Interface PostProcessor

    • Method Summary

      Modifier and Type Method Description
      long estimateMemoryConsumption​(String pvName, PVTypeInfo typeInfo, Timestamp start, Timestamp end, javax.servlet.http.HttpServletRequest req)
      Estimate the amount of memory required for the data generated by the post processors.
      String getExtension()
      This is the full form of the identity for the post processor and includes any parameters for the post processor.
      String getIdentity()
      The string used by clients to identify this post processor when making retrieval requests.
      void initialize​(String userarg, String pvName)
      Initialize this post processor for the given PV and request parameters.
      Callable<EventStream> wrap​(Callable<EventStream> callable)
      Primary data generation method.
    • Method Detail

      • getIdentity

        String getIdentity()
        The string used by clients to identify this post processor when making retrieval requests. For example to identify the FirstSamplePP postprocessor, users would add a pp=firstSample to the request for data. The situation is a little more complex; if a post processor has parameters then it needs to combine these into a string and offer that as an extension. The identity is just the starting part of this.
        1. For example, pp=firstSample_600 asks the server to sparsify with an interval of 600 seconds.
        2. identity is firstSample.
        3. extension is firstSample_600.
        4. User specifies firstSample_600.
        5. ETL caches the data as firstSample_600 if asked to.
        Returns:
        identify  
      • getExtension

        String getExtension()
        This is the full form of the identity for the post processor and includes any parameters for the post processor. The exact format and interpretation of this is left to the post processor; however the convention is to use underscores to separate the params and have them in a specific order.
        Returns:
        extension  
        See Also:
        getIdentity()
      • initialize

        void initialize​(String userarg,
                        String pvName)
                 throws IOException
        Initialize this post processor for the given PV and request parameters.
        Parameters:
        userarg - This is the full form (extension) of the identity for the post processor.
        pvName - The name of PV
        Throws:
        IOException -  
      • estimateMemoryConsumption

        long estimateMemoryConsumption​(String pvName,
                                       PVTypeInfo typeInfo,
                                       Timestamp start,
                                       Timestamp end,
                                       javax.servlet.http.HttpServletRequest req)
        Estimate the amount of memory required for the data generated by the post processors.
        Parameters:
        pvName - The name of PV
        typeInfo - PVTypeInfo
        start - Timestamp
        end - Timestamp
        req - HttpServletRequest
        Returns:
        Estimated Memory comsumption
      • wrap

        Callable<EventStream> wrap​(Callable<EventStream> callable)
        Primary data generation method. Using the event stream provided, do your magic and generate processed data
        Parameters:
        callable -  
        Returns:
        EventStream