Extend filtering to use custom data (closes #176)

config/config.go

@@ -320,6 +320,18 @@ func (c *Config) GetTransformations() (transform.TransformationApplyFunction, er
 				return nil, err
 			}
 			funcs = append(funcs, filterFunc)
+		case "spEnrichedFilterContext":
+			filterFunc, err := transform.NewSpEnrichedFilterFunctionContext(funcOpts[1])
+			if err != nil {
+				return nil, err
+			}
+			funcs = append(funcs, filterFunc)
+		case "spEnrichedFilterUnstructEvent":
+			filterFunc, err := transform.NewSpEnrichedFilterFunctionUnstructEvent(funcOpts[1])
+			if err != nil {
+				return nil, err
+			}
+			funcs = append(funcs, filterFunc)
 		case "none":
 		default:
 			return nil, errors.New(fmt.Sprintf("Invalid transformation found; expected one of 'spEnrichedToJson', 'spEnrichedSetPk:{option}', spEnrichedFilter:{option} and got '%s'", c.Data.Transformation))

config/config_test.go

@@ -110,7 +110,7 @@ func TestNewConfig_FilterFailure(t *testing.T) {
 	transformation, err := c.GetTransformations()
 	assert.Nil(transformation)
 	assert.NotNil(err)
-	assert.Equal(`Invalid filter function config, must be of the format {field name}=={value}[|{value}|...] or {field name}!={value}[|{value}|...]`, err.Error())
+	assert.Equal(`invalid filter function config, must be of the format {field name}=={value}[|{value}|...] or {field name}!={value}[|{value}|...]`, err.Error())
 }
 
 func TestNewConfig_InvalidTarget(t *testing.T) {

go.mod

@@ -33,7 +33,6 @@ require (
 	github.com/smira/go-statsd v1.3.2
 	github.com/snowplow-devops/go-retry v0.0.0-20210106090855-8989bbdbae1c
 	github.com/snowplow-devops/go-sentryhook v0.0.0-20210106082031-21bf7f9dac2a
-	github.com/snowplow/snowplow-golang-analytics-sdk v0.1.0
 	github.com/stretchr/testify v1.7.0
 	github.com/twinj/uuid v1.0.0
 	github.com/twitchscience/kinsumer v0.0.0-20210611163023-da24975e2c91
@@ -54,6 +53,7 @@ require (
 require (
 	github.com/davecgh/go-spew v1.1.1
 	github.com/hashicorp/hcl/v2 v2.11.1
+	github.com/snowplow/snowplow-golang-analytics-sdk v0.2.2
 	github.com/zclconf/go-cty v1.10.0
 )
 

go.sum

@@ -131,8 +131,6 @@ github.com/aws/aws-sdk-go v1.25.19/go.mod h1:KmX6BPdI08NWTb3/sm4ZGu5ShLoqVDhKgpi
 github.com/aws/aws-sdk-go v1.40.22 h1:iit4tJ1hjL2GlNCrbE4aJza6jTmvEE2pDTnShct/yyY=
 github.com/aws/aws-sdk-go v1.40.22/go.mod h1:585smgzpB/KqRA+K3y/NL/oYRqQvpNJYvLm+LY1U59Q=
 github.com/aymerick/raymond v2.0.3-0.20180322193309-b565731e1464+incompatible/go.mod h1:osfaiScAUVup+UC9Nfq76eWqDhXlp+4UYaA8uhTBO6g=
-github.com/caarlos0/env/v6 v6.6.2 h1:BypLXDWQTA32rS4UM7pBz+/0BOuvs6C7LSeQAxMwyvI=
-github.com/caarlos0/env/v6 v6.6.2/go.mod h1:P0BVSgU9zfkxfSpFUs6KsO3uWR4k3Ac0P66ibAGTybM=
 github.com/caarlos0/env/v6 v6.9.1 h1:zOkkjM0F6ltnQ5eBX6IPI41UP/KDGEK7rRPwGCNos8k=
 github.com/caarlos0/env/v6 v6.9.1/go.mod h1:hvp/ryKXKipEkcuYjs9mI4bBCg+UI0Yhgm5Zu0ddvwc=
 github.com/cactus/go-statsd-client/statsd v0.0.0-20190922113730-52b467de415c/go.mod h1:D4RDtP0MffJ3+R36OkGul0LwJLIN8nRb0Ac6jZmJCmo=
@@ -208,6 +206,7 @@ github.com/go-gl/glfw v0.0.0-20190409004039-e6da0acd62b1/go.mod h1:vR7hzQXu2zJy9
 github.com/go-gl/glfw/v3.3/glfw v0.0.0-20191125211704-12ad95a8df72/go.mod h1:tQ2UAYgL5IevRw8kRxooKSPJfGvJ9fJQFa0TUsXzTg8=
 github.com/go-gl/glfw/v3.3/glfw v0.0.0-20200222043503-6f7a984d4dc4/go.mod h1:tQ2UAYgL5IevRw8kRxooKSPJfGvJ9fJQFa0TUsXzTg8=
 github.com/go-martini/martini v0.0.0-20170121215854-22fa46961aab/go.mod h1:/P9AEU963A2AYjv4d1V5eVL1CQbEJq6aCNHDDjibzu8=
+github.com/go-test/deep v1.0.3 h1:ZrJSEWsXzPOxaZnFteGEfooLba+ju3FYIbOrS+rQd68=
 github.com/go-test/deep v1.0.3/go.mod h1:wGDj63lr65AM2AQyKZd/NYHGb0R+1RLqB8NKt3aSFNA=
 github.com/gobwas/httphead v0.0.0-20180130184737-2c6c146eadee/go.mod h1:L0fX3K22YWvt/FAX9NnzrNzcI4wNYi9Yku4O0LKYflo=
 github.com/gobwas/pool v0.2.0/go.mod h1:q8bcK0KcYlCgd9e7WYLm9LpyS+YeLd8JVDW6WezmKEw=
@@ -379,12 +378,11 @@ github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
+github.com/kylelemons/godebug v0.0.0-20170820004349-d65d576e9348 h1:MtvEpTB6LX3vkb4ax0b5D2DHbNAUsen0Gx5wZoq3lV4=
 github.com/kylelemons/godebug v0.0.0-20170820004349-d65d576e9348/go.mod h1:B69LEHPfb2qLo0BaaOLcbitczOKLWTsrBG9LczfCD4k=
 github.com/labstack/echo/v4 v4.1.11/go.mod h1:i541M3Fj6f76NZtHSj7TXnyM8n2gaodfvfxNnFqi74g=
 github.com/labstack/gommon v0.3.0/go.mod h1:MULnywXg0yavhxWKc+lOruYdAhDwPK9wf0OL7NoOu+k=
 github.com/magiconair/properties v1.8.0/go.mod h1:PppfXfuXeibc/6YijjN8zIbojt8czPbwD3XqdrwzmxQ=
-github.com/matryer/is v1.4.0 h1:sosSmIWwkYITGrxZ25ULNDeKiMNzFSr4V/eqBQP0PeE=
-github.com/matryer/is v1.4.0/go.mod h1:8I/i5uYgLzgsgEloJE1U6xx5HkBQpAZvepWuujKwMRU=
 github.com/mattn/go-colorable v0.1.2/go.mod h1:U0ppj6V5qS13XJ6of8GYAs25YV2eR4EVcfRqFIhoBtE=
 github.com/mattn/go-isatty v0.0.7/go.mod h1:Iq45c/XA43vh69/j3iqttzPXn0bhXyGjM0Hdxcsrc5s=
 github.com/mattn/go-isatty v0.0.8/go.mod h1:Iq45c/XA43vh69/j3iqttzPXn0bhXyGjM0Hdxcsrc5s=
@@ -441,6 +439,7 @@ github.com/russross/blackfriday/v2 v2.1.0 h1:JIOH55/0cWyOuilr9/qlrm0BSXldqnqwMsf
 github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
 github.com/ryanuber/columnize v2.1.0+incompatible/go.mod h1:sm1tb6uqfes/u+d4ooFouqFdy9/2g9QGwK3SQygK0Ts=
 github.com/schollz/closestmatch v2.1.0+incompatible/go.mod h1:RtP1ddjLong6gTkbtmuhtR2uUrrJOpYzYRvbcPAid+g=
+github.com/sergi/go-diff v1.0.0 h1:Kpca3qRNrduNnOQeazBd0ysaKrUJiIuISHxogkT9RPQ=
 github.com/sergi/go-diff v1.0.0/go.mod h1:0CfEIISq7TuYL3j771MWULgwwjU+GofnZX9QAmXWZgo=
 github.com/shurcooL/sanitized_anchor_name v1.0.0/go.mod h1:1NzhyTcUVG4SuEtjjoZeVRXNmyL/1OwPU0+IJeTBvfc=
 github.com/sirupsen/logrus v1.2.0/go.mod h1:LxeOpSwHxABJmUn/MG1IvRgCAasNZTLOkJPxbbu5VWo=
@@ -457,8 +456,8 @@ github.com/snowplow-devops/go-sentryhook v0.0.0-20210106082031-21bf7f9dac2a h1:9
 github.com/snowplow-devops/go-sentryhook v0.0.0-20210106082031-21bf7f9dac2a/go.mod h1:7/jMxl0yrvgiUlv5L37fw6pql71aNh55sKQc4kBFj5s=
 github.com/snowplow-devops/kinsumer v1.3.0 h1:uN8PPG8EffKjcfTcDqsHWnnsTFvYGMU39XlDPULIQcA=
 github.com/snowplow-devops/kinsumer v1.3.0/go.mod h1:SebvcasLweQnOygk9SOFkM/JjBtXFviUxoAq19CwrHQ=
-github.com/snowplow/snowplow-golang-analytics-sdk v0.1.0 h1:FA8xHSHzoshF3fJDK9tqUDnuBmyqTiGPRLvIaRQMk2I=
-github.com/snowplow/snowplow-golang-analytics-sdk v0.1.0/go.mod h1:Z8ZW805JGCYhnq1wnHe2PIiamUnvoNtAtXPWNyS0mV8=
+github.com/snowplow/snowplow-golang-analytics-sdk v0.2.2 h1:ehPNYJ4tOq+n4Lj8jtentKS4UzzvRv5iQ8vlESQj8qw=
+github.com/snowplow/snowplow-golang-analytics-sdk v0.2.2/go.mod h1:Z8ZW805JGCYhnq1wnHe2PIiamUnvoNtAtXPWNyS0mV8=
 github.com/spaolacci/murmur3 v0.0.0-20180118202830-f09979ecbc72/go.mod h1:JwIasOWyU6f++ZhiEuf87xNszmSA2myDM2Kzu9HwQUA=
 github.com/spf13/afero v1.1.2/go.mod h1:j4pytiNVoe2o6bmDsKpLACNPDBIoEAkihy7loJ1B0CQ=
 github.com/spf13/cast v1.3.0/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkUJE=

pkg/transform/snowplow_enriched_filter.go

@@ -13,21 +13,67 @@ import (
 	"strings"
 
 	"github.com/snowplow-devops/stream-replicator/pkg/models"
+	"github.com/snowplow/snowplow-golang-analytics-sdk/analytics"
 )
 
-// NewSpEnrichedFilterFunction returns a TransformationFunction which filters messages based on a field in the Snowplow enriched event.
+func findSpEnrichedFilterValue(queriedField, parsedEventName, eventVer, field string, parsedMessage analytics.ParsedEvent, path []interface{}) ([]interface{}, error) {
+	var vf interface{}
+	var valueFound []interface{}
+	var err error
+
+	switch {
+	case strings.HasPrefix(queriedField, `contexts_`):
+		vf, err = parsedMessage.GetContextValue(queriedField, path...)
+		valueFound = append(valueFound, vf.([]interface{})...)
+	case strings.HasPrefix(queriedField, `unstruct_event`):
+		eventNameFull := `unstruct_event_` + parsedEventName
+		if queriedField == eventNameFull || queriedField == eventNameFull+`_`+eventVer {
+			vf, err = parsedMessage.GetUnstructEventValue(path...)
+			valueFound = append(valueFound, vf)
+		}
+	default:
+		vf, err = parsedMessage.GetValue(field)
+		valueFound = append(valueFound, vf)
+	}
+	if err != nil {
+		// GetValue returns an error if the field requested is empty. Check for that particular error before returning error
+		if err.Error() == analytics.EmptyFieldErr {
+			return nil, nil
+		}
+		return nil, err
+	}
+	return valueFound, nil
+}
+
+func evaluateSpEnrichedFilter(valuesToMatch string, valuesFound []interface{}, isNegationFilter, shouldKeepMessage *bool) {
+	for _, valueToMatch := range strings.Split(valuesToMatch, "|") {
+		for _, v := range valuesFound {
+			if fmt.Sprintf("%v", v) == valueToMatch {
+				// Once config value is matched once, change shouldKeepMessage, and stop looking for matches
+				if *isNegationFilter {
+					*shouldKeepMessage = false
+				} else {
+					*shouldKeepMessage = true
+				}
+				return
+
+			}
+		}
+	}
+}
+
+// createSpEnrichedFilterFunction returns a TransformationFunction which filters messages based on a field in the Snowplow enriched event.
 // The filterconfig should describe the conditions for including a message.
 // For example "aid=abc|def" includes all events with app IDs of abc or def, and filters out the rest.
 // aid!=abc|def includes all events whose app IDs do not match abc or def, and filters out the rest.
-func NewSpEnrichedFilterFunction(filterConfig string) (TransformationFunction, error) {
-
+func createSpEnrichedFilterFunction(filterConfig string, isUnstructEvent bool, isContext bool) (TransformationFunction, error) {
 	// This regex prevents whitespace characters in the value provided
 	regex := `\S+(!=|==)[^\s\|]+((?:\|[^\s|]+)*)$`
 	re := regexp.MustCompile(regex)
 
 	if !(re.MatchString(filterConfig)) {
 		// If invalid, return an error which will be returned by the main function
-		return nil, errors.New("Invalid filter function config, must be of the format {field name}=={value}[|{value}|...] or {field name}!={value}[|{value}|...]")
+		return nil, errors.New("invalid filter function config, must be of the format {field name}=={value}[|{value}|...] or {field name}!={value}[|{value}|...]")
 	}
 
 	// Check for a negation condition first
@@ -48,43 +94,90 @@ func NewSpEnrichedFilterFunction(filterConfig string) (TransformationFunction, e
 		// Start by resetting shouldKeepMessage to isNegationFilter
 		shouldKeepMessage := isNegationFilter
 
-		// Evalute intermediateState to parsedEvent
+		// Evaluate intermediateState to parsedEvent
 		parsedMessage, parseErr := intermediateAsSpEnrichedParsed(intermediateState, message)
 		if parseErr != nil {
 			message.SetError(parseErr)
 			return nil, nil, message, nil
 		}
 
-		valueFound, err := parsedMessage.GetValue(keyValues[0])
+		// This regex retrieves the path fields
+		// (e.g. field1.field2[0].field3 -> [field1, field2, 0, field3])
+		regex = `\w+`
+		re = regexp.MustCompile(regex)
 
-		// GetValue returns an error if the field requested is empty. Check for that particular error before failing the message.
-		if err != nil && err.Error() == fmt.Sprintf("Field %s is empty", keyValues[0]) {
-			valueFound = nil
-		} else if err != nil {
-			message.SetError(err)
-			return nil, nil, message, nil
+		// separate the path string into words using regex
+		path := re.FindAllString(keyValues[0], -1)
+		separatedPath := make([]string, len(path)-1)
+		for idx, pathField := range path[1:] {
+			separatedPath[idx] = pathField
 		}
 
-	evaluation:
-		for _, valueToMatch := range strings.Split(keyValues[1], "|") {
-			if valueToMatch == fmt.Sprintf("%v", valueFound) { // coerce to string as valueFound may be any type found in a Snowplow event
-				if isNegationFilter {
-					shouldKeepMessage = false
-				} else {
-					shouldKeepMessage = true
-				}
-				break evaluation
-				// Once config value is matched once, change shouldKeepMessage, and stop looking for matches
+		var parsedEventName string
+		var eventMajorVer string
+		var err error
+
+		// only call SDK functions if an unstruct_event is being filtered
+		if isUnstructEvent {
+			// get event name
+			eventName, err := parsedMessage.GetValue(`event_name`)
+			if err != nil {
+				message.SetError(err)
+				return nil, nil, message, nil
+			}
+			parsedEventName = eventName.(string)
+			// get event version
+			fullEventVer, err := parsedMessage.GetValue(`event_version`)
+			if err != nil {
+				message.SetError(err)
+				return nil, nil, message, nil
+			}
+			// get the major event version
+			eventMajorVer = strings.Split(fullEventVer.(string), `-`)[0]
+			if eventMajorVer == `` {
+				message.SetError(fmt.Errorf(`invalid schema version format: %s`, fullEventVer))
+				return nil, nil, message, nil
 			}
 		}
 
-		// If message is not to be kept, return it as a filtered message to be acked in the main function
-		if !shouldKeepMessage {
+		// find the value in the event
+		valueFound, err := findSpEnrichedFilterValue(
+			path[0],
+			parsedEventName,
+			eventMajorVer,
+			keyValues[0],
+			parsedMessage,
+			convertPathToInterfaces(separatedPath),
+		)
+		if err != nil {
+			message.SetError(err)
+			return nil, nil, message, nil
+		}
+
+		// evaluate whether the found value passes the filter, determining if the message should be kept
+		evaluateSpEnrichedFilter(keyValues[1], valueFound, &isNegationFilter, &shouldKeepMessage)
 
+		// if message is not to be kept, return it as a filtered message to be acked in the main function
+		if !shouldKeepMessage {
 			return nil, message, nil, nil
 		}
 
-		// Otherwise, return the message and intermediateState for further processing.
+		// otherwise, return the message and intermediateState for further processing.
 		return message, nil, nil, parsedMessage
 	}, nil
 }
+
+// NewSpEnrichedFilterFunction returns a TransformationFunction which filters messages based on a field in the Snowplow enriched event.
+func NewSpEnrichedFilterFunction(filterConfig string) (TransformationFunction, error) {
+	return createSpEnrichedFilterFunction(filterConfig, false, false)
+}
+
+// NewSpEnrichedFilterFunctionContext returns a TransformationFunction for filtering a context
+func NewSpEnrichedFilterFunctionContext(filterConfig string) (TransformationFunction, error) {
+	return createSpEnrichedFilterFunction(filterConfig, false, true)
+}
+
+// NewSpEnrichedFilterFunctionUnstructEvent returns a TransformationFunction for filtering an unstruct_event
+func NewSpEnrichedFilterFunctionUnstructEvent(filterConfig string) (TransformationFunction, error) {
+	return createSpEnrichedFilterFunction(filterConfig, true, false)
+}

pkg/transform/snowplow_enriched_filter_test.go

@@ -21,6 +21,16 @@ func TestNewSpEnrichedFilterFunction(t *testing.T) {
 		PartitionKey: "some-key",
 	}
 
+	var messageGoodInt = models.Message{
+		Data:         snowplowTsv4,
+		PartitionKey: "some-key",
+	}
+
+	var messageWithUnstructEvent = models.Message{
+		Data:         snowplowTsv1,
+		PartitionKey: "some-key",
+	}
+
 	// Single value cases
 	aidFilterFuncKeep, _ := NewSpEnrichedFilterFunction("app_id==test-data3")
 
@@ -116,11 +126,74 @@ func TestNewSpEnrichedFilterFunction(t *testing.T) {
 	assert.Equal(snowplowTsv3, nilNegationIn.Data)
 	assert.Nil(nilNegationOut)
 	assert.Nil(fail8)
+
+	// context filter success
+	contextFuncKeep, _ := NewSpEnrichedFilterFunctionContext("contexts_nl_basjes_yauaa_context_1.test1.test2[0].test3==testValue")
+
+	contextKeepIn, contextKeepOut, fail9, _ := contextFuncKeep(&messageGood, nil)
+
+	assert.Equal(snowplowTsv3, contextKeepIn.Data)
+	assert.Nil(contextKeepOut)
+	assert.Nil(fail9)
+
+	// context filter success (integer value)
+	contextFuncKeep, _ = NewSpEnrichedFilterFunctionContext("contexts_nl_basjes_yauaa_context_1.test1.test2[0].test3==1")
+
+	contextKeepIn, contextKeepOut, fail9, _ = contextFuncKeep(&messageGoodInt, nil)
+
+	assert.Equal(snowplowTsv4, contextKeepIn.Data)
+	assert.Nil(contextKeepOut)
+	assert.Nil(fail9)
+
+	// context filter failure
+	contextFuncKeep, _ = NewSpEnrichedFilterFunctionContext("contexts_nl_basjes_yauaa_context_2.test1.test2[0].test3==testValue")
+
+	contextKeepIn, contextKeepOut, fail9, _ = contextFuncKeep(&messageGood, nil)
+
+	assert.Nil(contextKeepIn)
+	assert.Equal(snowplowTsv3, contextKeepOut.Data)
+	assert.Nil(fail9)
+
+	// event filter success, filtered event name
+	eventFilterFunCkeep, _ := NewSpEnrichedFilterFunctionUnstructEvent("unstruct_event_add_to_cart_1.sku==item41")
+
+	eventKeepIn, eventKeepOut, fail10, _ := eventFilterFunCkeep(&messageWithUnstructEvent, nil)
+
+	assert.Equal(snowplowTsv1, eventKeepIn.Data)
+	assert.Nil(eventKeepOut)
+	assert.Nil(fail10)
+
+	// event filter success, filtered event name, no event ver
+	eventFilterFunCkeep, _ = NewSpEnrichedFilterFunctionUnstructEvent("unstruct_event_add_to_cart.sku==item41")
+
+	eventKeepIn, eventKeepOut, fail10, _ = eventFilterFunCkeep(&messageWithUnstructEvent, nil)
+
+	assert.Equal(snowplowTsv1, eventKeepIn.Data)
+	assert.Nil(eventKeepOut)
+	assert.Nil(fail10)
+
+	// event filter failure, wrong event name
+	eventFilterFunCkeep, _ = NewSpEnrichedFilterFunctionUnstructEvent("unstruct_event_wrong_name.sku==item41")
+
+	eventKeepIn, eventKeepOut, fail11, _ := eventFilterFunCkeep(&messageWithUnstructEvent, nil)
+
+	assert.Nil(eventKeepIn)
+	assert.Equal(snowplowTsv1, eventKeepOut.Data)
+	assert.Nil(fail11)
+
+	// event filter failure, field not found
+	eventFilterFunCkeep, _ = NewSpEnrichedFilterFunctionUnstructEvent("unstruct_event_add_to_cart.ska==item41")
+
+	eventNoFieldIn, eventNoFieldOut, fail12, _ := eventFilterFunCkeep(&messageWithUnstructEvent, nil)
+
+	assert.Nil(eventNoFieldIn)
+	assert.Nil(eventNoFieldOut)
+	assert.NotNil(fail12)
 }
 
 func TestNewSpEnrichedFilterFunction_Error(t *testing.T) {
 	assert := assert.New(t)
-	error := `Invalid filter function config, must be of the format {field name}=={value}[|{value}|...] or {field name}!={value}[|{value}|...]`
+	error := `invalid filter function config, must be of the format {field name}=={value}[|{value}|...] or {field name}!={value}[|{value}|...]`
 
 	filterFunc, err1 := NewSpEnrichedFilterFunction("")
 

pkg/transform/snowplow_enriched_util.go

@@ -9,6 +9,7 @@ package transform
 import (
 	"github.com/snowplow-devops/stream-replicator/pkg/models"
 	"github.com/snowplow/snowplow-golang-analytics-sdk/analytics"
+	"strconv"
 )
 
 func intermediateAsSpEnrichedParsed(intermediateState interface{}, message *models.Message) (analytics.ParsedEvent, error) {
@@ -23,3 +24,18 @@ func intermediateAsSpEnrichedParsed(intermediateState interface{}, message *mode
 	}
 	return parsedMessage, nil
 }
+
+// convertPathToInterfaces converts a slice of strings representing a path to a slice of interfaces to be used
+// by the SDK Get() function
+func convertPathToInterfaces(path []string) []interface{} {
+	var output []interface{}
+	for _, pathField := range path {
+		pathFieldInt, err := strconv.Atoi(pathField)
+		if err != nil {
+			output = append(output, pathField)
+		} else {
+			output = append(output, pathFieldInt)
+		}
+	}
+	return output
+}