Data Transformation Engine Services Guide

Chapter 14 – Resource Manager Component of Mercator Command Server
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Chapter 14 – Resource Manager
Component of Mercator
Command Server
The Resource Manager component of Mercator Command Server manages the
execution of the adapter since an awareness of current map execution status is required.
The Resource Manager keeps lists of adapter connections and tracks the following
information:
♦ Resource type – the type of adapter; for example, MQSeries, FTP
♦ Pointer to resource specific parameter structure - each adapter returns this
adapter-specific block of parameters on the ‘Validate Command’ call. It would
contain those parameters that must be compared to determine whether a connection
can be reused or not (for example, for the sample useradpter, the service name and
the hostname)
♦ Pointer to resource specific context structure – this structure maintains the context
handles for the connection (for example, for the sample adapter useradpter, the socket
number, the service entry, and the host entry)
♦ Connection Number – a unique number identifying the connection
Establishing A Connection
The following description shows how the Resource Manager establishes a connection.
Assume that maps have already been launched and connections are therefore open prior
to this.
3. A connection is required for resource type XYZ. Call the adapter’s “Validate
Command” function to convert the command line to an adapter-specific parameter
block.
4. Call the adapter's "Compare Connections" function with the stored adapter-specific
parameter block and the one returned from step 1.
5. If the adapter indicates that the resource matches, the connection can be reused.
6. If it does not match, then try the next in the list.
7. If still none are found, create a new element in the map list.
Termination of Connections
A connection is broken on completion of a single map. In the case where multiple maps
are being run through a “command file,” the connections are broken upon completion of
the last map.