From 508eb692e3197dc495c5cb9f3e56272e563d79fe Mon Sep 17 00:00:00 2001
From: Derrick Hammer <derrick@derrickhammer.com>
Date: Thu, 18 Aug 2022 16:35:40 -0400
Subject: [PATCH] *First steps in breaking resolver framework to be modular

---
 package.json            |  5 +--
 src/common.ts           |  8 ++---
 src/index.ts            | 60 ++++++++++++++++++++++++---------
 src/resolverRegistry.ts | 74 +++++++++++++++++++++++++++++++++++++++++
 4 files changed, 125 insertions(+), 22 deletions(-)
 create mode 100644 src/resolverRegistry.ts

diff --git a/package.json b/package.json
index 5fbbe27..3a3ae37 100644
--- a/package.json
+++ b/package.json
@@ -52,7 +52,7 @@
 		"@lumeweb/kernel-dht-client": "https://github.com/LumeWeb/kernel-dht-client.git",
 		"@lumeweb/kernel-rpc-client": "https://github.com/LumeWeb/kernel-rpc-client.git",
 		"@lumeweb/kernel-utils": "https://github.com/LumeWeb/kernel-utils.git",
-		"@lumeweb/resolver": "https://github.com/LumeWeb/resolver.git#hypercore",
+		"@lumeweb/resolver-common": "github:LumeWeb/resolver-common",
 		"libkmodule": "^0.2.11",
 		"randombytes": "https://github.com/LumeWeb/randombytes-browser.git",
 		"randomfill": "https://github.com/LumeWeb/randomfill.git"
@@ -63,6 +63,7 @@
 		"os": "os-browserify",
 		"stream": "os-browserify",
 		"libskynetnode": false,
-		"js-sha3": "@lumeweb/js-sha3-browser"
+		"js-sha3": "@lumeweb/js-sha3-browser",
+		"@lumeweb/dht-rpc-client": false
 	}
 }
diff --git a/src/common.ts b/src/common.ts
index a3f9fc5..382b323 100644
--- a/src/common.ts
+++ b/src/common.ts
@@ -1,6 +1,6 @@
-import resolvers from "@lumeweb/resolver"
-import { RpcNetwork } from "@lumeweb/kernel-rpc-client"
+import { RpcNetwork } from "@lumeweb/kernel-rpc-client";
+import { ResolverRegistry } from "./resolverRegistry.js";
 
-const network = new RpcNetwork()
+const network: RpcNetwork = new RpcNetwork();
 
-export const resolver = resolvers.createDefaultResolver(network as any)
+export const resolver = new ResolverRegistry(network as any);
diff --git a/src/index.ts b/src/index.ts
index 2b486c0..bbd8f39 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,24 +1,52 @@
-import {addHandler, handleMessage} from "libkmodule"
-import type {ActiveQuery} from "libkmodule"
-import {resolver} from "./common.js"
+import { addHandler, handleMessage } from "libkmodule";
+import type { ActiveQuery } from "libkmodule";
+import { resolver } from "./common.js";
 
-import {relayReady, setupRelayListSubscription} from "./relays.js"
+import { relayReady, setupRelayListSubscription } from "./relays.js";
+import { validSkylink } from "libskynet/dist/skylinkvalidate.js";
+import { ResolverModule } from "./resolverRegistry.js";
+import { b64ToBuf } from "libskynet";
 
-setupRelayListSubscription()
+setupRelayListSubscription();
 
-addHandler("resolve", resolveHandler)
-onmessage = handleMessage
+addHandler("resolve", handleResolve);
+addHandler("register", handleRegister);
+addHandler("clear", handleClear);
+addHandler("getResolvers", handleGetResolvers);
+onmessage = handleMessage;
 
-async function resolveHandler(aq: ActiveQuery) {
-    const query = aq.callerInput
+async function handleResolve(aq: ActiveQuery) {
+  const query = aq.callerInput;
+  if (!("domain" in query)) {
+    aq.reject("domain required");
+    return;
+  }
 
-    if (!("domain" in query)) {
-        aq.reject("domain required")
-        return
-    }
-
-    await relayReady();
-    aq.respond(await resolver.resolve(aq.callerInput.domain, aq.callerInput.params ?? {}, aq.callerInput.force || false))
+  await relayReady();
+  aq.respond(
+    await resolver.resolve(
+      aq.callerInput.domain,
+      aq.callerInput.options ?? {},
+      aq.callerInput.bypassCache || false
+    )
+  );
 }
 
+async function handleRegister(aq: ActiveQuery) {
+  if (!validSkylink(b64ToBuf(aq.domain).shift() as Uint8Array)) {
+    aq.reject("invalid skylink");
+    return;
+  }
 
+  resolver.register(new ResolverModule(resolver, aq.domain));
+  aq.respond();
+}
+
+async function handleClear(aq: ActiveQuery) {
+  resolver.clear();
+  aq.respond();
+}
+
+async function handleGetResolvers(aq: ActiveQuery) {
+  aq.respond([...resolver.resolvers.values()]);
+}
diff --git a/src/resolverRegistry.ts b/src/resolverRegistry.ts
new file mode 100644
index 0000000..10590b2
--- /dev/null
+++ b/src/resolverRegistry.ts
@@ -0,0 +1,74 @@
+import {
+  DNSResult,
+  ResolverOptions,
+  DNS_RECORD_TYPE,
+  resolverError,
+} from "@lumeweb/resolver-common";
+import type { RpcNetwork } from "@lumeweb/kernel-rpc-client";
+import { callModule } from "libkmodule/dist";
+
+export class ResolverRegistry {
+  private _resolvers: Set<ResolverModule> = new Set();
+  private _rpcNetwork: RpcNetwork;
+
+  constructor(network: RpcNetwork) {
+    this._rpcNetwork = network;
+  }
+
+  get resolvers(): Set<ResolverModule> {
+    return this._resolvers;
+  }
+
+  get rpcNetwork(): RpcNetwork {
+    return this._rpcNetwork;
+  }
+
+  public async resolve(
+    domain: string,
+    options: ResolverOptions = { type: DNS_RECORD_TYPE.DEFAULT },
+    bypassCache: boolean = false
+  ): Promise<DNSResult> {
+    for (const resolver of this._resolvers) {
+      const result = await resolver.resolve(domain, options, bypassCache);
+      if (!result.error && result.records.length) {
+        return result;
+      }
+    }
+
+    return { records: [] };
+  }
+
+  public register(resolver: ResolverModule): void {
+    this._resolvers.add(resolver);
+  }
+
+  public clear(): void {
+    this._resolvers.clear();
+  }
+}
+
+export class ResolverModule {
+  private resolver: ResolverRegistry;
+  private domain: string;
+
+  constructor(resolver: ResolverRegistry, domain: string) {
+    this.resolver = resolver;
+  }
+
+  async resolve(
+    domain: string,
+    options: ResolverOptions,
+    bypassCache: boolean
+  ): Promise<DNSResult> {
+    const [ret, err] = await callModule(this.domain, "resolve", {
+      domain,
+      options,
+      bypassCache,
+    });
+    if (err) {
+      return resolverError(err);
+    }
+
+    return ret;
+  }
+}