(Go) PayPal -- Get an OAuth 2.0 Access Token

Demonstrates how to send a request to get a PayPal OAuth2 access token. Sends an HTTP request equivalent to the following:

curl https://api.sandbox.paypal.com/v1/oauth2/token \
  -H "Accept: application/json" \
  -H "Accept-Language: en_US" \
  -u "Client-Id:Secret" \
  -d "grant_type=client_credentials"

Chilkat Go Downloads Go Package for Windows, MacOS, Linux, Alpine Linux, Solaris

    // Note: Requires Chilkat v9.5.0.64 or greater.

    // This requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    rest := chilkat.NewRest()

    // Make the initial connection.
    // A single REST object, once connected, can be used for many PayPal REST API calls.
    // The auto-reconnect indicates that if the already-established HTTPS connection is closed,
    // then it will be automatically re-established as needed.
    bAutoReconnect := true
    success := rest.Connect("api.sandbox.paypal.com",443,true,bAutoReconnect)
    if success != true {
        fmt.Println(rest.LastErrorText())
        rest.DisposeRest()
        return
    }

    // Duplicate this request:

    // 	curl https://api.sandbox.paypal.com/v1/oauth2/token \
    // 	  -H "Accept: application/json" \
    // 	  -H "Accept-Language: en_US" \
    // 	  -u "Client-Id:Secret" \
    // 	  -d "grant_type=client_credentials"

    rest.AddHeader("Accept","application/json")
    rest.AddHeader("Accept-Language","en_US")

    // For additional help on where to find  your client ID and API secret, see PayPal Client_ID and API_Secret
    rest.SetAuthBasic("PAYPAL_REST_API_CLIENT_ID","PAYPAL_REST_API_SECRET")

    rest.AddQueryParam("grant_type","client_credentials")

    responseStr := rest.FullRequestFormUrlEncoded("POST","/v1/oauth2/token")
    if rest.LastMethodSuccess() != true {
        fmt.Println(rest.LastErrorText())
        rest.DisposeRest()
        return
    }

    fmt.Println(rest.LastRequestHeader())

    // A sample response:

    // 	{
    // 	  "scope": "https://api.paypal.com/v1/payments/.* https://api.paypal.com/v1/vault/credit-card https://api.paypal.com/v1/vault/credit-card/.*",
    // 	  "access_token": "EEwJ6tF9x5WCIZDYzyZGaz6Khbw7raYRIBV_WxVvgmsG",
    // 	  "token_type": "Bearer",
    // 	  "app_id": "APP-6XR95014BA15863X",
    // 	  "expires_in": 28800
    // 	}

    json := chilkat.NewJsonObject()
    json.Load(*responseStr)
    json.SetEmitCompact(false)

    // Check the response status code.  A 200 indicates success..
    if rest.ResponseStatusCode() != 200 {
        fmt.Println(*json.Emit())
        fmt.Println("Failed.")
        rest.DisposeRest()
        json.DisposeJsonObject()
        return
    }

    // Given that the access token expires in approx 8 hours,
    // let's record the date/time this token was created.
    // This will allow us to know beforehand if the token
    // is expired (and we can then fetch a new token).
    dateTime := chilkat.NewCkDateTime()
    bLocalTime := false
    dtNow := dateTime.GetAsUnixTime(bLocalTime)
    json.AppendInt("tokenCreateTimeUtc",dtNow)

    // Examine the access token and save to a file.
    fmt.Println("Access Token: ", *json.StringOf("access_token"))
    fmt.Println("Full JSON Response:")
    fmt.Println(*json.Emit())

    sbResponse := chilkat.NewStringBuilder()
    sbResponse.Append(*json.Emit())
    bEmitBom := false
    sbResponse.WriteFile("qa_data/tokens/paypal.json","utf-8",bEmitBom)

    rest.DisposeRest()
    json.DisposeJsonObject()
    dateTime.DisposeCkDateTime()
    sbResponse.DisposeStringBuilder()