Charges - Add Stub

Sometime it's make sense to make an API call without actually calling the API. In order to support that this library has a built-in stub that can be triggered. You can enable stub by injecting certain value to the context data. You can also enforce that certain API call will always return error with specific type and message.

Author: Rizal Widyarta Gowandy

.golangci.yaml

@@ -132,6 +132,9 @@ issues:
         - stylecheck
         - funlen
         - lll
+    - path: stub
+      linters:
+        - funlen
 
     # https://github.com/go-critic/go-critic/issues/926
     - linters:

README.md

@@ -79,6 +79,53 @@ func main() {
 
 For more example check [here](main_integration_test.go).
 
+## Test Double / Stub
+
+Sometime it's make sense to make an API call without actually calling the API. In order to support that this library has a built-in stub that can be triggered. You can enable stub by injecting certain value to the context data. You can also enforce that certain API call will always return error with specific type and
+message.
+
+```go
+package main
+
+import (
+	"context"
+	"log"
+
+	"github.com/benalucorp/coinbase-commerce-go"
+	"github.com/benalucorp/coinbase-commerce-go/pkg/api"
+	"github.com/benalucorp/coinbase-commerce-go/pkg/entity"
+	"github.com/benalucorp/coinbase-commerce-go/pkg/enum"
+	"github.com/benalucorp/coinbase-commerce-go/pkg/api/stub"
+)
+
+func AlwaysSuccess(ctx context.Context, client *coinbase.Client) {
+	// Enable stub that always success and return data.
+	ctx = stub.Enable(ctx)
+
+	// Call any client method.
+	resp, err := client.CreateCharge(ctx, &entity.CreateChargeReq{})
+	if err != nil {
+		log.Fatal(err)
+	}
+	log.Printf("%+v", resp)
+}
+
+func AlwaysError(ctx context.Context, client *coinbase.Client) {
+	// Enable stub that always error and return specific error.
+	ctx = stub.SetErrDetailResp(context.Background(), entity.ErrDetailResp{
+		Type:    "bad_request",
+		Message: "stub: error triggered",
+	})
+
+	// Call any client method.
+	resp, err := client.CreateCharge(ctx, &entity.CreateChargeReq{})
+	if err != nil {
+		log.Fatal(err)
+	}
+	log.Printf("%+v", resp)
+}
+```
+
 ## Supported API
 
 Version: 2018-03-22
@@ -87,4 +134,4 @@ Version: 2018-03-22
    - [Create a charge](https://commerce.coinbase.com/docs/api/#create-a-charge)
    - [Show a charge](https://commerce.coinbase.com/docs/api/#show-a-charge)
    - [List charges](https://commerce.coinbase.com/docs/api/#list-charges)
-   - [Cancel a charge](https://commerce.coinbase.com/docs/api/#cancel-a-charge)
+   - [Cancel a charge](https://commerce.coinbase.com/docs/api/#cancel-a-charge)

go.mod

@@ -5,6 +5,7 @@ go 1.14
 require (
 	github.com/go-resty/resty/v2 v2.6.0
 	github.com/kokizzu/gotro v1.817.1737
+	github.com/segmentio/ksuid v1.0.4
 	github.com/stretchr/testify v1.7.0
 	golang.org/x/net v0.0.0-20210813160813-60bc85c4be6d // indirect
 	gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b // indirect

go.sum

@@ -148,6 +148,8 @@ github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZN
 github.com/prometheus/client_model v0.0.0-20190812154241-14fe0d1b01d4/go.mod h1:xMI15A0UPsDsEKsMN9yxemIoYk6Tm2C1GtYGdfGttqA=
 github.com/rogpeppe/go-internal v1.3.0/go.mod h1:M8bDsm7K2OlrFYOpmOWEs/qY81heoFRclV5y23lUDJ4=
 github.com/ruudk/golang-pdf417 v0.0.0-20181029194003-1af4ab5afa58/go.mod h1:6lfFZQK844Gfx8o5WFuvpxWRwnSoipWe/p622j1v06w=
+github.com/segmentio/ksuid v1.0.4 h1:sBo2BdShXjmcugAMwjugoGUdUV0pcxY5mW4xKRn3v4c=
+github.com/segmentio/ksuid v1.0.4/go.mod h1:/XUiZBD3kVx5SmUOl55voK5yeAbBNNIed+2O73XgrPE=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=

main.go

@@ -2,9 +2,9 @@ package coinbase
 
 import (
 	"context"
-	"errors"
 
 	"github.com/benalucorp/coinbase-commerce-go/pkg/api"
+	"github.com/benalucorp/coinbase-commerce-go/pkg/api/stub"
 	"github.com/benalucorp/coinbase-commerce-go/pkg/entity"
 )
 
@@ -15,12 +15,15 @@ func NewClient(cfg api.Config) (*Client, error) {
 	}
 
 	return &Client{
-		charges: api.NewCharges(cfg),
+		charges:     api.NewCharges(cfg),
+		chargesStub: stub.NewCharges(),
 	}, nil
 }
 
+// Client is the main client to interact with Coinbase Commerce API.
 type Client struct {
-	charges *api.Charges
+	charges     api.ChargesItf
+	chargesStub api.ChargesItf
 }
 
 // CreateCharge charge a customer with certain amount of currency.
@@ -30,10 +33,9 @@ type Client struct {
 // to the blockchain before the charge expires.
 // Reference: https://commerce.coinbase.com/docs/api/#create-a-charge
 func (c Client) CreateCharge(ctx context.Context, req *entity.CreateChargeReq) (*entity.CreateChargeResp, error) {
-	if req == nil {
-		return nil, errors.New("payload: missing")
+	if stub.Ok(ctx) {
+		return c.chargesStub.Create(ctx, req)
 	}
-
 	return c.charges.Create(ctx, req)
 }
 
@@ -42,24 +44,21 @@ func (c Client) CreateCharge(ctx context.Context, req *entity.CreateChargeReq) (
 // This information is also returned when a charge is first created.
 // Reference: https://commerce.coinbase.com/docs/api/#show-a-charge
 func (c Client) ShowCharge(ctx context.Context, req *entity.ShowChargeReq) (*entity.ShowChargeResp, error) {
-	if req == nil {
-		return nil, errors.New("payload: missing")
-	}
-
 	if err := req.Validate(); err != nil {
 		return nil, err
 	}
-
+	if stub.Ok(ctx) {
+		return c.chargesStub.Show(ctx, req)
+	}
 	return c.charges.Show(ctx, req)
 }
 
 // ListCharges lists all the charges.
 // Reference: https://commerce.coinbase.com/docs/api/#list-charges
 func (c Client) ListCharges(ctx context.Context, req *entity.ListChargesReq) (*entity.ListChargesResp, error) {
-	if req == nil {
-		return nil, errors.New("payload: missing")
+	if stub.Ok(ctx) {
+		return c.chargesStub.List(ctx, req)
 	}
-
 	return c.charges.List(ctx, req)
 }
 
@@ -73,14 +72,12 @@ func (c Client) ListCharges(ctx context.Context, req *entity.ListChargesReq) (*e
 //
 // Reference: https://commerce.coinbase.com/docs/api/#cancel-a-charge
 func (c Client) CancelCharge(ctx context.Context, req *entity.CancelChargeReq) (*entity.CancelChargeResp, error) {
-	if req == nil {
-		return nil, errors.New("payload: missing")
-	}
-
 	if err := req.Validate(); err != nil {
 		return nil, err
 	}
-
+	if stub.Ok(ctx) {
+		return c.chargesStub.Cancel(ctx, req)
+	}
 	return c.charges.Cancel(ctx, req)
 }
 
@@ -93,13 +90,11 @@ func (c Client) CancelCharge(ctx context.Context, req *entity.CancelChargeReq) (
 //
 // Reference: https://commerce.coinbase.com/docs/api/#resolve-a-charge
 func (c Client) ResolveCharge(ctx context.Context, req *entity.ResolveChargeReq) (*entity.ResolveChargeResp, error) {
-	if req == nil {
-		return nil, errors.New("payload: missing")
-	}
-
 	if err := req.Validate(); err != nil {
 		return nil, err
 	}
-
+	if stub.Ok(ctx) {
+		return c.chargesStub.Resolve(ctx, req)
+	}
 	return c.charges.Resolve(ctx, req)
 }