From 149845fc5326623cfc63aa109a62182450e4c9b5 Mon Sep 17 00:00:00 2001
From: Evan Hahn <me@evanhahn.com>
Date: Thu, 12 Sep 2024 13:30:58 -0500
Subject: [PATCH] chore: work around Ajv module bug in generated code (#256)

JavaScript module inconsistency strikes again.

In some cases, Ajv will inject `require` calls into generated code even
if you ask it to generate ESM. [This is a bug][0].

For example, here's something it adds if you use [the string `minLength`
or `maxLength` properties][1]:

    // ...
    const func2 = require("ajv/dist/runtime/ucs2length").default;
    // ...

That won't work in an ESM environment.

As a workaround, I inject the following into our generated code:

    import { createRequire } from 'node:module';
    const require = createRequire(import.meta.url);

This, along with moving `ajv` to production dependencies, should work
around this issue until the bug is fixed.

[0]: https://github.com/ajv-validator/ajv/issues/2209
[1]: https://json-schema.org/understanding-json-schema/reference/string#length
---
 package-lock.json                   | 13 ++++---------
 package.json                        |  2 +-
 scripts/lib/generate-validations.js | 10 +++++++++-
 3 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/package-lock.json b/package-lock.json
index 52958165..a2a6ebdc 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -9,6 +9,7 @@
       "version": "3.0.0-next.26",
       "license": "MIT",
       "dependencies": {
+        "ajv": "^8.12.0",
         "compact-encoding": "^2.12.0",
         "protobufjs": "^7.2.5",
         "type-fest": "^4.26.0"
@@ -18,7 +19,6 @@
         "@json-schema-tools/dereferencer": "^1.6.3",
         "@types/compact-encoding": "^2.15.0",
         "@types/json-schema": "^7.0.12",
-        "ajv": "^8.12.0",
         "c8": "^8.0.1",
         "cpy-cli": "^5.0.0",
         "eslint": "^8.46.0",
@@ -833,7 +833,7 @@
       "version": "8.12.0",
       "resolved": "https://registry.npmjs.org/ajv/-/ajv-8.12.0.tgz",
       "integrity": "sha512-sRu1kpcO9yLtYxBKvqfTeh9KzZEwO3STyX1HT+4CaDzC6HpTGYhIhPIzj9XuKU7KYDwnaeh5hcOwjy1QuJzBPA==",
-      "dev": true,
+      "license": "MIT",
       "dependencies": {
         "fast-deep-equal": "^3.1.1",
         "json-schema-traverse": "^1.0.0",
@@ -1819,8 +1819,7 @@
     "node_modules/fast-deep-equal": {
       "version": "3.1.3",
       "resolved": "https://registry.npmjs.org/fast-deep-equal/-/fast-deep-equal-3.1.3.tgz",
-      "integrity": "sha512-f3qQ9oQy9j2AhBe/H9VC91wLmKBCCU/gDOnKNAYG5hswO7BLKj09Hc5HYNz9cGI++xlpDCIgDaitVs03ATR84Q==",
-      "dev": true
+      "integrity": "sha512-f3qQ9oQy9j2AhBe/H9VC91wLmKBCCU/gDOnKNAYG5hswO7BLKj09Hc5HYNz9cGI++xlpDCIgDaitVs03ATR84Q=="
     },
     "node_modules/fast-fifo": {
       "version": "1.1.0",
@@ -2885,8 +2884,7 @@
     "node_modules/json-schema-traverse": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/json-schema-traverse/-/json-schema-traverse-1.0.0.tgz",
-      "integrity": "sha512-NM8/P9n3XjXhIZn1lLhkFaACTOURQXjWhV4BA/RnOv8xvgqtqpAX9IO4mRQxSx1Rlo4tqzeqb0sOlruaOy3dug==",
-      "dev": true
+      "integrity": "sha512-NM8/P9n3XjXhIZn1lLhkFaACTOURQXjWhV4BA/RnOv8xvgqtqpAX9IO4mRQxSx1Rlo4tqzeqb0sOlruaOy3dug=="
     },
     "node_modules/json-stable-stringify-without-jsonify": {
       "version": "1.0.1",
@@ -3944,7 +3942,6 @@
       "version": "2.1.1",
       "resolved": "https://registry.npmjs.org/punycode/-/punycode-2.1.1.tgz",
       "integrity": "sha512-XRsRjdf+j5ml+y/6GKHPZbrF/8p2Yga0JPtdqTIY2Xe5ohJPD9saDJJLPvp9+NSBprVvevdXZybnj2cv8OEd0A==",
-      "dev": true,
       "engines": {
         "node": ">=6"
       }
@@ -4332,7 +4329,6 @@
       "version": "2.0.2",
       "resolved": "https://registry.npmjs.org/require-from-string/-/require-from-string-2.0.2.tgz",
       "integrity": "sha512-Xf0nWe6RseziFMu+Ap9biiUbmplq6S9/p+7w7YXP/JBHhrUDDUhwa+vANyubuqfZWTveU//DYVGsDG7RKL/vEw==",
-      "dev": true,
       "engines": {
         "node": ">=0.10.0"
       }
@@ -5129,7 +5125,6 @@
       "version": "4.4.1",
       "resolved": "https://registry.npmjs.org/uri-js/-/uri-js-4.4.1.tgz",
       "integrity": "sha512-7rKUyy33Q1yc98pQ1DAmLtwX109F7TIfWlW1Ydo8Wl1ii1SeHieeh0HHfPeL2fMXK6z0s8ecKs9frCuLJvndBg==",
-      "dev": true,
       "dependencies": {
         "punycode": "^2.1.0"
       }
diff --git a/package.json b/package.json
index 8abf8b6e..707b4440 100644
--- a/package.json
+++ b/package.json
@@ -42,7 +42,6 @@
     "@json-schema-tools/dereferencer": "^1.6.3",
     "@types/compact-encoding": "^2.15.0",
     "@types/json-schema": "^7.0.12",
-    "ajv": "^8.12.0",
     "c8": "^8.0.1",
     "cpy-cli": "^5.0.0",
     "eslint": "^8.46.0",
@@ -61,6 +60,7 @@
     "typescript": "^5.5.4"
   },
   "dependencies": {
+    "ajv": "^8.12.0",
     "compact-encoding": "^2.12.0",
     "protobufjs": "^7.2.5",
     "type-fest": "^4.26.0"
diff --git a/scripts/lib/generate-validations.js b/scripts/lib/generate-validations.js
index 09bef59c..f8cf93bb 100644
--- a/scripts/lib/generate-validations.js
+++ b/scripts/lib/generate-validations.js
@@ -26,5 +26,13 @@ export function generateValidations(config, jsonSchemas) {
   ajv.addKeyword('meta:enum')
 
   // generate validation code
-  return '// @ts-nocheck\n' + standaloneCode(ajv, schemaExports)
+  return [
+    '// @ts-nocheck',
+    // AJV has [a bug when generating ESM code][0]: it includes `require` in the
+    // output. We should be able to remove this once the bug is fixed.
+    // [0]: https://github.com/ajv-validator/ajv/issues/2209
+    "import { createRequire } from 'node:module';",
+    'const require = createRequire(import.meta.url);',
+    standaloneCode(ajv, schemaExports),
+  ].join('\n')
 }