Delphi调用WebService（通过SoapHeader认证）经验总结

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项目（Delphi开发）需要调用另一个系统的WebService。走了不少弯路，现记录总结一下经验。以下是WebService要求：

1、WebService概述

营销Webservice接口采用Apache Axis（version 1.4）技术实现。客户端和服务器用SOAP（Simple Object Access Protocol）协议通过HTTP来交互，客户端根据WSDL描述文档生成SOAP请求消息发送到服务端，服务端解析收到的SOAP请求，调用Web service，然后再生成相应的SOAP应答送回到客户端。

2 、认证机制

营销的所有Webservice服务均需要认证通过（部分需要授权）才能够被调用。营销Webservice服务接收到请求后从Soap头中获取用户名和密码，进行认证，认证通过后再调用具体服务。

作为客户端，应用程序代码(使用Axis的客户端编程模型来编写的)需要将用户名和密码设置到SOAPHeader中。SOAPHeaderElement的namespace约定为Authorization，localPart约定为username 和 password。

根据客户端程序语言及调用方式不同，设置的方法也不同，下面示例说明客户端程序语言为java调用方式为动态调用的设置方法：用org.apache.axis.client.Call 的addHeader方法：

call.addHeader(new SOAPHeaderElement("Authorization","username",username));

call.addHeader(new SOAPHeaderElement("Authorization","password",password));

其他的调用方式及其他语言设置方式请查阅Axis相关文档。

最终传输的SOAP报文格式如下：

最终传输的SOAP头信息如下：
<soapenv:Header>
        <ns1:username
    soapenv:actor="http://schemas.xmlsoap.org/soap/actor/next"
    soapenv:mustUnderstand="0" xsi:type="soapenc:string"
    xmlns:ns1="Authorization"        xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/">
            username
        </ns1:username>
        <ns2:password
    soapenv:actor="http://schemas.xmlsoap.org/soap/actor/next"
    soapenv:mustUnderstand="0" xsi:type="soapenc:string"
    xmlns:ns2="Authorization"        xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/">
            password
        </ns2:password>
    </soapenv:Header>

开始的时候，按照一般调用WebService方法进行：导入wsdl，自动生成WebService调用函数，手工添加一个类继承TSOAPHeader类，使用HTTPRIO发送SOAP报文。但是使用SOAPUI测试发出的报文，发现SoapHeader信息和WebService要求的格式不一样。

于是想到，在soap报文发出前，手动将soap报文改成WebService要求的格式，即在HTTPRIO的BeforeExecute事件中修改soap报文：

procedure TForm1.HTTPRIO1BeforeExecute(const MethodName: String;
  var SOAPRequest: WideString);
var
  head_begin,head_end,head_len: Integer;
  SOAPData: WideString;
  old_head: WideString;
begin
  SOAPData := SOAPRequest;
  //替换SOAP头
  head_begin := Pos('<SOAP-ENV:Header',SOAPData);
  head_end := Pos('</SOAP-ENV:Header>',SOAPData);
  head_len := head_end + Length('</SOAP-ENV:Header>') - head_begin;
  old_head := Copy(SOAPData,head_begin,head_len);
  SOAPData := StringReplace(SOAPData,old_head,NewSoapHeader,[rfReplaceAll, rfIgnoreCase]);
  //转义字符处理 &lt; 改 <
  SOAPData := StringReplace(SOAPData,'&lt;','<',[rfReplaceAll, rfIgnoreCase]);
  //转义字符处理 &gt; 改 >
  SOAPData := StringReplace(SOAPData,'&gt;','>',[rfReplaceAll, rfIgnoreCase]);

  SOAPRequest := SOAPData;

  Memo2.Clear;
  Memo2.Lines.Add(Utf8ToAnsi(SOAPRequest));
end;

但是，用SoapUI测试，发现这样修改后发出的报文Header没有了，只有Body部分。

仔细研究了一下Delphi的Soap相关控件，最终找到以下解决方法使用THTTPReqResp控件直接发送完整的soap报文，相关代码如下：

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs,IniFiles, DB, ADODB, StdCtrls, InvokeRegistry, Rio,
  SOAPHTTPClient,GenericServer1, ExtCtrls,ActiveX, SOAPHTTPTrans;

const  
  SOAP_DATA =
  '<?xml version="1.0"?>' +
  '<SOAP-ENV:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" ' +
  '  xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/"   xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/">' +
  '<SOAP-ENV:Header>' +
  '<ns1:username SOAP-ENV:actor="http://schemas.xmlsoap.org/soap/actor/next"  SOAP-ENV:mustUnderstand="0" xsi:type="soapenc:string"  xmlns:ns1="Authorization" ' +
  'xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/">' +
  ':WS_USER_NAME' +
  '</ns1:username>' +
  '<ns2:password  SOAP-ENV:actor="http://schemas.xmlsoap.org/soap/actor/next"  SOAP-ENV:mustUnderstand="0" xsi:type="soapenc:string"  xmlns:ns2="Authorization"  ' +
  'xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/">' +
  ':WS_PASSWORD' +
  '</ns2:password>' +
  '</SOAP-ENV:Header>' +
  '<SOAP-ENV:Body SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/">' +
  '<NS2:invoke xmlns:NS2="http://server.webservice.core.epm">' +
  '<path xsi:type="xsd:string">:WS_PATH</path>' +
  '<methodName xsi:type="xsd:string">:WS_METHOD_NAME</methodName>' +
  '<dataXmlStr xsi:type="xsd:string">' +
  '<![CDATA[' +
  ':WS_XML_DATA' +
  ']]>' +
  '</dataXmlStr>' +
  '</NS2:invoke>' +
  '</SOAP-ENV:Body>' +
  '</SOAP-ENV:Envelope>';
  
type
  TForm1 = class(TForm)
    ADOConnection1: TADOConnection;
    GroupBox8: TGroupBox;
    Label21: TLabel;
    Label22: TLabel;
    Label23: TLabel;
    Label24: TLabel;
    Label25: TLabel;
    edt_wsdl_url: TEdit;
    edt_path: TEdit;
    edt_method: TEdit;
    edt_user: TEdit;
    edt_password: TEdit;
    Button1: TButton;

    Memo1: TMemo;
    Label1: TLabel;
    Label2: TLabel;
    Memo2: TMemo;
    Timer_Ping: TTimer;
    HTTPReqResp1: THTTPReqResp;
    procedure FormCreate(Sender: TObject);procedure Button1Click(Sender: TObject); 
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
    procedure Timer_PingTimer(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
    NETWORK_ID, NETWORK_NAME, WSDL_URL, USER_NAME, PASSWORD, METHOD_NAME, PATH: WideString;
    dataXmlStr: WideString;
    NewSoapData: WideString;
procedure sendData();
  end;

  { 使用线程发送WebService }
  TPingThread = class(TThread)
  protected
     procedure execute; override;
  end;
  procedure write_log(str: string);//写入记录文件
var
  Form1: TForm1;
  { 初始化临界区CS变量 }
  PingCS:TRTLCriticalSection;
implementation
uses util_utf8;

{$R *.dfm}
procedure write_log(str: string);
var
  F: TextFile;
  mfile: string;
begin
  try
    //判断保存日志文件的目录是否存在
    if not DirectoryExists(ExtractFilePath(ParamStr(0)) + 'log') then
      MkDir(ExtractFilePath(ParamStr(0)) + 'log');

    //按日期及时间设定保存日志的文件名
    mfile := ExtractFilePath(ParamStr(0)) + 'log\' + formatdatetime('yyyy-mm-dd', now) + '.txt';

    AssignFile(F,mfile);
    if not FileExists(mfile) then
      Rewrite(F);//如果文件不存在，则创建一个新的文件，并写入
    Append(F); //追加写入
    Writeln(F,str);//写入并换行
    CloseFile(F);
  except
  end;
end;
//读txt
Procedure ReadTxt(FileName:String);
Var
  F:Textfile;
  str: String;
Begin
  AssignFile(F, FileName); {将文件名与变量 F 关联}
  Reset(F); {打开并读取文件 F }
  while not Eof(F) do
  begin
    Readln(F, str);
    Form1.Memo2.Lines.Add(str);
  end;  

  ShowMessage(str);
  Closefile(F); {关闭文件 F}
End;

procedure TForm1.FormCreate(Sender: TObject);
begin
  InitializeCriticalSection(PingCS);
end;

//发送
procedure TForm1.Button1Click(Sender: TObject);  
begin
  Timer_Ping.Enabled := True;
end;

procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
begin
  { 清除线程CS变量 } 
  DeleteCriticalSection(PingCS);
end;

procedure TForm1.Timer_PingTimer(Sender: TObject);
begin
  { 创建线程, 向LED屏发送数据 }
  TPingThread.Create(False);
end;
procedure TForm1.sendData;
var
  svc: GenericServer;
  tmpstr: string;
  strSend: TStringStream;
begin
  WSDL_URL := Trim(edt_wsdl_url.Text);
  USER_NAME := Trim(edt_user.Text);
  PASSWORD := Trim(edt_password.Text);
  METHOD_NAME := Trim(edt_method.Text);
  PATH := Trim(edt_path.Text);
  dataXmlStr := Trim(Memo1.Text);

  //获取自定义soap报文
  NewSoapData := SOAP_DATA;
  NewSoapData := StringReplace(NewSoapData,':WS_USER_NAME',USER_NAME,[rfReplaceAll, rfIgnoreCase]);
  NewSoapData := StringReplace(NewSoapData,':WS_PASSWORD',PASSWORD,[rfReplaceAll, rfIgnoreCase]);
  NewSoapData := StringReplace(NewSoapData,':WS_PATH',PATH,[rfReplaceAll, rfIgnoreCase]);
  NewSoapData := StringReplace(NewSoapData,':WS_METHOD_NAME',METHOD_NAME,[rfReplaceAll, rfIgnoreCase]);
  NewSoapData := StringReplace(NewSoapData,':WS_XML_DATA',dataXmlStr,[rfReplaceAll, rfIgnoreCase]);
  Memo2.Text := NewSoapData;
  //使用HTTPReqResp1控件进行发送soap报文，不适用HTTPRIO控件（发出的报文xml会被转义，也不需要导入wsdl了）
  CoInitialize(nil); //线程中使用必须加上CoInitialize(nil)和CoUninitilize()， 单元中要uses   activex。
  //将string转换成stream
  strSend := TStringStream.Create(NewSoapData);

  try
    try //加上try。。except，不要弹出爆粗提示
      HTTPReqResp1.URL := WSDL_URL;
      HTTPReqResp1.Send(strSend);
    except
      on e:Exception do
      begin
        write_log(FormatDateTime('yyyy-mm-dd hh:nn:ss',Now) + ' 调用WebService时发生异常，错误原因：'+E.Message); 
      end;
    end;
  finally
    strSend.Free;
    couninitialize;
  end
end;

{ TPingThread }

procedure TPingThread.execute;
begin
  Form1.Timer_Ping.Enabled :=false;
  FreeOnTerminate := True;
  {线程临界区代码块开始}
  EnterCriticalSection(PingCS);
  try
    form1.sendData;
  {线程临界区代码块结束}
  except
    on e:Exception do
    begin
      write_log(FormatDateTime('yyyy-mm-dd hh:nn:ss',Now) + ' TPingThread.execute：'+E.Message);
    end;
  end;
  LeaveCriticalSection(PingCS);
end;

end.