Merge pull request #14 from drone/version_check_and_priority_rules_fix

[MAINT] minor fixes

Author: enver-bisevac

__tests__/usecases/rules_priority.json

@@ -0,0 +1,77 @@
+{
+  "flag": {
+    "defaultServe": { "distribution": null, "variation": "true" },
+    "environment": "demoenv",
+    "feature": "AlfaTest",
+    "kind": "boolean",
+    "offVariation": "false",
+    "prerequisites": [],
+    "project": "FeatureFlagsDemo",
+    "rules": [
+      {
+        "ruleId": "",
+        "priority": 1000,
+        "clauses": [
+          {
+            "id": "",
+            "attribute": "identifier",
+            "op": "equal",
+            "values": ["harness"]
+          }
+        ],
+        "serve": {
+          "distribution": null,
+          "variation": "true"
+        }
+      },
+      {
+        "ruleId": "",
+        "priority": 999,
+        "clauses": [
+          {
+            "id": "",
+            "attribute": "identifier",
+            "op": "equal",
+            "values": ["harness"]
+          }
+        ],
+        "serve": {
+          "distribution": null,
+          "variation": "false"
+        }
+      }
+    ],
+    "state": "on",
+    "variationToTargetMap": null,
+    "variations": [
+      {
+        "description": null,
+        "identifier": "true",
+        "name": "Enable Page",
+        "value": "true"
+      },
+      {
+        "description": null,
+        "identifier": "false",
+        "name": "Disable Page",
+        "value": "false"
+      }
+    ]
+  },
+  "targets": [
+    {
+      "identifier": "harness",
+      "name": "Harness"
+    },
+    {
+      "identifier": "enver",
+      "attributes": {
+        "email": "[email protected]"
+      }
+    }
+  ],
+  "expected": {
+    "_no_target": true,
+    "harness": false
+  }
+}

src/evaluator.ts

@@ -216,6 +216,11 @@ export class Evaluator {
     if (!target || !rules) {
       return undefined;
     }
+
+    rules.sort((a: ServingRule, b: ServingRule) =>
+      a.priority > b.priority ? 1 : -1,
+    );
+
     let identifier: string;
     for (const rule of rules) {
       // if evaluation is false just continue to next rule

src/repository.ts

@@ -25,6 +25,9 @@ export class StorageRepository implements Repository {
 
   setFlag(identifier: string, fc: FeatureConfig): void {
     const flagKey = this.formatFlagKey(identifier);
+    if (this.isFlagOutdated(flagKey, fc)) {
+      return;
+    }
     if (this.store) {
       this.store.set(flagKey, fc);
       this.cache.del(flagKey);
@@ -35,6 +38,9 @@ export class StorageRepository implements Repository {
 
   setSegment(identifier: string, segment: Segment): void {
     const segmentKey = this.formatSegmentKey(identifier);
+    if (this.isSegmentOutdated(segmentKey, segment)) {
+      return;
+    }
     if (this.store) {
       this.store.set(segmentKey, segment);
       this.cache.del(segmentKey);
@@ -59,38 +65,48 @@ export class StorageRepository implements Repository {
     this.cache.del(segmentKey);
   }
 
-  getFlag(identifier: string): FeatureConfig {
+  getFlag(identifier: string, cacheable = true): FeatureConfig {
     const flagKey = this.formatFlagKey(identifier);
     let flag = this.cache.get(flagKey) as FeatureConfig;
     if (flag) {
       return flag;
     }
     if (this.store) {
       flag = this.store.get(flagKey) as FeatureConfig;
-      if (flag) {
+      if (flag && cacheable) {
         this.cache.set(flagKey, flag);
       }
       return flag;
     }
     return undefined;
   }
 
-  getSegment(identifier: string): Segment {
+  getSegment(identifier: string, cacheable = true): Segment {
     const segmentKey = this.formatSegmentKey(identifier);
     let segment = this.cache.get(segmentKey) as Segment;
     if (segment) {
       return segment;
     }
     if (this.store) {
       segment = this.store.get(segmentKey) as Segment;
-      if (segment) {
+      if (segment && cacheable) {
         this.cache.set(segmentKey, segment);
       }
       return segment;
     }
     return undefined;
   }
 
+  private isFlagOutdated(key: string, flag: FeatureConfig): boolean {
+    const oldFlag = this.getFlag(key, false); // dont set cacheable, we are just checking the version
+    return oldFlag?.version && oldFlag.version > flag?.version;
+  }
+
+  private isSegmentOutdated(key: string, segment: Segment): boolean {
+    const oldSegment = this.getSegment(key, false); // dont set cacheable, we are just checking the version
+    return oldSegment?.version && oldSegment.version > segment?.version;
+  }
+
   private formatFlagKey(key: string): string {
     return `flags/${key}`;
   }