I found below code here Pdf to elastic search,
the code extracts pdf and put into elastic search

import PyPDF2
import re
import requests
import json
import os
from datetime import date

class ElasticModel:

    name = ""
    msg = ""

    def toJSON(self):
        return json.dumps(self, default=lambda o: o.__dict__, 
            sort_keys=True, indent=4)

def __readPDF__(path):
    # pdf file object
    # you can find find the pdf file with complete code in below
    pdfFileObj = open(path, 'rb')
    # pdf reader object
    pdfReader = PyPDF2.PdfFileReader(pdfFileObj)
    # number of pages in pdf
    print(pdfReader.numPages)
    # a page object
    pageObj = pdfReader.getPage(0)
    # extracting text from page.
    # this will print the text you can also save that into String
    line = pageObj.extractText() 
    line = line.replace("\n","")
    print(line)
    return line


#line = pageObj.extractText()

def __prepareElasticModel__(line, name):
    eModel = ElasticModel();

    eModel.name = name
    eModel.msg = line
    return eModel


def __sendToElasticSearch__(elasticModel):
    print("Name : " + str(eModel))

############################################
####  #CHANGE INDEX NAME IF NEEDED
#############################################
    index = "samplepdf"

    url = "http://localhost:9200/" + index +"/_doc?pretty"
    data = elasticModel.toJSON()
    #data = serialize(eModel)
    response = requests.post(url, data=data,headers={
                    'Content-Type':'application/json',
                    'Accept-Language':'en'

                })
    print("Url : " + url)
    print("Data : " + str(data))

    print("Request : " + str(requests))
    print("Response : " + str(response))


#################################
#Change pdf dir path
###################################
pdfdir = "C:/Users/abhis/Desktop/TemplatesPDF/SamplePdf"

listFiles = os.listdir(pdfdir)
for file in listFiles :
    path = pdfdir + "https://stackoverflow.com/" + file
    print(path)

    line = __readPDF__(path)
    eModel = __prepareElasticModel__(line, file)
    __sendToElasticSearch__(eModel)

The above code is extracting the sample pdf

From above sample pdf, few fields (Such as Name and Msg) has been extracted using regex and inserted into elastic search, Hope this would help