TAbstractHttpConnectionClass = class of TAbstractHttpConnection;


const
  /// MIME content type used for JSON communication
  JSON_CONTENT_TYPE = 'application/json; charset=UTF-8';

  /// HTML Status Code for "Continue"
  HTTP_CONTINUE = 100;
  /// HTML Status Code for "Switching Protocols"
  HTTP_SWITCHINGPROTOCOLS = 101;
  /// HTML Status Code for "Success"
  HTTP_SUCCESS = 200;
  /// HTML Status Code for "Created"
  HTTP_CREATED = 201;
  /// HTML Status Code for "Accepted"
  HTTP_ACCEPTED = 202;
  /// HTML Status Code for "Non-Authoritative Information"
  HTTP_NONAUTHORIZEDINFO = 203;
  /// HTML Status Code for "No Content"
  HTTP_NOCONTENT = 204;


  /// HTML Status Code for "Multiple Choices"
  HTTP_MULTIPLECHOICES = 300;
  /// HTML Status Code for "Moved Permanently"
  HTTP_MOVEDPERMANENTLY = 301;
  /// HTML Status Code for "Found"
  HTTP_FOUND = 302;
  /// HTML Status Code for "See Other"
  HTTP_SEEOTHER = 303;
  /// HTML Status Code for "Not Modified"
  HTTP_NOTMODIFIED = 304;
  /// HTML Status Code for "Use Proxy"
  HTTP_USEPROXY = 305;
  /// HTML Status Code for "Temporary Redirect"
  HTTP_TEMPORARYREDIRECT = 307;
  /// HTML Status Code for "Bad Request"
  HTTP_BADREQUEST = 400;
  /// HTML Status Code for "Unauthorized"
  HTTP_UNAUTHORIZED = 401;
  /// HTML Status Code for "Forbidden"
  HTTP_FORBIDDEN = 403;
  /// HTML Status Code for "Not Found"
  HTTP_NOTFOUND = 404;
  // HTML Status Code for "Method Not Allowed"
  HTTP_NOTALLOWED = 405;
  // HTML Status Code for "Not Acceptable"
  HTTP_NOTACCEPTABLE = 406;
  // HTML Status Code for "Proxy Authentication Required"
  HTTP_PROXYAUTHREQUIRED = 407;
  /// HTML Status Code for "Request Time-out"
  HTTP_TIMEOUT = 408;
  /// HTML Status Code for "Internal Server Error"
  HTTP_SERVERERROR = 500;
  /// HTML Status Code for "Not Implemented"
  HTTP_NOTIMPLEMENTED = 501;
  /// HTML Status Code for "Bad Gateway"
  HTTP_BADGATEWAY = 502;
  /// HTML Status Code for "Service Unavailable"
  HTTP_UNAVAILABLE = 503;
  /// HTML Status Code for "Gateway Timeout"
  HTTP_GATEWAYTIMEOUT = 504;
  /// HTML Status Code for "HTTP Version Not Supported"
  HTTP_HTTPVERSIONNONSUPPORTED = 505;


/// gives access to the class type to implement a HTTP connection
// - will use WinHTTP API (from our SynCrtSock) under Windows
// - will use Indy for Delphi on other platforms
// - will use fcl-web (fphttpclient) with FreePascal

  TAbstractHttpConnectionClass = class of TAbstractHttpConnection;


const
  /// MIME content type used for JSON communication
  JSON_CONTENT_TYPE = 'application/json; charset=UTF-8';

  /// HTTP Status Code for "Continue"
  HTTP_CONTINUE = 100;
  /// HTTP Status Code for "Switching Protocols"
  HTTP_SWITCHINGPROTOCOLS = 101;
  /// HTTP Status Code for "Success"
  HTTP_SUCCESS = 200;
  /// HTTP Status Code for "Created"
  HTTP_CREATED = 201;
  /// HTTP Status Code for "Accepted"
  HTTP_ACCEPTED = 202;
  /// HTTP Status Code for "Non-Authoritative Information"
  HTTP_NONAUTHORIZEDINFO = 203;
  /// HTTP Status Code for "No Content"
  HTTP_NOCONTENT = 204;
  /// HTTP Status Code for "Partial Content"
  HTTP_PARTIALCONTENT = 206;
  /// HTTP Status Code for "Multiple Choices"
  HTTP_MULTIPLECHOICES = 300;
  /// HTTP Status Code for "Moved Permanently"
  HTTP_MOVEDPERMANENTLY = 301;
  /// HTTP Status Code for "Found"
  HTTP_FOUND = 302;
  /// HTTP Status Code for "See Other"
  HTTP_SEEOTHER = 303;
  /// HTTP Status Code for "Not Modified"
  HTTP_NOTMODIFIED = 304;
  /// HTTP Status Code for "Use Proxy"
  HTTP_USEPROXY = 305;
  /// HTTP Status Code for "Temporary Redirect"
  HTTP_TEMPORARYREDIRECT = 307;
  /// HTTP Status Code for "Bad Request"
  HTTP_BADREQUEST = 400;
  /// HTTP Status Code for "Unauthorized"
  HTTP_UNAUTHORIZED = 401;
  /// HTTP Status Code for "Forbidden"
  HTTP_FORBIDDEN = 403;
  /// HTTP Status Code for "Not Found"
  HTTP_NOTFOUND = 404;
  // HTTP Status Code for "Method Not Allowed"
  HTTP_NOTALLOWED = 405;
  // HTTP Status Code for "Not Acceptable"
  HTTP_NOTACCEPTABLE = 406;
  // HTTP Status Code for "Proxy Authentication Required"
  HTTP_PROXYAUTHREQUIRED = 407;
  /// HTTP Status Code for "Request Time-out"
  HTTP_TIMEOUT = 408;
  /// HTTP Status Code for "Internal Server Error"
  HTTP_SERVERERROR = 500;
  /// HTTP Status Code for "Not Implemented"
  HTTP_NOTIMPLEMENTED = 501;
  /// HTTP Status Code for "Bad Gateway"
  HTTP_BADGATEWAY = 502;
  /// HTTP Status Code for "Service Unavailable"
  HTTP_UNAVAILABLE = 503;
  /// HTTP Status Code for "Gateway Timeout"
  HTTP_GATEWAYTIMEOUT = 504;
  /// HTTP Status Code for "HTTP Version Not Supported"
  HTTP_HTTPVERSIONNONSUPPORTED = 505;


/// gives access to the class type to implement a HTTP connection
// - will use WinHTTP API (from our SynCrtSock) under Windows
// - will use Indy for Delphi on other platforms
// - will use fcl-web (fphttpclient) with FreePascal

    function LoadFromFile(const jsonfile: TFileName): boolean;
  published
    /// returns all certificates information as a base-64 encoded text array
    property PublicBase64: variant read GetPublicBase64;
  end;

const
  /// HTML Status Code for "Continue"
  HTTP_CONTINUE = 100;
  /// HTML Status Code for "Switching Protocols"
  HTTP_SWITCHINGPROTOCOLS = 101;
  /// HTML Status Code for "Success"
  HTTP_SUCCESS = 200;
  /// HTML Status Code for "Created"
  HTTP_CREATED = 201;
  /// HTML Status Code for "Accepted"
  HTTP_ACCEPTED = 202;
  /// HTML Status Code for "Non-Authoritative Information"
  HTTP_NONAUTHORIZEDINFO = 203;
  /// HTML Status Code for "No Content"
  HTTP_NOCONTENT = 204;


  /// HTML Status Code for "Multiple Choices"
  HTTP_MULTIPLECHOICES = 300;
  /// HTML Status Code for "Moved Permanently"
  HTTP_MOVEDPERMANENTLY = 301;
  /// HTML Status Code for "Found"
  HTTP_FOUND = 302;
  /// HTML Status Code for "See Other"
  HTTP_SEEOTHER = 303;
  /// HTML Status Code for "Not Modified"
  HTTP_NOTMODIFIED = 304;
  /// HTML Status Code for "Use Proxy"
  HTTP_USEPROXY = 305;
  /// HTML Status Code for "Temporary Redirect"
  HTTP_TEMPORARYREDIRECT = 307;
  /// HTML Status Code for "Bad Request"
  HTTP_BADREQUEST = 400;
  /// HTML Status Code for "Unauthorized"
  HTTP_UNAUTHORIZED = 401;
  /// HTML Status Code for "Forbidden"
  HTTP_FORBIDDEN = 403;
  /// HTML Status Code for "Not Found"
  HTTP_NOTFOUND = 404;
  // HTML Status Code for "Method Not Allowed"
  HTTP_NOTALLOWED = 405;
  // HTML Status Code for "Not Acceptable"
  HTTP_NOTACCEPTABLE = 406;
  // HTML Status Code for "Proxy Authentication Required"
  HTTP_PROXYAUTHREQUIRED = 407;
  /// HTML Status Code for "Request Time-out"
  HTTP_TIMEOUT = 408;
  /// HTML Status Code for "Internal Server Error"
  HTTP_SERVERERROR = 500;
  /// HTML Status Code for "Not Implemented"
  HTTP_NOTIMPLEMENTED = 501;
  /// HTML Status Code for "Bad Gateway"
  HTTP_BADGATEWAY = 502;
  /// HTML Status Code for "Service Unavailable"
  HTTP_UNAVAILABLE = 503;
  /// HTML Status Code for "Gateway Timeout"
  HTTP_GATEWAYTIMEOUT = 504;
  /// HTML Status Code for "HTTP Version Not Supported"
  HTTP_HTTPVERSIONNONSUPPORTED = 505;

  /// you can use this cookie value to delete a cookie on the browser side
  COOKIE_EXPIRED = '; Expires=Sat, 01 Jan 2010 00:00:01 GMT';

  /// used e.g. by THttpApiServer.Request for http.sys to send a static file
  // - the OutCustomHeader should contain the proper 'Content-type: ....'
................................................................................
procedure StatusCodeToErrorMsg(Code: integer; var result: RawUTF8); overload;

/// convert any HTTP_* constant to an integer error code and its English text
// - see @http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html
function StatusCodeToErrorMsg(Code: integer): RawUTF8; overload;

/// returns true for SUCCESS (200), CREATED (201), NOCONTENT (204),
// NOTMODIFIED (304) or TEMPORARYREDIRECT (307) codes
function StatusCodeIsSuccess(Code: integer): boolean;
  {$ifdef HASINLINE}inline;{$endif}

type
  /// the available HTTP methods transmitted between client and server
  // - some custom verbs are available in addition to standard REST commands
  // - most of iana verbs are available
................................................................................
  // limitation of 53-bit for integers - only for AJAX (non Delphi) clients
  // - unauthenticated requests from browsers (i.e. not Delphi clients) may
  // be redirected to the TSQLRestServer.Auth() method via rsoRedirectForbiddenToAuth
  // (e.g. for TSQLRestServerAuthenticationHttpBasic popup)
  // - some REST/AJAX clients may expect to return status code 204 as
  // instead of 200 in case of a successful operation, but with no returned
  // body (e.g. a DELETE with SAPUI5 / OpenUI5 framework): include
  // rsoHtml200WithNoBodyReturns204 so that any HTTP_SUCCESS (200) with no
  // returned body would return a HTTP_NOCONTENT (204)

  // - by default, Add() or Update() would return HTTP_CREATED (201) or
  // HTTP_SUCCESS (200) with no body, unless rsoAddUpdateReturnsContent is set
  // to return as JSON the last inserted/updated record
  // - TModTime / TCreateTime fields are expected to be filled on client side,
  // unless you set rsoComputeFieldsBeforeWriteOnServerSide so that AJAX requests
  // would set the fields on the server side by calling the TSQLRecord
  // ComputeFieldsBeforeWrite virtual method, before writing to the database
  TSQLRestServerOption = (
    rsoNoAJAXJSON,
    rsoGetAsJsonNotAsString,
    rsoGetID_str,
    rsoRedirectForbiddenToAuth,
    rsoHtml200WithNoBodyReturns204,
    rsoAddUpdateReturnsContent,
    rsoComputeFieldsBeforeWriteOnServerSide);
  /// allow to customize the TSQLRestServer process via its Options property
  TSQLRestServerOptions = set of TSQLRestServerOption;

  /// a generic REpresentational State Transfer (REST) server
  // - descendent must implement the protected EngineList() Retrieve() Add()
................................................................................
    HTTP_CONTINUE:            result := 'Continue';
    HTTP_SWITCHINGPROTOCOLS:  result := 'Switching Protocols';
    HTTP_SUCCESS:             result := 'OK';
    HTTP_CREATED:             result := 'Created';
    HTTP_ACCEPTED:            result := 'Accepted';
    HTTP_NONAUTHORIZEDINFO:   result := 'Non-Authoritative Information';
    HTTP_NOCONTENT:           result := 'No Content';

    HTTP_MULTIPLECHOICES:     result := 'Multiple Choices';
    HTTP_MOVEDPERMANENTLY:    result := 'Moved Permanently';
    HTTP_FOUND:               result := 'Found';
    HTTP_SEEOTHER:            result := 'See Other';
    HTTP_NOTMODIFIED:         result := 'Not Modified';
    HTTP_USEPROXY:            result := 'Use Proxy';
    HTTP_TEMPORARYREDIRECT:   result := 'Temporary Redirect';
................................................................................
  StatusCodeToErrorMsg(Code,result);
  result := FormatUTF8('HTTP Error % - %',[Code,result]);
end;

function StatusCodeIsSuccess(Code: integer): boolean;
begin
  case Code of
  HTTP_SUCCESS, HTTP_NOCONTENT, HTTP_CREATED,
  HTTP_NOTMODIFIED, HTTP_TEMPORARYREDIRECT:
    result := true;
  else
    result := false;
  end;
end;

................................................................................
      outcomingfile := false;
      if Call.OutBody<>'' then begin
        len := length(Call.OutHead);
        outcomingfile := (len>=25) and (Call.OutHead[15]='!') and
          IdemPChar(pointer(Call.OutHead),STATICFILE_CONTENT_TYPE_HEADER_UPPPER);
      end else // Call.OutBody=''
        if (Call.OutStatus=HTTP_SUCCESS) and
           (rsoHtml200WithNoBodyReturns204 in fOptions) then
          Call.OutStatus := HTTP_NOCONTENT;
      fStats.ProcessSuccess(outcomingfile);
    end else begin
      fStats.ProcessErrorNumber(Call.OutStatus);
      if Call.OutBody='' then // if no custom error message, compute it now as JSON
        Ctxt.Error(Ctxt.CustomErrorMsg,Call.OutStatus);
    end;

    function LoadFromFile(const jsonfile: TFileName): boolean;
  published
    /// returns all certificates information as a base-64 encoded text array
    property PublicBase64: variant read GetPublicBase64;
  end;

const
  /// HTTP Status Code for "Continue"
  HTTP_CONTINUE = 100;
  /// HTTP Status Code for "Switching Protocols"
  HTTP_SWITCHINGPROTOCOLS = 101;
  /// HTTP Status Code for "Success"
  HTTP_SUCCESS = 200;
  /// HTTP Status Code for "Created"
  HTTP_CREATED = 201;
  /// HTTP Status Code for "Accepted"
  HTTP_ACCEPTED = 202;
  /// HTTP Status Code for "Non-Authoritative Information"
  HTTP_NONAUTHORIZEDINFO = 203;
  /// HTTP Status Code for "No Content"
  HTTP_NOCONTENT = 204;
  /// HTTP Status Code for "Partial Content"
  HTTP_PARTIALCONTENT = 206;
    /// HTTP Status Code for "Multiple Choices"
  HTTP_MULTIPLECHOICES = 300;
  /// HTTP Status Code for "Moved Permanently"
  HTTP_MOVEDPERMANENTLY = 301;
  /// HTTP Status Code for "Found"
  HTTP_FOUND = 302;
  /// HTTP Status Code for "See Other"
  HTTP_SEEOTHER = 303;
  /// HTTP Status Code for "Not Modified"
  HTTP_NOTMODIFIED = 304;
  /// HTTP Status Code for "Use Proxy"
  HTTP_USEPROXY = 305;
  /// HTTP Status Code for "Temporary Redirect"
  HTTP_TEMPORARYREDIRECT = 307;
  /// HTTP Status Code for "Bad Request"
  HTTP_BADREQUEST = 400;
  /// HTTP Status Code for "Unauthorized"
  HTTP_UNAUTHORIZED = 401;
  /// HTTP Status Code for "Forbidden"
  HTTP_FORBIDDEN = 403;
  /// HTTP Status Code for "Not Found"
  HTTP_NOTFOUND = 404;
  // HTTP Status Code for "Method Not Allowed"
  HTTP_NOTALLOWED = 405;
  // HTTP Status Code for "Not Acceptable"
  HTTP_NOTACCEPTABLE = 406;
  // HTTP Status Code for "Proxy Authentication Required"
  HTTP_PROXYAUTHREQUIRED = 407;
  /// HTTP Status Code for "Request Time-out"
  HTTP_TIMEOUT = 408;
  /// HTTP Status Code for "Internal Server Error"
  HTTP_SERVERERROR = 500;
  /// HTTP Status Code for "Not Implemented"
  HTTP_NOTIMPLEMENTED = 501;
  /// HTTP Status Code for "Bad Gateway"
  HTTP_BADGATEWAY = 502;
  /// HTTP Status Code for "Service Unavailable"
  HTTP_UNAVAILABLE = 503;
  /// HTTP Status Code for "Gateway Timeout"
  HTTP_GATEWAYTIMEOUT = 504;
  /// HTTP Status Code for "HTTP Version Not Supported"
  HTTP_HTTPVERSIONNONSUPPORTED = 505;

  /// you can use this cookie value to delete a cookie on the browser side
  COOKIE_EXPIRED = '; Expires=Sat, 01 Jan 2010 00:00:01 GMT';

  /// used e.g. by THttpApiServer.Request for http.sys to send a static file
  // - the OutCustomHeader should contain the proper 'Content-type: ....'
................................................................................
procedure StatusCodeToErrorMsg(Code: integer; var result: RawUTF8); overload;

/// convert any HTTP_* constant to an integer error code and its English text
// - see @http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html
function StatusCodeToErrorMsg(Code: integer): RawUTF8; overload;

/// returns true for SUCCESS (200), CREATED (201), NOCONTENT (204),
// PARTIALCONTENT (206), NOTMODIFIED (304) or TEMPORARYREDIRECT (307) codes
function StatusCodeIsSuccess(Code: integer): boolean;
  {$ifdef HASINLINE}inline;{$endif}

type
  /// the available HTTP methods transmitted between client and server
  // - some custom verbs are available in addition to standard REST commands
  // - most of iana verbs are available
................................................................................
  // limitation of 53-bit for integers - only for AJAX (non Delphi) clients
  // - unauthenticated requests from browsers (i.e. not Delphi clients) may
  // be redirected to the TSQLRestServer.Auth() method via rsoRedirectForbiddenToAuth
  // (e.g. for TSQLRestServerAuthenticationHttpBasic popup)
  // - some REST/AJAX clients may expect to return status code 204 as
  // instead of 200 in case of a successful operation, but with no returned
  // body (e.g. a DELETE with SAPUI5 / OpenUI5 framework): include
  // rsoHttp200WithNoBodyReturns204 so that any HTTP_SUCCESS (200) with no
  // returned body would return a HTTP_NOCONTENT (204), as expected by
  // some clients
  // - by default, Add() or Update() would return HTTP_CREATED (201) or
  // HTTP_SUCCESS (200) with no body, unless rsoAddUpdateReturnsContent is set
  // to return as JSON the last inserted/updated record
  // - TModTime / TCreateTime fields are expected to be filled on client side,
  // unless you set rsoComputeFieldsBeforeWriteOnServerSide so that AJAX requests
  // would set the fields on the server side by calling the TSQLRecord
  // ComputeFieldsBeforeWrite virtual method, before writing to the database
  TSQLRestServerOption = (
    rsoNoAJAXJSON,
    rsoGetAsJsonNotAsString,
    rsoGetID_str,
    rsoRedirectForbiddenToAuth,
    rsoHttp200WithNoBodyReturns204,
    rsoAddUpdateReturnsContent,
    rsoComputeFieldsBeforeWriteOnServerSide);
  /// allow to customize the TSQLRestServer process via its Options property
  TSQLRestServerOptions = set of TSQLRestServerOption;

  /// a generic REpresentational State Transfer (REST) server
  // - descendent must implement the protected EngineList() Retrieve() Add()
................................................................................
    HTTP_CONTINUE:            result := 'Continue';
    HTTP_SWITCHINGPROTOCOLS:  result := 'Switching Protocols';
    HTTP_SUCCESS:             result := 'OK';
    HTTP_CREATED:             result := 'Created';
    HTTP_ACCEPTED:            result := 'Accepted';
    HTTP_NONAUTHORIZEDINFO:   result := 'Non-Authoritative Information';
    HTTP_NOCONTENT:           result := 'No Content';
    HTTP_PARTIALCONTENT:      result := 'Partial Content';
    HTTP_MULTIPLECHOICES:     result := 'Multiple Choices';
    HTTP_MOVEDPERMANENTLY:    result := 'Moved Permanently';
    HTTP_FOUND:               result := 'Found';
    HTTP_SEEOTHER:            result := 'See Other';
    HTTP_NOTMODIFIED:         result := 'Not Modified';
    HTTP_USEPROXY:            result := 'Use Proxy';
    HTTP_TEMPORARYREDIRECT:   result := 'Temporary Redirect';
................................................................................
  StatusCodeToErrorMsg(Code,result);
  result := FormatUTF8('HTTP Error % - %',[Code,result]);
end;

function StatusCodeIsSuccess(Code: integer): boolean;
begin
  case Code of
  HTTP_SUCCESS, HTTP_NOCONTENT, HTTP_PARTIALCONTENT, HTTP_CREATED,
  HTTP_NOTMODIFIED, HTTP_TEMPORARYREDIRECT:
    result := true;
  else
    result := false;
  end;
end;

................................................................................
      outcomingfile := false;
      if Call.OutBody<>'' then begin
        len := length(Call.OutHead);
        outcomingfile := (len>=25) and (Call.OutHead[15]='!') and
          IdemPChar(pointer(Call.OutHead),STATICFILE_CONTENT_TYPE_HEADER_UPPPER);
      end else // Call.OutBody=''
        if (Call.OutStatus=HTTP_SUCCESS) and
           (rsoHttp200WithNoBodyReturns204 in fOptions) then
          Call.OutStatus := HTTP_NOCONTENT;
      fStats.ProcessSuccess(outcomingfile);
    end else begin
      fStats.ProcessErrorNumber(Call.OutStatus);
      if Call.OutBody='' then // if no custom error message, compute it now as JSON
        Ctxt.Error(Ctxt.CustomErrorMsg,Call.OutStatus);
    end;

  // so that TServiceMethod.InternalExecute() would handle it directly
  TMVCAction = record
    /// the method name to be executed
    RedirectToMethodName: RawUTF8;
    /// may contain a JSON object which will be used to specify parameters
    // to the specified method
    RedirectToMethodParameters: RawUTF8;
    /// which HTML status code should be returned
    // - if RedirectMethodName is set, will return 307 HTTP_TEMPORARYREDIRECT
    // by default, but you can set here the expected HTML status code, e.g.
    // 201 HTTP_CREATED or 404 HTTP_NOTFOUND
    ReturnedStatus: cardinal;
  end;

  TMVCApplication = class;

  /// abtract MVC rendering execution context

  // so that TServiceMethod.InternalExecute() would handle it directly
  TMVCAction = record
    /// the method name to be executed
    RedirectToMethodName: RawUTF8;
    /// may contain a JSON object which will be used to specify parameters
    // to the specified method
    RedirectToMethodParameters: RawUTF8;
    /// which HTTP Status code should be returned
    // - if RedirectMethodName is set, will return 307 HTTP_TEMPORARYREDIRECT
    // by default, but you can set here the expected HTTP Status code, e.g.
    // 201 HTTP_CREATED or 404 HTTP_NOTFOUND
    ReturnedStatus: cardinal;
  end;

  TMVCApplication = class;

  /// abtract MVC rendering execution context

    /// finalize the context
    // - will release the TWebSocketProtocol associated instance
    destructor Destroy; override;
    /// will push a request or notification to the other end of the connection
    // - caller should set the aRequest with the outgoing parameters, and
    // optionally receive a response from the other end
    // - the request may be sent in blocking or non blocking mode
    // - returns the HTML status code (HTTP_SUCCESS=200 for success)
    function NotifyCallback(aRequest: THttpServerRequest;
      aMode: TWebSocketProcessNotifyCallback): cardinal; virtual;
    /// the settings currently used during the WebSockets process
    // - defined as a pointer so that you may be able to change the values
    function Settings: PWebSocketProcessSettings; {$ifdef HASINLINE}inline;{$endif}
    /// the associated communication socket
    // - on the server side, is a THttpServerSocket

    /// finalize the context
    // - will release the TWebSocketProtocol associated instance
    destructor Destroy; override;
    /// will push a request or notification to the other end of the connection
    // - caller should set the aRequest with the outgoing parameters, and
    // optionally receive a response from the other end
    // - the request may be sent in blocking or non blocking mode
    // - returns the HTTP Status code (e.g. HTTP_SUCCESS=200 for success)
    function NotifyCallback(aRequest: THttpServerRequest;
      aMode: TWebSocketProcessNotifyCallback): cardinal; virtual;
    /// the settings currently used during the WebSockets process
    // - defined as a pointer so that you may be able to change the values
    function Settings: PWebSocketProcessSettings; {$ifdef HASINLINE}inline;{$endif}
    /// the associated communication socket
    // - on the server side, is a THttpServerSocket

/// convert a supplied subject text into an Unicode encoding
// - will convert the text into UTF-8 and append '=?UTF-8?B?'
// - for pre-Unicode versions of Delphi, Text is expected to be already UTF-8
// encoded - since Delphi 2010, it will be converted from UnicodeString
function SendEmailSubject(const Text: string): SockString;

const
  /// HTML Status Code for "Success"
  STATUS_SUCCESS = 200;
  /// HTML Status Code for "Created"
  STATUS_CREATED = 201;
  /// HTML Status Code for "No Content"
  STATUS_NOCONTENT = 204;
  /// HTML Status Code for "Bad Request"
  STATUS_BADREQUEST = 400;
  /// HTML Status Code for "Unauthorized"
  STATUS_UNAUTHORIZED = 401;
  /// HTML Status Code for "Forbidden"
  STATUS_FORBIDDEN = 403;
  /// HTML Status Code for "Not Found"
  STATUS_NOTFOUND = 404;
  /// HTML Status Code for "Internal Server Error"
  STATUS_SERVERERROR = 500;
  /// HTML Status Code for "Not Implemented"
  STATUS_NOTIMPLEMENTED = 501;

  {$ifdef MSWINDOWS}
  /// can be used with THttpApiServer.AuthenticationSchemes to enable all schemes
  HTTPAPI_AUTH_ENABLE_ALL = [hraBasic..hraKerberos];
  {$endif}

/// convert a supplied subject text into an Unicode encoding
// - will convert the text into UTF-8 and append '=?UTF-8?B?'
// - for pre-Unicode versions of Delphi, Text is expected to be already UTF-8
// encoded - since Delphi 2010, it will be converted from UnicodeString
function SendEmailSubject(const Text: string): SockString;

const
  /// HTTP Status Code for "Success"
  STATUS_SUCCESS = 200;
  /// HTTP Status Code for "Created"
  STATUS_CREATED = 201;
  /// HTTP Status Code for "No Content"
  STATUS_NOCONTENT = 204;
  /// HTTP Status Code for "Bad Request"
  STATUS_BADREQUEST = 400;
  /// HTTP Status Code for "Unauthorized"
  STATUS_UNAUTHORIZED = 401;
  /// HTTP Status Code for "Forbidden"
  STATUS_FORBIDDEN = 403;
  /// HTTP Status Code for "Not Found"
  STATUS_NOTFOUND = 404;
  /// HTTP Status Code for "Internal Server Error"
  STATUS_SERVERERROR = 500;
  /// HTTP Status Code for "Not Implemented"
  STATUS_NOTIMPLEMENTED = 501;

  {$ifdef MSWINDOWS}
  /// can be used with THttpApiServer.AuthenticationSchemes to enable all schemes
  HTTPAPI_AUTH_ENABLE_ALL = [hraBasic..hraKerberos];
  {$endif}

'1.18.2890'

'1.18.2891'