Creation of Custom IDOc type and message Type

First Create Partner Profile(WE20 Tcode) and Port Definition in WE19 Tcodes.
Get the Basis help to create them.

1. First create segments in WE31 Tcode with the required dataelements
2. Create the Basic Idoc Type in WE30
    Release the Segments and IDOC type.
3. Create Message type in We81
4  Assign the message type to IDOC type in WE82 T code
5. Create the process code in We41 (for Outbound) WE42 (for Inbound)
6. Create A fun module in SE37 starting with ZIDOC_OUTPUT_.. by copying some Inbound (for Inbound) Outbound Fun module
7.Create Workflow setting if needed ..
8. Assign the fun module to Idoc Type, Message Type and WF object (if it is there0
9. Define setting for fun module in BD51
10. In BD51 Define the settings for Fun module..
11. Assign the Processs Code to Fun mod`ule

Outbound:
Step 
1. Application document is created when transaction is saved.
2. Message control is invoked.
3. Messages are processed by system.
4. Messages are Edited (if desired).
5. Output (ALE / EDI) is checked
6. Validate against Message control record from Partner Profile
7. Application Document is saved.
8. Entry NAST table is created for every selected output program along with Medium & Timing.
9. Check for Process Immediately .
If (yes)
Determine Processing Program from TNAPR Table.
ELSE
Execute RSNASTED Program.
10. Read Partner Profile to determine Process Code.
11. Process Code points to the Function Module & Invoked.
12. IDoc is generated. 
13. Check for ALE Request.
if (Yes)
Perform Filters, Conversions, Version Changes etc.
Else.
IDoc is stored in DATABASE.

Inbound:
Step
1. EDI Subsystem creates an IDoc file from EDI Messages
2. Subsystem calls Functional Module EDI_DATA_INCOMING from startRFC program.
3. Data in Control Record is validate against the Partner Profile.
4. IDoc is generated in Database and syntax check is carried out.
5. IDoc file is deleted once file read.
6. Event PROCESSSTATE REACHED is triggered in Idoc Object Workflow. 
7. Check for Process Immediately.
If NO
Execute RBDAPP01 Program
Else
Read Process Code from Partner Profile 
Process Code Points to Function Module
Application Document Posted. 

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