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Tcl

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.

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Tcl

load ./chilkat.dll

set success 0

# To further clarify, see OAuth 2.0 Authorization Flow

set oauth2 [new_CkOAuth2]

# 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.
CkOAuth2_put_ListenPort $oauth2 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.
CkOAuth2_put_AuthorizationEndpoint $oauth2 "https://chilkat.myshopify.com/admin/oauth/authorize"
CkOAuth2_put_TokenEndpoint $oauth2 "https://chilkat.myshopify.com/admin/oauth/access_token"

# Replace this with your actual API KEY (client ID)
CkOAuth2_put_ClientId $oauth2 "SHOPIFY_API_KEY"

# This is for Require Proof Key for Code Exchange (PKCE)
# See OAuth2 PKCE Explained
CkOAuth2_put_CodeChallenge $oauth2 1
CkOAuth2_put_CodeChallengeMethod $oauth2 "S256"

# Set requested scopes.  See https://help.shopify.com/api/getting-started/authentication/oauth
CkOAuth2_put_Scope $oauth2 "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.
set url [CkOAuth2_startAuth $oauth2]
if {[CkOAuth2_get_LastMethodSuccess $oauth2] != 1} then {
    puts [CkOAuth2_lastErrorText $oauth2]
    delete_CkOAuth2 $oauth2
    exit
}

# Launch the default browser on the system and navigate to the url.
# The LaunchBrowser method was added in Chilkat v10.1.2.
set success [CkOAuth2_LaunchBrowser $oauth2 $url]
if {$success == 0} then {
    puts [CkOAuth2_lastErrorText $oauth2]
    delete_CkOAuth2 $oauth2
    exit
}

# Wait for the user to approve or deny authorization in the browser.
set numMsWaited 0
while {expr [$numMsWaited < 90000]  &&  [[CkOAuth2_get_AuthFlowState $oauth2] < 3]} {
    CkOAuth2_SleepMs $oauth2 100
    set numMsWaited [expr $numMsWaited + 100]
}

# 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 {[CkOAuth2_get_AuthFlowState $oauth2] < 3} then {
    CkOAuth2_Cancel $oauth2
    puts "No response from the browser!"
    delete_CkOAuth2 $oauth2
    exit
}

# 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 {[CkOAuth2_get_AuthFlowState $oauth2] == 5} then {
    puts "OAuth2 failed to complete."
    puts [CkOAuth2_failureInfo $oauth2]
    delete_CkOAuth2 $oauth2
    exit
}

if {[CkOAuth2_get_AuthFlowState $oauth2] == 4} then {
    puts "OAuth2 authorization was denied."
    puts [CkOAuth2_accessTokenResponse $oauth2]
    delete_CkOAuth2 $oauth2
    exit
}

if {[CkOAuth2_get_AuthFlowState $oauth2] != 3} then {
    puts "Unexpected AuthFlowState:[CkOAuth2_get_AuthFlowState $oauth2]"
    delete_CkOAuth2 $oauth2
    exit
}

puts "OAuth2 authorization granted!"
puts "Access Token = [CkOAuth2_accessToken $oauth2]"

# Save the full JSON access token response to a file.
set sbJson [new_CkStringBuilder]

CkStringBuilder_Append $sbJson [CkOAuth2_accessTokenResponse $oauth2]
CkStringBuilder_WriteFile $sbJson "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"
# }

delete_CkOAuth2 $oauth2
delete_CkStringBuilder $sbJson