Golang client for PayPal REST API

Sometimes paypal returns errors like:

400 Invalid request - see details

And we have to type assert the error to get the details field but currently, in README.md there's no examples of error handling.

What does this PR do?

• add ctx argument to all request functions
• update module version to v4
• update minimum go version to 1.13
• add GetWebhookEventTypes (in separate commit)

these two integrations tests fails the same way before and after the change.

-- FAIL: TestCreateVenmoPayout (0.51s)
    integration_test.go:69:
        	Error Trace:	integration_test.go:69
        	Error:      	Received unexpected error:
        	            	POST https://api.sandbox.paypal.com/v1/payments/payouts: 400 User business error., []
        	Test:       	TestCreateVenmoPayout
        	Messages:   	should accept venmo wallet
    assertion_compare.go:211:
        	Error Trace:	integration_test.go:70
        	Error:      	"0" is not greater than "0"
        	Test:       	TestCreateVenmoPayout
        	Messages:   	[]
--- FAIL: TestStoreCreditCard (0.67s)
    integration_test.go:119: 200 code expected for valid CC card. Error: POST https://api.sandbox.paypal.com/v1/vault/credit-cards: 400 Invalid request - see details, [{Field:expire_month, expire_year Issue:Invalid expiration (cannot be in the past) Links:[]}]

I created this patch using this script + fix all resulting compiler errors:

files="authorization.go billing.go identity.go order.go payout.go products.go sale.go subscription.go subscription_plan.go transaction_search.go vault.go webhooks.go webprofile.go"

sed -i 's/c.NewRequest(/c.NewRequest(ctx, /' ${files}
sed -i 's/http.NewRequest(/http.NewRequestWithContext(ctx, /' ${files} client.go
sed -r -i 's/func \(c \*Client\) ([^(]+)\((.*)/func (c *Client) \1\(ctx context.Context, \2/g' ${files}

goimports -w .

thanks for your paypal sdk for go! paypal has upgraded some api (Payments/Orders) to Version 2 and recommend to upgrade to Version 2; Is there a plan to support Version 2?

According to the documentation, returned struct from the endpoint // Endpoint: GET /v2/checkout/orders/ID is incomplete (PurchaseUnit, Shipping Address).

Please add missing fields (shipping info, also shipping address JSON keys are invalid - line_1 instead of address_line_1, etc.), CapturedPurchaseUnit instead of `PurchaseUnit, etc.

Hi I am currently trying out this sdk before we decide to use it for our team, but I am unable to perform capture order correctly because fields like Billing Address and Security code in card information are not provided as part of the sandbox accounts. Can someone please help me unblock this ?

We have already released v2, which means things are slightly different for us.

Based on the suggestions here: https://github.com/golang/go/wiki/Modules#releasing-modules-v2-or-higher

We will go with the branch strategy.

We will not create a new branch since we dont have CLI this should not break anyone since there is no reason to go get -u this package.

LMK if you think we might be better off doing the directory version of support.

Once we have this in place we can start a bit of refactoring :)

I recently misinterpreted Paypal documentation causing me to treat the ID field for a capture response as a unique identifier for the capture event and not the order id. It occurs to me that this type of mistake would be harder to make if instead of strings the responses had type aliases defined.

For instance:

type OrderID string

// CaptureOrderResponse is the response for capture order
CaptureOrderResponse struct {
	ID            OrderID                 `json:"id,omitempty"`
	Status        string                 `json:"status,omitempty"`
	Payer         *PayerWithNameAndPhone `json:"payer,omitempty"`
	Address       *Address               `json:"address,omitempty"`
	PurchaseUnits []CapturedPurchaseUnit `json:"purchase_units,omitempty"`
}

This would help the code be more self-documenting and hopefully prevent the issue I ran into. I am interested to hear your thoughts or suggestions on this?

If it's acceptable, I would be happy to prep a PR targeting all order id fields in the defined payloads and swap with this new type.

This was a requirement on a project I worked on, not sure if this will be helpful to the greater community? Thanks a lot for the great codebase. Cheers :)

p, _ := paypal.NewClient("myClientId", "mySecret", paypal.APIBaseLive)
token, _ = p.GetAccessToken()

This code works just fine, in token var i got bearer token in key "access_token". And i have 17 length id that i got after made payment. How can i get status or something of this payment with this code?

What does this PR do?

This PR adds name and message fields into ErrorResponseDetail struct.

Where should the reviewer start?

types.go

How should this be manually tested?

Unmarshal an example response below using the ErrorResponse struct.

Any background context you want to provide?

These fields are not documented anywhere in the official documentation yet, but actually exists in an errored response:

{
  "name": "BUSINESS_ERROR",
  "debug_id": "[REDACTED]",
  "message": "Business error",
  "information_link": "https://developer.paypal.com/webapps/developer/docs/api/#BUSINESS_ERROR",
  "details": [
    {
      "name": "TOKEN_NOT_FOUND",
      "message": "Not Found: Invalid BA-Token Identifier"
    }
  ]
}

What does this PR do?

Adds function to allow users to cancel billing agreements with the id and a note (reason)

Where should the reviewer start?

The function is just hitting the cancel endpoint with an id

How should this be manually tested?

The function is hitting the endpoint with an id, there is a unit test as well

Any background context you want to provide?

follow api at https://developer.paypal.com/docs/limited-release/reference-transactions/#cancel-billing-agreement

Hi. Thanks for your great job.

Do you plan to replace application_context with https://developer.paypal.com/docs/api/orders/v2/#definition-application_context with experience_context ?

Thanks.

The order is being created as in the testing (because the docs are not updated) and returning 401 authentication failed when creating an order

c, err := paypal.NewClient(
  clientId,
  secret,
  paypal.APIBaseSandBox,
)
if err != nil {
  panic(err)
}
// c.SetLog(os.Stdout)

ApplicationContext := &paypal.ApplicationContext{
  BrandName: "Imajo Broqueles",
  Locale:    "es-MX",
}

OrderPayer := &paypal.CreateOrderPayer{}

PurchaseUnit := paypal.PurchaseUnitRequest{
  Amount: &paypal.PurchaseUnitAmount{
    Currency: "MXN",
    Value:    "100.00",
    Breakdown: &paypal.PurchaseUnitAmountBreakdown{
      ItemTotal: &paypal.Money{Currency: "MXN", Value: "100.00"},
    },
  },
}

// Create a new order

paypalOrder, err := c.CreateOrder(
  context.Background(),
  paypal.OrderIntentCapture,
  []paypal.PurchaseUnitRequest{PurchaseUnit},
  OrderPayer,
  ApplicationContext,
)

if err != nil {
  fmt.Println(err)
  return
}

A comment string`that looks something like this so they are clearly marked in godoc

// Deprecated: This API resource is deprecated by PayPal.

Just to make godoc clearer like this https://pkg.go.dev/github.com/plutov/paypal/v4#Resource