Server mapping enables the RPC server to correctly support special Natural syntax such as REDEFINEs,
special Natural Mapping Editor operations, etc.
If one of these elements is used the IDL Extractor for Natural automatically extracts a server mapping file (Designer file
with extension .cvm)
in addition to the IDL file (interface definition language).
Also the Natural Wrapper may generate a server mapping file for RPC server generation.
The server mapping file is used at runtime to marshal and unmarshal the RPC data stream.
A server mapping file is wrapped into the client interface objects when an RPC client is generated.
Therefore, it is important the server mapping (.cvm) is available before creating any RPC client component,
that is, the server program must be extracted or generated first. This document covers the following topics:
The following rules apply to a server mapping file for Natural:
Mapping files have the extension .cvm.
The mapping file has to relate to an appropriate IDL file. Always keep the IDL file and the mapping file together in the same folder.
The mapping file is created if required by the Natural Wrapper | Extractor. See When is a Server Mapping File Required?
If an IDL file has a corresponding mapping file, at least one of the IDL programs in the IDL file requires server-mapping information to correctly call the target server. For those IDL programs, there is a server mapping (corresponding to a line) in the server mapping file.
If there is an IDL file but no corresponding mapping file, there is no IDL program that requires server mapping information.
| Natural Syntax | Natural Mapping Editor | Server Mapping Reqired | More Information |
|---|---|---|---|
REDEFINE |
yes | Extracting Natural REDEFINES in the IDL Extractor for Natural documentation
|
|
| all | Rename of program | yes | Renaming a Program |
| all | Multiple interfaces | yes | Extracting Multiple Interfaces |
| all | Set constant | yes | Setting Natural Parameters to Constants |
| all | Suppress | yes | Suppressing Natural Parameters |
| Other combinations | no | ||
| Natural Wrapper | Server Mapping Required | More Information |
|---|---|---|
| IDL program name is not a valid Natural name and is therefore adapted, or the Natural program name is customized | yes | Step 2: Customize Natural Server Names under Using the Natural Wrapper for the Server Side within NaturalONE |
Because server mapping files (Designer files with extension .cvm) contain text data only, a server mapping file is text-based (although it is not intended for human consumption). Therefore, you can include it in your source control management together with the IDL file and the Natural source(s) as a triplet that should always be kept in sync.
For server mapping files (Designer files with extension .cvm), you can use a third party file/text compare tool to check if two files are identical.
A server mapping entry (corresponding to a line in a server mapping file) contains a creation timestamp at offset 276 (decimal) in the format YYYYMMDDHHIISST. The precision is 1/10 of a second.