feat: standalone targeting, fractional shorthand (#168)

This PR does 2 things:

- Allows for fractional targeting shorthand where no weight (assumes
weight = 1)
- Allows the targeting.json schema to be used alone, not just as part of
the flag definition schema

Non functionally, it restructures our testing so that tests pertaining
to `targeting.json` exist in the `test/targeting/` dir, while tests
pertaining to the `flags.json` exist in the `test/flags` dir.

Fixes: #165

---------

Signed-off-by: Todd Baert <todd.baert@dynatrace.com>

Author: toddbaert

json/flagd_definitions_test.go

@@ -13,34 +13,51 @@ import (
 	"github.com/xeipuuv/gojsonschema"
 )
 
-var compiledSchema *gojsonschema.Schema
+var compiledFlagDefinitionSchema *gojsonschema.Schema
+var compiledTargetingSchema *gojsonschema.Schema
 
 func init() {
-	schemaLoader := gojsonschema.NewSchemaLoader()
-	schemaLoader.AddSchemas(gojsonschema.NewStringLoader(flagd_definitions.TargetingSchema))
+	flagDefinitionSchemaLoader := gojsonschema.NewSchemaLoader()
+	flagDefinitionSchemaLoader.AddSchemas(gojsonschema.NewStringLoader(flagd_definitions.TargetingSchema))
+	targetingSchemaLoader := gojsonschema.NewSchemaLoader()
 	var err error
-	compiledSchema, err = schemaLoader.Compile(gojsonschema.NewStringLoader(flagd_definitions.FlagSchema))
+	compiledFlagDefinitionSchema, err = flagDefinitionSchemaLoader.Compile(gojsonschema.NewStringLoader(flagd_definitions.FlagSchema))
+	compiledTargetingSchema, err = targetingSchemaLoader.Compile(gojsonschema.NewStringLoader(flagd_definitions.TargetingSchema))
 	if err != nil {
 		message := fmt.Errorf("err: %v", err)
 		log.Fatal(message)
 	}
 }
 
-func TestPositiveParsing(t *testing.T) {
-	if err := walkPath(true, "./test/positive"); err != nil {
+func TestPositiveFlagParsing(t *testing.T) {
+	if err := walkPath(true, "./test/flags/positive", compiledFlagDefinitionSchema); err != nil {
 		t.Error(err)
 		t.FailNow()
 	}
 }
 
-func TestNegativeParsing(t *testing.T) {
-	if err := walkPath(false, "./test/negative"); err != nil {
+func TestNegativeFlagParsing(t *testing.T) {
+	if err := walkPath(false, "./test/flags/negative", compiledFlagDefinitionSchema); err != nil {
 		t.Error(err)
 		t.FailNow()
 	}
 }
 
-func walkPath(shouldPass bool, root string) error {
+func TestPositiveTargetingParsing(t *testing.T) {
+	if err := walkPath(true, "./test/targeting/positive", compiledTargetingSchema); err != nil {
+		t.Error(err)
+		t.FailNow()
+	}
+}
+
+func TestNegativeTargetingParsing(t *testing.T) {
+	if err := walkPath(false, "./test/targeting/negative", compiledTargetingSchema); err != nil {
+		t.Error(err)
+		t.FailNow()
+	}
+}
+
+func walkPath(shouldPass bool, root string, schema *gojsonschema.Schema) error {
 	return filepath.Walk(root, func(path string, info os.FileInfo, err error) error {
 		if err != nil {
 			return err
@@ -56,7 +73,7 @@ func walkPath(shouldPass bool, root string) error {
 
 		flagStringLoader := gojsonschema.NewStringLoader(string(file))
 
-		p, err := compiledSchema.Validate(flagStringLoader)
+		p, err := schema.Validate(flagStringLoader)
 		if err != nil {
 			return err
 		}

json/flags.json

@@ -2,7 +2,7 @@
   "$id": "https://flagd.dev/schema/v0/flags.json",
   "$schema": "http://json-schema.org/draft-07/schema#",
   "title": "flagd Flag Configuration",
-  "description": "Defines flags for use in flagd, including typed variants and rules",
+  "description": "Defines flags for use in flagd, including typed variants and rules.",
   "type": "object",
   "properties": {
     "flags": {
@@ -46,7 +46,7 @@
       "patternProperties": {
         "^.{1,}$": {
           "$comment": "this relative ref means that targeting.json MUST be in the same dir, or available on the same HTTP path",
-          "$ref": "./targeting.json#/definitions/targeting"
+          "$ref": "./targeting.json"
         }
       }
     }
@@ -71,7 +71,7 @@
           "type": "string"
         },
         "targeting": {
-          "$ref": "./targeting.json#/definitions/targeting"
+          "$ref": "./targeting.json"
         }
       },
       "required": [

json/flags.yaml

@@ -1,7 +1,7 @@
 $id: "https://flagd.dev/schema/v0/flags.json"
 $schema: http://json-schema.org/draft-07/schema#
 title: flagd Flag Configuration
-description: Defines flags for use in flagd, including typed variants and rules
+description: Defines flags for use in flagd, including typed variants and rules.
 type: object
 properties:
   flags:
@@ -35,7 +35,7 @@ properties:
       "^.{1,}$":
         $comment: this relative ref means that targeting.json MUST be in the same
           dir, or available on the same HTTP path
-        $ref: "./targeting.json#/definitions/targeting"
+        $ref: "./targeting.json"
 definitions:
   flag:
     $comment: base flag object; no title/description here, allows for better UX,
@@ -56,7 +56,7 @@ definitions:
           if the targeting returns null).
         type: string
       targeting:
-        $ref: "./targeting.json#/definitions/targeting"
+        $ref: "./targeting.json"
     required:
     - state
     - defaultVariant

json/targeting.json

@@ -2,24 +2,20 @@
   "$id": "https://flagd.dev/schema/v0/targeting.json",
   "$schema": "http://json-schema.org/draft-07/schema#",
   "title": "flagd Targeting",
-  "description": "Defines targeting logic for flagd; a extension of JSONLogic, including purpose-built feature-flagging operations.",
+  "description": "Defines targeting logic for flagd; a extension of JSONLogic, including purpose-built feature-flagging operations. Note that this schema applies to top-level objects; no additional properties are supported, including \"$schema\", which means built-in JSON-schema support is not possible in editors. Please use flags.json (which imports this schema) for a rich editor experience.",
   "type": "object",
-  "definitions": {
-    "targeting": {
-      "title": "Targeting",
-      "description": "An expression returning a value which is coerced to a string to be used as a targeting key, or null (to fall back to defaultVariant). If targeting returns a value which is not a variant key, it's considered an error.",
-      "anyOf": [
-        {
-          "$comment": "we need this to support empty targeting",
-          "type": "object",
-          "additionalProperties": false,
-          "properties": {}
-        },
-        {
-          "$ref": "#/definitions/anyRule"
-        }
-      ]
+  "anyOf": [
+    {
+      "$comment": "we need this to support empty targeting",
+      "type": "object",
+      "additionalProperties": false,
+      "properties": {}
     },
+    {
+      "$ref": "#/definitions/anyRule"
+    }
+  ],
+  "definitions": {
     "primitive": {
       "oneOf": [
         {
@@ -462,7 +458,7 @@
       "$comment": "if we remove the \"sum to 100\" restriction, update the descriptions below!",
       "description": "Distribution for all possible variants, with their associated weighting out of 100.",
       "type": "array",
-      "minItems": 2,
+      "minItems": 1,
       "maxItems": 2,
       "items": [
         {