Datenübergabe JSON-Array an FreeSMS-Anbieter

[Sir Rufo]

Hier mal so eine Implementierung mit einem Interface

Delphi-Quellcode:

unit Service.SmsGateway;

interface

uses
  System.SysUtils;

type
  ESmsGatewayException = class( Exception );
  ESmsGatewayApiException = class( ESmsGatewayException );
  ESmsGatewayProtocolException = class( ESmsGatewayException );

  ISmsGateway = interface
    ['{824896A1-4A78-4470-993D-5C96881C612B}']
    procedure SendMessage( const APhoneNumber, AMessage : string ); overload;
    procedure SendMessage( const APhoneNumbers : array of string; const AMessage : string ); overload;
  end;

implementation

end.

Delphi-Quellcode:

unit com.freesmsgateway.api_send;

interface

uses
  Service.SmsGateway;

type
  TSmsGateway = class( TInterfacedObject, ISmsGateway )
  // Keine Magic Numbers/Values im Code
  // sondern als Konstanten definieren
  private const
    C_APIURL = 'http://www.freesmsgateway.com/api_send';
    C_ACCESSTOKEN = 'access_token';
    C_MESSAGE = 'message';
    C_MESSAGE_MAXLENGTH = 160;
    C_SENDTO = 'send_to';
    C_CONTACTS_EXISTING = 'existing_contacts';
    C_CONTACTS_POST = 'post_contacts';
    C_RESPONSE_OK = 'Message sent';
  private
    FAccessToken : string;
  public
    constructor Create( const AAccessToken : string );
    procedure SendMessage( const APhoneNumber, AMessage : string ); overload;
    procedure SendMessage( const APhoneNumbers : array of string; const AMessage : string ); overload;
  end;

implementation

uses
  System.Classes, System.SysUtils,
  Data.DBXJSON,
  IdException, IdHTTP;

function JSONStrArray( const AStrArray : array of string ) : string;
var
  LIdx : Integer;
  LResult : TJSONArray;
begin
  LResult := TJSONArray.Create;
  try
    for LIdx := Low( AStrArray ) to High( AStrArray ) do
    begin
      LResult.Add( AStrArray[LIdx] );
    end;
    Result := LResult.ToString;
  finally
    LResult.Free;
  end;
end;

{ TSmsGateway }

constructor TSmsGateway.Create( const AAccessToken : string );
begin
  inherited Create;

  { TODO :
    Validierung AAccessToken
    sonst EArgumentException werfen }

  if ( AAccessToken = '' )
  then
    raise EArgumentException.Create( 'AccessToken muss angegeben werden' );

  FAccessToken := AAccessToken;
end;

procedure TSmsGateway.SendMessage( const APhoneNumber, AMessage : string );
begin
  SendMessage( [APhoneNumber], AMessage );
end;

procedure TSmsGateway.SendMessage( const APhoneNumbers : array of string; const AMessage : string );
var
  LParams : TStringList;
  LHttp : TIdHttp;
  LResponse : string;
begin

  { TODO :
    Validierung APhoneNumbers:
    - gültige Telefon-Nummern
    sonst EArgumentException werfen }

  if Length( APhoneNumbers ) = 0
  then
    raise EArgumentOutOfRangeException.Create( 'Telefonnummer fehlt' );

  { TODO : alternativ in mehrere Nachrichten aufteilen }

  if Length( AMessage ) > C_MESSAGE_MAXLENGTH
  then
    raise EArgumentException.CreateFmt( 'Nachrioht darf max. %d Zeichen beinhalten', [C_MESSAGE_MAXLENGTH] );

  LParams := nil;
  LHttp := nil;
  try
    LParams := TStringList.Create;

    LParams.Values[C_ACCESSTOKEN] := FAccessToken;
    LParams.Values[C_MESSAGE] := AMessage;
    LParams.Values[C_SENDTO] := C_CONTACTS_POST;
    LParams.Values[C_CONTACTS_POST] := JSONStrArray( APhoneNumbers );

    LHttp := TIdHttp.Create( nil );

    try
      LResponse := LHttp.Post( C_APIURL, LParams );
    except
      on E : EIdException do
        raise ESmsGatewayProtocolException.CreateFmt( 'FreeSMSGateway.com: (%s) %s', [E.ClassName, E.Message] );
    end;

    if not LResponse.EndsWith( C_RESPONSE_OK )
    then
      raise ESmsGatewayApiException.CreateFmt( 'FreeSMSGateway.com: %s', [LResponse] );

  finally
    LHttp.Free;
    LParams.Free;
  end;
end;

end.