(PureBasic) QuickBooks - Automatically Refresh Access Token with No User Interaction

Demonstrates how to automaticaly refresh an expired access token and retry the request after a 401 authorization error.

Chilkat PureBasic Module Download Chilkat PureBasic Module

IncludeFile "CkJsonObject.pb"
IncludeFile "CkDateTime.pb"
IncludeFile "CkStringBuilder.pb"
IncludeFile "CkOAuth2.pb"
IncludeFile "CkRest.pb"
IncludeFile "CkDtObj.pb"

Procedure ChilkatExample()

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

    ; Get our previously obtained OAuth2 access token, which should contain JSON like this:
    ; {
    ;   "expires_in": 3600,
    ;   "x_refresh_token_expires_in": 8726400,
    ;   "refresh_token": "L011546037639r ... 3vR2DrbOmg0Sdagw",
    ;   "access_token": "eyJlbmMiOiJBMTI4Q0 ... oETJEMbeggg",
    ;   "token_type": "bearer"
    ; }

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

    success.i = CkJsonObject::ckLoadFile(jsonToken,"qa_data/tokens/qb-access-token.json")

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

    ; Connect using TLS.
    ; A single REST object, once connected, can be used for many Quickbooks REST API calls.
    ; The auto-reconnect indicates that if the already-established HTTPS connection is closed,
    ; then it will be automatically re-established as needed.
    bAutoReconnect.i = 1
    success = CkRest::ckConnect(rest,"sandbox-quickbooks.api.intuit.com",443,1,bAutoReconnect)
    If success <> 1
        Debug CkRest::ckLastErrorText(rest)
        CkJsonObject::ckDispose(jsonToken)
        CkRest::ckDispose(rest)
        ProcedureReturn
    EndIf

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

    CkStringBuilder::ckAppend(sbAuth,"Bearer ")
    CkStringBuilder::ckAppend(sbAuth,CkJsonObject::ckStringOf(jsonToken,"access_token"))
    CkRest::setCkAuthorization(rest, CkStringBuilder::ckGetAsString(sbAuth))

    CkRest::ckAddHeader(rest,"Accept","application/json")
    CkRest::setCkAllowHeaderFolding(rest, 0)

    ; The company ID is 123146096291789
    ; The employee ID is 58
    responseBody.s = CkRest::ckFullRequestNoBody(rest,"GET","/v3/company/123146096291789/employee/58?minorversion=45")
    If CkRest::ckLastMethodSuccess(rest) <> 1
        Debug CkRest::ckLastErrorText(rest)
        CkJsonObject::ckDispose(jsonToken)
        CkRest::ckDispose(rest)
        CkStringBuilder::ckDispose(sbAuth)
        ProcedureReturn
    EndIf

    ; If we get a 401 authorization error, then it's likely because the access token expired.
    ; We can automatically refresh it without interaction from the user.
    If CkRest::ckResponseStatusCode(rest) = 401

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

        CkOAuth2::setCkTokenEndpoint(oauth2, "https://oauth.platform.intuit.com/oauth2/v1/tokens/bearer")

        ; Replace these with actual values.
        CkOAuth2::setCkClientId(oauth2, "QUICKBOOKS-CLIENT-ID")
        CkOAuth2::setCkClientSecret(oauth2, "QUICKBOOKS-CLIENT-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)
            CkRest::ckDispose(rest)
            CkStringBuilder::ckDispose(sbAuth)
            CkOAuth2::ckDispose(oauth2)
            ProcedureReturn
        EndIf

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

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

        ; Save the new JSON access token response to a file.
        ; The access + refresh tokens contained in this JSON will be needed for the next refresh.
        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/qb-access-token.json","utf-8",0)

        Debug "OAuth2 token refreshed!"
        Debug "New Access Token = " + CkOAuth2::ckAccessToken(oauth2)

        CkStringBuilder::ckClear(sbAuth)
        CkStringBuilder::ckAppend(sbAuth,"Bearer ")
        CkStringBuilder::ckAppend(sbAuth,CkOAuth2::ckAccessToken(oauth2))
        CkRest::setCkAuthorization(rest, CkStringBuilder::ckGetAsString(sbAuth))

        ; Now retry the request with the refreshed access token...
        responseBody = CkRest::ckFullRequestNoBody(rest,"GET","/v3/company/123146096291789/employee/58?minorversion=45")
        If CkRest::ckLastMethodSuccess(rest) <> 1
            Debug CkRest::ckLastErrorText(rest)
            CkJsonObject::ckDispose(jsonToken)
            CkRest::ckDispose(rest)
            CkStringBuilder::ckDispose(sbAuth)
            CkOAuth2::ckDispose(oauth2)
            CkStringBuilder::ckDispose(sbJson)
            ProcedureReturn
        EndIf

    EndIf

    ; We should expect a 200 response if successful.
    If CkRest::ckResponseStatusCode(rest) <> 200
        Debug "Request Header: "
        Debug CkRest::ckLastRequestHeader(rest)
        Debug "----"
        Debug "Response StatusCode = " + Str(CkRest::ckResponseStatusCode(rest))
        Debug "Response StatusLine: " + CkRest::ckResponseStatusText(rest)
        Debug "Response Header:"
        Debug CkRest::ckResponseHeader(rest)
        Debug responseBody
        CkJsonObject::ckDispose(jsonToken)
        CkRest::ckDispose(rest)
        CkStringBuilder::ckDispose(sbAuth)
        CkOAuth2::ckDispose(oauth2)
        CkStringBuilder::ckDispose(sbJson)
        ProcedureReturn
    EndIf

    ; Load the JSON response into a JSON object for parsing.
    ; A sample JSON response is shown below.
    json.i = CkJsonObject::ckCreate()
    If json.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkJsonObject::ckLoad(json,responseBody)

    ; These will be used for parsing date/time strings..
    dtime.i = CkDateTime::ckCreate()
    If dtime.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    bLocalTime.i = 1
    dt.i

    ; Show the JSON.   
    CkJsonObject::setCkEmitCompact(json, 0)
    Debug CkJsonObject::ckEmit(json)

    ; Get some information from the JSON..
    Debug "Name: " + CkJsonObject::ckStringOf(json,"Employee.DisplayName")
    Debug "Id: " + CkJsonObject::ckStringOf(json,"Employee.Id")
    Debug "City: " + CkJsonObject::ckStringOf(json,"Employee.PrimaryAddr.City")
    Debug "PostalCode: " + CkJsonObject::ckStringOf(json,"Employee.PrimaryAddr.PostalCode")

    ; Load the CreateTime into a CkDateTime...
    CkDateTime::ckSetFromTimestamp(dtime,CkJsonObject::ckStringOf(json,"Employee.MetaData.CreateTime"))
    dt = CkDateTime::ckGetDtObj(dtime,bLocalTime)
    Debug Str(CkDtObj::ckMonth(dt)) + "/" + Str(CkDtObj::ckDay(dt)) + "/" + Str(CkDtObj::ckYear(dt)) + "  " + Str(CkDtObj::ckHour(dt)) + ":" + Str(CkDtObj::ckMinute(dt))
    CkDtObj::ckDispose(dt)

    Debug "Success."

    ; Use this online tool to generate parsing code from sample JSON: 
    ; Generate Parsing Code from JSON

    ; ------------------------------------------------------
    ; The JSON response looks like this:

    ; {
    ;   "Employee": {
    ;     "SSN": "XXX-XX-XXXX",
    ;     "PrimaryAddr": {
    ;       "Id": "116",
    ;       "Line1": "45 N. Elm Street",
    ;       "City": "Middlefield",
    ;       "CountrySubDivisionCode": "CA",
    ;       "PostalCode": "93242"
    ;     },
    ;     "BillableTime": false,
    ;     "domain": "QBO",
    ;     "sparse": false,
    ;     "Id": "98",
    ;     "SyncToken": "0",
    ;     "MetaData": {
    ;       "CreateTime": "2015-07-24T09:34:35-07:00",
    ;       "LastUpdatedTime": "2015-07-24T09:34:35-07:00"
    ;     },
    ;     "GivenName": "Bill",
    ;     "FamilyName": "Miller",
    ;     "DisplayName": "Bill Miller",
    ;     "PrintOnCheckName": "Bill Miller",
    ;     "Active": true,
    ;     "PrimaryPhone": {
    ;       "FreeFormNumber": "234-525-1234"
    ;     }
    ;   },
    ;   "time": "2015-07-24T09:35:54.805-07:00"
    ; 


    CkJsonObject::ckDispose(jsonToken)
    CkRest::ckDispose(rest)
    CkStringBuilder::ckDispose(sbAuth)
    CkOAuth2::ckDispose(oauth2)
    CkStringBuilder::ckDispose(sbJson)
    CkJsonObject::ckDispose(json)
    CkDateTime::ckDispose(dtime)


    ProcedureReturn
EndProcedure