feat: make PAYLOAD_CONFIG_PATH optional (#2839)

* feat: make PAYLOAD_CONFIG_PATH optional

* hardcode common search paths

* docs: update docs regarding PAYLOAD_CONFIG_PATH

* make the tsConfig parser less prone to errors

src/config/find.ts

@@ -1,6 +1,43 @@
 import path from 'path';
 import findUp from 'find-up';
+import fs from 'fs';
 
+/**
+* Returns the source and output paths from the nearest tsconfig.json file.
+* If no tsconfig.json file is found, returns the current working directory.
+* @returns An object containing the source and output paths.
+*/
+const getTSConfigPaths = (): { srcPath: string, outPath: string } => {
+  const tsConfigPath = findUp.sync('tsconfig.json');
+
+  if (!tsConfigPath) {
+    return { srcPath: process.cwd(), outPath: process.cwd() };
+  }
+
+  try {
+    // Read the file as a string and remove trailing commas
+    const rawTsConfig = fs.readFileSync(tsConfigPath, 'utf-8')
+      .replace(/,\s*]/g, ']')
+      .replace(/,\s*}/g, '}');
+
+    const tsConfig = JSON.parse(rawTsConfig);
+
+    const srcPath = tsConfig.compilerOptions?.rootDir || process.cwd();
+    const outPath = tsConfig.compilerOptions?.outDir || process.cwd();
+
+    return { srcPath, outPath };
+  } catch (error) {
+    console.error(`Error parsing tsconfig.json: ${error}`); // Do not throw the error, as we can still continue with the other config path finding methods
+    return { srcPath: process.cwd(), outPath: process.cwd() };
+  }
+};
+
+
+/**
+ * Searches for a Payload configuration file.
+ * @returns The absolute path to the Payload configuration file.
+ * @throws An error if no configuration file is found.
+ */
 const findConfig = (): string => {
   // If the developer has specified a config path,
   // format it if relative and use it directly if absolute
@@ -12,21 +49,46 @@ const findConfig = (): string => {
     return path.resolve(process.cwd(), process.env.PAYLOAD_CONFIG_PATH);
   }
 
-  const configPath = findUp.sync((dir) => {
-    const tsPath = path.join(dir, 'payload.config.ts');
-    const hasTS = findUp.sync.exists(tsPath);
+  const { srcPath, outPath } = getTSConfigPaths();
 
-    if (hasTS) return tsPath;
+  const searchPaths = process.env.NODE_ENV === 'production' ? [outPath, srcPath] : [srcPath];
 
-    const jsPath = path.join(dir, 'payload.config.js');
-    const hasJS = findUp.sync.exists(jsPath);
+  // eslint-disable-next-line no-restricted-syntax
+  for (const searchPath of searchPaths) {
+    const configPath = findUp.sync((dir) => {
+      const tsPath = path.join(dir, 'payload.config.ts');
+      const hasTS = findUp.sync.exists(tsPath);
 
-    if (hasJS) return jsPath;
+      if (hasTS) {
+        return tsPath;
+      }
 
-    return undefined;
-  });
+      const jsPath = path.join(dir, 'payload.config.js');
+      const hasJS = findUp.sync.exists(jsPath);
 
-  if (configPath) return configPath;
+      if (hasJS) {
+        return jsPath;
+      }
+
+      return undefined;
+    }, { cwd: searchPath });
+
+    if (configPath) {
+      return configPath;
+    }
+  }
+
+  // If no config file is found in the directories defined by tsconfig.json,
+  // try searching in the 'src' and 'dist' directory as a last resort, as they are most commonly used
+  if (process.env.NODE_ENV === 'production') {
+    const distConfigPath = findUp.sync(['payload.config.js', 'payload.config.ts'], { cwd: path.resolve(process.cwd(), 'dist') });
+
+    if (distConfigPath) return distConfigPath;
+  } else {
+    const srcConfigPath = findUp.sync(['payload.config.js', 'payload.config.ts'], { cwd: path.resolve(process.cwd(), 'src') });
+
+    if (srcConfigPath) return srcConfigPath;
+  }
 
   throw new Error('Error: cannot find Payload config. Please create a configuration file located at the root of your current working directory called "payload.config.js" or "payload.config.ts".');
 };