feat: .getMany

Author: daviddias

src/index.js

@@ -1,5 +1,7 @@
 'use strict'
 
+const asyncMap = require('async/map')
+
 /**
  * BlockService is a hybrid block datastore. It stores data in a local
  * datastore and may retrieve data from a remote Exchange.
@@ -94,6 +96,24 @@ class BlockService {
     return this._repo.blocks.get(cid, callback)
   }
 
+  /**
+   * Get multiple blocks a block by cid.
+   *
+   * @param {CID} cid
+   * @param {function(Error, Block)} callback
+   * @returns {void}
+   */
+  getMany (cids, callback) {
+    if (!Array.isArray(cids)) {
+      return callback(new Error('first arg must be an array of cids'))
+    }
+    if (this.hasExchange()) {
+      return this._bitswap.getMany(cids, callback)
+    }
+
+    asyncMap(cids, (cid, cb) => this._repo.blocks.get(cid, cb), callback)
+  }
+
   /**
    * Delete a block from the blockstore.
    *

test/block-service-test.js

@@ -55,6 +55,7 @@ module.exports = (repo) => {
 
       it('store many blocks', (done) => {
         const data = [Buffer.from('1'), Buffer.from('2'), Buffer.from('3')]
+
         map(data, (d, cb) => {
           multihashing(d, 'sha2-256', (err, hash) => {
             expect(err).to.not.exist()
@@ -66,8 +67,9 @@ module.exports = (repo) => {
         })
       })
 
-      it('get many blocks', (done) => {
+      it('get many blocks through get', (done) => {
         const data = [Buffer.from('1'), Buffer.from('2'), Buffer.from('3')]
+
         waterfall([
           (cb) => map(data, (d, cb) => {
             multihashing(d, 'sha2-256', (err, hash) => {
@@ -87,6 +89,27 @@ module.exports = (repo) => {
         ], done)
       })
 
+      it('get many blocks through getMany', (done) => {
+        const data = [Buffer.from('1'), Buffer.from('2'), Buffer.from('3')]
+
+        waterfall([
+          (cb) => map(data, (d, cb) => {
+            multihashing(d, 'sha2-256', (err, hash) => {
+              expect(err).to.not.exist()
+              cb(null, new Block(d, new CID(hash)))
+            })
+          }, cb),
+          (blocks, cb) => map(blocks, (b, cb) => cb(null, b.cid), (err, cids) => {
+            expect(err).to.not.exist()
+            bs.getMany(cids, (err, _blocks) => {
+              expect(err).to.not.exist()
+              expect(blocks).to.eql(blocks)
+              cb()
+            })
+          })
+        ], done)
+      })
+
       it('delete a block', (done) => {
         const data = Buffer.from('Will not live that much')
         multihashing(data, 'sha2-256', (err, hash) => {