Apache Beam TextIO glob get original filename

问题

I have setup a pipeline. I have to parse hundreds of *.gz files. Therefore glob works quite good.

But I need the original name of the currently processed file, because i want to name the result files as the original files.

Can anyone help me here?

Here is my code.

@Default.String(LOGS_PATH + "*.gz")
String getInputFile();
void setInputFile(String value);


    TextIO.Read read = TextIO.read().withCompressionType(TextIO.CompressionType.GZIP).from(options.getInputFile());
        read.getName();

        p.apply("ReadLines", read).apply(new CountWords())
         .apply(MapElements.via(new FormatAsTextFn()))
         .apply("WriteCounts", TextIO.write().to(WordCountOptions.LOGS_PATH + "_" + options.getOutput()));

    p.run().waitUntilFinish();

回答1:

This is possible starting with Beam 2.2 using a combination of FileIO.match(), FileIO.read() and custom code to read lines of text. You can already use this at HEAD, or you can wait until release 2.2 is finalized (it's currently in progress).

PCollection<KV<String, String>> filesAndLines = 
  p.apply(FileIO.match().filepattern(...))
   .apply(FileIO.read())
   .apply(ParDo.of(new DoFn<ReadableFile, KV<String, String>>() {
     @ProcessElement
     public void process(ProcessContext c) {
       ReadableFile f = c.element();
       String filename = f.getMetadata().resourceId().toString();
       String line;
       try (BufferedReader r = new BufferedReader(Channels.newInputStream(f.open()))) {
         while ((line = r.readLine()) != null) {
           c.output(KV.of(filename, line));
         }
       }
     }
   }));

来源：https://stackoverflow.com/questions/47022853/apache-beam-textio-glob-get-original-filename