Protecting the transaction

castle = ::Castle::Client.new

begin
  token = request.params['castle_request_token']
  context = Castle::Context::Prepare.call(request)

  res = castle.risk(
    type: '$transaction',
    status: '$succeeded',
    request_token: token,
    context: {
      ip: context[:ip],
      headers: context[:headers]
    },
    user: {
      id: 'ca1242f498', # Required. A unique, persistent user identifier
      email: 'mgray@example.com' # Recommended
      # See the registration or login guides for more attributes
    },
    transaction: {
      id: '32301', # Required. Your local, unique reference to the transaction
      type: '$purchase', # Required
      base_amount: '99.99', # Optional
      amount: { # Optional
        type: '$fiat', # Optional. Defaults to $fiat. Can also be $crypto
        value: '99.99', # Required
        currency: 'USD' # Required
      },
      payment_method: {
        type: "$card", # Required
        fingerprint: "Xt5EWLLDS7FJjR1c", # Unique cross-user ID
        holder_name: "John Smith",
        country_code: "US", # The origin of the card or bank account
        bank_name: "Capital One",
        card: {
          bin: "457173", # A string of 6 or 8 digits
          last4: "4242", # A string of 4 digits
          exp_month: 8,
          exp_year: 2022,
          network: "$visa",
          funding: "$credit",
        },
        billing_address: {
          line1: "150 Earl St",
          line2: "Suite 482",
          city: "San Francisco",
          postal_code: "94111",
          region_code: "CA",
          country_code: "US" # Required
        }
      },
      shipping_address: {
        line1: "150 Earl St",
        line2: "Suite 482",
        city: "San Francisco",
        postal_code: "94111",
        region_code: "CA",
        country_code: "US" # Required
      }
    }
  )

  if res[:policy][:action] == 'deny'
    # IMPLEMENT: Deny attempt
  end

rescue Castle::InvalidRequestTokenError
  # Deny attempt. Likely a bad actor bypassing fingerprinting
rescue Castle::Error => e
  # Allow attempt. Data missing or invalid, or a server or timeout error
end

// NOTE: See the Ruby example for a more comprehensive set of parameters

try {
  $token = $_POST['castle_request_token'];

  $res = Castle::risk([
    'type' => '$transaction',
    'status' => '$succeeded',
    'request_token' => $token,
    'context' => [
      'ip' => Castle_RequestContext::extractIp(),
      'headers' => Castle_RequestContext::extractHeaders()
    ],
    'user' => [
      'id' => $user->id,
      'email' => $user->email
    ]
  ]);

  if ($res->risk > 0.9) {
    // IMPLEMENT: Deny attempt
  }

} catch (Castle_InvalidRequestTokenError $e) {
  // Deny attempt. Likely a bad actor bypassing fingerprinting
} catch (Castle_Error $e) {
  // Allow attempt. Data missing or invalid, or a server or timeout error
}

# NOTE: See the Ruby example for a more comprehensive set of parameters

try:
    token = request.form['castle_request_token'] # Using Flask
    context = ContextPrepare.call(request)
    client = Client()

    res = client.risk({
        'type': '$transaction',
        'status': '$succeeded',
        'request_token': token,
        'context': {
          'ip': context['ip'],
          'headers': context['headers']
        },
        'user': {
            'id': user.id,
            'email': user.email
        }
    })

    if res['risk'] > 0.9:
        # IMPLEMENT: Deny attempt

except InvalidRequestTokenError:
    # Deny attempt. Likely a bad actor bypassing fingerprinting
except CastleError as e:
    # Allow attempt. Data missing or invalid, or a server or timeout error

// NOTE: See the Ruby example for a more comprehensive set of parameters

String token = request.getParameter("castle_request_token");

Castle castle = Castle.initialize();
CastleContextBuilder context = castle.contextBuilder().fromHttpServletRequest(request)

try {
  CastleResponse response = castle.client().risk(ImmutableMap.builder()
    .put("type", "$transaction")
    .put("status", "$succeeded")
    .put(Castle.KEY_CONTEXT, ImmutableMap.builder()
      .put(Castle.KEY_IP, context.getIp())
      .put(Castle.KEY_HEADERS, context.getHeaders())
      build()
    )
    .put(Castle.KEY_USER, ImmutableMap.builder()
      .put("id", user.getId())
      .put("email", user.getEmail())
      .build()
    )
    .put(Castle.KEY_REQUEST_TOKEN, token)
    .build()
  );
  
  float risk = response.json().getAsJsonObject().get("risk").getAsFloat();

  if (risk > 0.9) {
    // IMPLEMENT: Deny attempt
  };
  
} catch (CastleApiInvalidRequestTokenException requestTokenException) {
    // IMPLEMENT: Deny attempt. Likely a bad actor
} catch (CastleRuntimeException runtimeException) {
    // Data missing or invalid. Needs to be fixed
}

// NOTE: See the Ruby example for a more comprehensive set of parameters

try {
  const token = request.body["castle_request_token"]; // Using Express

  const castle = new Castle({ apiSecret: 'YOUR SECRET HERE' });
  const context = ContextPrepareService.call(request, {}, castle.configuration);

  const res = castle.risk({
    type: '$transaction',
    status: '$succeeded',
    request_token: token,
    user: {
      id: user.id,
      email: user.email
    },
    context: {
      ip: context.ip,
      headers: context.headers
    }
  });

  if (res.risk > 0.9) {
    // IMPLEMENT: Deny attempt
  }
} catch (e) {
  if (e instanceof InvalidRequestTokenError) {
     // IMPLEMENT: Deny attempt. Likely a bad actor
  } else if (e instanceof APIError) {
     // Allow attempt. Data missing or invalid, or a server or timeout error
  }
}