Merge pull request #158 from schemepunk/filter-values

feat(transform): offer array and object value filtering

__tests__/plugins/transform/filterValues.js

@@ -0,0 +1,78 @@
+'use strict';
+
+const FilterValues = require('../../../lib/plugins/transform/filterValues');
+
+class BaseXform {
+  constructor(options) {
+    this.options = options;
+  }
+
+  async transform(value) { // eslint-disable-line class-methods-use-this
+    return value;
+  }
+
+  async getHoldOvers() {
+    return Promise.resolve(this.holdOvers);
+  }
+}
+const filterValues = new (FilterValues(BaseXform))();
+
+let value;
+let value2;
+
+describe('Delimit Values tests', () => {
+  beforeEach(() => {
+    filterValues.options = {
+      filterItems: [
+        2,
+        4
+      ],
+    };
+    // Test case value.
+    value = {
+      attribute1: 1,
+      attribute2: 2,
+      attribute3: 3,
+      attribute4: 4
+    };
+    value2 = [1, 2, 3, 4];
+  });
+
+  test('Filter out.', async () => {
+    filterValues.options.filterBias = 'out';
+    expect(await filterValues.transform(value)).toEqual({
+      attribute1: 1,
+      attribute3: 3
+    });
+  });
+  test('Filter in.', async () => {
+    filterValues.options.filterBias = 'in';
+    expect(await filterValues.transform(value)).toEqual({
+      attribute2: 2,
+      attribute4: 4
+    });
+  });
+  test('Filter out array.', async () => {
+    filterValues.options.filterBias = 'out';
+    expect(await filterValues.transform(value2)).toEqual([
+      1,
+      3
+    ]);
+  });
+  test('Filter in array.', async () => {
+    filterValues.options.filterBias = 'in';
+    expect(await filterValues.transform(value2)).toEqual([
+      2,
+      4
+    ]);
+  });
+  test('Non array or object will throw.', async () => {
+    filterValues.options.filterBias = 'in';
+    try {
+      await filterValues.transform('this value');
+    }
+    catch (error) {
+      expect(error.message).toBe('Value must be an object or an array to filter.');
+    }
+  });
+});

lib/molotov.json

@@ -63,6 +63,13 @@
           "typeAdapter",
           "filterObjects"
         ],
+        "filterValues": [
+          "filterValues"
+        ],
+        "filterValuesMulti": [
+          "typeAdapter",
+          "filterValues"
+        ],
         "objectKeysTransform": [
           "objectKeysTransform"
         ],

lib/plugins/index.js

@@ -14,6 +14,7 @@ const appendValues = require('./transform/appendValues');
 const delimitValues = require('./transform/delimitValues');
 const filterAttributes = require('./transform/filterAttributes');
 const filterObjects = require('./transform/filterObjects');
+const filterValues = require('./transform/filterValues');
 const objectKeysTransform = require('./transform/objectKeysTransform');
 const prependValues = require('./transform/prependValues');
 const regexWordBoundariesValues = require('./transform/regexWordBoundariesValues');
@@ -40,6 +41,7 @@ const plugins = {
     delimitValues,
     filterAttributes,
     filterObjects,
+    filterValues,
     objectKeysTransform,
     prependValues,
     regexWordBoundariesValues,

lib/plugins/transform/filterAttributes.js

@@ -1,6 +1,7 @@
 'use strict';
 
 const _ = require('lodash');
+const filterByBias = require('./helpers/filterByBias');
 /**
  * This is a transformation mixin for SchemePunk.
  * SchemePunk mixins follow the formula for mixins described at:
@@ -21,13 +22,10 @@ module.exports = superclass => class extends superclass {
     // This is the bias.
     const filterBias = _.get(this, 'options.filterBias', 'out');
 
-    const tempValueKeys = _.filter(Object.keys(value), (item) => {
-      if (filterBias !== 'out') {
-        // We want to return only the filter items
-        return filterItems.indexOf(item) > -1;
-      }
-      return filterItems.indexOf(item) === -1;
-    });
+    const tempValueKeys = _.filter(
+      Object.keys(value),
+      item => filterByBias(item, filterItems, filterBias)
+    );
 
     const tempValue = _.pick(value, tempValueKeys);
     // Call super.transform and pass along the new value to honor composition.

lib/plugins/transform/filterValues.js

@@ -0,0 +1,43 @@
+'use strict';
+
+const _ = require('lodash');
+const filterByBias = require('./helpers/filterByBias');
+/**
+ * This is a transformation mixin for SchemePunk.
+ * SchemePunk mixins follow the formula for mixins described at:
+ * http://justinfagnani.com/2015/12/21/real-mixins-with-javascript-classes/
+ * More info in the README.
+ *
+ */
+module.exports = superclass => class extends superclass {
+  /**
+     * Function to transform an array or object by filtering on its values.
+     * @param value
+     *  A value to perform a transformation upon.
+     */
+  async transform(value) {
+    if (typeof value !== 'object') {
+      throw new Error(
+        'Value must be an object or an array to filter.'
+      );
+    }
+    let tempValues;
+    // These are the items we will filter out or for.
+    const filterItems = _.get(this, 'options.filterItems', []);
+    // This is the bias.
+    const filterBias = _.get(this, 'options.filterBias', 'out');
+    if (_.isArray(value)) {
+      tempValues = _.filter(value, item => filterByBias(item, filterItems, filterBias));
+    }
+    else {
+      tempValues = _.pickBy(value, (val) => {
+        if (filterBias !== 'out') {
+          return _.includes(filterItems, val);
+        }
+        return !_.includes(filterItems, val);
+      });
+    }
+
+    return super.transform(tempValues);
+  }
+};

lib/plugins/transform/helpers/filterByBias.js

@@ -0,0 +1,25 @@
+'use strict';
+
+
+/**
+ * Filters a  collection based on the value of an item
+ *
+ * @param {*} item
+ *   The value we are seeking to assert as included or excluded.
+ * @param {array<*>} items
+ *   An array of values.
+ * @param {string} filterBias
+ *   Designates whether to return true based on the inclusion or exclusion of
+ *     an itemToFilterFor within the passed items. Can be "in" or "out".
+ * @returns {boolean}
+ *   Returns true if the value meets our filter.
+ */
+function filterByBias(itemToFilterFor, items, filterBias) {
+  if (filterBias !== 'out') {
+    // We want to return only the filter items
+    return items.indexOf(itemToFilterFor) > -1;
+  }
+  return items.indexOf(itemToFilterFor) === -1;
+}
+
+module.exports = filterByBias;

package.json

@@ -1,6 +1,5 @@
 {
   "name": "@schemepunk/scheme-punk",
-  "version": "6.0.0",
   "description": "Transformation tool with pluggable sources, transformations, and destinations.",
   "scripts": {
     "commitmsg": "commitlint -e $GIT_PARAMS",
@@ -74,7 +73,6 @@
     "node": ">=8"
   },
   "readme": "ERROR: No README data found!",
-  "_id": "@schemepunk/[email protected]",
   "husky": {
     "hooks": {
       "pre-commit": "npm run lint",