From 169b9499fe4def519aab5c84f4fd12f4d72fef0c Mon Sep 17 00:00:00 2001
From: "Stanislav N. aka pztrn" <pztrn@pztrn.name>
Date: Tue, 3 Dec 2019 21:21:57 +0500
Subject: [PATCH] Initial commit, valiwork as framework is ready to use.

---
 .drone.yml                        |  83 ++++++++++
 .golangci.yml                     |  17 ++
 README.md                         |  27 +++
 debug.go                          |  25 +++
 errors.go                         |  17 ++
 example/main.go                   |  43 +++++
 go.mod                            |   5 +
 go.sum                            |  12 ++
 validations.go                    |  97 +++++++++++
 validations_test.go               | 266 ++++++++++++++++++++++++++++++
 validators/validator_signature.go |   4 +
 11 files changed, 596 insertions(+)
 create mode 100644 .drone.yml
 create mode 100644 .golangci.yml
 create mode 100644 README.md
 create mode 100644 debug.go
 create mode 100644 errors.go
 create mode 100644 example/main.go
 create mode 100644 go.mod
 create mode 100644 go.sum
 create mode 100644 validations.go
 create mode 100644 validations_test.go
 create mode 100644 validators/validator_signature.go

diff --git a/.drone.yml b/.drone.yml
new file mode 100644
index 0000000..a94e1ce
--- /dev/null
+++ b/.drone.yml
@@ -0,0 +1,83 @@
+---
+kind: pipeline
+type: docker
+name: build
+
+steps:
+  - name: notify-start
+    image: pztrn/discordrone
+    settings:
+      webhook_id:
+        from_secret: discord_webhook_id
+      webhook_token:
+        from_secret: discord_webhook_secret
+      message: 'Starting testing, benchmarking and linting for **{{repo.name}}#{{build.number}}@{{commit.sha}}** @ {{datetime build.started "02-Jan-2006 15:04:05 MST" "Asia/Yekaterinburg"}} (See {{build.link}} for logs).'
+
+  - name: lint
+    image: golangci/golangci-lint:latest
+    environment:
+      CGO_ENABLED: 0
+    commands:
+      - golangci-lint run
+    depends_on:
+      - notify-start
+
+  - name: test
+    image: golang:1.13.4-alpine
+    environment:
+      CGO_ENABLED: 0
+    commands:
+      - go test -test.v ./...
+    depends_on:
+      - notify-start
+
+  - name: test-race
+    image: golang:1.13.4-alpine
+    environment:
+      CGO_ENABLED: 0
+    commands:
+      - go test -race -test.v ./...
+    depends_on:
+      - notify-start
+
+  - name: benchmark
+    image: golang:1.13.4-alpine
+    environment:
+      CGO_ENABLED: 0
+    commands:
+      - go test -benchmem -run=^$ go.dev.pztrn.name/valiwork -bench . 
+    depends_on:
+      - notify-start
+
+  - name: benchmark-race
+    image: golang:1.13.4-alpine
+    environment:
+      CGO_ENABLED: 0
+    commands:
+      - go test -benchmem -run=^$ go.dev.pztrn.name/valiwork -race -bench . 
+    depends_on:
+      - notify-start
+
+  - name: notify-end
+    when:
+      status:
+      - success
+      - failure
+    image: pztrn/discordrone
+    settings:
+      webhook_id:
+        from_secret: discord_webhook_id
+      webhook_token:
+        from_secret: discord_webhook_secret
+      message: "
+        {{#success build.status}}
+          **{{repo.name}}#{{build.number}}@{{commit.sha}}** tested, benchmarked and linted successfully.
+        {{ else }}
+          **{{repo.name}}#{{build.number}}@{{commit.sha}}** failed. See {{build.link}}.
+        {{/success}}"
+    depends_on:
+      - benchmark
+      - benchmark-race
+      - lint
+      - test
+      - test-race
\ No newline at end of file
diff --git a/.golangci.yml b/.golangci.yml
new file mode 100644
index 0000000..1e0096a
--- /dev/null
+++ b/.golangci.yml
@@ -0,0 +1,17 @@
+run:
+  deadline: 5m
+linters:
+  enable-all: true
+  disable:
+    # Because globals might exist, but according to our codestyle they
+    # should be lowercased and considered as unexported.
+    - gochecknoglobals
+    # While it might be useful it'll create more problems that will solve.
+    - gocritic
+    # This linter goes crazy for nothing (almost).
+    - funlen
+linters-settings:
+  lll:
+    line-length: 420
+  gocyclo:
+    min-complexity: 40
\ No newline at end of file
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..67feb94
--- /dev/null
+++ b/README.md
@@ -0,0 +1,27 @@
+# ValiWork - validation framework
+
+ValiWork is a validation framework that provides sane API and ability to write own validators that returns arbitrary things. It is goroutine-safe and fast.
+
+## Default validators
+
+There are no necessity to enable default validators at all. But if you want to - call:
+
+```go
+valiwork.InitializeDefaultValidators()
+```
+
+Default validators will return ``error``.
+
+## Validators registering and namespacing
+
+Default validators using "T_N" scheme, where ``T`` is data type (string, int, int64, etc.) and ``N`` is a validator name (which can be a generic string). Please, use same naming scheme. Example good validators names:
+
+* ``string_check_for_very_rare_symbol_that_is_not_allowed``
+* ``int64_check_if_in_bad_range``
+* ``interface_check_if_able_to_be_TheVeryGoodStruct``
+
+Key idea is to help you debugging this thing (see [debug section](#Debug) below).
+
+## Debug
+
+Define ``VALIWORK_DEBUG`` environment variable and set it to ``true`` to get debug output. Default ``log`` module will be used for that.
diff --git a/debug.go b/debug.go
new file mode 100644
index 0000000..44be4d9
--- /dev/null
+++ b/debug.go
@@ -0,0 +1,25 @@
+package valiwork
+
+import (
+	// stdlib
+	"os"
+	"strconv"
+)
+
+var (
+	DEBUG bool
+)
+
+// Initializes debug output.
+// nolint
+func init() {
+	debug, found := os.LookupEnv("VALIWORK_DEBUG")
+	if found {
+		debugBool, err := strconv.ParseBool(debug)
+		if err != nil {
+			return
+		}
+
+		DEBUG = debugBool
+	}
+}
diff --git a/errors.go b/errors.go
new file mode 100644
index 0000000..ef579da
--- /dev/null
+++ b/errors.go
@@ -0,0 +1,17 @@
+package valiwork
+
+import (
+	// stdlib
+	"errors"
+)
+
+var (
+	// ErrValidatorAlreadyRegistered appears when validator's name
+	// passed to RegisterValidator function already used for other
+	// validator function.
+	ErrValidatorAlreadyRegistered = errors.New("validator with such name already registered")
+
+	// ErrValidatorNotRegistered appears when trying to unregister
+	// not registered validator function.
+	ErrValidatorNotRegistered = errors.New("validator with such name wasn't registered")
+)
diff --git a/example/main.go b/example/main.go
new file mode 100644
index 0000000..393b1de
--- /dev/null
+++ b/example/main.go
@@ -0,0 +1,43 @@
+package main
+
+import (
+	"strings"
+	// stdlib
+	"errors"
+	"log"
+
+	// other
+	"go.dev.pztrn.name/valiwork"
+)
+
+const (
+	stringValidatorName = "string_validate_things"
+)
+
+func main() {
+	log.Println("Starting validation example...")
+	log.Println("WARN: to see additional valiwork output define 'VALIWORK_DEBUG' environment variable and set it to 'true'!")
+
+	//stringToValidate := " I am pretty b@d $tring"
+
+	valiwork.RegisterValidator(stringValidatorName, stringValidator)
+}
+
+func stringValidator(thing interface{}, optional ...interface{}) []interface{} {
+	var errs []interface{}
+
+	stringToValidate, ok := thing.(string)
+	if !ok {
+		errs = append(errs, errors.New("passed value is not a string"))
+		return errs
+	}
+
+	// Are string begins with spaces?
+	if strings.HasPrefix(stringToValidate, " ") {
+		errs = append(errs, errors.New("string begins with space"))
+	}
+
+	// Does string contains any special characters?
+
+	return errs
+}
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..9cf867b
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,5 @@
+module go.dev.pztrn.name/valiwork
+
+go 1.13
+
+require github.com/stretchr/testify v1.4.0
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..68164f9
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,12 @@
+github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/objx v0.1.0 h1:4G4v2dO3VZwixGIRoQ5Lfboy6nUhCyYzaqnIAPPhYs4=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJyk=
+github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=
+gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
diff --git a/validations.go b/validations.go
new file mode 100644
index 0000000..9fbae32
--- /dev/null
+++ b/validations.go
@@ -0,0 +1,97 @@
+package valiwork
+
+import (
+	// stdlib
+	"log"
+	"sync"
+
+	// local
+	"go.dev.pztrn.name/valiwork/validators"
+)
+
+var (
+	registeredValidators map[string]validators.ValidatorFunc
+	rvMutex              sync.RWMutex
+)
+
+// nolint
+func init() {
+	initializeValidatorsStorage()
+}
+
+func initializeValidatorsStorage() {
+	registeredValidators = make(map[string]validators.ValidatorFunc)
+}
+
+// RegisterValidator registers validation function for later calling.
+func RegisterValidator(validatorName string, validator validators.ValidatorFunc) error {
+	if DEBUG {
+		log.Println("Trying to register validator: '" + validatorName + "'...")
+	}
+
+	//rvMutex.RLock()
+	_, found := registeredValidators[validatorName]
+	//rvMutex.RUnlock()
+
+	if found {
+		if DEBUG {
+			log.Println("Validator already registered!")
+		}
+
+		return ErrValidatorAlreadyRegistered
+	}
+
+	//rvMutex.Lock()
+	registeredValidators[validatorName] = validator
+	//rvMutex.Unlock()
+
+	return nil
+}
+
+// UnregisterValidator removes registered validator from list of known
+// validators.
+func UnregisterValidator(validatorName string) error {
+	if DEBUG {
+		log.Println("Trying to unregister validator '" + validatorName + "'...")
+	}
+
+	//rvMutex.RLock()
+	_, found := registeredValidators[validatorName]
+	//rvMutex.RUnlock()
+
+	if !found {
+		if DEBUG {
+			log.Println("Validator wasn't registered!")
+		}
+
+		return ErrValidatorNotRegistered
+	}
+
+	//rvMutex.Lock()
+	delete(registeredValidators, validatorName)
+	//rvMutex.Unlock()
+
+	return nil
+}
+
+// Validate launches validation function and returns it's result to
+// caller.
+func Validate(validatorName string, thing interface{}, optional ...interface{}) []interface{} {
+	var errs []interface{}
+
+	//rvMutex.RLock()
+	validator, found := registeredValidators[validatorName]
+	//rvMutex.RUnlock()
+
+	if !found {
+		errs = append(errs, ErrValidatorNotRegistered)
+		return errs
+	}
+
+	errs1 := validator(thing, optional...)
+	if len(errs1) > 0 {
+		errs = append(errs, errs1...)
+	}
+
+	return errs
+}
diff --git a/validations_test.go b/validations_test.go
new file mode 100644
index 0000000..3f8b51a
--- /dev/null
+++ b/validations_test.go
@@ -0,0 +1,266 @@
+package valiwork
+
+import (
+	// stdlib
+	"errors"
+	"strconv"
+	"strings"
+	"sync"
+	"testing"
+
+	// local
+	"go.dev.pztrn.name/valiwork/validators"
+
+	// other
+	"github.com/stretchr/testify/require"
+)
+
+func TestRegisterValidator(t *testing.T) {
+	initializeValidatorsStorage()
+
+	testCases := []struct {
+		ValidatorName string
+		ValidatorFunc validators.ValidatorFunc
+		ShouldFail    bool
+	}{
+		{
+			ValidatorName: "string_test_validator",
+			ValidatorFunc: func(thing interface{}, optional ...interface{}) []interface{} {
+				return nil
+			},
+			ShouldFail: false,
+		},
+		// This case is about registering same validator function again.
+		{
+			ValidatorName: "string_test_validator",
+			ValidatorFunc: func(thing interface{}, optional ...interface{}) []interface{} {
+				return nil
+			},
+			ShouldFail: true,
+		},
+	}
+
+	for _, testCase := range testCases {
+		err := RegisterValidator(testCase.ValidatorName, testCase.ValidatorFunc)
+		if !testCase.ShouldFail {
+			require.Nil(t, err)
+		} else {
+			require.NotNil(t, err)
+		}
+	}
+}
+
+func BenchmarkRegisterValidator(b *testing.B) {
+	initializeValidatorsStorage()
+
+	for i := 0; i < b.N; i++ {
+		_ = RegisterValidator("string_test_validator_"+strconv.Itoa(i),
+			func(thing interface{}, optional ...interface{}) []interface{} {
+				return nil
+			},
+		)
+	}
+}
+
+func BenchmarkRegisterValidatorAsync(b *testing.B) {
+	initializeValidatorsStorage()
+
+	var w sync.WaitGroup
+
+	for i := 0; i < b.N; i++ {
+		w.Add(1)
+
+		go func() {
+			_ = RegisterValidator("string_test_validator_"+strconv.Itoa(i),
+				func(thing interface{}, optional ...interface{}) []interface{} {
+					return nil
+				},
+			)
+			w.Done()
+		}()
+
+		w.Wait()
+	}
+}
+
+func TestValidate(t *testing.T) {
+	initializeValidatorsStorage()
+
+	testString := " I am test string"
+
+	RegisterValidator("string_test1", func(thing interface{}, optional ...interface{}) []interface{} {
+		var errs []interface{}
+
+		stringToValidate, ok := thing.(string)
+		if !ok {
+			errs = append(errs, errors.New("not a string"))
+			return errs
+		}
+
+		if strings.HasPrefix(stringToValidate, " ") {
+			errs = append(errs, errors.New("string starts with whitespace, invalid!"))
+		}
+
+		return errs
+	})
+
+	errs := Validate("string_test1", testString, nil)
+	require.NotNil(t, errs)
+	require.Len(t, errs, 1)
+}
+
+func BenchmarkValidate(b *testing.B) {
+	b.StopTimer()
+
+	initializeValidatorsStorage()
+
+	testString := " I am test $tring"
+
+	RegisterValidator("string_test1", func(thing interface{}, optional ...interface{}) []interface{} {
+		var errs []interface{}
+
+		stringToValidate, ok := thing.(string)
+		if !ok {
+			errs = append(errs, errors.New("not a string"))
+			return errs
+		}
+
+		if strings.HasPrefix(stringToValidate, " ") {
+			errs = append(errs, errors.New("string starts with whitespace, invalid!"))
+		}
+
+		if strings.Contains(stringToValidate, "$") {
+			errs = append(errs, errors.New("string starts with whitespace, invalid!"))
+		}
+
+		return errs
+	})
+
+	b.StartTimer()
+
+	for i := 0; i < b.N; i++ {
+		_ = Validate("string_test1", testString)
+	}
+}
+
+func BenchmarkValidateAsync(b *testing.B) {
+	b.StopTimer()
+
+	initializeValidatorsStorage()
+
+	testString := " I am test $tring"
+
+	RegisterValidator("string_test1", func(thing interface{}, optional ...interface{}) []interface{} {
+		var errs []interface{}
+
+		stringToValidate, ok := thing.(string)
+		if !ok {
+			errs = append(errs, errors.New("not a string"))
+			return errs
+		}
+
+		if strings.HasPrefix(stringToValidate, " ") {
+			errs = append(errs, errors.New("string starts with whitespace, invalid!"))
+		}
+
+		if strings.Contains(stringToValidate, "$") {
+			errs = append(errs, errors.New("string starts with whitespace, invalid!"))
+		}
+
+		return errs
+	})
+
+	b.StartTimer()
+
+	var w sync.WaitGroup
+
+	for i := 0; i < b.N; i++ {
+		w.Add(1)
+
+		go func() {
+			_ = Validate("string_test1", testString)
+
+			w.Done()
+		}()
+
+		w.Wait()
+	}
+}
+
+func TestUnregisterValidator(t *testing.T) {
+	initializeValidatorsStorage()
+
+	testCases := []struct {
+		ValidatorName string
+		ValidatorFunc validators.ValidatorFunc
+	}{
+		{
+			ValidatorName: "string_test_validator",
+			ValidatorFunc: func(thing interface{}, optional ...interface{}) []interface{} {
+				return nil
+			},
+		},
+	}
+
+	for _, testCase := range testCases {
+		err := RegisterValidator(testCase.ValidatorName, testCase.ValidatorFunc)
+		require.Nil(t, err)
+
+		err1 := UnregisterValidator(testCase.ValidatorName)
+		require.Nil(t, err1)
+	}
+}
+
+func TestUnregisterValidatorNotRegisteredValidator(t *testing.T) {
+	initializeValidatorsStorage()
+
+	err := UnregisterValidator("this is definetely not registered thing")
+	require.NotNil(t, err)
+}
+
+func BenchmarkUnregisterValidator(b *testing.B) {
+	b.StopTimer()
+
+	initializeValidatorsStorage()
+
+	for i := 0; i < b.N; i++ {
+		_ = RegisterValidator("string_test_validator_"+strconv.Itoa(i),
+			func(thing interface{}, optional ...interface{}) []interface{} {
+				return nil
+			},
+		)
+	}
+
+	b.StartTimer()
+	for i := 0; i < b.N; i++ {
+		_ = UnregisterValidator("string_test_validator_" + strconv.Itoa(i))
+	}
+}
+
+func BenchmarkUnregisterValidatorAsync(b *testing.B) {
+	b.StopTimer()
+
+	initializeValidatorsStorage()
+
+	for i := 0; i < b.N; i++ {
+		_ = RegisterValidator("string_test_validator_"+strconv.Itoa(i),
+			func(thing interface{}, optional ...interface{}) []interface{} {
+				return nil
+			},
+		)
+	}
+
+	var w sync.WaitGroup
+
+	b.StartTimer()
+	for i := 0; i < b.N; i++ {
+		w.Add(1)
+
+		go func() {
+			_ = UnregisterValidator("string_test_validator_" + strconv.Itoa(i))
+			w.Done()
+		}()
+
+		w.Wait()
+	}
+}
diff --git a/validators/validator_signature.go b/validators/validator_signature.go
new file mode 100644
index 0000000..66f13e9
--- /dev/null
+++ b/validators/validator_signature.go
@@ -0,0 +1,4 @@
+package validators
+
+// ValidatorFunc represents signature for data validation function.
+type ValidatorFunc func(thing interface{}, optional ...interface{}) []interface{}