使用nifi executescript在python中沒有可行的替代錯誤

Question

我正在使用python腳本抓取頁面（例如facebook頁面），並希望傳遞要寫入文件的每個帖子（類似於gettwitter進程）。 我正在使用Apache Nifi ExecuteScript處理器來調用python腳本。

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

我可以成功地在處理器之間傳輸數據，但是當我嘗試添加剪貼代碼時，我總是出錯。 我正在使用python 2.7.8版本。 據我了解，executeScript在內部使用jython，而jython可以翻譯python代碼。

如果刪除與nifi相關的代碼（內部類和流文件），則以下代碼可在nifi外與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)

以下是錯誤的完整信息

> 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

感謝您的指導。 謝謝。

Answer 1

從源代碼看來，您在以下行上缺少右括號：

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

如果之后仍然出現錯誤，則可能是導入的模塊之一包含（或依賴於）本機（CPython）模塊，而不是純Python。 Jython不支持前者，導入的模塊必須是純Python代碼。 有關更多詳細信息，請參見此相關的SO帖子 。