chore: store schema version inside package (#96)

(Take 2 of #62).

Currently, the schema version espoused by this package is the package version itself (i.e., the version of its own `package.json`). Move this version to a resource file that maintained inside the package and is bumped explicitly.

In a projen (mono)repo, all packages have version 0.0.0. At development time, the Cloud Assembly Schema has to know its own version, for various versioning checks. It can’t get it from the package version (which is 0.0.0, so it needs to get it elsewhere, which will be schema.version.json).

Closes #62.

.projenrc.ts

@@ -3,6 +3,8 @@ import { JsonPatch, cdk } from 'projen';
 import { Stability } from 'projen/lib/cdk';
 import { TrailingComma } from 'projen/lib/javascript';
 
+const SCHEMA_VERSION: typeof import('./schema/version.json') = require('./schema/version.json');
+
 export const project = new cdk.JsiiProject({
   author: 'Amazon Web Services',
   authorAddress: '',
@@ -55,7 +57,8 @@ export const project = new cdk.JsiiProject({
       printWidth: 100,
     },
   },
-  nextVersionCommand: 'tsx ./projenrc/next-version.ts',
+  // This forces every release to be the major version from the data file
+  minMajorVersion: SCHEMA_VERSION.revision,
   eslintOptions: {
     prettier: true,
     dirs: ['lib'],

lib/manifest.ts

@@ -22,7 +22,7 @@ import INTEG_SCHEMA = require('../schema/integ.schema.json');
 /**
  * Version is shared for both manifests
  */
-const SCHEMA_VERSION = require('../package.json').version;
+import SCHEMA_VERSION = require('../schema/version.json');
 
 /**
  * Options for the loadManifest operation
@@ -138,7 +138,7 @@ export class Manifest {
    * Fetch the current schema version number.
    */
   public static version(): string {
-    return SCHEMA_VERSION;
+    return `${SCHEMA_VERSION.revision}.0.0`;
   }
 
   /**

projenrc/update.ts

@@ -1,10 +1,13 @@
 import { SCHEMAS } from './schema-definition';
 import { generateSchema } from './update-schema';
+import { maybeBumpVersion } from './versioning';
 
 function update() {
+  const schemas: Record<string, any> = {};
   for (const s of SCHEMAS) {
-    generateSchema(s);
+    schemas[s] = generateSchema(s);
   }
+  maybeBumpVersion(schemas);
 }
 
 update();

projenrc/versioning.ts

@@ -0,0 +1,44 @@
+import * as crypto from 'crypto';
+import * as fs from 'fs';
+import * as path from 'path';
+import { SCHEMA_DIR } from './schema-definition';
+
+export function maybeBumpVersion(schemas: Record<string, any>) {
+  const serializedSchema = JSON.stringify(sortJson(schemas), null, 2);
+
+  const versionFile = path.join(SCHEMA_DIR, 'version.json');
+  let current: SchemaVersionFile = JSON.parse(fs.readFileSync(versionFile, 'utf8'));
+  const schemaHash = sha256(serializedSchema);
+
+  if (current.schemaHash !== schemaHash) {
+    current = { schemaHash, revision: current.revision + 1 };
+    console.log(`Schemas changed, bumping version to ${current.revision}`);
+  }
+
+  fs.writeFileSync(versionFile, JSON.stringify(current, null, 2));
+}
+
+function sha256(x: string) {
+  const hash = crypto.createHash('sha256');
+  hash.update(x);
+  return hash.digest('hex');
+}
+
+interface SchemaVersionFile {
+  revision: number;
+  schemaHash: string;
+}
+
+function sortJson<A>(x: A): A {
+  if (Array.isArray(x)) {
+    return x;
+  }
+  if (typeof x === 'object' && x !== null) {
+    const ret: Record<string, any> = {};
+    for (const key of Object.keys(x).sort()) {
+      ret[key] = sortJson((x as any)[key]);
+    }
+    return ret as any;
+  }
+  return x;
+}

schema/version.json

@@ -0,0 +1,4 @@
+{
+  "schemaHash": "f0ccc3212331af8a1c75830878d218fd667e5957063831be3b5bfd803b25f0cc",
+  "revision": 39
+}