[WIP] feat: add errors with codes and utils

package.json

@@ -94,6 +94,7 @@
     "err-code": "^1.1.2",
     "file-type": "^10.2.0",
     "fnv1a": "^1.0.1",
+    "format-util": "^1.0.3",
     "fsm-event": "^2.1.0",
     "get-folder-size": "^2.0.0",
     "glob": "^7.1.3",

src/core/errors.js

@@ -0,0 +1,91 @@
+'use strict'
+
+const format = require('format-util')
+const assert = require('assert')
+
+const messages = new Map()
+const { defineProperty } = Object
+
+/**
+ * Get formatted message for a error code
+ *
+ * @see https://nodejs.org/api/util.html#util_util_format_format_args
+ * @param {string} key - Error code
+ * @param {Array} args - Placeholder values for the message
+ * @returns {string} - Formatted message
+ */
+function getMessage (key, args) {
+  const msg = messages.get(key)
+
+  if (typeof msg === 'function') {
+    assert(
+      msg.length <= args.length, // Default options do not count.
+      `Code: ${key}; The provided arguments length (${args.length}) does not ` +
+        `match the required ones (${msg.length}).`
+    )
+    return msg.apply(null, args)
+  }
+
+  const expectedLength = (msg.match(/%[dfijoOs]/g) || []).length
+  assert(
+    expectedLength === args.length,
+    `Code: ${key}; The provided arguments length (${args.length}) does not ` +
+      `match the required ones (${expectedLength}).`
+  )
+  if (args.length === 0) { return msg }
+
+  args.unshift(msg)
+  return format.apply(null, args)
+}
+
+function makeError (Base, key) {
+  return class IPFSError extends Base {
+    /**
+     * Creates an instance of IPFSError.
+     * @param {...Any} args - Message placeholders values
+     */
+    constructor (...args) {
+      super(getMessage(key, args))
+    }
+
+    get name () {
+      return `${super.name} [${key}]`
+    }
+
+    set name (value) {
+      defineProperty(this, 'name', {
+        configurable: true,
+        enumerable: true,
+        value,
+        writable: true
+      })
+    }
+
+    get code () {
+      return key
+    }
+
+    set code (value) {
+      defineProperty(this, 'code', {
+        configurable: true,
+        enumerable: true,
+        value,
+        writable: true
+      })
+    }
+  }
+}
+
+function E (sym, val, def) {
+  messages.set(sym, val)
+  const c = makeError(def, sym)
+  c.code = sym
+  return c
+}
+
+// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error#Error_types
+module.exports = {
+  ERR_IPFS_MISSING_IPLD_FORMAT: E('ERR_IPFS_MISSING_IPLD_FORMAT', 'Missing IPLD format %s', Error),
+  ERR_IPFS_PRELOAD_ABORTED: E('ERR_IPFS_PRELOAD_ABORTED', 'Preload aborted for %s', Error),
+  ERR_IPFS_INVALID_PATH: E('ERR_IPFS_INVALID_PATH', 'Invalid IPFS path: %s', TypeError)
+}

src/core/index.js

@@ -18,6 +18,7 @@ const EventEmitter = require('events')
 const config = require('./config')
 const boot = require('./boot')
 const components = require('./components')
+const { ERR_IPFS_MISSING_IPLD_FORMAT } = require('./errors')
 
 // replaced by repo-browser when running in the browser
 const defaultRepo = require('./runtime/repo-nodejs')
@@ -120,8 +121,12 @@ class IPFS extends EventEmitter {
       blockService: this._blockService,
       loadFormat: (codec, callback) => {
         this.log('Loading IPLD format', codec)
-        if (IpldFormats[codec]) return callback(null, IpldFormats[codec])
-        callback(new Error(`Missing IPLD format "${codec}"`))
+
+        if (IpldFormats[codec]) {
+          return callback(null, IpldFormats[codec])
+        }
+
+        callback(new ERR_IPFS_MISSING_IPLD_FORMAT(codec))
       }
     })
     this._preload = preload(this)

src/core/preload.js

@@ -6,6 +6,7 @@ const toUri = require('multiaddr-to-uri')
 const debug = require('debug')
 const CID = require('cids')
 const preload = require('./runtime/preload-nodejs')
+const { ERR_IPFS_PRELOAD_ABORTED } = require('./errors')
 
 const log = debug('jsipfs:preload')
 log.error = debug('jsipfs:preload:error')
@@ -48,7 +49,7 @@ module.exports = self => {
     const now = Date.now()
 
     retry({ times: fallbackApiUris.length }, (cb) => {
-      if (stopped) return cb(new Error(`preload aborted for ${cid}`))
+      if (stopped) return cb(new ERR_IPFS_PRELOAD_ABORTED(cid))
 
       // Remove failed request from a previous attempt
       requests = requests.filter(r => r !== request)

src/core/utils.js

@@ -4,8 +4,8 @@ const promisify = require('promisify-es6')
 const map = require('async/map')
 const isIpfs = require('is-ipfs')
 const CID = require('cids')
+const { ERR_IPFS_INVALID_PATH } = require('./errors')
 
-const ERR_BAD_PATH = 'ERR_BAD_PATH'
 exports.OFFLINE_ERROR = 'This command must be run in online mode. Try running \'ipfs daemon\' first.'
 
 /**
@@ -21,11 +21,10 @@ exports.OFFLINE_ERROR = 'This command must be run in online mode. Try running \'
  * @throws on an invalid @param ipfsPath
  */
 function parseIpfsPath (ipfsPath) {
-  const invalidPathErr = new Error('invalid ipfs ref path')
   ipfsPath = ipfsPath.replace(/^\/ipfs\//, '')
   const matched = ipfsPath.match(/([^/]+(?:\/[^/]+)*)\/?$/)
   if (!matched) {
-    throw invalidPathErr
+    throw new ERR_IPFS_INVALID_PATH(ipfsPath)
   }
 
   const [hash, ...links] = matched[1].split('/')
@@ -34,7 +33,7 @@ function parseIpfsPath (ipfsPath) {
   if (isIpfs.cid(hash)) {
     return { hash, links }
   } else {
-    throw invalidPathErr
+    throw new ERR_IPFS_INVALID_PATH(ipfsPath)
   }
 }
 
@@ -57,7 +56,7 @@ const normalizePath = (pathStr) => {
   } else if (isIpfs.path(pathStr)) {
     return pathStr
   } else {
-    throw Object.assign(new Error(`invalid ${pathStr} path`), { code: ERR_BAD_PATH })
+    throw new ERR_IPFS_INVALID_PATH(pathStr)
   }
 }