空解析器和Tika服务器模式

Question

我很难理解解析器是如何加载到Tika中的。从他们的文档中可以看出，Tika-app预装在解析器(https://tika.apache.org/1.17/gettingstarted.html)中。但是，当我运行此命令来启动服务器时

    ./.java-buildpack/open_jdk_jre/bin/java -jar ./lib/tika-app-1.24.1.jar -s --port ${PORT}

    2020-11-02T13:30:26.04-0600 [APP/PROC/WEB/0] ERR Nov 02, 2020 7:30:26 PM org.apache.tika.config.InitializableProblemHandler$3 handleInitializableProblem
   2020-11-02T13:30:26.04-0600 [APP/PROC/WEB/0] ERR WARNING: J2KImageReader not loaded. JPEG2000 files will not be processed.
   2020-11-02T13:30:26.04-0600 [APP/PROC/WEB/0] ERR See https://pdfbox.apache.org/2.0/dependencies.html#jai-image-io
   2020-11-02T13:30:26.04-0600 [APP/PROC/WEB/0] ERR for optional dependencies.
   2020-11-02T13:30:26.53-0600 [APP/PROC/WEB/0] ERR Nov 02, 2020 7:30:26 PM org.apache.tika.config.InitializableProblemHandler$3 handleInitializableProblem
   2020-11-02T13:30:26.53-0600 [APP/PROC/WEB/0] ERR WARNING: org.xerial's sqlite-jdbc is not loaded.
   2020-11-02T13:30:26.53-0600 [APP/PROC/WEB/0] ERR Please provide the jar on your classpath to parse sqlite files.
   2020-11-02T13:30:26.53-0600 [APP/PROC/WEB/0] ERR See tika-parsers/pom.xml for the correct version.
   2020-11-02T13:30:26.80-0600 [APP/PROC/WEB/0] OUT Successfully started tika-app's server on port: 8080
   2020-11-02T13:30:26.80-0600 [APP/PROC/WEB/0] ERR WARNING: The server option in tika-app is deprecated and will be removed
   2020-11-02T13:30:26.80-0600 [APP/PROC/WEB/0] ERR by Tika 2.0 if not shortly after Tika 1.14.
   2020-11-02T13:30:26.80-0600 [APP/PROC/WEB/0] ERR Please migrate to the JAX-RS tika-server package.
   2020-11-02T13:30:26.80-0600 [APP/PROC/WEB/0] ERR See https://wiki.apache.org/tika/TikaJAXRS for usage.
   2020-11-02T13:31:25.66-0600 [HEALTH/0] ERR Failed to make HTTP request to '/version' on port 8080: timed out after 1.00 seconds
   2020-11-02T13:31:25.66-0600 [CELL/0] ERR Timed out after 1m0s: health check never passed.

我有最新的tika版本1.24.1。他们的文档提到了下载tika-server并在运行时传递类路径以指向tika-parsers.jar (https://cwiki.apache.org/confluence/display/TIKA/Troubleshooting+Tika#TroubleshootingTika-ParsersMissing)，但是我在任何地方都找不到parsers.jar文件。我使用openjdk-jre-1.8.0来运行它。

Answer 1

默认情况下，解析器应该捆绑在一起。服务器模式下的Tika App (-s)是基于socket的服务器。您可以通过使用netcat并查看是否得到响应来确认它是否正常工作：

nc localhost 8080 -q2 < test.pdf

要在Python中使用它，您需要编写定制代码，打开套接字并发送输入，发送SHUT_WR，然后读回输出。

如果你正在使用tika-python库，它应该使用tika-server JAR中的Tika Server，而不是tika-app JAR。它有一些帮助器设置，因此您可以指向JAR，或者您可以托管自己的实例(自运行或docker)并为其提供URL。