ql/mcp-common

Common library for Quicken Loans PHP projects

2.0.0 2018-05-18 18:03 UTC

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MCP Common

This package provides common code, utilities, and data types used by most other MCP or Quicken Loans PHP packages.

Installation

composer require ql/mcp-common ~2.0

Table of Contents

GUID

This class represents a Microsoft .NET GUID. Note that a Microsoft .NET GUID is the same as an RFC 4122 UUID, standard variant, 4th algorithm (see chapter 4.4 of RFC 4122 for details).

use QL\MCP\Common\GUID;

$guid = GUID::create();
echo $guid;

// {4577267B-AE54-4C03-8C86-E628D5D3695A}

All of the following create calls create calls result in the same GUID value.

use QL\MCP\Common\GUID;

$guid0 = GUID::createFromBin(base64_decode('T/l0arruT6OXO7O3QOOBKg=='));
$guid1 = GUID::createFromHex('4FF9746ABAEE4FA3973BB3B740E3812A');
$guid2 = GUID::createFromHex('4ff9746abaee4fa3973bb3b740e3812a');
$guid3 = GUID::createFromHex('4FF9746A-BAEE-4FA3-973B-B3B740E3812A');
$guid4 = GUID::createFromHex('4ff9746a-baee-4fa3-973b-b3b740e3812a');
$guid5 = GUID::createFromHex('{4FF9746ABAEE4FA3973BB3B740E3812A}');
$guid6 = GUID::createFromHex('{4ff9746abaee4fa3973bb3b740e3812a}');
$guid7 = GUID::createFromHex('{4FF9746A-BAEE-4FA3-973B-B3B740E3812A}');
$guid8 = GUID::createFromHex('{4ff9746a-baee-4fa3-973b-b3b740e3812a}');
$guid9 = GUID::createFromBase64('T/l0arruT6OXO7O3QOOBKg==');

//----------------

$guid = GUID::createFromHex('{0C875FFC-61AB-4A75-A4AF-5F89ADCE0D63}');

$guid->asHex();                  // '0C875FFC61AB4A75A4AF5F89ADCE0D63'
$guid->asBin();                  // pack('H*', '0C875FFC61AB4A75A4AF5F89ADCE0D63')
$guid->asBase64();               // 'DIdf/GGrSnWkr1+Jrc4NYw'
$guid->asHumanReadable();        // '{0C875FFC-61AB-4A75-A4AF-5F89ADCE0D63}'
$guid->format(GUID::HYPHENATED); // '{0c875ffc-61ab-4a75-a4af-5f89adce0d63}'

echo $guid;                      // '{0C875FFC-61AB-4A75-A4AF-5F89ADCE0D63}'

Clock

Any time an application wants to get the current time, it is recommended that this class is used to do that instead of using the native php date/time functions or classes such as time or date. The main reason for this is to facilitate unit testing. Since interacting with the system clock on a computer can be viewed as calling a service, this is something that should be wrapped and mocked when dealing with unit tests that rely on clock information.

If your app is diligent about injecting this object into others to get the current time rather than using native PHP, testing any time-sensitive application code becomes a trivial matter.

Note: These Time classes were created before the creation of DateTimeImmutable. DateTimeImmutable may replace some functionality of these classes in the future.

Usage:

use QL\MCP\Common\Clock;

$clock = new Clock;
$currentTime = $clock->read();

// TimePoint

If you want to see how a system operates at a specific point in time, the Clock may be set to something other than the system time or time zone. This is extremely useful for unit testing.

use QL\MCP\Common\Clock;

// Set a clock up to December 15, 1983 at 9:02pm located in Detroit, MI
$clock = new Clock('1983-12-15 21:02:00', 'America/Detroit');

One thing to note is that this clock will not change as the program continues to run. If you're looking for more accurate time measurements, this class would have to be change to work slightly differently than it is now. In other words, if your program is dealing with time resolution at or under a few seconds, this class is not sufficient for that.

The clock can also be used to parse datetimes from DateTime or strings.

use DateTime;
use QL\MCP\Common\Clock;

$clock = new Clock;

$time = $clock->fromDateTime(new DateTime);
var_dump($time);
// class QL\MCP\Common\Time\TimePoint#1 {}

$time = $clock->fromString('2015-12-10T10:30:00+04:00');
var_dump($time);
// class QL\MCP\Common\Time\TimePoint#2 {}

// Check the current time against an expiry, and optionally a created time and clock skew.

$clock = new Clock('2015-09-15 12:00:00', 'UTC');
$expiresAt = new TimePoint(2015, 9, 15, 10, 0, 0, 'America/Detroit');
$createdAt = new TimePoint(2015, 9, 15, 7, 0, 0, 'America/Detroit');
$skew = '30 seconds';

$isValid = $clock->inRange($expiresAt, $createdAt, $skew);
var_dump($isValid);

// bool(true)

TimePoint

This is a wrapper for the native php DateTime class. The changes made to the public API for this class are means to a very specific set of goals. These goals are as follows:

  1. Force the creation of a TimePoint to specify a time zone.
  2. Force the formatting of a string version of the TimePoint to require a viewing time zone.
  3. Force the parsing of a time string to happen outside of this class. Parsing and handling errors of parsed data are separate concerns and should be separate classes.
  4. This class is immutable in that any modification type functions create a new copy of the modified state.
use QL\MCP\Common\Time\TimeInterval;
use QL\MCP\Common\Time\TimePoint;

$time = new TimePoint(1999, 3, 31, 18, 15, 0, 'America/Detroit');

// returns a -1, 0 or 1 if $time is less than, equal to or greater than the argument respectively.
$time->compare(new TimePoint(1983, 12, 15, 21, 2, 0, 'America/Detroit'));
// -1

// the format string is exactly the same as DateTime->format(). Note the required timezone argument.
$time->format('Y-m-d H:i:s', 'UTC');
// '1999-03-31 23:15:00'

// Note that $time did not change, a copy was created. TimePoint->modify() takes the same argument format as modify()
$time2 = $time->modify('+1 day');
$time2->format('Y-m-d H:i:s', 'America/Detroit');
// '1999-04-01 18:15:00'

$time3 = $time->add(new TimeInterval('P2D'))
$time3->format('Y-m-d H:i:s', 'America/Detroit');
// '1999-04-02 18:15:00'

$time4 = $time->sub(new TimeInterval('P2D'))
$time4->format('Y-m-d H:i:s', 'America/Detroit');
// '1999-03-29 18:15:00'

$time5 = $time->diff(new TimePoint(1983, 12, 15, 21, 2, 0, 'America/Detroit'))
$time5->format('%y years, %m months, %d days, %h hours, %i minutes');
// '15 years, 3 months, 15 days, 21 hours, 13 minutes'

TimeInterval

This is a wrapper for the native PHP DateInterval class. It removes the public properties normally available on DateInterval (in favor of the format() function). The main purpose of this class is to represent a fixed range of time (ie 1 month, 3 days and 7 hours). It is usually used in conjunction with TimePoint and TimePeriod for calculations.

The format of time intervals conform to ISO 8601 Time Intervals. Also see DateInterval::__construct for more details on the interval spec.

use QL\MCP\Common\Time\TimeInterval;

// The interval spec is the exact same as PHP's DateInterval
$int = new TimeInterval('P1M3DT7H');

echo $interval->format("%d days %h hours\n");
// "3 days 7 hours"

TimePeriod

Wraps the native PHP DatePeriod class. This class represents a way to iterate over a set of date/times that occur at fixed intervals.

The native PHP class DatePeriod::__construct() is overloaded and is actually not possible to write in userland PHP. As a result, this wrapper exposes one of the creation options as a public static factory method.

use QL\MCP\Common\Time\TimeInterval;
use QL\MCP\Common\Time\TimePeriod;
use QL\MCP\Common\Time\TimePoint;

$start = new TimePoint(2012, 1, 1, 0, 0, 0, "America/Detroit");
$interval = new TimeInterval('P1W');

$end = new TimePoint(2012, 2, 1, 0, 0, 0, "America/Detroit");

$period0 = new TimePeriod($start, $interval, $end);
foreach ($period0 as $timePoint) {
    echo $timePoint->format("Y-m-d\n", "America/Detroit");
}

echo "\n";

$recurrences = 5;

$period1 = TimePeriod::createWithRecurrences($start, $interval, $recurrences);
foreach ($period1 as $timePoint) {
    echo $timePoint->format("Y-m-d\n", "America/Detroit");
}

/*
The output of the above code is as follows:

2012-01-01
2012-01-08
2012-01-15
2012-01-22
2012-01-29

2012-01-01
2012-01-08
2012-01-15
2012-01-22
2012-01-29
*/

Note that $period0 and $period1 are copies of the same time period, just constructed differently.

OpaqueProperty

Opaque Property is used to obscure secrets while in memory. This is useful to protect sensitive values from debug output such as stacktraces or mistaken echo or var_dump commands.

use QL\MCP\Common\OpaqueProperty;

$secret = new OpaqueProperty('my_secret_token');

echo $secret;
// [opaque property]

echo $secret->getValue();
// "my_secret_token"

ByteString

ByteString can be used to get byte offsets in binary strings, or total length in bytes. strlen and substr provide this functionality, but can be overridden in systems that use mbstring and mbstring.func_overload.

This utility protects against that scenario and always performs byte-based lengths and offsets, rather than character-based.

Please note: substr can be expensive when doing many offsets or string cuts and using array access is usually recommended if more performant code is required.

use QL\MCP\Common\Time\ByteString;

$string = 'abcd𐌀𐌁𐌂𐌃';
echo ByteString::strlen($string);
// int(20)

echo ByteString::substr($string, 6, 3);
// "𐌁"
// "f0908c81" in hex