add scripts for computing stats of json schemas

scripts/jsonschema-stats.js

@@ -0,0 +1,91 @@
+const ignored = [
+    "$schema",
+    "$id",
+    "id",
+    "$comment",
+    "title",
+    "description",
+    "default",
+    "examples",
+    "required",
+]
+
+const defs = [
+    "definitions",
+    "$defs",
+]
+
+let numFields = 0;
+
+function typeStats(obj) {
+    if (typeof obj === "boolean")
+        return;
+
+    if (typeof obj === "object" && Object.keys(obj).length == 0)
+        return;
+
+    numFields++;
+
+    if (Array.isArray(obj)) {
+        for (const v of obj) {
+            typeStats(v);
+        }
+        return;
+    }
+
+    if (typeof obj !== "object") {
+        console.log("not object", obj);
+        return;
+    }
+
+    const obj0 = { ...obj }
+
+    const tp = obj.type;
+
+    if (!tp) {
+        if (obj["$ref"] && obj["$ref"].startsWith("#/"))
+            return; // OK
+        console.log("no type", obj);
+        return;
+    }
+
+
+    if (tp == "object") {
+        const props = obj.properties || {};
+        Object.values(props).forEach(typeStats);
+        delete obj.properties;
+    }
+
+    if (tp == "array") {
+        typeStats(obj.items);
+        delete obj.items;
+    }
+
+    if (obj.additionalProperties !== undefined) {
+        typeStats(obj.additionalProperties);
+        delete obj.additionalProperties;
+    }
+
+    for (const def of defs) {
+        if (obj[def]) {
+            Object.values(obj[def]).forEach(typeStats);
+            delete obj[def];
+        }
+    }
+
+    for (const ign of ignored) {
+        delete obj[ign];
+    }
+
+    if (Object.keys(obj).length > 1) {
+        console.log("left-over", JSON.stringify(obj));
+    }
+}
+
+
+const fs = require('fs');
+
+const schema = JSON.parse(fs.readFileSync(process.argv[2], 'utf8'));
+
+typeStats(schema);
+console.log({ numFields });