如何在ODATA服务中返回错误MESSAGE

我们在写ABAP代码时，出要返回错误消息，我们一般写

MESSAGE '条码内容为空!' TYPE 'E'.
MESSAGE '条码内容为空!' TYPE 'I'.

1 2	MESSAGE '条码内容为空!' TYPE 'E'. MESSAGE '条码内容为空!' TYPE 'I'.

之类的错误代码返回错误消息，但在ODATA的类中，如直接这样写的话，那在ODATA的返回只会说是在/IWFND/ERROR_LOG 中可查询错误，错误如下

<error xmlns="http://schemas.microsoft.com/ado/2007/08/dataservices/metadata">
<code>0050569259751EE4BA9710043F8A5115</code>
<message xml:lang="zh">In the context of Data Services an unknown internal server error occurred</message>
<innererror xmlns="http://schemas.microsoft.com/ado/2007/08/dataservices/metadata">
<transactionid>42AB5881078F0090E005EE19D9BDF0BF</transactionid>
<timestamp>20200819010457.1021360</timestamp>
<Error_Resolution>
<SAP_Transaction>For backend administrators: use ADT feed reader "SAP Gateway Error Log" or run transaction /IWFND/ERROR_LOG on SAP Gateway hub system and search for entries with the timestamp above for more details</SAP_Transaction>
<SAP_Note>See SAP Note 1797736 for error analysis (https://service.sap.com/sap/support/notes/1797736)</SAP_Note>
</Error_Resolution>
</innererror>
</error>

<message xml:lang="zh">In the context of Data Services an unknown internal server error occurred</message>

<Error_Resolution>

<SAP_Transaction>For backend administrators: use ADT feed reader "SAP Gateway Error Log" or run transaction /IWFND/ERROR_LOG on SAP Gateway hub system and search for entries with the timestamp above for more details</SAP_Transaction>

<SAP_Note>See SAP Note 1797736 for error analysis (https://service.sap.com/sap/support/notes/1797736)</SAP_Note>

</Error_Resolution>

</innererror>

</error>

而事实上我们想返回的错误是最终用户看的，此满足不了我们的需求，所以需要对返回错误内容进行修改。

原文地址：https://www.saplearners.com/map-message-odata-response-header-sap-message/

1.说明

SAP官方建议的是把错误消息放入OData response header parameter “sap-message”

2.ODATA中错误的写法

*1. Instatiate the Message Container
    DATA: lo_message_container TYPE REF TO /iwbep/if_message_container.

    CALL METHOD me->/iwbep/if_mgw_conv_srv_runtime~get_message_container
      RECEIVING
        ro_message_container = lo_message_container.

    CALL METHOD lo_message_container->add_message
      EXPORTING
        iv_msg_type               = /iwbep/cl_cos_logger=>warning
        iv_msg_id                 = 'ZTEST'
        iv_msg_number             = '000'
        iv_add_to_response_header = abap_true. "add the message to the header

*1. Instatiate the Message Container

DATA: lo_message_container TYPE REF TO /iwbep/if_message_container.

CALL METHOD me->/iwbep/if_mgw_conv_srv_runtime~get_message_container

RECEIVING

ro_message_container = lo_message_container.

CALL METHOD lo_message_container->add_message

EXPORTING

iv_msg_type = /iwbep/cl_cos_logger=>warning

iv_msg_id = 'ZTEST'

iv_msg_number = '000'

iv_add_to_response_header = abap_true. "add the message to the header

3.改进

上面的写法是把错误内容写到HEADER里，但读取时总是有些麻烦，而在WEBIDE中，默认程序模板并不能调用到上面返回的错误信息，使用如下的代码，在SAP WEB IDE中可以默认返回错误内容，但内容信息有点长，也是还需要再进行改进。

    DATA: lo_message_container TYPE REF TO /iwbep/if_message_container.
    DATA: l_msgtx    TYPE symsgv,
          l_msg_text TYPE bapi_msg,
          LS_MESSAGE TYPE SCX_T100KEY.


      LS_MESSAGE-MSGID = ''.
      LS_MESSAGE-MSGNO = ''.
      LS_MESSAGE-ATTR1 = '保存数据失败'.
      RAISE EXCEPTION TYPE /IWBEP/CX_MGW_BUSI_EXCEPTION
          EXPORTING
            TEXTID = LS_MESSAGE.

DATA: lo_message_container TYPE REF TO /iwbep/if_message_container.

DATA: l_msgtx TYPE symsgv,

l_msg_text TYPE bapi_msg,

LS_MESSAGE TYPE SCX_T100KEY.

LS_MESSAGE-MSGID = ''.

LS_MESSAGE-MSGNO = ''.

LS_MESSAGE-ATTR1 = '保存数据失败'.

RAISE EXCEPTION TYPE /IWBEP/CX_MGW_BUSI_EXCEPTION

EXPORTING

TEXTID = LS_MESSAGE.

更多相关函数可参看：

ADD_MESSAGE_FROM_EXCEPTION
ADD_MESSAGES_FROM_BAPI
ADD_MESSAGE_FROM_BAPI
ADD_MESSAGE
ADD_MESSAGE_TEXT_ONLY

此时我们测试时会得到如图

4.SAPUI5中使用此ODATA错误消息的用法

sap.ui.define([
  "sap/ui/core/mvc/Controller"
], function(Controller) {
  "use strict";

  return Controller.extend("com.saplearners.controller.View1", {
    onInit: function() {

      var oModel = new sap.ui.model.json.JSONModel();
      this.getView().setModel(oModel, "viewData");

      var oServiceModel = new sap.ui.model.odata.v2.ODataModel("/sap/opu/odata/sap/ZMSG_CONT_DEMO_SRV/");
      var mParameters = {
        method: "GET",
        success: jQuery.proxy(function(oData, response) {
          this.getView().getModel("viewData").setProperty("/AirlineSet", oData.results);

          // response header
          var hdrMessage = response.headers["sap-message"];
          var hdrMessageObject = JSON.parse(hdrMessage);

          // log the header message
          console.log(hdrMessageObject);
          console.log(hdrMessageObject.message);
        }, this),

        error: jQuery.proxy(function(oError) {

        }, this)
      };

      oServiceModel.read("/AirlineSet", mParameters);
    }

  });
});

sap.ui.define([

"sap/ui/core/mvc/Controller"

], function(Controller) {

"use strict";

return Controller.extend("com.saplearners.controller.View1", {

onInit: function() {

var oModel = new sap.ui.model.json.JSONModel();

this.getView().setModel(oModel, "viewData");

var oServiceModel = new sap.ui.model.odata.v2.ODataModel("/sap/opu/odata/sap/ZMSG_CONT_DEMO_SRV/");

var mParameters = {

method: "GET",

success: jQuery.proxy(function(oData, response) {

this.getView().getModel("viewData").setProperty("/AirlineSet", oData.results);

// response header

var hdrMessage = response.headers["sap-message"];

var hdrMessageObject = JSON.parse(hdrMessage);

// log the header message

console.log(hdrMessageObject);

console.log(hdrMessageObject.message);

}, this),

error: jQuery.proxy(function(oError) {

}, this)

};

oServiceModel.read("/AirlineSet", mParameters);

}

});