From 06ef0e3615c434456436230ad388225ee2524684 Mon Sep 17 00:00:00 2001
From: Braydon Fuller <courier@braydon.com>
Date: Mon, 15 Apr 2019 15:56:05 -0700
Subject: [PATCH] indexer: simplify addrindex query

---
 lib/indexer/addrindexer.js | 83 +++++++++++---------------------------
 test/indexer-test.js       |  8 ++--
 2 files changed, 27 insertions(+), 64 deletions(-)

diff --git a/lib/indexer/addrindexer.js b/lib/indexer/addrindexer.js
index 7b91a420..b6112226 100644
--- a/lib/indexer/addrindexer.js
+++ b/lib/indexer/addrindexer.js
@@ -186,10 +186,14 @@ class AddrIndexer extends Indexer {
   }
 
   /**
-   * Get all transaction hashes to an address.
+   * Get transaction hashes to an address in ascending or descending
+   * order. If the `after` argument is supplied, results will be given
+   * _after_ that transaction hash. The default order is ascending from
+   * oldest to latest.
    * @param {Address} addr
    * @param {Object} options
-   * @param {Boolean} options.limit
+   * @param {Buffer} options.after - A transaction hash
+   * @param {Number} options.limit
    * @param {Boolean} options.reverse
    * @returns {Promise} - Returns {@link Hash}[].
    */
@@ -197,7 +201,7 @@ class AddrIndexer extends Indexer {
   async getHashesByAddress(addr, options = {}) {
     const txs = [];
 
-    const {reverse} = options;
+    const {after, reverse} = options;
     let {limit} = options;
 
     if (!limit)
@@ -209,59 +213,6 @@ class AddrIndexer extends Indexer {
     const hash = Address.getHash(addr);
     const prefix = addr.getPrefix();
 
-    await this.db.keys({
-      gte: layout.A.min(prefix, hash),
-      lte: layout.A.max(prefix, hash),
-      limit,
-      reverse,
-      parse: (key) => {
-        const [,, height, index] = layout.A.decode(key);
-        txs.push([height, index]);
-      }
-    });
-
-    const hashes = [];
-
-    for (const [height, index] of txs)
-      hashes.push(await this.db.get(layout.C.encode(height, index)));
-
-    return hashes;
-  }
-
-  /**
-   * Get all transaction hashes to an address after
-   * a specific txid.
-   * @param {Address} addr
-   * @param {Object} options
-   * @param {Buffer} options.txid
-   * @param {Boolean} options.limit
-   * @param {Boolean} options.reverse
-   * @returns {Promise} - Returns {@link Hash}[].
-   */
-
-  async getHashesByAddressAfter(addr, options = {}) {
-    const txs = [];
-
-    const hash = Address.getHash(addr);
-    const prefix = addr.getPrefix();
-
-    const {txid, reverse} = options;
-    let {limit} = options;
-
-    if (!limit)
-      limit = this.maxTxs;
-
-    if (limit > this.maxTxs)
-      throw new Error('Limit above max of ${this.maxTxs}.');
-
-    const raw = await this.db.get(layout.c.encode(txid));
-
-    if (!raw)
-      return [];
-
-    const count = Count.fromRaw(raw);
-    const {height, index} = count;
-
     const opts = {
       limit,
       reverse,
@@ -271,12 +222,24 @@ class AddrIndexer extends Indexer {
       }
     };
 
-    if (!reverse) {
-      opts.gt = layout.A.min(prefix, hash, height, index);
-      opts.lte = layout.A.max(prefix, hash);
+    if (after) {
+      const raw = await this.db.get(layout.c.encode(after));
+      if (!raw)
+        return [];
+
+      const count = Count.fromRaw(raw);
+      const {height, index} = count;
+
+      if (!reverse) {
+        opts.gt = layout.A.min(prefix, hash, height, index);
+        opts.lte = layout.A.max(prefix, hash);
+      } else {
+        opts.gte = layout.A.min(prefix, hash);
+        opts.lt = layout.A.max(prefix, hash, height, index);
+      }
     } else {
       opts.gte = layout.A.min(prefix, hash);
-      opts.lt = layout.A.max(prefix, hash, height, index);
+      opts.lte = layout.A.max(prefix, hash);
     }
 
     await this.db.keys(opts);
diff --git a/test/indexer-test.js b/test/indexer-test.js
index 839bc3cd..86b9cb9f 100644
--- a/test/indexer-test.js
+++ b/test/indexer-test.js
@@ -129,8 +129,8 @@ describe('Indexer', function() {
 
       const txid = hashes[4];
 
-      const next = await addrindexer.getHashesByAddressAfter(
-        addr, {txid: txid, limit: 5});
+      const next = await addrindexer.getHashesByAddress(
+        addr, {after: txid, limit: 5});
 
       assert.strictEqual(next.length, 5);
 
@@ -149,8 +149,8 @@ describe('Indexer', function() {
 
       const txid = hashes[4];
 
-      const next = await addrindexer.getHashesByAddressAfter(
-        addr, {txid: txid, limit: 5, reverse: true});
+      const next = await addrindexer.getHashesByAddress(
+        addr, {after: txid, limit: 5, reverse: true});
 
       assert.strictEqual(next.length, 5);