参考 webmagic http://webmagic.io 撸的 [scala + akka] 爬虫

• 爬虫例子 [爬知乎R大 JVM 回答]

  package io.github.wtog.example
  
  import io.github.wtog.processor.{ Page, PageProcessor, RequestSetting }
  
  import scala.concurrent.duration._
  
  // 爬虫解析逻辑
  case class ZhihuAnswerPageProcessor() extends PageProcessor {
  
    val link = "https://www.zhihu.com/api/v4/members/rednaxelafx/answers?include=data%5B*%5D.is_normal%2Cadmin_closed_comment%2Creward_info%2Cis_collapsed%2Cannotation_action%2Cannotation_detail%2Ccollapse_reason%2Ccollapsed_by%2Csuggest_edit%2Ccomment_count%2Ccan_comment%2Ccontent%2Cvoteup_count%2Creshipment_settings%2Ccomment_permission%2Cmark_infos%2Ccreated_time%2Cupdated_time%2Creview_info%2Cquestion%2Cexcerpt%2Cis_labeled%2Clabel_info%2Crelationship.is_authorized%2Cvoting%2Cis_author%2Cis_thanked%2Cis_nothelp%2Cis_recognized%3Bdata%5B*%5D.author.badge%5B%3F(type%3Dbest_answerer)%5D.topics&offset=0&limit=10&sort_by=created"
  
    override def doProcess(page: Page): Unit = {
      val result = page.json[Map[String, Any]]()
  
      result.get("data").foreach { answers =>
        answers.asInstanceOf[List[Map[String, Any]]].foreach { answer =>
          val question      = answer("question").asInstanceOf[Map[String, String]]("title")
          val answerContent = answer("content")
          page.addPageResultItem(Map("question" -> question, "answer" -> answerContent))
        }
      }
  
      val nextPage = result("paging").asInstanceOf[Map[String, String]].get("next")
  
      nextPage.foreach { url =>
        page.addTargetRequest(url.replaceAll("https://www.zhihu.com", "$0/api/v4"))
      }
    }
  
    override def requestSetting: RequestSetting =
      RequestSetting(
        domain = "www.zhihu.com",
        sleepTime = 3 seconds
      )
  
    override def targetUrls: List[String] = List(link)
  
    override def cronExpression: Option[String] = None
  }
  
  // 启动爬虫
  Spider(pageProcessor = ZhihuAnswerPageProcessor()).start()

  更多例子

• sbt

  1. sbt 'project example; assembly' # 打 jar 包
  2. java -jar crawler-example/target/scala-2.12/web-crawler-assembly.jar

• docker

  1. build

     sh docker/build.sh
     

  2. start container

     docker run -it --name web-crawler wtog/web-crawler:latest