我的环境是:
java -version
java version "1.8.0_172"
Java(TM) SE Runtime Environment (build 1.8.0_172-b11)
Java HotSpot(TM) 64-Bit Server VM (build 25.172-b11, mixed mode)
python3 --version
Python 3.7.4
这应该是唯一相关的环境部分。不幸的是,我在 MacOS 上使用 macports 可能会有所不同,这应该不是问题。
我刚刚在 Ubuntu 18.04 LTS 上测试了东西,请参阅http://wiki.bitplan.com/index.php/Gremlin_python#Installlation_automation并且行为是相同的。
所以我想试用 gremlin-python。我找到了https://pypi.org/project/gremlinpython/ 并愉快地添加了
gremlinpython
到我的requirements.txt
sudo -H pip install -r requirements.txt
成功运行——太好了。让我们找一些 python 代码来玩。
有它。
哦-我需要一个服务器...
让我们下载它
解压缩并为其创建一个启动文件,如上例所述:
gspath=$HOME/Downloads/apache-tinkerpop-gremlin-server-3.4.3
#$gspath/bin/gremlin-server.sh install org.apache.tinkerpop gremlin-python 3.4.3
$gspath/bin/gremlin-server.sh $gspath/conf/gremlin-server-modern-py.yaml
它不起作用 - 从龙卷风中获得 599 超时。
看着:
尝试提示,例如使用 0.0.0.0 作为主机
检查启动。
糟糕 - 出现错误:
Could not initialize gremlin-jython GremlinScriptEngine as init script could not be evaluated
java.util.concurrent.CompletionException: java.lang.IllegalArgumentException: gremlin-jython is not an available GremlinScriptEngine
at java.util.concurrent.CompletableFuture.reportJoin(CompletableFuture.java:375)
at java.util.concurrent.CompletableFuture.join(CompletableFuture.java:1934)
at org.apache.tinkerpop.gremlin.server.util.ServerGremlinExecutor.lambda$new$4(ServerGremlinExecutor.java:141)
at java.util.LinkedHashMap$LinkedKeySet.forEach(LinkedHashMap.java:559)
at org.apache.tinkerpop.gremlin.server.util.ServerGremlinExecutor.<init>(ServerGremlinExecutor.java:136)
at org.apache.tinkerpop.gremlin.server.GremlinServer.<init>(GremlinServer.java:122)
at org.apache.tinkerpop.gremlin.server.GremlinServer.<init>(GremlinServer.java:86)
at org.apache.tinkerpop.gremlin.server.GremlinServer.main(GremlinServer.java:345)
Caused by: java.lang.IllegalArgumentException: gremlin-jython is not an available GremlinScriptEngine
at org.apache.tinkerpop.gremlin.jsr223.CachedGremlinScriptEngineManager.registerLookUpInfo(CachedGremlinScriptEngineManager.java:95)
at org.apache.tinkerpop.gremlin.jsr223.CachedGremlinScriptEngineManager.getEngineByName(CachedGremlinScriptEngineManager.java:58)
at org.apache.tinkerpop.gremlin.groovy.engine.GremlinExecutor.lambda$eval$0(GremlinExecutor.java:266)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
[WARN] ServerGremlinExecutor - Could not initialize gremlin-python GremlinScriptEngine as init script could not be evaluated
java.util.concurrent.CompletionException: java.lang.IllegalArgumentException: gremlin-python is not an available GremlinScriptEngine
at java.util.concurrent.CompletableFuture.reportJoin(CompletableFuture.java:375)
at java.util.concurrent.CompletableFuture.join(CompletableFuture.java:1934)
at org.apache.tinkerpop.gremlin.server.util.ServerGremlinExecutor.lambda$new$4(ServerGremlinExecutor.java:141)
at java.util.LinkedHashMap$LinkedKeySet.forEach(LinkedHashMap.java:559)
at org.apache.tinkerpop.gremlin.server.util.ServerGremlinExecutor.<init>(ServerGremlinExecutor.java:136)
at org.apache.tinkerpop.gremlin.server.GremlinServer.<init>(GremlinServer.java:122)
at org.apache.tinkerpop.gremlin.server.GremlinServer.<init>(GremlinServer.java:86)
at org.apache.tinkerpop.gremlin.server.GremlinServer.main(GremlinServer.java:345)
Caused by: java.lang.IllegalArgumentException: gremlin-python is not an available GremlinScriptEngine
at org.apache.tinkerpop.gremlin.jsr223.CachedGremlinScriptEngineManager.registerLookUpInfo(CachedGremlinScriptEngineManager.java:95)
at org.apache.tinkerpop.gremlin.jsr223.CachedGremlinScriptEngineManager.getEngineByName(CachedGremlinScriptEngineManager.java:58)
at org.apache.tinkerpop.gremlin.groovy.engine.GremlinExecutor.lambda$eval$0(GremlinExecutor.java:266)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
gremlin-python 不是可用的 GremlinScriptEngine
提到应该安装服务器的插件。我以为
$gspath/bin/gremlin-server.sh install org.apache.tinkerpop gremlin-python 3.4.3
会这样做,当我再次运行它时,我得到:
Installing dependency org.apache.tinkerpop gremlin-python 3.4.3
Could not install the dependency: a module with the name gremlin-python is already installed
如何从这里开始工作?
我将python测试代码缩减为:
# https://pypi.org/project/gremlinpython/
# start GremlinServer
# bin/gremlin-server.sh -i org.apache.tinkerpop gremlin-python 3.2.2-SNAPSHOT
# bin/gremlin-server.sh conf/gremlin-server-modern-py.yaml
# in practice, you really only need the 3 imports below
from gremlin_python import statics
from gremlin_python.structure.graph import Graph
from gremlin_python.driver.driver_remote_connection import DriverRemoteConnection
# this allows us to do g.V().repeat(out()) instead of g.V().repeat(__.out())-type traversals
#statics.load_statics(globals())
# create a remote connection using RemoteStrategy
graph = Graph()
g = graph.traversal().withRemote(DriverRemoteConnection('ws://localhost:8182','g'))
print (g.V().count().value())