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https://issues.apache.org/jira/browse/TIKA-456?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12885507#action_12885507
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Jukka Zitting commented on TIKA-456:
------------------------------------

BTW, it might be a useful extension to optionally exclude the time spent 
reading the input stream or delivering SAX events from the time reserved to the 
parsing process. This way you can prevent things like slow network connections 
or non-responsive backend databases from causing a parser timeout.

> Support timeouts for parsers
> ----------------------------
>
>                 Key: TIKA-456
>                 URL: https://issues.apache.org/jira/browse/TIKA-456
>             Project: Tika
>          Issue Type: Improvement
>            Reporter: Ken Krugler
>            Assignee: Chris A. Mattmann
>
> There are a number of reasons why Tika could hang while parsing. One common 
> case is when a parser is fed an incomplete document, such as what happens 
> when limiting the amount of data fetched during a web crawl.
> One solution is to create a TikaCallable that wraps the Tika   parser, and 
> then use this with a FutureTask. For example, when using a ParsedDatum POJO 
> for the results of the parse operation, I do something like this:
>     parser = new AutoDetectParser();
>     Callable<ParsedDatum> c = new TikaCallable(parser, contenthandler, 
> inputstream, metadata);
>     FutureTask<ParsedDatum> task = new  FutureTask<ParsedDatum>(c);
>     Thread t = new Thread(task);
>     t.start();
>     ParsedDatum result = task.get(MAX_PARSE_DURATION, TimeUnit.SECONDS);
> And TikaCallable() looks like:
> class TikaCallable implements Callable<ParsedDatum> {
>     public TikaCallable(Parser parser, ContentHandler handler, InputStream 
> is, Metadata metadata) {
>         _parser = parser;
>         _handler = handler;
>         _input = is;
>         _metadata = metadata;
>         ...
>     }
>     public ParsedDatum call() throws Exception {
>         ....
>         _parser.parse(_input, _handler, _metadata, new ParseContext());
>         ....
>     }
> }
> This seems like it would be generally useful, as I doubt that we'd  ever be 
> able to guarantee that none of the parsers being wrapped by Tika could ever 
> hang.
> One idea is to create a TimeoutParser that wraps a regular Tika Parser. E.g. 
> something like:
>   Parser p = new TimeoutParser(new AutodetectParser(), 20, TimeUnit.SECONDS);
> Then the call to p.parse(...) would create a Callable (similar to the code 
> above) and use the specified timeout when calling task.get().
> One minus with this approach is that it creates a new thread for each parse 
> request, but I don't think the thread overhead is significant when compared 
> to the typical parser operation.

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