FR: Add simple message types validators for the WRP messages

[denopink]

Overview

related to #25, #78, xmidt-org/scytale#88, xmidt-org/talaria#153 and builds on top of #80 and #84 .

tl;dr

This pr introduces our wrp simple message types validators built with our validation framework introduced in #80 and leverages basic spec validators introduced in #84 . Clients can leverage these prebuilt validators to validate their messages.

Explanation

• Validates requirements described at https://xmidt.io/docs/wrp/simple-messages/
• Includes basic spec validation described at xmidt.io/docs/wrp/basics
• Validates all string fields are UTF8

Clients can leverage our prebuilt validators to validate their messages, such as SimpleEventValidators and SimpleResponseRequestValidators:

msgv, err := NewTypeValidator(
	// Validates found msg types
	map[MessageType]Validator{
		SimpleEventMessageType:           SimpleEventValidators(),
		SimpleRequestResponseMessageType: SimpleResponseRequestValidators(),
	},
	// Validates unfound msg types
	AlwaysInvalid())
if err != nil {
	return
}

var (
	expectedStatus                  int64 = 3471
	expectedRequestDeliveryResponse int64 = 34
	expectedIncludeSpans            bool  = true
)
foundErrFailure := msgv.Validate(Message{
	Type: SimpleRequestResponseMessageType,
	// Missing scheme
	Source: "external.com",
	// Invalid Mac
	Destination:             "MAC:+++BB-44-55",
	TransactionUUID:         "DEADBEEF",
	ContentType:             "ContentType",
	Accept:                  "Accept",
	Status:                  &expectedStatus,
	RequestDeliveryResponse: &expectedRequestDeliveryResponse,
	Headers:                 []string{"Header1", "Header2"},
	Metadata:                map[string]string{"name": "value"},
	Spans: [][]string{
		// // Invalid length
		{},
		// Invalid length
		{"3"},
		// Invalid 'start time', 'duration' and 'status' components
		{"parent", "name", "not start time", "not duration", "not status"},
		// Invalid 'parent' and 'name' components
		{"1234", "1234", "1234", "1234", "1234"},
	},
	IncludeSpans: &expectedIncludeSpans,
	Path:         "/some/where/over/the/rainbow",
	Payload:      []byte{1, 2, 3, 4, 0xff, 0xce},
	ServiceName:  "ServiceName",
	// Not UFT8 URL string
	URL:        "someURL\xed\xbf\xbf.com",
	PartnerIDs: []string{"foo"},
	SessionID:  "sessionID123",
}) // Found error
foundErrSuccess1 := msgv.Validate(Message{
	Type:        SimpleRequestResponseMessageType,
	Source:      "MAC:11:22:33:44:55:66",
	Destination: "MAC:11:22:33:44:55:61",
}) // Found success
foundErrSuccess2 := msgv.Validate(Message{
	Type:   SimpleEventMessageType,
	Source: "MAC:11:22:33:44:55:66",
	// Invalid Destination
	Destination: "invalid:a-BB-44-55",
}) // Found error
unfoundErrFailure := msgv.Validate(Message{Type: CreateMessageType}) // Unfound error
fmt.Println(foundErrFailure == nil, foundErrSuccess1 == nil, foundErrSuccess2 == nil, unfoundErrFailure == nil)
// Output: false true false false

Type of Change(s)

• Non-breaking Enhancement
• All new and existing tests passed.

[codecov]

Codecov Report

Merging #85 (f0c26e2) into main (1bdb169) will increase coverage by 0.80%.
The diff coverage is 47.53%.

@@            Coverage Diff             @@
##             main      #85      +/-   ##
==========================================
+ Coverage   50.16%   50.97%   +0.80%     
==========================================
  Files          21       24       +3     
  Lines        3827     3949     +122     
==========================================
+ Hits         1920     2013      +93     
- Misses       1736     1760      +24     
- Partials      171      176       +5     

Flag	Coverage Δ
unittests	50.97% <47.53%> (+0.80%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
messages.go	96.77% <ø> (ø)
messages_codec.go	34.48% <20.17%> (+0.03%)	⬆️
qoslevel_string.go	40.00% <40.00%> (ø)
qos.go	100.00% <100.00%> (ø)
simpleMessageTypes_validator.go	100.00% <100.00%> (ø)
spec_validator.go	100.00% <100.00%> (ø)
validator.go	100.00% <100.00%> (ø)

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[mtrinh11]

Super duper minor comments, otherwise lgtm!