sumOf customKeyword

Taskfile.yml

@@ -31,6 +31,7 @@ tasks:
                     --verbose \
                     --data \
                     -c ajv-keywords \
+                    -c ./src/sumOf.cjs \
                     -r schemas-json/classes.json \
                     -s schemas-json/character.json \
                     -d {{.CLI_ARGS}}

package.json

@@ -21,6 +21,8 @@
   "dependencies": {
     "ajv": "^8.11.0",
     "ajv-cli": "^5.0.0",
-    "ajv-keywords": "^5.1.0"
+    "ajv-keywords": "^5.1.0",
+    "json-pointer": "^0.6.2",
+    "lodash": "^4.17.21"
   }
 }

schemas-json/character.json

@@ -19,6 +19,11 @@
                "type" : "array"
             },
             "max" : {
+               "sumOf" : {
+                  "list" : {
+                     "$data" : "1/log"
+                  }
+               },
                "type" : "number"
             }
          },

schemas-yaml/character.yml

@@ -13,20 +13,20 @@ properties:
   name: &string
     type: string
   player: *string
-    class: { $ref: '/classes.json' }
+  class: { $ref: "/classes.json" }
   statistics:
     type: object
     allRequired: true
     properties:
       strength: &stat
-          $ref: '#/$defs/statistic'
+        $ref: "#/$defs/statistic"
       dexterity: *stat
       constitution: *stat
       intelligence: *stat
       wisdom: *stat
       charisma: *stat
   level: { type: number, minimum: 1 }
-    health: { $ref: '#/$defs/health' }
+  health: { $ref: "#/$defs/health" }
 $defs:
   statistic:
     type: number
@@ -36,7 +36,9 @@ $defs:
     type: object
     required: [max]
     properties:
-        max: { type: number }
+      max:
+        type: number
+        sumOf: { list: { $data: 1/log } }
       current: { type: number }
       log:
         type: array
@@ -44,4 +46,3 @@ $defs:
         items: { type: number }
         minItems: { $data: /level }
         maxItems: { $data: /level }
-

src/sumOf.cjs

@@ -0,0 +1,47 @@
+const _ = require("lodash");
+const ptr = require("json-pointer");
+
+function resolvePointer(data, rootPath, relativePath) {
+    if (relativePath[0] === "/") return ptr.get(data, relativePath);
+
+    const m = relativePath.match(/^(\d+)(.*)/);
+    relativePath = m[2];
+    for (let i = 0; i < parseInt(m[1]); i++) {
+        rootPath = rootPath.replace(/\/[^\/]+$/, "");
+    }
+
+    return ptr.get(data, rootPath + relativePath);
+}
+
+module.exports = (ajv) =>
+    ajv.addKeyword({
+        keyword: "sumOf",
+        validate: function validate(
+            { list, map },
+            total,
+            _parent,
+            { rootData, instancePath }
+        ) {
+            if (list.$data) {
+                list = resolvePointer(rootData, instancePath, list.$data);
+            }
+
+            if (map) data = _.map(data, map);
+
+            if (_.sum(list) === total) return true;
+
+            validate.errors = [
+                {
+                    keyword: "sumOf",
+                    message: "should add up to sum total",
+                    params: {
+                        list,
+                    },
+                },
+            ];
+
+            return false;
+        },
+        $data: true,
+        errors: true,
+    });