Adding basic file browsing support

registry/src/s3.ts

@@ -5,6 +5,18 @@ if (!config.s3) {
    throw new Error("Config is missing [s3] section!");
 }
 
+if (!config.s3.endpoint) {
+   throw new Error("Config is missing s3.endpoint!");
+}
+
+if (!config.s3.accessKey) {
+   throw new Error("Config is missing s3.accessKey!");
+}
+
+if (!config.s3.secretKey) {
+   throw new Error("Config is missing s3.secretKey!");
+}
+
 const bucket = new S3.S3Bucket({
    bucket: config.s3.bucket || "deno-registry",
    endpointURL: config.s3.endpoint,