Bundle both cjs and esm for api package (#129)

* output both esm and cjs

* changeset

.changeset/weak-crabs-sniff.md

@@ -0,0 +1,5 @@
+---
+'@gitbook/api': minor
+---
+
+Output both esm and cjs for @gitbook/api

packages/api/build.sh

@@ -29,7 +29,9 @@ swagger-typescript-api --path ./spec/openapi.yaml --output ./src/ --name client.
 swagger-cli bundle ./spec/openapi.yaml --outfile ./spec/openapi.json --type json
 
 # Then we build the JS files
-echo "Bundling library from code..."
+echo "Bundling CJS format from code..."
+esbuild ./src/index.ts --bundle --platform=node --format=cjs --outfile=./dist/index.cjs --log-level=warning
+echo "Bundling ESM format from code..."
 esbuild ./src/index.ts --bundle --platform=node --format=esm --outfile=./dist/index.js --log-level=warning
 
 # Finally we build the TypeScript declaration files

packages/api/package.json

@@ -1,8 +1,9 @@
 {
     "name": "@gitbook/api",
     "type": "module",
-    "main": "dist/index.js",
-    "types": "dist/index.d.ts",
+    "main": "./dist/index.cjs",
+    "module": "./dist/index.js",
+    "types": "./dist/index.d.ts",
     "version": "0.2.2",
     "sideEffects": false,
     "files": [
@@ -29,5 +30,14 @@
         "build": "./build.sh",
         "lint": "eslint ./src/**/*.ts",
         "typecheck": "tsc --noEmit"
+    },
+    "exports": {
+        ".": {
+            "require": "./dist/index.cjs",
+            "import": "./dist/index.js",
+            "types": "./dist/index.d.ts"
+        },
+        "./spec/openapi.json": "./spec/openapi.json",
+        "./spec/openapi.yaml": "./spec/openapi.yaml"
     }
 }