(PureBasic) MercadoLibre Refresh OAuth2 Access Token

Demonstrates how to refresh a MercadoLibre OAuth2 access token. The refresh does not require user interaction via a web browser. If an access token expires (typically with a 401 response code), a new access token can be automatically obtained by using the code in this example.

For more information, see https://developers.mercadolibre.com.ar/es_ar/autenticacion-y-autorizacion#Refresh-token

Chilkat PureBasic Module Download Chilkat PureBasic Module

IncludeFile "CkStringBuilder.pb"
IncludeFile "CkJsonObject.pb"
IncludeFile "CkOAuth2.pb"

Procedure ChilkatExample()

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

    ; It is assumed we previously obtained an OAuth2 access token.
    ; This example loads the JSON access token file 
    ; saved by this example: Get MercadoLibre OAuth2 Access Token

    jsonToken.i = CkJsonObject::ckCreate()
    If jsonToken.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success.i = CkJsonObject::ckLoadFile(jsonToken,"qa_data/tokens/mercadolibre.json")
    If success <> 1
        Debug "Failed to load mercadolibre.json"
        CkJsonObject::ckDispose(jsonToken)
        ProcedureReturn
    EndIf

    ; The access token JSON looks like this:

    ; {
    ;   "access_token": "APP_USR-8133606632685744-060115-93e1fd8b5e767c51c238df347bd0b288-577628017",
    ;   "token_type": "bearer",
    ;   "expires_in": 21600,
    ;   "scope": "offline_access read write",
    ;   "user_id": 577625107,
    ;   "refresh_token": "TG-5ad522a286f1200006ac4ed1-577625007"
    ; }

    oauth2.i = CkOAuth2::ckCreate()
    If oauth2.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkOAuth2::setCkTokenEndpoint(oauth2, "https://api.mercadolibre.com/oauth/token")

    ; Replace these with actual values.
    CkOAuth2::setCkClientId(oauth2, "MY_MERCADOLIBRE_APP_ID")
    CkOAuth2::setCkClientSecret(oauth2, "MY_MERCADOLIBRE_APP_SECRET")

    ; Get the "refresh_token"
    CkOAuth2::setCkRefreshToken(oauth2, CkJsonObject::ckStringOf(jsonToken,"refresh_token"))

    ; Send the HTTP POST to refresh the access token..
    success = CkOAuth2::ckRefreshAccessToken(oauth2)
    If success <> 1
        Debug CkOAuth2::ckLastErrorText(oauth2)
        CkJsonObject::ckDispose(jsonToken)
        CkOAuth2::ckDispose(oauth2)
        ProcedureReturn
    EndIf

    Debug "New access token: " + CkOAuth2::ckAccessToken(oauth2)
    Debug "New refresh token: " + CkOAuth2::ckRefreshToken(oauth2)

    ; Update the JSON with the new tokens.
    CkJsonObject::ckUpdateString(jsonToken,"access_token",CkOAuth2::ckAccessToken(oauth2))
    CkJsonObject::ckUpdateString(jsonToken,"refresh_token",CkOAuth2::ckRefreshToken(oauth2))

    ; Save the new JSON access token response to a file.
    sbJson.i = CkStringBuilder::ckCreate()
    If sbJson.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkJsonObject::setCkEmitCompact(jsonToken, 0)
    CkJsonObject::ckEmitSb(jsonToken,sbJson)
    CkStringBuilder::ckWriteFile(sbJson,"qa_data/tokens/mercadolibre.json","utf-8",0)

    Debug "OAuth2 authorization granted!"
    Debug "New Access Token = " + CkOAuth2::ckAccessToken(oauth2)


    CkJsonObject::ckDispose(jsonToken)
    CkOAuth2::ckDispose(oauth2)
    CkStringBuilder::ckDispose(sbJson)


    ProcedureReturn
EndProcedure