Visual FoxPro Requires Chilkat v10.1.2+

Shopify OAuth2 Authentication

See more OAuth2 Examples

This example shows how to obtain an initial access token for a Shopify application using OAuth2 authentication specifically for non-web applications. This process requires displaying a browser window to secure user authorization. In contrast, web-based applications use a different method to obtain an OAuth2 token, as they redirect back to the application via a URL. Note: Once you have the access token, all subsequent Chilkat examples that rely on an already-obtained token are applicable to both web and non-web applications. Visual FoxPro

LOCAL lnSuccess
LOCAL loOauth2
LOCAL lcUrl
LOCAL lnNumMsWaited
LOCAL loSbJson

lnSuccess = 0

*  To further clarify, see OAuth 2.0 Authorization Flow

loOauth2 = CreateObject('Chilkat.OAuth2')

*  This should be the port in the localhost callback URL for your app.  
*  The callback URL would look like "http://localhost:3017/" if the port number is 3017.
*  Make sure that "http://localhost:3017/" is listed in your Whitelisted Redirection URLs for your Shopify app.
loOauth2.ListenPort = 3017

*  The full content of the Authorization Endpoin for Shopify looks like this:
*  https://{shop}.myshopify.com/admin/oauth/authorize?client_id={api_key}&scope={scopes}&redirect_uri={redirect_uri}&state={nonce}&grant_options[]={option}

*  Replace "chilkat" with your shop name.
loOauth2.AuthorizationEndpoint = "https://chilkat.myshopify.com/admin/oauth/authorize"
loOauth2.TokenEndpoint = "https://chilkat.myshopify.com/admin/oauth/access_token"

*  Replace this with your actual API KEY (client ID)
loOauth2.ClientId = "SHOPIFY_API_KEY"

*  This is for Require Proof Key for Code Exchange (PKCE)
*  See OAuth2 PKCE Explained
loOauth2.CodeChallenge = 1
loOauth2.CodeChallengeMethod = "S256"

*  Set requested scopes.  See https://help.shopify.com/api/getting-started/authentication/oauth
loOauth2.Scope = "read_product_listings,read_customers,read_orders,read_draft_orders"

*  Begin the OAuth2 Authorization code flow.  This returns a URL that should be loaded in a browser.
lcUrl = loOauth2.StartAuth()
IF (loOauth2.LastMethodSuccess <> 1) THEN
    ? loOauth2.LastErrorText
    RELEASE loOauth2
    CANCEL
ENDIF

*  Launch the default browser on the system and navigate to the url.
*  The LaunchBrowser method was added in Chilkat v10.1.2.
lnSuccess = loOauth2.LaunchBrowser(lcUrl)
IF (lnSuccess = 0) THEN
    ? loOauth2.LastErrorText
    RELEASE loOauth2
    CANCEL
ENDIF

*  Wait for the user to approve or deny authorization in the browser.
lnNumMsWaited = 0
DO WHILE (lnNumMsWaited < 90000) AND (loOauth2.AuthFlowState < 3)
    loOauth2.SleepMs(100)
    lnNumMsWaited = lnNumMsWaited + 100
ENDDO

*  If the browser does not respond within the specified time, AuthFlowState will be:
*  
*  1: Waiting for Redirect – The OAuth2 background thread is waiting for the browser's redirect request.
*  2: Waiting for Final Response – The thread is awaiting the final access token response.
*  In either case, cancel the background task initiated by StartAuth.

IF (loOauth2.AuthFlowState < 3) THEN
    loOauth2.Cancel()
    ? "No response from the browser!"
    RELEASE loOauth2
    CANCEL
ENDIF

*  Check AuthFlowState to determine if authorization was granted, denied, or failed:
*  
*  3: Success – OAuth2 flow completed, the background thread exited, and the successful response is in AccessTokenResponse.
*  4: Access Denied – OAuth2 flow completed, the background thread exited, and the error response is in AccessTokenResponse.
*  5: Failure – OAuth2 flow failed before completion, the background thread exited, and error details are in FailureInfo.

IF (loOauth2.AuthFlowState = 5) THEN
    ? "OAuth2 failed to complete."
    ? loOauth2.FailureInfo
    RELEASE loOauth2
    CANCEL
ENDIF

IF (loOauth2.AuthFlowState = 4) THEN
    ? "OAuth2 authorization was denied."
    ? loOauth2.AccessTokenResponse
    RELEASE loOauth2
    CANCEL
ENDIF

IF (loOauth2.AuthFlowState <> 3) THEN
    ? "Unexpected AuthFlowState:" + STR(loOauth2.AuthFlowState)
    RELEASE loOauth2
    CANCEL
ENDIF

? "OAuth2 authorization granted!"
? "Access Token = " + loOauth2.AccessToken

*  Save the full JSON access token response to a file.
loSbJson = CreateObject('Chilkat.StringBuilder')
loSbJson.Append(loOauth2.AccessTokenResponse)
loSbJson.WriteFile("qa_data/tokens/shopify-access-token.json","utf-8",0)

*  The saved JSON response looks like this:

*  {
*    "access_token": "1364e43a5332583188cb27bc85469b1f",
*    "scope": "read_product_listings,read_customers,read_orders,read_draft_orders"
*  }

RELEASE loOauth2
RELEASE loSbJson