[android] Trust android local CA store for self signed certificates

plugins/network_security_config.xml

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="utf-8"?>
+<network-security-config>
+    <base-config cleartextTrafficPermitted="false">
+        <trust-anchors>
+            <certificates src="system" />
+            <certificates src="user" />
+        </trust-anchors>
+    </base-config>
+</network-security-config>

plugins/withTrustLocalCerts.js

@@ -0,0 +1,44 @@
+const { AndroidConfig, withAndroidManifest } = require("@expo/config-plugins");
+const { Paths } = require("@expo/config-plugins/build/android");
+const path = require("path");
+const fs = require("fs");
+const fsPromises = fs.promises;
+
+const { getMainApplicationOrThrow } = AndroidConfig.Manifest;
+
+const withTrustLocalCerts = (config) => {
+  return withAndroidManifest(config, async (config) => {
+    config.modResults = await setCustomConfigAsync(config, config.modResults);
+    return config;
+  });
+};
+
+async function setCustomConfigAsync(config, androidManifest) {
+  const src_file_path = path.join(__dirname, "network_security_config.xml");
+  const res_file_path = path.join(
+    await Paths.getResourceFolderAsync(config.modRequest.projectRoot),
+    "xml",
+    "network_security_config.xml"
+  );
+
+  const res_dir = path.resolve(res_file_path, "..");
+
+  if (!fs.existsSync(res_dir)) {
+    await fsPromises.mkdir(res_dir);
+  }
+
+  try {
+    await fsPromises.copyFile(src_file_path, res_file_path);
+  } catch (e) {
+    throw new Error(
+      `Failed to copy network security config file from ${src_file_path} to ${res_file_path}: ${e.message}`
+    );
+  }
+  const mainApplication = getMainApplicationOrThrow(androidManifest);
+  mainApplication.$["android:networkSecurityConfig"] =
+    "@xml/network_security_config";
+
+  return androidManifest;
+}
+
+module.exports = withTrustLocalCerts;