Added basePath argument to DataPackage, Resource (#26)

* Add basepath

* Add basePath tests

* Export Datapackage class

data/dp2-tabular/data2.csv

@@ -0,0 +1,4 @@
+year,title,director
+1964,Dr. Strangelove or: How I Learned to Stop Worrying and Love the Bomb,Stanley Kubrick
+2004,"Spring, Summer, Fall, Winter... and Spring",Kim Ki-duk
+2006,Inland Empire,David Lynch

src/datapackage.js

@@ -1,4 +1,5 @@
 import _ from 'lodash'
+import path from 'path'
 
 import Resource from './resource'
 import Profiles from './profiles'
@@ -13,16 +14,19 @@ class DataPackage {
    * @param {String} [profile='base'] - Profile to validate against
    * @param {Boolean} [raiseInvalid=true] - Throw errors if validation fails
    * @param {Boolean} [remoteProfiles=false] - Use remote profiles
+   * @param {String|path} [basePath=null] - Base path for the resources. If the provided
+   * descriptor is a local path to a file, the default value is the dirname of the path.
    * @return {Promise} - Resolves in class instance or rejects with errors
    */
   constructor(descriptor, profile = 'base', raiseInvalid = true
-            , remoteProfiles = false) {
+            , remoteProfiles = false, basePath) {
     const self = this
 
     return new Promise((resolve, reject) => {
       self._profile = profile
       self._raiseInvalid = raiseInvalid
       self._remoteProfiles = remoteProfiles
+      self._basePath = basePath || self._getBasePath(descriptor)
 
       new Profiles(self._remoteProfiles).then(profilesInstance => {
         self._Profiles = profilesInstance
@@ -113,7 +117,7 @@ class DataPackage {
    */
   addResource(descriptor) {
     if (_.isObject(descriptor) && !_.isFunction(descriptor)) {
-      const newResource = new Resource(descriptor)
+      const newResource = new Resource(descriptor, this._basePath)
           , resourceFound = _.find(this.resources
                                  , resource => _.isEqual(resource, newResource))
 
@@ -123,7 +127,7 @@ class DataPackage {
         const valid = this._validateDescriptor(newDescriptor, this._profile)
         if (this._shouldRaise(valid)) throw new Array(this._errors)
         this._descriptor = newDescriptor
-        this._resources.push(new Resource(descriptor))
+        this._resources.push(new Resource(descriptor, this._basePath))
 
         return this.valid
       }
@@ -203,7 +207,7 @@ class DataPackage {
     const resources = []
 
     _.forEach(descriptor.resources, resource => {
-      resources.push(new Resource(resource))
+      resources.push(new Resource(resource, this._basePath))
     })
 
     return resources
@@ -220,6 +224,24 @@ class DataPackage {
   _shouldRaise(valid) {
     return !valid && this._raiseInvalid
   }
+
+  /**
+   * Returns the basepath from the path of the current descriptor if it is a
+   * local path.
+   *
+   * @param {String} descriptor
+   * @return {String|null}
+   * @private
+   */
+  _getBasePath(descriptor) {
+    if (typeof descriptor === 'string') {
+      if (!Utils.isRemoteURL(descriptor)) {
+        return path.dirname(descriptor)
+      }
+    }
+
+    return null
+  }
 }
 
 export default DataPackage

src/index.js

@@ -1,3 +1,4 @@
+import Datapackage from './datapackage'
 import Resource from './resource'
 import Profiles from './profiles'
 import validate from './validate'

src/resource.js

@@ -1,17 +1,19 @@
-
 import url from 'url'
 import jts from 'jsontableschema'
 import _ from 'lodash'
+import path from 'path'
 
-/**
- * Base class for all Data Package's resource types.
- *
- * @returns {Resource}
- */
+/* Base class for all Data Package's resource types. */
 export default class Resource {
-
-  constructor(descriptor) {
+  /**
+   * Create a Resource instance.
+   *
+   * @param {Object} descriptor
+   * @param {String} [basePath=null]
+   */
+  constructor(descriptor, basePath = null) {
     this._descriptor = descriptor
+    this._basePath = basePath
     this.REMOTE_PROTOCOLS = ['http:', 'https:', 'ftp:', 'ftps:']
   }
 
@@ -56,11 +58,18 @@ export default class Resource {
 
   /**
    * Returns the path where data is located or
-   * if the data is inline it returns the actual data
+   * if the data is inline it returns the actual data.
+   * If the source is a path, the basepath is prepended
+   * if provided on Resource initialization.
    *
    * @returns {String|Array|Object}
    */
   get source() {
+    if (this._sourceKey === 'path' && this._basePath) {
+      const resourcePath = this.descriptor[this._sourceKey]
+      return path.normalize(`${this._basePath}/${resourcePath}`)
+    }
+
     return this.descriptor[this._sourceKey]
   }
 

test/datapackage.js

@@ -2,6 +2,7 @@ import 'babel-polyfill'
 import fs from 'fs'
 import { assert } from 'chai'
 import _ from 'lodash'
+import parse from 'csv-parse/lib/sync'
 
 import Datapackage from '../src/datapackage'
 
@@ -142,5 +143,41 @@ describe('Datapackage', () => {
       assert(validation === false, 'Package not marked as invalid')
       assert(datapackage.errors.length > 0, 'Validation errors not added')
     })
+
+    it('provides the dirname of the descriptor as basePath to the Resource instances', async () => {
+      const datapackage = await new Datapackage('data/dp2-tabular/datapackage.json', 'tabular')
+          , newResource = {
+                            "name": "books",
+                            "format": "csv",
+                            "path": "data2.csv",
+                            "schema": {
+                              "fields": [
+                                {
+                                  "name": "year",
+                                  "type": "integer"
+                                },
+                                {
+                                  "name": "title",
+                                  "type": "string"
+                                },
+                                {
+                                  "name": "director",
+                                  "type": "string"
+                                }
+                              ]
+                            }
+                          }
+          , expectedText = fs.readFileSync('data/dp2-tabular/data2.csv', 'utf8')
+          , expectedData = parse(expectedText, { auto_parse: true })
+
+      expectedData.shift()
+      const validation = datapackage.addResource(newResource)
+          , table = await datapackage.resources[1].table
+          , data = await table.read()
+
+      assert(validation === true, 'Added resource failed to validate')
+      assert(datapackage.resources.length === 2, 'New resource not added to datapackge')
+      assert(_.isEqual(data, expectedData), 'Wrong data loaded')
+    })
   })
 })

test/resource.js

@@ -3,6 +3,7 @@ import { assert } from 'chai'
 import jts from 'jsontableschema'
 import Resource from '../src/resource'
 import _ from 'lodash'
+import path from 'path'
 
 import dp1 from '../data/dp1/datapackage.json'
 
@@ -91,6 +92,23 @@ describe('Resource', () => {
        assert(table === null, 'Returned value not null')
      })
 
+  describe('_basePath', () => {
+    it('accepts a basePath', () => {
+      const basePath = 'data/dp1'
+        , resource = new Resource(dp1.resources[0], basePath)
+        , resourceBasePath = resource.source
+
+      assert(path.dirname(resourceBasePath) === path.normalize(basePath), 'Incorrect base path')
+    })
+
+    it('_basePath is `null` if basePath argument is not provided', () => {
+      const resource = new Resource({})
+        , source = resource._basePath
+
+      assert(source === null, 'basePath not `null`')
+    })
+  })
+
   describe('Tests with dp1 from data', () => {
     let dpResources = []