Package edu.stanford.slac.archiverappliance.PlainPB

Class PlainPBPathNameUtility

  • public class PlainPBPathNameUtility
extends Object
    A utility class with a bunch of methods that operate on the path names used by the PlainPB storage plugin.
    Author:
    mshankar

    • Constructor Detail

      • PlainPBPathNameUtility

        public PlainPBPathNameUtility()

    • Method Detail

      • getPathsWithData

        public static Path[] getPathsWithData​(ArchPaths archPaths,
                                      String rootFolder,
                                      String pvName,
                                      Timestamp startts,
                                      Timestamp endts,
                                      String extension,
                                      PartitionGranularity granularity,
                                      PlainPBStoragePlugin.CompressionMode compressionMode,
                                      PVNameToKeyMapping pv2key)
                               throws IOException
        Given a parent folder, this method returns a list of all the paths with data that falls within the specified timeframe. We assume the pathnames follow the syntax used by the PlainPBStorage plugin. The alg for matching is based on this 
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        For the chunks that are eliminated, either the end time of the chunk is less than the start time or the start time of the chunk is greater than the end time.
        Parameters:
        archPaths - The replacement for NIO Paths
        rootFolder - The root folder for the plugin.
        pvName - Name of the PV.
        startts - Timestamp start
        endts - Timestamp end
        extension - The file extension.
        granularity - Partition granularity of the file.
        compressionMode - Compression Mode
        pv2key - PVNameToKeyMapping
        Returns:
        Path A list of all the paths
        Throws:
        IOException -  

      • getPathsBeforeCurrentPartition

        public static Path[] getPathsBeforeCurrentPartition​(ArchPaths archPaths,
                                                    String rootFolder,
                                                    String pvName,
                                                    Timestamp currentTime,
                                                    String extension,
                                                    PartitionGranularity granularity,
                                                    PlainPBStoragePlugin.CompressionMode compressionMode,
                                                    PVNameToKeyMapping pv2key)
                                             throws IOException
        The PlainPB storage plugin partitions files according to time and partition granularity. At any particular point in time, we are only writing to one partition, the "current" partition. For ETL, we need to know the partitions that are not being written into; that is, all the previous partitions. This is typically everything except the file for the current partition
        Parameters:
        archPaths - The replacement for NIO Paths
        rootFolder - The root folder for the plugin
        pvName - The name of the PV
        currentTime - The time that we are running ETL for. To prevent border conditions, caller can add a buffer if needed.
        extension - The file extension.
        granularity - The granularity of this store.
        compressionMode - Compression Mode
        pv2key - PVNameToKeyMapping
        Returns:
        Path A list of all the paths
        Throws:
        IOException -  

      • getAllPathsForPV

        public static Path[] getAllPathsForPV​(ArchPaths archPaths,
                                      String rootFolder,
                                      String pvName,
                                      String extension,
                                      PartitionGranularity granularity,
                                      PlainPBStoragePlugin.CompressionMode compressionMode,
                                      PVNameToKeyMapping pv2key)
                               throws IOException
        This method returns all the paths that could contain data for a PV sorted according to the name (which in our case should translate to time).
        Parameters:
        archPaths - The replacement for NIO Paths
        rootFolder - The root folder for the plugin
        pvName - The name of the PV
        extension - The file extension.
        granularity - The granularity of this store.
        compressionMode - Compression Mode
        pv2key - PVNameToKeyMapping
        Returns:
        Path A list of all the paths
        Throws:
        IOException -  

      • getMostRecentPathBeforeTime

        public static Path getMostRecentPathBeforeTime​(ArchPaths archPaths,
                                               String rootFolder,
                                               String pvName,
                                               Timestamp startts,
                                               String extension,
                                               PartitionGranularity granularity,
                                               PlainPBStoragePlugin.CompressionMode compressionMode,
                                               PVNameToKeyMapping pv2key)
                                        throws Exception
        If a PV changes infrequently, we often will not have a sample in the given time frame. The getData contract asks that we return the most recent known sample; even if this sample's timestamp is before the requested start/end time. The way we do this is to ask for the file that potentially has most recent data before the start time. We take advantage of the sorting nature of getAllPathsForPV and work our way from the back
        Parameters:
        archPaths - The replacement for NIO Paths
        rootFolder - The root folder for the plugin
        pvName - Name of the PV.
        startts - Timestamp start
        extension - The file extension.
        granularity - Partition granularity of the file.
        compressionMode - Compression Mode
        pv2key - PVNameToKeyMapping
        Returns:
        Path A list of all the paths
        Throws:
        Exception -  

      • getPreviousPartitionBeforeTime

        public static Path getPreviousPartitionBeforeTime​(ArchPaths archPaths,
                                                  String rootFolder,
                                                  String pvName,
                                                  Timestamp startts,
                                                  String extension,
                                                  PartitionGranularity granularity,
                                                  PlainPBStoragePlugin.CompressionMode compressionMode,
                                                  PVNameToKeyMapping pv2key)
                                           throws Exception
        If a PV changes infrequently, we often will not have a sample in the given time frame. The getData contract asks that we return the most recent known sample; even if this sample's timestamp is before the requested start/end time. Another way we do this is to return the last event in the partition which ends before the start time. We take advantage of the sorting nature of getAllPathsForPV and work our way from the back
        Parameters:
        archPaths - The replacement for NIO Paths
        rootFolder - The root folder for the plugin
        pvName - Name of the PV.
        startts - Timestamp start
        extension - The file extension.
        granularity - Partition granularity of the file.
        compressionMode - Compression Mode
        pv2key - PVNameToKeyMapping
        Returns:
        Path A list of all the paths
        Throws:
        Exception -  

      • determineTimesFromFileName

        public static edu.stanford.slac.archiverappliance.PlainPB.PlainPBPathNameUtility.StartEndTimeFromName determineTimesFromFileName​(String pvName,
                                                                                                                                 String finalNameComponent,
                                                                                                                                 PartitionGranularity partitionGranularity,
                                                                                                                                 PVNameToKeyMapping pv2key)
                                                                                                                          throws IOException
        Determines the times for a chunk simply from the file name. Bear in mind there is no guarantee that the file has data in this range. For that, @see PBFileInfo.
        Parameters:
        pvName - Name of the PV.
        finalNameComponent - The final name component
        partitionGranularity - Partition granularity of the file.
        pv2key - PVNameToKeyMapping
        Returns:
        fileNameTimes Start and End Time from name
        Throws:
        IOException -