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Tcl

USPS OAuth2 Client Credentials

See more OAuth2 Examples

Get an OAuth2 access token for the United States Postal Service (USPS) REST API.

Chilkat Tcl Downloads

Tcl

load ./chilkat.dll

set success 0

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

set http [new_CkHttp]

# Implements the following CURL command:

# curl -X POST https://apis.usps.com/oauth2/v3/token \
#   -H "Content-Type: application/x-www-form-urlencoded" \
#   -d "grant_type=client_credentials" \
#   -d "client_id=123456789" \
#   -d "client_secret=A1B2C3D4E5" \
#   -d "scope=ResourceA+ResourceB+ResourceC"

# Use the following online tool to generate HTTP code from a CURL command
# Convert a cURL Command to HTTP Source Code

set req [new_CkHttpRequest]

CkHttpRequest_AddParam $req "grant_type" "client_credentials"
CkHttpRequest_AddParam $req "client_id" "123456789"
CkHttpRequest_AddParam $req "client_secret" "A1B2C3D4E5"
CkHttpRequest_AddParam $req "scope" "ResourceA+ResourceB+ResourceC"

CkHttpRequest_put_HttpVerb $req "POST"
CkHttpRequest_put_ContentType $req "application/x-www-form-urlencoded"

set resp [new_CkHttpResponse]

set success [CkHttp_HttpReq $http "https://apis.usps.com/oauth2/v3/token" $req $resp]
if {$success == 0} then {
    puts [CkHttp_lastErrorText $http]
    delete_CkHttp $http
    delete_CkHttpRequest $req
    delete_CkHttpResponse $resp
    exit
}

set sbResponseBody [new_CkStringBuilder]

CkHttpResponse_GetBodySb $resp $sbResponseBody

set jResp [new_CkJsonObject]

CkJsonObject_LoadSb $jResp $sbResponseBody
CkJsonObject_put_EmitCompact $jResp 0

puts "Response Body:"
puts [CkJsonObject_emit $jResp]

set respStatusCode [CkHttpResponse_get_StatusCode $resp]
puts "Response Status Code = $respStatusCode"
if {$respStatusCode >= 400} then {
    puts "Response Header:"
    puts [CkHttpResponse_header $resp]
    puts "Failed."
    delete_CkHttp $http
    delete_CkHttpRequest $req
    delete_CkHttpResponse $resp
    delete_CkStringBuilder $sbResponseBody
    delete_CkJsonObject $jResp
    exit
}

# Sample JSON response:
# (Sample code for parsing the JSON response is shown below)

# {
#   "access_token": "eyJraWQiOiIxMDEwMTAiLCJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiJ9.eyJzdWIiOiIiLCJhdWQiOiJhZGRyZXNzZXMgaW50ZXJuYXRpb25hbC1wcmljZXMgc3Vic2NyaXB0aW9ucyBwYXltZW50cyBwaWNrdXAgdHJhY2tpbmcgbGFiZWxzIHNjYW4tZm9ybXMgY29tcGFuaWVzIHNlcnZpY2UtZGVsaXZlcnktc3RhbmRhcmRzIGxvY2F0aW9ucyBpbnRlcm5hdGlvbmFsLWxhYmVscyBwcmljZXMiLCJhenAiOiJoeXI3YjN2Q1J0cFl0QUhNMWE4Y2RVcmt5eUZtTmtiZyIsIm9yZ2FuaXphdGlvbl9pZCI6IjAiLCJpc3MiOiJ1cm46XC9cL2FwaS51c3BzLmNvbSIsImV4cCI6MTY4MDkxNzc4NiwiaWF0IjoxNjgwODg4OTg2LCJqdGkiOiI3YjU5MzJlMS05NjIxLTQzZDAtYTMyNy0xMzIxYWVjNzJjZGYifQ.QzrUxlT2rG4jvYbMDGnk23j8ZYfHJcdXPKR9CbSmcKeVpURaHhEMpPB6K4x5ut3xxeEGSzeE5VRz8vixI4iqyHsD8rSdkLTPHy0iovUHOZQBAJVQ6hii9jpLhxUXmiTtH3jKzSj_f2fuNmZbIGhf-CR2FBeWF-aBPzEDEMV95nkCUMfW_Z2BmkbraSfvQZxkCO-cLrMAwlYcrzUtaJ7vnazeQB4sep5BBHBEvsa4kfq6_tz6BAKgv3R7cI2NkSv-wgy_IGoTjVCMTS8mJHGs_t8cWCO8-z4lxW1tUwIBKOCUDpmEEnGgiG6Sl0C_gGl4bZ5cDSl4IgPpcOVi9jZ7LA",
#   "token_type": "Bearer",
#   "issued_at": 1680888985929,
#   "expires_in": 28799,
#   "status": "approved",
#   "scope": "addresses international-prices subscriptions payments pickup tracking labels scan-forms companies service-delivery-standards locations international-labels prices",
#   "issuer": "api.usps.com",
#   "client_id": "hyr7b3vCRtpYtAHM1a8cdUrkyyFmNkbg",
#   "application_name": "Silver Shipper Developer",
#   "api_products": "[Shipping-Silver]",
#   "public_key": "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"
# }

# Sample code for parsing the JSON response...
# Use the following online tool to generate parsing code from sample JSON:
# Generate Parsing Code from JSON

set access_token [CkJsonObject_stringOf $jResp "access_token"]
set token_type [CkJsonObject_stringOf $jResp "token_type"]
set issued_at [CkJsonObject_IntOf $jResp "issued_at"]
set expires_in [CkJsonObject_IntOf $jResp "expires_in"]
set status [CkJsonObject_stringOf $jResp "status"]
set scope [CkJsonObject_stringOf $jResp "scope"]
set issuer [CkJsonObject_stringOf $jResp "issuer"]
set client_id [CkJsonObject_stringOf $jResp "client_id"]
set application_name [CkJsonObject_stringOf $jResp "application_name"]
set api_products [CkJsonObject_stringOf $jResp "api_products"]
set public_key [CkJsonObject_stringOf $jResp "public_key"]

delete_CkHttp $http
delete_CkHttpRequest $req
delete_CkHttpResponse $resp
delete_CkStringBuilder $sbResponseBody
delete_CkJsonObject $jResp