chore: Add a lint step for field name constants (#32769)

We have a small linter NodeJS script that checks if any field name
constants are defined incorrectly. This PR adds this linter to the build
script, so it'll be run in CI.

app/server/build.sh

@@ -34,6 +34,7 @@ if [[ -f .env ]]; then
   source .env
 fi
 
+node scripts/check-field-constants.mjs
 
 # Build the code. $@ accepts all the parameters from the input command line and uses it in the maven build command
 mvn clean package "$@"

app/server/scripts/check-field-constants.mjs

@@ -1,7 +1,13 @@
+/**
+ * This script checks if the field constants in the Java files are named and defined correctly.
+ */
+
 import {promises as fs} from "fs";
 import path from "path";
 
 async function findInnerClassDefinitions(directory) {
+  let isPass = true;
+
   try {
     const files = await fs.readdir(directory);
 
@@ -10,29 +16,37 @@ async function findInnerClassDefinitions(directory) {
       const stats = await fs.stat(filePath);
 
       if (stats.isDirectory()) {
-        await findInnerClassDefinitions(filePath);
+        if (!await findInnerClassDefinitions(filePath)) {
-      } else if (path.extname(filePath) === '.java') {
+          isPass = false;
-        await processJavaFile(filePath);
+        }
+      } else if (path.extname(filePath) === ".java") {
+        if (!await processJavaFile(filePath)) {
+          isPass = false;
+        }
       }
     }
   } catch (err) {
     console.error(err);
+    isPass = false;
   }
+
+  return isPass;
 }
 
 async function processJavaFile(filePath) {
+  let isPass = true;
+
   try {
-    const contents = await fs.readFile(filePath, 'utf8');
+    const contents = await fs.readFile(filePath, "utf8");
 
     const innerClassRegex = /^ {4}([\w ]+?)\s+class\s+Fields\s+(extends (\w+)\.Fields)?\s*{(.+?\n {4})?}$/gsm;
 
     for (const innerClassMatch of contents.matchAll(innerClassRegex)) {
       const classQualifiers = innerClassMatch[1]; // we don't care much about this
       const expectedParentClass = innerClassMatch[3];
-      console.log(filePath, classQualifiers, expectedParentClass);
 
       for (const match of innerClassMatch[0].matchAll(/\bpublic\s+static\s+final\s+String\s+(\w+)\s+=\s+(.+?);/gs)) {
-        const key = match[1]
+        const key = match[1];
         const valMatcherParts = [`^dotted\\(`];
         for (const [i, field] of key.split("_").entries()) {
           if (i > 0) {
@@ -41,12 +55,14 @@ async function processJavaFile(filePath) {
           valMatcherParts.push(`(\\w+\\.\\w+\\.)?${field}`);
         }
         valMatcherParts.push(`\\s*\\)$`);
-        const valMatcher = new RegExp(valMatcherParts.join(''));
+        const valMatcher = new RegExp(valMatcherParts.join(""));
         if (!valMatcher.test(match[2])) {
-          console.log("key is", key);
+          console.log(filePath, classQualifiers, expectedParentClass);
-          console.log("val is", match[2]);
+          console.log("\tkey is", key);
-          console.log("pattern", valMatcher);
+          console.log("\tval is", match[2]);
-          console.error(`Field ${key} in ${filePath} is not looking right.`);
+          console.log("\tpattern", valMatcher);
+          console.error(`\tField ${key} in ${filePath} is not looking right.`);
+          isPass = false;
         }
       }
     }
@@ -58,8 +74,23 @@ async function processJavaFile(filePath) {
 
   } catch (err) {
     console.error(err);
-  }
+    isPass = false;
   }
 
-const directoryPath = '.';
+  return isPass;
-findInnerClassDefinitions(directoryPath);
+}
+
+// Can't use `import.meta.dirname` because it's not available in Node.js 18.
+// And v18 is what is included in GitHub Actions today.
+// See <https://github.com/actions/runner-images/blob/main/images/ubuntu/Ubuntu2204-Readme.md#language-and-runtime>.
+const directoryPath = import.meta.resolve("..").replace("file://", "");
+
+findInnerClassDefinitions(directoryPath)
+  .then(isPass => {
+    if (isPass) {
+      console.log("All okay.");
+    } else {
+      console.error("Some field constants are not looking good.");
+      process.exitCode = 1;
+    }
+  });