Exploring the File Adapter

With SAP Application Interface Framework, you can import and process files. A file can be uploaded using the report for uploading files. To be able to upload files, the following entities must be in place:

1. A RAW structure/DDIC structure matching the structure of the file: Create a DDIC structure representing the structure of the file. The structure must contain a structure matching the fields of the file. If the file contains a table of entries, the DDIC structure must contain a table with the structure containing the fields of the file as line type. This structure is used as the raw structure in the SAP Application Interface Framework interface.
2. An SAP structure defined by the processing functions in the system: Create or reuse an SAP structure. The subsequent processing within the SAP Application Interface Framework determines the creation or reuse of an SAP structure.
3. An SAP Application Interface Framework interface: Set interface engines. The Application and Persistence Engines are set to XML. The Selection Engine is set to Index Tables, and the Logging Engine uses the Application Log.
4. Define structure mappings and actions: Map the RAW to the SAP structure, trigger the follow-up process structure, and trigger the follow-up process.
5. A file adapter configuration: Create the file adapter configuration. There are no default settings for uploading a file. To read a file from the system, the minimum information required is the file type, file content, and text type. To map the file to the interface, the structure name and the field name, where the file content is moved to during the upload, is required.

The imported file results in one or more SAP Application Interface Frameworks messages. The mapping of the file content to one or multiple SAP Application Interface Framework messages relies on the file adapter configuration, interface/structure settings, and upload parameters.

Every SAP Application Interface Framework interface requires source and destination DDIC structures. A file does not have a corresponding DDIC structure. How do you create this structure?

To determine the correct destination structure, you must have a look at the functions processing the file in the SAP system. To come to a correct destination structure, the processing functions/BAPIs have to be analyzed. The destination structure must contain the tables/structures that the follow-up processing requires.

The destination structure must contain tables/structures that are required in the follow-up processing of the message.

1. Identify the required parameters to define the correct destination structure.
2. Create a corresponding DDIC structure. Add all required structures/tables that are used as parameters in the processing functions/BAPIs, to the destination structure.
3. Add all required structures/tables that are used as parameters in the processing functions/BAPIs, to the destination structure.

There are two different reports to upload files in the SAP Application Interface Framework:

1. File Upload: This transaction allows you to upload single files from either the application server or from a local PC. It's targeted at users that must upload files manually. The report provides the option to display the file after upload so that the user can have a look at its content. Furthermore, if you have a flat structure, you can display the result structure before the data is transferred to the SAP Application Interface Framework. This way, you can see how the data was mapped from the file to the structure specified in the file adapter configuration.

   Transaction: /AIF/LFA_UPLOAD_FILE

2. Mass File Upload from Server: This transaction allows you to upload multiple files from the application server. The report can be scheduled as a regular job to read data from a predefined path and pass it to the SAP Application Interface Framework. Once a file has been read, it's moved to a new folder on the application server to avoid having the same files read again. This folder can also be specified.

   Transaction: /AIF/LFA_CHECK_SEND

To upload a file, you must specify:

• The file adapter configuration, a directory, or logical file from where the file is uploaded.
• A block size in lines.
• A runtime configuration group.

1. File Type: Defines whether the file should be read in binary mode or in text mode.
2. File Content: Defines what the content of the file looks like. Depending on the selection done in the File Content field, different fields are displayed in the Customizing of the field adapter configuration. These are the following file content types:
   • Flat Structure.
   • Complex Structure: The file content can be mapped into a complex structure, which may contain header, substructures, and sub tables. In this case, you have to maintain a substructure determination in Customizing for the SAP Application Interface Framework under Configure File Adapter.
   • User-defined: Customer-specific mapping can be done using a customer-specific function module, the name of which has to be stored in the Mapping Function field.
   • XML: Mapping is done via Extensible Stylesheet Language Transformation (XSLT) or Simple Transformation (ST). The transformation name must be stored in the Transformation field.
3. Text Type: Defines where the file content should be separated into individual fields during the file upload. The following options are possible:
   • Special Character as Separator: The individual fields are separated by a special character in the file (for example, if there are CSV files). The separator must be maintained in the Field Separator field.
   • Fixed Field Lengths: The length of the individual fields is correctly represented in the file and no special field separator is used.
   • One Field per Line: Each field has exactly one line in the file.
4. Structure Name: Name of the raw structure used in the SAP Application Interface Framework interface.
5. Field Name: Defines the component of the structure, maintained in the Structure Name field, to where the file content is moved during upload. This component can also be a table type. In this case, the line type of this table type has to fit to the data that you upload with the file.