolt//:localhost:7687 and http//:localhost:7474, and Username: "neo4j" and Password:"neo4j" but with no success. I can't even start a database instance.
I have uninstalled and reinstalled Neo4j on my computer; I have updated Powershell on my Windows 8.1 computer, yet I keep getting an error message whenever I try to run the Movie database in the desktop.
I have also looked into the log.log file, but can't seem to find anything other than that I should update Powershell, which I have done.
I have corresponded with a relations officer at Neo4j, over 30 emails, and still I can't access Neo4j database.
Could it have anything to do with my web browser? I use Mozilla Firefox.
Because I am unable to successfully connect to Neo4j database, I can't call the api in R Studio and run cypher queries.
Does Neo4j have a web version, which I could use, since the desktop version isn't working?
Please does anybody have any idea or advice on what I could do to resolve this problem? I am really exasperated right now.

Have both Gremlin-Server AND NEO4J Server running at the same time

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.

Neo4J Browser ServiceUnavailable failure after connecting with Neo4J Java driver

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

Starting Neo4j Server failed: Component was successfully initialized, but server failed to start

I was given a graph db I must open with Neo4j. Installed community version Neo4j-2.2.0-M02 on Win7 Ultimate laptop successfully. When I tried to start the server, after pointing to the graph db, I get the following error:
Starting Neo4j Server failed:
Component org.neo4j.server.database.LifecycleManagingDatabase#325ce05c was successfully initialized, but failed to start. Please see attached cause exception.
Logged in as windows local admin. Windows FWall is off. There's no antivirus SW installed on the machine. Local admin has full perms on entire root drive. When I point to the default db, Neo4j server starts normally and I can browse http://localhost:7474/ without a problem.
Any lead will be appreciated.
The aforementioned error message was the result of using a Neo4j version different to the one the graph db was originally developed. In particular, the original graph db was developed in ver 2.0.4 Community that due to my lack of knowledge I was trying to run on an installation of Neo4j ver. 2.2.0-M02 (for development only).
The code owner enlightened me to the fact and an attempt to bring up the graph db on ver. 2.0.4 Community was successful.
Thanks for your support.
Delete the folder "c:\Users\Yourname\MyDocuments\Neo4j"
I removed the plugins that were loaded from <NEO4J_HOME>/plugins as they were also loaded from under <DATABASE_HOME>/plugins

Neo4j server failed to start :( It was working fine but suddenly it throwed error while starting.

i just tried to access Neo4j through Gephi. After that when i tried to access Neo4j, it throw the following error. I'm using Neo4j 2.0.1.
Error:
Starting Neo4j Server failed: Error starting org.neo4j.kernel.EmbeddedGraphDatabase, C:\Users\Sakthi\Documents\Neo4j\default.graphdb
Make sure you don't have another Neo4j server running against the same folder
Make sure the user running gephi has read/write access to that folder
Look for the messages.log in that folder, and see if you can find any exceptions

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