Updated offers setup to allow trial values

refs https://github.com/TryGhost/Team/issues/1726

- updates offer setup to allow new `trial` as discount type, was prev only `fixed` and `percent`
- updates offer setup to allow `amount` as free trial days value
- updates offer setup to allow `trial` as discount duration value for trial offers, was prev only `once`/`forever`/`repeating`

ghost/offers/lib/application/OfferMapper.js

@@ -11,7 +11,7 @@
  * @prop {string} display_title
  * @prop {string} display_description
  *
- * @prop {'percent'|'fixed'} type
+ * @prop {'percent'|'fixed'|'trial'} type
  *
  * @prop {'month'|'year'} cadence
  * @prop {number} amount
@@ -19,7 +19,7 @@
  * @prop {boolean} currency_restriction
  * @prop {string} currency
  *
- * @prop {'once'|'repeating'|'forever'} duration
+ * @prop {'once'|'repeating'|'forever'|'trial'} duration
  * @prop {null|number} duration_in_months
  *
  * @prop {'active'|'archived'} status

ghost/offers/lib/application/OfferRepository.js

@@ -108,7 +108,7 @@ class OfferRepository {
             code: json.code,
             display_title: json.portal_title,
             display_description: json.portal_description,
-            type: json.discount_type === 'amount' ? 'fixed' : 'percent',
+            type: json.discount_type === 'amount' ? 'fixed' : json.discount_type,
             amount: json.discount_amount,
             cadence: json.interval,
             currency: json.currency,
@@ -192,7 +192,7 @@ class OfferRepository {
             code: offer.code.value,
             portal_title: offer.displayTitle.value || null,
             portal_description: offer.displayDescription.value || null,
-            discount_type: offer.type.value === 'fixed' ? 'amount' : 'percent',
+            discount_type: offer.type.value === 'fixed' ? 'amount' : offer.type.value,
             discount_amount: offer.amount.value,
             interval: offer.cadence.value,
             product_id: offer.tier.id,

ghost/offers/lib/domain/models/Offer.js

@@ -276,10 +276,19 @@ class Offer {
             });
         }
 
+        //CASE: For offer type trial, the duration can only be `trial`
+        if (type.value === 'trial' && duration.value.type !== 'trial') {
+            throw new errors.InvalidOfferDuration({
+                message: 'Offer `duration` must be "trial" for offer type "trial".'
+            });
+        }
+
         let currency = null;
         let amount;
         if (type.equals(OfferType.Percentage)) {
             amount = OfferAmount.OfferPercentageAmount.create(data.amount);
+        } else if (type.equals(OfferType.Trial)) {
+            amount = OfferAmount.OfferTrialAmount.create(data.amount);
         } else if (type.equals(OfferType.Fixed)) {
             amount = OfferAmount.OfferFixedAmount.create(data.amount);
             currency = OfferCurrency.create(data.currency);

ghost/offers/lib/domain/models/OfferAmount.js

@@ -52,6 +52,31 @@ class OfferFixedAmount extends OfferAmount {
     static InvalidOfferAmount = InvalidOfferAmount;
 }
 
+class OfferTrialAmount extends OfferAmount {
+    /** @param {unknown} amount */
+    static create(amount) {
+        if (typeof amount !== 'number') {
+            throw new InvalidOfferAmount({
+                message: 'Offer `amount` must be an integer greater than 0.'
+            });
+        }
+        if (!Number.isInteger(amount)) {
+            throw new InvalidOfferAmount({
+                message: 'Offer `amount` must be a integer greater than 0.'
+            });
+        }
+        if (amount < 0) {
+            throw new InvalidOfferAmount({
+                message: 'Offer `amount` must be a integer greater than 0.'
+            });
+        }
+        return new OfferTrialAmount(amount);
+    }
+
+    static InvalidOfferAmount = InvalidOfferAmount;
+}
+
 module.exports = OfferAmount;
 module.exports.OfferPercentageAmount = OfferPercentageAmount;
 module.exports.OfferFixedAmount = OfferFixedAmount;
+module.exports.OfferTrialAmount = OfferTrialAmount;

ghost/offers/lib/domain/models/OfferDuration.js

@@ -3,7 +3,7 @@ const InvalidOfferDuration = require('../errors').InvalidOfferDuration;
 
 /**
  * @typedef {object} BasicDuration
- * @prop {'once'|'forever'} type
+ * @prop {'once'|'forever'|'trial'} type
  */
 
 /**
@@ -26,9 +26,9 @@ class OfferDuration extends ValueObject {
                 message: 'Offer `duration` must be a string.'
             });
         }
-        if (type !== 'once' && type !== 'repeating' && type !== 'forever') {
+        if (type !== 'once' && type !== 'repeating' && type !== 'forever' && type !== 'trial') {
             throw new InvalidOfferDuration({
-                message: 'Offer `duration` must be one of "once", "repeating" or "forever".'
+                message: 'Offer `duration` must be one of "once", "repeating", "forever" or "trial.'
             });
         }
         if (type !== 'repeating') {

ghost/offers/lib/domain/models/OfferType.js

@@ -1,7 +1,7 @@
 const ValueObject = require('./shared/ValueObject');
 const InvalidOfferType = require('../errors').InvalidOfferType;
 
-/** @extends ValueObject<'fixed'|'percent'> */
+/** @extends ValueObject<'fixed'|'percent'|'trial'> */
 class OfferType extends ValueObject {
     /** @param {unknown} type */
     static create(type) {
@@ -10,9 +10,9 @@ class OfferType extends ValueObject {
                 message: 'Offer `type` must be a string.'
             });
         }
-        if (type !== 'percent' && type !== 'fixed') {
+        if (type !== 'percent' && type !== 'fixed' && type !== 'trial') {
             throw new InvalidOfferType({
-                message: 'Offer `type` must be one of "percent" or "fixed".'
+                message: 'Offer `type` must be one of "percent", "fixed" or "trial".'
             });
         }
 
@@ -24,6 +24,8 @@ class OfferType extends ValueObject {
     static Percentage = new OfferType('percent');
 
     static Fixed = new OfferType('fixed');
+
+    static Trial = new OfferType('trial');
 }
 
 module.exports = OfferType;

ghost/offers/test/lib/domain/models/Offer.test.js

@@ -41,6 +41,48 @@ describe('Offer', function () {
             );
         });
 
+        it('Creates a valid instance of a trial Offer', async function () {
+            const offer = await Offer.create({
+                name: 'My Trial Offer',
+                code: 'offer-code-trial',
+                display_title: 'My Offer Title',
+                display_description: 'My Offer Description',
+                cadence: 'month',
+                type: 'trial',
+                amount: 10,
+                duration: 'trial',
+                currency: 'USD',
+                tier: {
+                    id: ObjectID()
+                }
+            }, mockUniqueChecker);
+            should.ok(
+                offer instanceof Offer,
+                'Offer.create should return an instance of Offer'
+            );
+        });
+
+        it('Throws an error if the duration for trial offer is not right', async function () {
+            await Offer.create({
+                name: 'My Trial Offer',
+                code: 'trial-test',
+                display_title: 'My Offer Title',
+                display_description: 'My Offer Description',
+                cadence: 'month',
+                type: 'trial',
+                amount: 10,
+                duration: 'forever',
+                currency: 'USD',
+                tier: {
+                    id: ObjectID()
+                }
+            }, mockUniqueChecker).then(() => {
+                should.fail('Expected an error');
+            }, (err) => {
+                should.ok(err);
+            });
+        });
+
         it('Throws an error if the code is not unique', async function () {
             await Offer.create({
                 name: 'My Offer',
@@ -150,6 +192,27 @@ describe('Offer', function () {
             should.equal(offer.currency, null);
         });
 
+        it('Has a currency of null if the type is trial', async function () {
+            const data = {
+                name: 'My Trial Offer',
+                code: 'offer-code-trial',
+                display_title: 'My Offer Title',
+                display_description: 'My Offer Description',
+                cadence: 'year',
+                type: 'trial',
+                amount: 20,
+                duration: 'trial',
+                currency: 'USD',
+                tier: {
+                    id: ObjectID()
+                }
+            };
+
+            const offer = await Offer.create(data, mockUniqueChecker);
+
+            should.equal(offer.currency, null);
+        });
+
         it('Can handle ObjectID, string and no id', async function () {
             const data = {
                 name: 'My Offer',

ghost/offers/test/lib/domain/models/OfferAmount.test.js

@@ -1,4 +1,4 @@
-const {OfferPercentageAmount, OfferFixedAmount} = require('../../../../lib/domain/models/OfferAmount');
+const {OfferPercentageAmount, OfferFixedAmount, OfferTrialAmount} = require('../../../../lib/domain/models/OfferAmount');
 
 describe('OfferAmount', function () {
     describe('OfferPercentageAmount', function () {
@@ -118,4 +118,58 @@ describe('OfferAmount', function () {
             should.ok(typeof cadence.value === 'number');
         });
     });
+
+    describe('OfferTrialAmount', function () {
+        describe('OfferTrialAmount.create factory', function () {
+            it('Will only create an OfferTrialAmount containing an integer greater than 0', function () {
+                try {
+                    OfferTrialAmount.create();
+                    should.fail();
+                } catch (err) {
+                    should.ok(
+                        err instanceof OfferTrialAmount.InvalidOfferAmount,
+                        'expected an InvalidOfferAmount error'
+                    );
+                }
+
+                try {
+                    OfferTrialAmount.create('1');
+                    should.fail();
+                } catch (err) {
+                    should.ok(
+                        err instanceof OfferTrialAmount.InvalidOfferAmount,
+                        'expected an InvalidOfferAmount error'
+                    );
+                }
+
+                try {
+                    OfferTrialAmount.create(-1);
+                    should.fail();
+                } catch (err) {
+                    should.ok(
+                        err instanceof OfferTrialAmount.InvalidOfferAmount,
+                        'expected an InvalidOfferAmount error'
+                    );
+                }
+
+                try {
+                    OfferTrialAmount.create(3.14);
+                    should.fail();
+                } catch (err) {
+                    should.ok(
+                        err instanceof OfferTrialAmount.InvalidOfferAmount,
+                        'expected an InvalidOfferAmount error'
+                    );
+                }
+
+                OfferTrialAmount.create(200);
+            });
+        });
+
+        it('Exposes a number on the value property', function () {
+            const cadence = OfferTrialAmount.create(42);
+
+            should.ok(typeof cadence.value === 'number');
+        });
+    });
 });

ghost/offers/test/lib/domain/models/OfferDuration.test.js

@@ -5,6 +5,7 @@ describe('OfferDuration', function () {
         it('Will only allow creating a once, repeating or forever duration', function () {
             OfferDuration.create('once');
             OfferDuration.create('forever');
+            OfferDuration.create('trial');
             OfferDuration.create('repeating', 2);
 
             try {

ghost/offers/test/lib/domain/models/OfferType.test.js

@@ -5,6 +5,7 @@ describe('OfferType', function () {
         it('Creates an Offer type containing either "fixed" or "percent"', function () {
             OfferType.create('fixed');
             OfferType.create('percent');
+            OfferType.create('trial');
 
             try {
                 OfferType.create('other');
@@ -41,4 +42,11 @@ describe('OfferType', function () {
             should.ok(OfferType.Fixed.equals(OfferType.create('fixed')));
         });
     });
+
+    describe('OfferType.Trial', function () {
+        it('Is an OfferType with a value of "trial"', function () {
+            should.equal(OfferType.Trial.value, 'trial');
+            should.ok(OfferType.Trial.equals(OfferType.create('trial')));
+        });
+    });
 });