How to invoke SAP RFC function by external program with nwrfcsdk

Catalogue

1. 1. cpp invoke nwrfc sdk
   1. 1.1. String convert
      1. 1.1.1. sap uc to wxString
      2. 1.1.2. wxString to sap uc
      3. 1.1.3. Establish a pool class to store the dataset from the result of RFC Function
      4. 1.1.4. C++ class to communicate with RFC Function
      5. 1.1.5. sample - how to use this class to invoke the rfc function
         1. 1.1.5.1. this is rfc function def
2. 2. Python invoke RFC Function
3. 3. Reference

cpp invoke nwrfc sdk

The whole code is in my gist
nwrfc sdk , you can git download from here

String convert

sap uc to wxString

 wxString sapucTostring(SAP_UC * s_ucs, int length)
{
  RFC_RC rc;
  RFC_ERROR_INFO errorInfo;

  wxString str;

  if(length==0)
    return wxEmptyString;

  if(length == -1)
     length = strlenU(s_ucs);


  unsigned int utf8Size = length * 2;
  char *utf8 = (char*) malloc(utf8Size + 1);
  utf8[0] = '\0';

  unsigned int resultLen = 0;
  rc = RfcSAPUCToUTF8(s_ucs, length, (RFC_BYTE*) utf8, &utf8Size, &resultLen, &errorInfo);

  int i=0;

  while (rc != RFC_OK) {
    // TODO: throw wrapError
        if(rc==RFC_BUFFER_TOO_SMALL)
        {
            i+=8;
            utf8Size = (length+i) * 2;
            free(utf8);

            utf8 = (char*) malloc(utf8Size + 1);
            utf8[0] = '\0';
            rc = RfcSAPUCToUTF8(s_ucs, length, (RFC_BYTE*) utf8, &utf8Size, &resultLen, &errorInfo);

        }
        else
        {
            errorHandling(rc, cU("sap uc to string"), &errorInfo, NULL);
            return "error";
        }
  }

  str = wxString(utf8,wxConvUTF8);

  free(utf8);

  return str;

}

wxString to sap uc

SAP_UC * stringTosapuc(wxString &str)
{

  RFC_RC rc;
  SAP_UC *sapuc;
  unsigned int sapucSize, resultLen = 0;

  RFC_ERROR_INFO errorInfo;

  const char *cStr = str.mb_str(wxConvUTF8);

  sapucSize = strlen(cStr) + 1;

  sapuc = mallocU(sapucSize);
  memsetU(sapuc, 0, sapucSize);
  rc = RfcUTF8ToSAPUC((RFC_BYTE*)cStr, strlen(cStr), sapuc, &sapucSize, &resultLen, &errorInfo);

  if (rc != RFC_OK) {
    // FIXME: error handling
    errorHandling(rc, cU("string to sap_uc"), &errorInfo, NULL);
    return cU("error");

  }

   return sapuc;
}

Establish a pool class to store the dataset from the result of RFC Function

class Str_Line
{
public:
	Str_Line()
	{
		cols = 0; //columns label ptr
		num_cols=0;//column's quantity
	}

	Str_Line(int _col_num)
	{
	    num_cols = _col_num;
        if(_col_num >0)
	        cols = new wxString[num_cols];
	}

	~Str_Line()
	{
		if (cols) delete[] cols;
	}

	wxString *cols;
	int num_cols;
};


class Value_Pool
{
public:
	Value_Pool(int initialLines, bool _dic=false);
	~Value_Pool();
	Str_Line *operator[] (int line)
	{
		return Get_Value(line);
	}
	Str_Line *Get_Value(int lineNo);

	Str_Line *Get_Name()
	{
	    return ptr_name;
	}
	void Delete(int lineNo);

	wxString get_value_by_name(wxString str, Str_Line* p_str);
	wxString get_value_by_index(int i_col, Str_Line* p_str);
	int find_col_name(wxString str);
	int Find_row_value(wxString str, int i_col, int i_start=0);
	wxArrayInt find_row_value_array(wxString str, int i_col, int i_start=0);
	int Get_Same_Count(wxString str, int i_col);


	bool is_dict()
	{
	    return is_dic;
	}

	int GetNumOfRows()
	{
	    return num_rows;
	}

private:
    Str_Line * ptr_name;// store the headers
	Str_Line **ptr_value;// store the values
    bool is_dic;
	int num_rows;

};

C++ class to communicate with RFC Function

Because in sap, all rfc function is based on the inner table to run. If you invoke the rfc function , first , you must fill the cases in the import table(inner table), then run the function , at last, get the result in the export table(inner table).

class Rfc_Communication
{
public:
    Rfc_Communication();
    virtual ~Rfc_Communication();

    RFC_FUNCTION_HANDLE Create_Function(wxString function_name,RFC_FUNCTION_DESC_HANDLE& funhandle_desc);
    RFC_RC fillFunctionParameter(RFC_FUNCTION_DESC_HANDLE funcDesc, RFC_FUNCTION_HANDLE container, wxString v_name, Value_Pool * v_value);//list cases fill
    RFC_RC fillFunctionParameter(RFC_FUNCTION_DESC_HANDLE funcDesc, RFC_FUNCTION_HANDLE container, wxString v_name, wxString s_value);//single case fill
    RFC_RC RunFunction(RFC_FUNCTION_HANDLE fun_handle);
    RFC_RC DestroyFunction(RFC_FUNCTION_HANDLE fun_handle);
    Value_Pool* GetResult(wxString result_name, RFC_FUNCTION_DESC_HANDLE fun_handle_desc, RFC_FUNCTION_HANDLE fun_handle);
    RFC_RC rfc_connect(); 
    void rfc_closed();
    bool rfc_check_connect();

    wxString str_result;

protected:
private:

    RFC_CONNECTION_HANDLE connection;
    RFC_ERROR_INFO errorInfo;

    SAP_UC* fillString(wxString str);
    wxString wrapString(SAP_UC * uc,int length =-1, bool rstrip=false);

    RFC_RC lookupMetaData(wxString function_name,RFC_FUNCTION_DESC_HANDLE &funhandle_desc);
    RFC_RC fillVariable(RFCTYPE typ, RFC_FUNCTION_HANDLE container, SAP_UC* cName, Value_Pool * v_value, wxString str, RFC_TYPE_DESC_HANDLE typeDesc);
    RFC_RC fillStructureField(RFC_TYPE_DESC_HANDLE typeDesc, RFC_STRUCTURE_HANDLE container, SAP_UC * name, wxString s_value);
    RFC_RC fillTable(RFC_TYPE_DESC_HANDLE typeDesc, RFC_TABLE_HANDLE container, Value_Pool* value);
    RFC_RC fillField(RFCTYPE typ, DATA_CONTAINER_HANDLE container, SAP_UC* name, wxString s_value);

    Value_Pool* wrapResult(RFC_FUNCTION_DESC_HANDLE functionDescHandle, RFC_FUNCTION_HANDLE functionHandle, wxString varial_name, bool rstrip=false);
    void wrapStructure(RFC_TYPE_DESC_HANDLE typeDesc, RFC_STRUCTURE_HANDLE structHandle, Str_Line* line_value=NULL,bool _withname=false, Str_Line* line_name=NULL, bool rstrip=false);
    Value_Pool* wrapVariable(RFCTYPE typ, RFC_FUNCTION_HANDLE functionHandle, SAP_UC* cName, unsigned int cLen, RFC_TYPE_DESC_HANDLE typeDesc, bool rstrip=false);
    wxString wrapField(RFCTYPE typ, RFC_STRUCTURE_HANDLE functionHandle, SAP_UC* cName, unsigned int cLen, bool rstrip=false);

};

sample - how to use this class to invoke the rfc function

this is rfc function def

Function id : ZAP_PS_MATERIAL_INFO
import: IT_CE_MARA

field id	type	length	decimal	description
MATNR	CHAR	18		Material Number
WERKS	CHAR	4		Plant

CE_SPRAS

field id	type	length	decimal	description
Language	CHAR	1		Language Key

export: OT_CE_MARA

field id	type	length	decimal	description
MATNR	CHAR	18	0	Material Number
MAKTG	CHAR	40	0	Material description in upper case for matchcodes
MAKTX	CHAR	40	0	Material Description (Short Text)
SPRAS	LANG	1	0	Language Key
BRGEW	QUAN	13	3	Gross Weight
MEINS	UNIT	3	0	Base Unit of Measure
MTART	CHAR	4	0	Material Type
NORMT	CHAR	18	0	Industry Standard Description (such as ANSI or ISO)
BISMT	CHAR	18	0	Old material number
ZEINR	CHAR	22	0	Document number (without document management system)
GROES	CHAR	32	0	Size/dimensions
LGFSB	CHAR	4	0	Default storage location for external procurement
LGPRO	CHAR	4	0	Issue Storage Location
DISPO	CHAR	3	0	MRP Controller (Materials Planner)
SBDKZ	CHAR	1	0	Dependent requirements ind. for individual and coll. reqmts
FEVOR	CHAR	3	0	Production scheduler
SOBSK	CHAR	2	0	Special Procurement Type for Costing
BESKZ	CHAR	1	0	Procurement Type
SOBSL	CHAR	2	0	Special procurement type
MATGR	CHAR	20	0	Group of Materials for Transition Matrix
MFRGR	CHAR			Material freight group
WERKS	CHAR	4	0	Plant
VPRSV	CHAR	1	0	Price control indicator
BWTAR	CHAR	10	0	Valuation Type
BWKEY	CHAR	4	0	Valuation Area
BKLAS	CHAR	4	0	Valuation Class
TDLINE	CHAR	255	0	Material master Basic Data Text

As above, the IT_CE_MARA, CE_SPRAS, OT_CE_MARA are structure.

Invoke code

void rfctestDialog::OnButton1Click(wxCommandEvent& event)
{
    if(!sap_conn->rfc_check_connect())
        sap_conn->rfc_connect();

    Value_Pool* mat_value=new Value_Pool(1, true); // this is filled innner table

    Str_Line * line= mat_value->Get_Name();

    line->cols= new wxString[2];
    line->num_cols = 2;
    wxString str = "MATNR";

    line->cols[0] = str;

    str = "WERKS";
    line->cols[1] = str;

    line = mat_value->Get_Value(0);
    line->num_cols = 2;

    line->cols = new wxString[2];

    str = "330040240";
  //  str = "200000051";
    line->cols[0] = str;

    str = "2101";
    line->cols[1] = str;
    wxString s_lang = "1";


    Value_Pool * pool_result;


    RFC_FUNCTION_DESC_HANDLE fun_handle_desc;
    RFC_FUNCTION_HANDLE fun_handle;


    fun_handle = sap_conn->Create_Function(wxT("ZAP_PS_MATERIAL_INFO"),fun_handle_desc);
    sap_conn->fillFunctionParameter(fun_handle_desc,fun_handle,wxT("IT_CE_MARA"),mat_value);//fill query table 
    sap_conn->RunFunction(fun_handle);
    pool_result = sap_conn->GetResult(wxT("OT_CE_MARA"),fun_handle_desc,fun_handle);//get result table

    sap_conn->DestroyFunction(fun_handle);

    if(pool_result)
    {
        int i_row = pool_result->GetNumOfRows();
        str.Empty();

        Str_Line* line_head= pool_result->Get_Name();

        for(int i=0; i<i_row; i++)
        {
            Str_Line * line = pool_result->Get_Value(i);

            int i_col = line->num_cols;

            for(int j=0; j<i_col; j++)
            {
                str = str+line_head->cols[j]+wxT(":")+line->cols[j]+wxT("\n");
            }
        }
    }

    tc_result->SetValue(str);

}

Python invoke RFC Function

This must install the pyRFC.
How to intall it , you can according to link
How to invoke it :

...
import pyrfc
...
        
    def check_in_sap(self):
        self.nstd_mat_list=[]
        self.nstd_app_id=''
        self.hibe_mats=[]
        
        '''
        read the user and login parameters from a cfg file
        '''
        logger.info("logining in SAP...")
        config = ConfigParser()
        config.read('sapnwrfc.cfg')
        para_conn  = config._sections['connection']
        para_conn['user'] = base64.b64decode(para_conn['user']).decode()
        para_conn['passwd'] = base64.b64decode(para_conn['passwd']).decode()
        mats = self.mat_items.keys()
        
        try:
            conn = pyrfc.Connection(**para_conn)
            
            imp = []
            for mat in mats: #loop to fill the query list 
                line = dict(MATNR=mat, WERKS='2101')
                imp.append(line)
            
            logger.info("正在调用RFC函数...")
            result = conn.call('ZAP_PS_MATERIAL_INFO', IT_CE_MARA=imp, CE_SPRAS='1')
            
            std_mats=[]
            for re in result['OT_CE_MARA']: #loop to read the result line
                std_mats.append(re['MATNR'])
                
                if re['BKLAS']=='3030' and re['MATNR'] not in self.hibe_mats:
                    self.hibe_mats.append(re['MATNR'])
                
            for mat in mats:
                if mat not in std_mats:
                    logger.info("标记非标物料:"+mat)
                    self.nstd_mat_list.append(mat)
                    self.mark_nstd_mat(mat, True)
                else:
                    self.mark_nstd_mat(mat, False)
                    
            logger.info("非标物料确认完成，共计"+str(len(self.nstd_mat_list))+"个非标物料。")
            
        except pyrfc.CommunicationError:
            logger.error("无法连接服务器")
            return -1
        except pyrfc.LogonError:
            logger.error("无法登陆，帐户密码错误！")
            return -1
        except (pyrfc.ABAPApplicationError, pyrfc.ABAPRuntimeError):
            logger.error("函数执行错误。")
            return -1
        
        conn.close()
                   
        return len(self.nstd_mat_list)

Reference

1. node-rfc: https://github.com/SAP/node-rfc
2. pyRFC: https://github.com/SAP/PyRFC

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