feat: add files/flush (#643)

* add flush

* add test and readme

README.md

@@ -169,6 +169,7 @@ $ ipfs config --json API.HTTPHeaders.Access-Control-Allow-Methods "[\"PUT\", \"P
   - [`ipfs.files.get(hash, [callback])`](https://github.com/ipfs/interface-ipfs-core/tree/master/SPEC/FILES.md#get)
     - alias to `ipfs.get`
   - `ipfs.ls`
+  - `ipfs.files.flush(path, [callback])`
   - mfs (mutable file system) specific:
     - `ipfs.files.cp`
     - `ipfs.files.ls`

src/files/flush.js

@@ -0,0 +1,12 @@
+'use strict'
+
+const promisify = require('promisify-es6')
+
+module.exports = (send) => {
+  return promisify((args, callback) => {
+    return send({
+      path: 'files/flush',
+      args: args
+    }, callback)
+  })
+}

src/files/index.js

@@ -15,6 +15,7 @@ module.exports = (arg) => {
     get: require('./get')(send),
     getReadableStream: require('./get-readable-stream')(send),
     getPullStream: require('./get-pull-stream')(send),
+    flush: require('./flush')(send),
 
     // Specific to MFS (for now)
     cp: require('./cp')(send),

test/files.spec.js

@@ -200,6 +200,10 @@ describe('.files (the MFS API part)', function () {
       ipfs.files.mkdir('/test-folder', done)
     })
 
+    it('files.flush', (done) => {
+      ipfs.files.flush('/', done)
+    })
+
     it('files.cp', (done) => {
       ipfs.files.cp([
         '/ipfs/Qma4hjFTnCasJ8PVp3mZbZK5g2vGDT4LByLJ7m8ciyRFZP',