def querySolr(core: String, selectQuery: String, server: SolrClient,
            pageNum: Int, pageStart: Int, pageSize: Int): (Long, SolrDocumentList) = {
    val query = new SolrQuery(core)
    query.setQuery(selectQuery)
    query.setStart(pageStart)
    query.setRows(pageSize)
    val response: QueryResponse = server.query(query)
    val results: SolrDocumentList = response.getResults
    val total = results.getNumFound
    (total, results)
  }

  def pageCalc(page: Int, pageSize: Int, totalItems: Long): (Int, Long, Long) = {
     val from = ((page - 1) * pageSize) + 1
     val to = totalItems min (from + pageSize - 1)
     val totalPages = (totalItems / pageSize) + (if (totalItems % pageSize > 0) 1 else 0)
     (from, to, totalPages)
  }

 def getRecordsFromSolr(core: String, solrhost: String, userName: String, password: String,
                     query: String): List[SolrDocument] = {

     val startTime = System.nanoTime()
     val url = "https://" + solrhost + ":8983/solr/" + core
     val solrPort = 8983

     val builder: SSLContextBuilder = new SSLContextBuilder()
     builder.loadTrustMaterial(null, new TrustSelfSignedStrategy())
     val sslsf: SSLConnectionSocketFactory = new SSLConnectionSocketFactory(
      builder.build(),  SSLConnectionSocketFactory.ALLOW_ALL_HOSTNAME_VERIFIER
)

   val credsProvider: CredentialsProvider = new BasicCredentialsProvider()
credsProvider.setCredentials(
    new AuthScope(solrhost, solrPort),
   new UsernamePasswordCredentials(userName, password))

   val httpclient: CloseableHttpClient =HttpClients.custom().setSSLSocketFactory(sslsf).setDefaultCredentialsProvider(credsProvider).build()

  val server: SolrClient = new HttpSolrClient(url, httpclient)

   logger.info("solr connection completed")

   val pageSize = 1000
   var pageNum = 1
   var nextPage: (Int, Long, Long) = (0, 1000, 0)
   var offset: Long = 0

   var totalResult = querySolr(core, query, server, pageNum, 0, pageSize)
   var total = totalResult._1
   var results: List[SolrDocument] = totalResult._2.toList
  while (total > offset) {
    offset += pageSize
    pageNum += 1
    nextPage = pageCalc(pageNum, pageSize, total)
    totalResult = querySolr(core, query, server, pageNum, nextPage._1, pageSize)
    total = totalResult._1
    results = (results ++ totalResult._2.toList)
 }
 }