Delphi 2007 SOAP 错误处理

Question

我正在 Delphi 2007 中编写一个 SOAP 客户端来进行简单的海关放行检查。我向 SOAP 服务器发送了一些信息，如果服务器找不到我发送的信息，我应该收到有关海关放行的详细信息或 SOAP 故障。第一部分工作正常，但故障处理却不行。 WSDL 指定了一个自定义 SOAP 异常（这包含在主 WSDL 中 - 整个 WSDL 没有显示）：

<?xml version="1.0" encoding="ISO-8859-1"?>
<xsd:schema targetNamespace="http://trips.crownagents.com/wsexception/message"
            xmlns:xsd="http://www.w3.org/2001/XMLSchema"
            xmlns="http://trips.crownagents.com/wsexception/message">
  <xsd:element name="WSException" type="WSException" nillable="true"/>
  <xsd:complexType name="WSException">
    <xsd:sequence>
      <xsd:element name="ErrorCode" type="xsd:string" minOccurs="0" maxOccurs="1"/>
      <xsd:element name="ErrorDescription" type="xsd:string" minOccurs="0" maxOccurs="1"/>
      <xsd:element name="Stack" type="xsd:string" minOccurs="0" maxOccurs="1"/>
    </xsd:sequence>
  </xsd:complexType>
</xsd:schema>

我得到的 SOAP 响应似乎引用了异常：

<?xml version="1.0" encoding="UTF-8"?>
<env:Envelope xmlns:env="http://schemas.xmlsoap.org/soap/envelope/" 
              xmlns:xsd="http://www.w3.org/2001/XMLSchema" 
              xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
              xmlns:ns0="http://trips.crownagents.com/wsexception/message" 
              xmlns:ns1="http://trips.crownagents.com/external/customs/release/message" 
              xmlns:ns2="http://trips.crownagents.com/external/common/message">
  <env:Body>
    <env:Fault xsi:type="env:Fault">
      <faultcode>env:Server</faultcode>
      <faultstring xsi:nil="1"/>
      <detail>
        <ans1:WSExceptionResponse xmlns:ans1="http://msgsvr.trips.crownagents.com/">
          <ErrorCode>0002</ErrorCode>
          <ErrorDescription>Invalid Declaration</ErrorDescription>
          <Stack>getSingleResult() did not retrieve any entities.</Stack>
        </ans1:WSExceptionResponse>
      </detail>
    </env:Fault>
  </env:Body>
</env:Envelope>

但是，我的代码永远不会看到 WSExceptionResponse。相反，我得到了一个通用的 ERemotableException：

Try
  Res := Rel.releaseStatus(RelInfo);
Except
  On E: WSExceptionResponse Do  // This never fires
    Status('Release check error (' + E.ErrorCode + ' - ' +
           E.ErrorDescription + ').', True);
  Else
    Status('Release check error (' + Exception(ExceptObject).Message +
           ').', True);
End;

我已阅读到 Delphi 2007 (https://groups.google.com/forum/#!msg/borland.public.delphi.webservices.soap/71t3P-vPMbk/qw9JVTEVS3YJ) 中的 SOAP 处理存在一些问题，我已更改 OPToSOAPDomConv.pas 文件以根据建议恢复它，但这无济于事。有没有人知道我可能做错了什么？

Answer 1

对于遇到此问题的仍在使用 Delphi 2007 的其他人，这就是我解决此问题的方法。

首先，将 OPToSOAPDomConv.pas 和 InvokeRegistry.pas 从 Delphi 源目录 (\Program Files\CodeGear\RAD Studio\5.0\source\Win32\soap) 复制到您的项目目录。将这两个文件添加到您的项目中，因为您将自定义源代码，并且您需要将它们与您的项目一起重新编译，而不是使用 Delphi 附带的预编译 DCU。

在 OPToSOAPDomConv.pas 文件中，找到 ProcessFault 过程并将其替换为以下内容：

procedure TOPToSoapDomConvert.ProcessFault(FaultNode: IXMLNode);
var
  FA, FC, FD, FS, CustNode: IXMLNode;
  I, J: Integer;
  AMessage: WideString;
  AClass: TClass;
  URI, TypeName: WideString;
  Count: Integer;
  PropList: PPropList;
  Ex: ERemotableException;

  function GetNodeURIAndName(const Node: IXMLNode; var TypeURI,
    ElemName: InvString): boolean;
  var
    Pre: InvString;
  begin
    ElemName := Node.NodeName;
    if IsPrefixed(ElemName) then
    begin
      Pre := ExtractPrefix(ElemName);
      ElemName := ExtractLocalName(ElemName);
      TypeURI := Node.FindNamespaceURI(Pre);
    end
    else
      TypeURI := Node.NamespaceURI;
    Result := True;
  end;

begin
  FA := nil;
  FC := nil;
  FD := nil;
  FS := nil;
  Ex := nil;
  for I := 0 to FaultNode.ChildNodes.Count - 1 do
  begin
    if      SameText(ExtractLocalName(FaultNode.ChildNodes[I].NodeName), SSoapFaultCode) then
      FC := FaultNode.ChildNodes[I]
    else if SameText(ExtractLocalName(FaultNode.ChildNodes[I].NodeName), SSoapFaultString) then
      FS := FaultNode.ChildNodes[I]
    else if SameText(ExtractLocalName(FaultNode.ChildNodes[I].NodeName), SSoapFaultDetails) then
      FD := FaultNode.ChildNodes[I]
    else if SameText(ExtractLocalName(FaultNode.ChildNodes[I].NodeName), SSoapFaultActor) then
      FA := FaultNode.ChildNodes[I];
  end;

  { Retrieve message from FaultString node }
  if FS <> nil then
    AMessage := FS.Text;

  { If there's a <detail> node, try to map it to a registered type }
  if FD <> nil then
  begin
    { Some SOAP stacks, including Delphi6 and others (see
      http://softwaredev.earthweb.com/script/article/0,,12063_641361_2,00.html)
      use the approach of putting custom fault info right at the <detail> node:

      Listing 4 - Application Fault Details
      <SOAP-ENV:Fault>
        <faultcode>300</faultcode>
        <faultstring>Invalid Request</faultstring>
        <runcode>1</runcode>
        <detail xmlns:e="GetTemperatureErr-URI"
                xmlns:xsi="http://www.w3.org/1999/XMLSchema-instance"
                xsi:type="e:GetTemperatureFault">
            <number>5575910</number>
            <description>Sensor Failure</description>
            <file>GetTemperatureClass.cpp</file>
            <line>481</line>
        </detail>
      </SOAP-ENV:Fault>

      However, much more common is the approach where the type and namespace
      are on the childnode of the <detail> node. Apache, MS and the SOAP spec.
      seem to lean towards that approach:

      Example 10 from the SOAP 1.1 Spec:

      <SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/">
         <SOAP-ENV:Body>
             <SOAP-ENV:Fault>
                 <faultcode>SOAP-ENV:Server</faultcode>
                 <faultstring>Server Error</faultstring>
                 <detail>
                     <e:myfaultdetails xmlns:e="Some-URI">
                       <message>My application didn't work</message>
                       <errorcode>1001</errorcode>
                     </e:myfaultdetails>
                 </detail>
             </SOAP-ENV:Fault>
         </SOAP-ENV:Body>
      </SOAP-ENV:Envelope>

      For interop reasons we favor the later approach but we'll support both here!!
    }
    CustNode := nil;
    if GetElementType(FD, URI, TypeName) then
      CustNode := FD
    else
    begin
      if ntElementChildCount(FD) > 0 then
      begin
        CustNode := ntElementChild(FD, 0);
        if not GetElementType(CustNode, URI, TypeName) and
           not GetNodeURIAndName(CustNode, URI, TypeName) then
          CustNode := nil;
      end;
    end;

    if (CustNode <> nil) then
    begin
      AClass := RemClassRegistry.URIToClass(URI, TypeName);
      if AClass <> nil then
      begin
        if AClass.InheritsFrom(ERemotableException) then
        begin
          Ex := ERemotableExceptionClass(AClass).Create(AMessage);
          LoadObject(Ex, FaultNode, CustNode);
        end;
      end;
    end;
  end;

  { Create default SOAP invocation exception if no suitable class was found }
  if Ex = nil then
    Ex := ERemotableException.Create(AMessage);
  if FA <> nil then
    Ex.FaultActor := FA.Text;
  if FC <> nil then
    Ex.FaultCode := FC.Text;
  if FD <> nil then
    Ex.FaultDetail := FD.XML;
  raise Ex;
end;

接下来，找到 GetElementType 函数并将其替换为以下内容：

function TSOAPDomConv.GetElementType(Node: IXMLNode; var TypeURI, TypeName: InvString): Boolean;
var
  Idx: Integer;
  S : InvString;
  V: Variant;
  Pre: InvString;
begin
  TypeURI := '';
  TypeName := '';
  Result := False;
  if (Node.NamespaceURI = SSoap11EncodingS5) and
     (Node.LocalName = SSoapEncodingArray) then
  begin
    TypeURI := SSoap11EncodingS5;
    TypeName := SSoapEncodingArray;
    Result := True;
  end
  else
  begin
    V := GetTypeBySchemaNS(Node, XMLSchemaInstNameSpace);
    if VarIsNull(V) then
      V := Node.GetAttribute(SSoapType);
    if not VarIsNull(V) then
    begin
      S := V;
      Idx := Pos(':', S);  { do not localize }
      if Idx <> 0 then
      begin
        TypeName := Copy(S, Idx + 1, High(Integer));
        Pre := Copy(S, 1, Idx - 1);
        TypeURI := Node.FindNamespaceURI(Pre);
      end
      else
      begin
        TypeName := S;
        TypeURI := '';
      end;
      Result := True;
    end;
  end
end;

最后，打开 InvokeRegistry.pas 文件，找到 GetExternalPropName 函数。更改显示以下内容的行：

if Info.Kind = tkClass then

到这里：

if (Info.Kind = tkClass) and Assigned(GetTypeData(info).ParentInfo) then

编译并运行你的应用程序，你应该会很好。

所有功劳归于此线程http://www.codenewsfast.com/cnf/article/859054074/permalink.art-ng1920q2368 和此http://www.delphigroups.info/2/7/342954.html 中的用户。