refactor(streams): Refactor response stream handling. (#465)

Author: haadcode

package.json

@@ -23,7 +23,6 @@
   },
   "dependencies": {
     "async": "^2.1.4",
-    "bl": "^1.1.2",
     "bs58": "^4.0.0",
     "concat-stream": "^1.6.0",
     "detect-node": "^2.0.3",
@@ -43,6 +42,7 @@
     "peer-id": "^0.8.1",
     "peer-info": "^0.8.1",
     "promisify-es6": "^1.0.2",
+    "pump": "^1.0.2",
     "qs": "^6.3.0",
     "readable-stream": "1.1.14",
     "stream-http": "^2.5.0",

src/api/add.js

@@ -1,24 +1,26 @@
 'use strict'
 
 const isStream = require('isstream')
-const addToDagNodesTransform = require('../add-to-dagnode-transform')
 const promisify = require('promisify-es6')
+const DAGNodeStream = require('../dagnode-stream')
 
 module.exports = (send) => {
   return promisify((files, callback) => {
-    const good = Buffer.isBuffer(files) ||
+    const ok = Buffer.isBuffer(files) ||
                isStream.isReadable(files) ||
                Array.isArray(files)
 
-    if (!good) {
-      callback(new Error('"files" must be a buffer, readable stream, or array of objects'))
+    if (!ok) {
+      return callback(new Error('"files" must be a buffer, readable stream, or array of objects'))
     }
 
-    const sendWithTransform = send.withTransform(addToDagNodesTransform)
-
-    return sendWithTransform({
+    const request = {
       path: 'add',
       files: files
-    }, callback)
+    }
+
+    // Transform the response stream to DAGNode values
+    const transform = (res, callback) => DAGNodeStream.streamToValue(send, res, callback)
+    send.andTransform(request, transform, callback)
   })
 }

src/api/block.js

@@ -1,10 +1,10 @@
 'use strict'
 
 const promisify = require('promisify-es6')
-const bl = require('bl')
 const Block = require('ipfs-block')
 const multihash = require('multihashes')
 const CID = require('cids')
+const streamToValue = require('../stream-to-value')
 
 module.exports = (send) => {
   return {
@@ -21,25 +21,27 @@ module.exports = (send) => {
         opts = {}
       }
 
-      return send({
-        path: 'block/get',
-        args: args,
-        qs: opts
-      }, (err, res) => {
-        if (err) {
-          return callback(err)
-        }
+      // Transform the response from Buffer or a Stream to a Block
+      const transform = (res, callback) => {
         if (Buffer.isBuffer(res)) {
           callback(null, new Block(res))
         } else {
-          res.pipe(bl((err, data) => {
+          streamToValue(res, (err, data) => {
             if (err) {
               return callback(err)
             }
             callback(null, new Block(data))
-          }))
+          })
         }
-      })
+      }
+
+      const request = {
+        path: 'block/get',
+        args: args,
+        qs: opts
+      }
+
+      send.andTransform(request, transform, callback)
     }),
     stat: promisify((args, opts, callback) => {
       // TODO this needs to be adjusted with the new go-ipfs http-api
@@ -51,19 +53,22 @@ module.exports = (send) => {
         callback = opts
         opts = {}
       }
-      return send({
+
+      const request = {
         path: 'block/stat',
         args: args,
         qs: opts
-      }, (err, stats) => {
-        if (err) {
-          return callback(err)
-        }
+      }
+
+      // Transform the response from { Key, Size } objects to { key, size } objects
+      const transform = (stats, callback) => {
         callback(null, {
           key: stats.Key,
           size: stats.Size
         })
-      })
+      }
+
+      send.andTransform(request, transform, callback)
     }),
     put: promisify((block, cid, callback) => {
       // TODO this needs to be adjusted with the new go-ipfs http-api
@@ -81,15 +86,15 @@ module.exports = (send) => {
         block = block.data
       }
 
-      return send({
+      const request = {
         path: 'block/put',
         files: block
-      }, (err, blockInfo) => {
-        if (err) {
-          return callback(err)
-        }
-        callback(null, new Block(block))
-      })
+      }
+
+      // Transform the response to a Block
+      const transform = (blockInfo, callback) => callback(null, new Block(block))
+
+      send.andTransform(request, transform, callback)
     })
   }
 }

src/api/dht.js

@@ -1,6 +1,7 @@
 'use strict'
 
 const promisify = require('promisify-es6')
+const streamToValue = require('../stream-to-value')
 
 module.exports = (send) => {
   return {
@@ -19,11 +20,13 @@ module.exports = (send) => {
         opts = {}
       }
 
-      send({
+      const request = {
         path: 'dht/findprovs',
         args: args,
         qs: opts
-      }, callback)
+      }
+
+      send.andTransform(request, streamToValue, callback)
     }),
     get: promisify((key, opts, callback) => {
       if (typeof opts === 'function' &&

src/api/get.js

@@ -1,11 +1,11 @@
 'use strict'
 
-const tarStreamToObjects = require('../tar-stream-to-objects')
-const cleanMultihash = require('../clean-multihash')
 const promisify = require('promisify-es6')
+const cleanMultihash = require('../clean-multihash')
+const TarStreamToObjects = require('../tar-stream-to-objects')
 
 module.exports = (send) => {
-  return promisify(function get (path, opts, callback) {
+  return promisify((path, opts, callback) => {
     if (typeof opts === 'function' &&
         !callback) {
       callback = opts
@@ -26,12 +26,13 @@ module.exports = (send) => {
       return callback(err)
     }
 
-    var sendWithTransform = send.withTransform(tarStreamToObjects)
-
-    sendWithTransform({
+    const request = {
       path: 'get',
       args: path,
       qs: opts
-    }, callback)
+    }
+
+    // Convert the response stream to TarStream objects
+    send.andTransform(request, TarStreamToObjects, callback)
   })
 }

src/api/log.js

@@ -1,5 +1,6 @@
 'use strict'
 
+const pump = require('pump')
 const ndjson = require('ndjson')
 const promisify = require('promisify-es6')
 
@@ -12,7 +13,8 @@ module.exports = (send) => {
         if (err) {
           return callback(err)
         }
-        callback(null, response.pipe(ndjson.parse()))
+        const outputStream = pump(response, ndjson.parse())
+        callback(null, outputStream)
       })
     })
   }

src/api/object.js

@@ -5,7 +5,7 @@ const DAGNode = dagPB.DAGNode
 const DAGLink = dagPB.DAGLink
 const promisify = require('promisify-es6')
 const bs58 = require('bs58')
-const bl = require('bl')
+const streamToValue = require('../stream-to-value')
 const cleanMultihash = require('../clean-multihash')
 const LRU = require('lru-cache')
 const lruOptions = {
@@ -188,7 +188,7 @@ module.exports = (send) => {
         }
 
         if (typeof result.pipe === 'function') {
-          result.pipe(bl(callback))
+          streamToValue(result, callback)
         } else {
           callback(null, result)
         }

src/api/ping.js

@@ -1,18 +1,36 @@
 'use strict'
 
 const promisify = require('promisify-es6')
+const streamToValue = require('../stream-to-value')
 
 module.exports = (send) => {
   return promisify((id, callback) => {
-    send({
+    const request = {
       path: 'ping',
       args: id,
       qs: { n: 1 }
-    }, function (err, res) {
-      if (err) {
-        return callback(err, null)
-      }
-      callback(null, res[1])
-    })
+    }
+
+    // Transform the response stream to a value:
+    // { Success: <boolean>, Time: <number>, Text: <string> }
+    const transform = (res, callback) => {
+      streamToValue(res, (err, res) => {
+        if (err) {
+          return callback(err)
+        }
+
+        // go-ipfs http api currently returns 3 lines for a ping.
+        // they're a little messed, so take the correct values from each lines.
+        const pingResult = {
+          Success: res[1].Success,
+          Time: res[1].Time,
+          Text: res[2].Text
+        }
+
+        callback(null, pingResult)
+      })
+    }
+
+    send.andTransform(request, transform, callback)
   })
 }

src/api/refs.js

@@ -1,28 +1,36 @@
 'use strict'
 
 const promisify = require('promisify-es6')
+const streamToValue = require('../stream-to-value')
 
 module.exports = (send) => {
   const refs = promisify((args, opts, callback) => {
     if (typeof (opts) === 'function') {
       callback = opts
       opts = {}
     }
-    return send({
+
+    const request = {
       path: 'refs',
       args: args,
       qs: opts
-    }, callback)
+    }
+
+    send.andTransform(request, streamToValue, callback)
   })
+
   refs.local = promisify((opts, callback) => {
     if (typeof (opts) === 'function') {
       callback = opts
       opts = {}
     }
-    return send({
+
+    const request = {
       path: 'refs',
       qs: opts
-    }, callback)
+    }
+
+    send.andTransform(request, streamToValue, callback)
   })
 
   return refs

src/api/util/fs-add.js

@@ -1,8 +1,8 @@
 'use strict'
 
 const isNode = require('detect-node')
-const addToDagNodesTransform = require('./../../add-to-dagnode-transform')
 const promisify = require('promisify-es6')
+const DAGNodeStream = require('../../dagnode-stream')
 
 module.exports = (send) => {
   return promisify((path, opts, callback) => {
@@ -28,12 +28,14 @@ module.exports = (send) => {
       return callback(new Error('"path" must be a string'))
     }
 
-    const sendWithTransform = send.withTransform(addToDagNodesTransform)
-
-    sendWithTransform({
+    const request = {
       path: 'add',
       qs: opts,
       files: path
-    }, callback)
+    }
+
+    // Transform the response stream to DAGNode values
+    const transform = (res, callback) => DAGNodeStream.streamToValue(send, res, callback)
+    send.andTransform(request, transform, callback)
   })
 }