(PureBasic) Slack OAuth2

See more OAuth2 Examples

Note: This example requires Chilkat v10.1.2 or greater.

Chilkat PureBasic Module Download Chilkat PureBasic Module

IncludeFile "CkFileAccess.pb"
IncludeFile "CkJsonObject.pb"
IncludeFile "CkOAuth2.pb"

Procedure ChilkatExample()

    ; For more information about the OAuth2, see OAuth 2.0 Authorization Flow

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

    ; This example is for desktop applicatons (it is not for code that runs on a web server).

    ; Your applicaton must use your own public web server as an intermediate
    ; to receive and forward the redirect to localhost.
    ; See Using Your Web Server as an Intermediary for OAuth2 Redirect to localhost

    ; This is the Redirect URL defined for your Slack App in the Slack developer portal, and contains the above PHP.
    CkOAuth2::setCkAppCallbackUrl(oauth2, "https://yourwebserver.com/oauth2_redirect")
    CkOAuth2::setCkListenPort(oauth2, 3017)

    CkOAuth2::setCkAuthorizationEndpoint(oauth2, "https://slack.com/oauth/authorize")
    CkOAuth2::setCkTokenEndpoint(oauth2, "https://slack.com/api/oauth.access")

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

    CkOAuth2::setCkScope(oauth2, "team:read users:read")

    ; Begin the OAuth2 Authorization code flow.  This returns a URL that should be loaded in a browser.
    url.s = CkOAuth2::ckStartAuth(oauth2)
    If CkOAuth2::ckLastMethodSuccess(oauth2) <> 1
        Debug CkOAuth2::ckLastErrorText(oauth2)
        CkOAuth2::ckDispose(oauth2)
        ProcedureReturn
    EndIf

    Debug "url = " + url

    ; Launch the default browser on the system and navigate to the url.
    ; The LaunchBrowser method was added in Chilkat v10.1.2.
    success.i = CkOAuth2::ckLaunchBrowser(oauth2,url)
    If success = 0
        Debug CkOAuth2::ckLastErrorText(oauth2)
        CkOAuth2::ckDispose(oauth2)
        ProcedureReturn
    EndIf

    ; Wait for the user to approve or deny authorization in the browser.
    numMsWaited.i = 0
    While (numMsWaited < 90000) AND (CkOAuth2::ckAuthFlowState(oauth2) < 3)
        CkOAuth2::ckSleepMs(oauth2,100)
        numMsWaited = numMsWaited + 100
    Wend

    ; 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::ckAuthFlowState(oauth2) < 3
        CkOAuth2::ckCancel(oauth2)
        Debug "No response from the browser!"
        CkOAuth2::ckDispose(oauth2)
        ProcedureReturn
    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 CkOAuth2::ckAuthFlowState(oauth2) = 5
        Debug "OAuth2 failed to complete."
        Debug CkOAuth2::ckFailureInfo(oauth2)
        CkOAuth2::ckDispose(oauth2)
        ProcedureReturn
    EndIf

    If CkOAuth2::ckAuthFlowState(oauth2) = 4
        Debug "OAuth2 authorization was denied."
        Debug CkOAuth2::ckAccessTokenResponse(oauth2)
        CkOAuth2::ckDispose(oauth2)
        ProcedureReturn
    EndIf

    If CkOAuth2::ckAuthFlowState(oauth2) <> 3
        Debug "Unexpected AuthFlowState:" + Str(CkOAuth2::ckAuthFlowState(oauth2))
        CkOAuth2::ckDispose(oauth2)
        ProcedureReturn
    EndIf

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

    ; Get the full JSON response:
    json.i = CkJsonObject::ckCreate()
    If json.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkJsonObject::ckLoad(json,CkOAuth2::ckAccessTokenResponse(oauth2))
    CkJsonObject::setCkEmitCompact(json, 0)

    ; The JSON response looks like this:

    ; {
    ;   "ok": true,
    ;   "access_token": "xoxp-348475395242-348621810805-4768936228341-9f512b295124e7c9846ce63cb1464c4d",
    ;   "scope": "identify,team:read,users:read",
    ;   "user_id": "UA8HZRUPP",
    ;   "team_id": "TA3DZBN74",
    ;   "enterprise_id": null,
    ;   "team_name": "Chilkat Testing"
    ; }

    Debug CkJsonObject::ckEmit(json)

    ; Save the JSON to a file for future requests.
    fac.i = CkFileAccess::ckCreate()
    If fac.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkFileAccess::ckWriteEntireTextFile(fac,"qa_data/tokens/slack.json",CkJsonObject::ckEmit(json),"utf-8",0)


    CkOAuth2::ckDispose(oauth2)
    CkJsonObject::ckDispose(json)
    CkFileAccess::ckDispose(fac)


    ProcedureReturn
EndProcedure