CNS-334: Remove duration parameter from Plans

Plans are always for 1 month.
The `tx subscription buy` message indicates duration (in months).

proto/plans/plan.proto

@@ -8,16 +8,15 @@ import "cosmos/base/v1beta1/coin.proto";
 
 message Plan {
     string index = 1;
-    uint64 duration = 2; // duration of the plan's subscription in months
-    uint64 block = 3; // the epoch that this plan was created
-    cosmos.base.v1beta1.Coin price = 4 [(gogoproto.nullable) = false]; // plan price (in ulava)
-    uint64 compute_units = 5; // max CU for the whole plan duration
-    uint64 compute_units_per_epoch = 6; // max CU per epoch for the whole plan duration
-    uint64 servicers_to_pair = 7; // max providers to be paired in an epoch
-    bool allow_overuse = 8; // allow CU overuse flag
-    uint64 overuse_rate = 9; // price of CU overuse
-    string name = 10; // plan name (non-unique "human" name)
-    string description = 11; // plan description (for humans)
-    string type = 12; // plan type
-    uint64 annual_discount_percentage = 13; // discount for buying the plan for a year
-}
+    uint64 block = 2; // the epoch that this plan was created
+    cosmos.base.v1beta1.Coin price = 3 [(gogoproto.nullable) = false]; // plan price (in ulava)
+    uint64 compute_units = 4; // max CU for the whole plan duration
+    uint64 compute_units_per_epoch = 5; // max CU per epoch for the whole plan duration
+    uint64 servicers_to_pair = 6; // max providers to be paired in an epoch
+    bool allow_overuse = 7; // allow CU overuse flag
+    uint64 overuse_rate = 8; // price of CU overuse
+    string name = 9; // plan name (non-unique "human" name)
+    string description = 10; // plan description (for humans)
+    string type = 11; // plan type
+    uint64 annual_discount_percentage = 12; // discount for buying the plan for a year
+}

testutil/common/common.go

@@ -45,7 +45,6 @@ func CreateMockPlan() plantypes.Plan {
 		Name:                     "mock plan",
 		Description:              "plan for testing",
 		Type:                     "rpc",
-		Duration:                 200,
 		Block:                    100,
 		Price:                    sdk.NewCoin("ulava", sdk.NewInt(100)),
 		ComputeUnits:             1000,

x/plans/keeper/plan_test.go

@@ -63,7 +63,6 @@ func CreateTestPlans(planAmount uint64, withSameIndex bool, startIndex uint64) [
 			Name:                     "test plan",
 			Description:              "plan to test",
 			Type:                     "rpc",
-			Duration:                 200,
 			Block:                    100,
 			Price:                    sdk.NewCoin("ulava", sdk.OneInt()),
 			ComputeUnits:             1000,
@@ -154,14 +153,13 @@ func TestUpdatePlanInSameEpoch(t *testing.T) {
 }
 
 const (
-	DURATION_FIELD    = 1
-	PRICE_FIELD       = 2
-	OVERUSE_FIELDS    = 3
-	CU_FIELD          = 4
-	SERVICERS_FIELD   = 5
-	NAME_FIELD        = 6
-	DESCRIPTION_FIELD = 7
-	TYPE_FIELD        = 8
+	PRICE_FIELD = iota+1
+	OVERUSE_FIELDS
+	CU_FIELD
+	SERVICERS_FIELD
+	NAME_FIELD
+	DESCRIPTION_FIELD
+	TYPE_FIELD
 )
 
 // Test that the plan verification before adding it to the plan storage is working correctly
@@ -178,14 +176,13 @@ func TestInvalidPlanAddition(t *testing.T) {
 		name       string
 		fieldIndex int
 	}{
-		{"InvalidDurationTest", 1},
-		{"InvalidPriceTest", 2},
-		{"InvalidOveruseTest", 3},
-		{"InvalidCuTest", 4},
-		{"InvalidServicersToPairTest", 5},
-		{"InvalidNameTest", 6},
-		{"InvalidDescriptionTest", 7},
-		{"InvalidTypeTest", 8},
+		{"InvalidPriceTest", 1},
+		{"InvalidOveruseTest", 2},
+		{"InvalidCuTest", 3},
+		{"InvalidServicersToPairTest", 4},
+		{"InvalidNameTest", 5},
+		{"InvalidDescriptionTest", 6},
+		{"InvalidTypeTest", 7},
 	}
 
 	for _, tt := range tests {
@@ -195,8 +192,6 @@ func TestInvalidPlanAddition(t *testing.T) {
 
 			// each test, change one field to an invalid value
 			switch tt.fieldIndex {
-			case DURATION_FIELD:
-				planToTest[0].Duration = 0
 			case PRICE_FIELD:
 				planToTest[0].Price = sdk.NewCoin(epochstoragetypes.TokenDenom, sdk.ZeroInt())
 			case OVERUSE_FIELDS:

x/plans/types/errors.go

@@ -9,7 +9,6 @@ import (
 // x/plan module sentinel errors
 var (
 	ErrEmptyPlans                 = sdkerrors.Register(ModuleName, 1, "plans list is empty")
-	ErrInvalidPlanDuration        = sdkerrors.Register(ModuleName, 2, "plan's duration field is invalid")
 	ErrInvalidPlanPrice           = sdkerrors.Register(ModuleName, 3, "plan's price field is invalid")
 	ErrInvalidPlanOveruse         = sdkerrors.Register(ModuleName, 4, "plan's CU overuse fields are invalid")
 	ErrInvalidPlanServicersToPair = sdkerrors.Register(ModuleName, 5, "plan's servicersToPair field is invalid")

x/plans/types/plan.go

@@ -8,11 +8,6 @@ import (
 
 // Function to validate a plan object fields
 func (p Plan) ValidatePlan() error {
-	// check that the plan's duration is non-zero
-	if p.GetDuration() == 0 {
-		return sdkerrors.Wrap(ErrInvalidPlanDuration, "plan's duration can't be zero")
-	}
-
 	// check that the plan's price is non-zero
 	if p.GetPrice().IsEqual(sdk.NewCoin(epochstoragetypes.TokenDenom, sdk.ZeroInt())) {
 		return sdkerrors.Wrap(ErrInvalidPlanPrice, "plan's price can't be zero")