使用nifi executescript在python中没有可行的替代错误

Question

我正在使用python脚本抓取页面（例如facebook页面），并希望传递要写入文件的每个帖子（类似于gettwitter进程）。 我正在使用Apache Nifi ExecuteScript处理器来调用python脚本。

但是，我得到了SyntaxError: no viable alternative at input

我可以成功地在处理器之间传输数据，但是当我尝试添加剪贴代码时，我总是出错。 我正在使用python 2.7.8版本。 据我了解，executeScript在内部使用jython，而jython可以翻译python代码。

如果删除与nifi相关的代码（内部类和流文件），则以下代码可在nifi外与python正常工作。

import urllib2
import json
import datetime
import csv
import time
import sys
import traceback
from org.apache.nifi.processor.io import OutputStreamCallback
from org.python.core.util import StringUtil

class WriteContentCallback(OutputStreamCallback):
    def __init__(self, content):
        self.content_text = content

    def process(self, outputStream):
        try:
            outputStream.write(StringUtil.toBytes(self.content_text))
        except:
            traceback.print_exc(file=sys.stdout)
            raise

#app_id = "<FILL IN>"
#app_secret = "<FILL IN>" # DO NOT SHARE WITH ANYONE!
page_id = "dsssssss"
#page_id = raw_input("Please Paste Public Page Name:")

#access_token = app_id + "|" + app_secret

access_token = "sdfsdfsf%sdfsdf"

#access_token = raw_input("Please Paste Your Access Token:")


def scrapeFacebookPageFeedStatus(page_id, access_token):
    flowFile = session.create()
    flowFile = session.write(flowFile, WriteContentCallback("Hello there this is my data")
    #flowFile = session.write()
    #session.transfer(flowFile, REL_SUCCESS)


        has_next_page = False
        num_processed = 0   # keep a count on how many we've processed
        scrape_starttime = datetime.datetime.now()


        while has_next_page:
            print "Scraping %s Facebook Page: %s\n" % (page_id, scrape_starttime)
            has_next_page = False

        print "\nDone!\n%s Statuses Processed in %s" % \
                (num_processed, datetime.datetime.now() - scrape_starttime)


if __name__ == '__main__':
    #scrapeFacebookPageFeedStatus(page_id, access_token)
    flowFile = session.create()
    flowFile = session.write(flowFile, WriteContentCallback("Hello there this is my data")
    session.transfer(flowFile, REL_SUCCESS)

以下是错误的完整信息

> 2017-04-02 16:19:22,817 ERROR [Timer-Driven Process Thread-10]
> o.a.nifi.processors.script.ExecuteScript
> ExecuteScript[id=a62f4b97-8fd7-15cd-95b9-505e1b960805]
> ExecuteScript[id=a62f4b97-8fd7-15cd-95b9-505e1b960805] failed to
> process due to org.apache.nifi.processor.exception.ProcessException:
> javax.script.ScriptException: SyntaxError: no viable alternative at
> input 'has_next_page' in <script> at line number 178 at column number
> 8; rolling back session:
> org.apache.nifi.processor.exception.ProcessException:
> javax.script.ScriptException: SyntaxError: no viable alternative at
> input 'has_next_page' in <script> at line number 178 at column number
> 8 2017-04-02 16:19:22,819 ERROR [Timer-Driven Process Thread-10]
> o.a.nifi.processors.script.ExecuteScript
> org.apache.nifi.processor.exception.ProcessException:
> javax.script.ScriptException: SyntaxError: no viable alternative at
> input 'has_next_page' in <script> at line number 178 at column number
> 8
>         at org.apache.nifi.processors.script.ExecuteScript.onTrigger(ExecuteScript.java:214)
> ~[nifi-scripting-processors-1.1.0.2.1.1.0-2.jar:1.1.0.2.1.1.0-2]
>         at org.apache.nifi.controller.StandardProcessorNode.onTrigger(StandardProcessorNode.java:1099)
> [nifi-framework-core-1.1.0.2.1.1.0-2.jar:1.1.0.2.1.1.0-2]
>         at org.apache.nifi.controller.tasks.ContinuallyRunProcessorTask.call(ContinuallyRunProcessorTask.java:136)
> [nifi-framework-core-1.1.0.2.1.1.0-2.jar:1.1.0.2.1.1.0-2]
>         at org.apache.nifi.controller.tasks.ContinuallyRunProcessorTask.call(ContinuallyRunProcessorTask.java:47)
> [nifi-framework-core-1.1.0.2.1.1.0-2.jar:1.1.0.2.1.1.0-2]
>         at org.apache.nifi.controller.scheduling.TimerDrivenSchedulingAgent$1.run(TimerDrivenSchedulingAgent.java:132)
> [nifi-framework-core-1.1.0.2.1.1.0-2.jar:1.1.0.2.1.1.0-2]
>         at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
> [na:1.8.0_77]
>         at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308)
> [na:1.8.0_77]
>         at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:180)
> [na:1.8.0_77]
>         at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:294)
> [na:1.8.0_77]
>         at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
> [na:1.8.0_77]
>         at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
> [na:1.8.0_77]
>         at java.lang.Thread.run(Thread.java:745) [na:1.8.0_77] Caused by: javax.script.ScriptException: SyntaxError: no viable alternative
> at input 'has_next_page' in <script> at line number 178 at column
> number 8
>         at org.python.jsr223.PyScriptEngine.scriptException(PyScriptEngine.java:190)
> ~[jython-standalone-2.7.0.jar:na]
>         at org.python.jsr223.PyScriptEngine.compileScript(PyScriptEngine.java:75)
> ~[jython-standalone-2.7.0.jar:na]
>         at org.python.jsr223.PyScriptEngine.eval(PyScriptEngine.java:31)
> ~[jython-standalone-2.7.0.jar:na]
>         at javax.script.AbstractScriptEngine.eval(AbstractScriptEngine.java:264)
> ~[na:1.8.0_77]
>         at org.apache.nifi.processors.script.impl.JythonScriptEngineConfigurator.eval(JythonScriptEngineConfigurator.java:59)
> ~[nifi-scripting-processors-1.1.0.2.1.1.0-2.jar:1.1.0.2.1.1.0-2]
>         at org.apache.nifi.processors.script.ExecuteScript.onTrigger(ExecuteScript.java:204)
> ~[nifi-scripting-processors-1.1.0.2.1.1.0-2.jar:1.1.0.2.1.1.0-2]
>         ... 11 common frames omitted Caused by: org.python.core.PySyntaxError: null
>         at org.python.core.ParserFacade.fixParseError(ParserFacade.java:95)
> ~[jython-standalone-2.7.0.jar:na]
>         at org.python.core.ParserFacade.parseExpressionOrModule(ParserFacade.java:136)
> ~[jython-standalone-2.7.0.jar:na]
>         at org.python.util.PythonInterpreter.compile(PythonInterpreter.java:320)
> ~[jython-standalone-2.7.0.jar:na]
>         at org.python.util.PythonInterpreter.compile(PythonInterpreter.java:316)
> ~[jython-standalone-2.7.0.jar:na]
>         at org.python.util.PythonInterpreter.compile(PythonInterpreter.java:308)
> ~[jython-standalone-2.7.0.jar:na]
>         at org.python.jsr223.PyScriptEngine.compileScript(PyScriptEngine.java:70)
> ~[jython-standalone-2.7.0.jar:na]
>         ... 15 common frames omitted

感谢您的指导。 谢谢。

Answer 1

从源代码看来，您在以下行上缺少右括号：

flowFile = session.write(flowFile, WriteContentCallback("Hello there this is my data")

如果之后仍然出现错误，则可能是导入的模块之一包含（或依赖于）本机（CPython）模块，而不是纯Python。 Jython不支持前者，导入的模块必须是纯Python代码。 有关更多详细信息，请参见此相关的SO帖子 。