Go

Egyptian eReceipt OAuth2 Client Credentials

See more Egypt eReceipt Examples

Get an OAuth2 access token for the Egyptian eReceipt REST API using client credentials (no interactivity with a web browser required). Go

    success := false

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

    http := chilkat.NewHttp()

    // Note: Any provider of a REST API, such as the Egyptian government in this case, can make life 
    // much easier for developers by providing one or more of the following in the API documentation:
    // 
    // 1) A sample CURL statement for each API call.
    // 2) A Postman collection, or Swagger/OpenAPI specification file.
    // 3) A sample of a raw HTTP request and response for each API call.
    // 
    // The sample CURL statements or raw HTTP request/responses do not need to comprehensively show all 
    // possible options.  Providing a sample allows one to quickly make a successful API call.
    // It also allows for code generation directly from the CURL, Postman collection, or raw request/response,
    // and it tends to answer all questions about the format/structure of a request that, suprisingly,
    // remain ambiguous or not obvious in other forms of documentation.

    req := chilkat.NewHttpRequest()
    req.AddParam("grant_type","client_credentials")
    // Use your actual client ID and client secret...
    req.AddParam("client_id","d0394a9f-0607-40de-a978-2d3eb8375b04")
    req.AddParam("client_secret","6d62315e-d65a-4e41-9112-4195ea834edf")

    req.AddHeader("posserial","1234567899")
    req.AddHeader("pososversion","os")
    req.AddHeader("posmodelframework","1")
    req.AddHeader("presharedkey","03ac674216f3e1...")

    // When writing this example, the documentation at https://sdk.invoicing.eta.gov.eg/ereceiptapi/01-authenticate-pos/
    // shows us the HTTP verb and path (POST /connect/token), however,
    // we don't see the actual domain where the request is to be sent.
    // What are the endpoints???
    // It took some searching, but we found some endpoints here:  https://sdk.invoicing.eta.gov.eg/faq/
    // It's not immediately apparent which endpoint is to be used with a given API call.
    // Why not just include the endpoint in the documentation for each REST API call?
    // Endpoints are literally the #1 thing that needs to be known.
    // They can't just be buried in a FAQ.  They should be up-front and obvious.
    // 
    // So.. we're guessing the endpoint is likely "https://invoicing.eta.gov.eg/connect/token"
    req.SetHttpVerb("POST")
    req.SetContentType("application/x-www-form-urlencoded")

    resp := chilkat.NewHttpResponse()
    success = http.HttpReq("https://invoicing.eta.gov.eg/connect/token",req,resp)
    if success == false {
        fmt.Println(http.LastErrorText())
        http.DisposeHttp()
        req.DisposeHttpRequest()
        resp.DisposeHttpResponse()
        return
    }

    sbResponseBody := chilkat.NewStringBuilder()
    resp.GetBodySb(sbResponseBody)

    jResp := chilkat.NewJsonObject()
    jResp.LoadSb(sbResponseBody)
    jResp.SetEmitCompact(false)

    fmt.Println("Response Body:")
    fmt.Println(*jResp.Emit())

    respStatusCode := resp.StatusCode()
    fmt.Println("Response Status Code = ", respStatusCode)
    if respStatusCode >= 400 {
        fmt.Println("Response Header:")
        fmt.Println(resp.Header())
        fmt.Println("Failed.")
        http.DisposeHttp()
        req.DisposeHttpRequest()
        resp.DisposeHttpResponse()
        sbResponseBody.DisposeStringBuilder()
        jResp.DisposeJsonObject()
        return
    }

    // If successful, the OAuth2 access token JSON looks like this:

    // {
    //   "token_type": "Bearer",
    //   "access_token": "eyJraW......R2sbqrY",
    //   "expires_in": "3600",
    //   "scope": "..."
    // }

    token_type := jResp.StringOf("token_type")
    access_token := jResp.StringOf("access_token")
    expires_in := jResp.StringOf("expires_in")
    scope := jResp.StringOf("scope")

    http.DisposeHttp()
    req.DisposeHttpRequest()
    resp.DisposeHttpResponse()
    sbResponseBody.DisposeStringBuilder()
    jResp.DisposeJsonObject()