OpenInsight code to check mailgun for bounced email messages.

mailgun_check_bounce.oibp

Function mailgun_check_bounce(params)
/************************************************************************************************
* Name       :  MAILGUN_CHECK_BOUNCE
*
* Description:  Simple example problem to query the MailGun email server to check for if the
*               specified email address bounced and get the reason why.
*               Program demonstrates the use of WinHTTP COM Object and JSON values.
*
*               Example use only. Requires configuration of static variables for example.
*               Set CheckAddressBounced, APIKey, APIDomain before use.
*              
* Parameters:
*   none
*
* Returns:
*   none
*
* History (Date, Initials, Notes)
* 08/20/14    JAB    Jared Bratu, Congruity Service
*
************************************************************************************************/
 
Declare Function RTI_JSON
 
Equ MAILGUN_ADDRESS_NOT_FOUND$ To "Address not found in bounces table"
Equ MAILGUN_AUTH_FORBIDDEN$    To "Forbidden"
Equ TRUE$ To 1
Equ FALSE$ To 0
 
*Address to check. Check if email sent to this address bounced.
CheckAddressBounced = '[email protected]'
 
*The mailgun private API Key available on the control panel
APIKey      = "key-replacewithyourapikey" ;* Replace with your key
APIUserName = "api" ;*This should always be 'api' as per mailgun docs
 
*The mailgun account domain the CheckAddresBounce address was sent through
APIDomain   = "openinsight.congruityservice.com" ;* Replace with your domain
 
*Construct the API URL call according to the MailGun docs
*http://documentation.mailgun.com/api-bounces.html#bounces
APIUrl      = "https://api.mailgun.net/v2/" : APIDomain : "/bounces/" : CheckAddressBounced
 
*Break to debug on error
DebugOnError = TRUE$
 
LOG = "Checking if " : CheckAddressBounced : " bounced."
Gosub mcbSetLog
 
*Construct an HTTP request and set the Open parameters
*http://msdn.microsoft.com/en-us/library/windows/desktop/aa383989(v=vs.85).aspx
oleObj = OleCreateInstance('WinHttp.WinHttpRequest.5.1')
oleResult = OleCallMethod(oleObj, "Open", 'GET', APIUrl, 0)
mcbStep = "Setting WinHTTP Open Parms" 
mcbStatus = OleStatus() ; Gosub mcbCheckStatus
 
*Optional - Setup timeout methods for resolving DNS and server response
*http://msdn.microsoft.com/en-us/library/windows/desktop/aa384061(v=vs.85).aspx
mcbStatus = OleCallMethod(oleObj, "SetTimeouts", 30000,15000,15000,15000) ;* All times in ms
mcbStep = "Setting timeout values" 
mcbStatus = OleStatus() ; Gosub mcbCheckStatus
 
*Specify the username and password to authenticate with the API as 
oleResult = OleCallMethod(oleObj, "SetCredentials", APIUserName, APIKey, 0)
status = OleStatus()
mcbStep = "Setting user and pass"  
mcbStatus = OleStatus() ; Gosub mcbCheckStatus
 
*Execute the API request call  
*Blocks until Timeout reached or response received
oleResult = OleCallMethod(oleObj, 'SEND')
mcbStep = "Executing request"  
mcbStatus = OleStatus() ; Gosub mcbCheckStatus
 
*Get the response value or error value
ResponseRAW = OleGetProperty(oleObj, 'ResponseText')
mcbStep = "Reading ResponseText"       
mcbStatus = OleStatus() ; Gosub mcbCheckStatus
 
*If authentication fails we don't get a JSON object
If ResponseRAW EQ MAILGUN_AUTH_FORBIDDEN$ Then
    LOG = "Unrecoverable authentication error"
    Gosub mcbSetLog
End Else
 
    bounce = ''
     
    *Branch will set bounce to true of bounced or false if not bounced
    Gosub mcbProcessResponse
     
End
 
If Unassigned(bounce) Then
    *Fatal error, couldn't determine bounce status
    *Check mcbLog variable for details
    debug
End Else
    If bounce = TRUE$ Then
        *Message bounced
        *see mcbLog variable for details
    End Else
        *Message did not bounce
    End
End
 
debug
 
Return
*
*End MAILGUN_CHECK_BOUNCE
*
 
*
* Branch handles a successful API call.
*
* Requires:
* ResponseRAW
*
* Returns:
* Bounce
*
mcbProcessResponse:
 
*Turn the raw response into a JSON object for manipulation 
RetObj = RTI_JSON(ResponseRAW, 'Parse')
ResponseMessage = RTI_JSON(RetObj, "GetValue", "message")
 
If ResponseMessage EQ MAILGUN_ADDRESS_NOT_FOUND$ Then
    bounce = FALSE$
     
    mcbLog = "Address " : CheckAddressBounced : " did not bounce"
    Gosub mcbSetLog
End Else
    bounce = TRUE$
     
    RetObjValues = RTI_JSON(RetObj, "GetObject", "bounce")
    bounce_code = RTI_JSON(RetObjValues, 'GetValue', 'code')
    bounce_error = RTI_JSON(RetObjValues, 'GetValue', 'error')
    bounce_address = RTI_JSON(RetObjValues, 'GetValue', 'address')
    mcbLog = "Address " : bounce_address : " bounced with error " : bounce_code : ". Error: " : bounce_error
    Gosub mcbSetLog
End
 
Return;*etiwagapomd
 
*
* Branch to log errors into LOG
*
mcbCheckStatus:
*mcb = MailGun Check Bounce
 
    If mcbStatus then
        Log = mcbStep : ' code: ': mcbStatus
         
        * If we want to break on error then
        * reference the error variables for easy access
        If DebugOnError EQ TRUE$ Then
            LOG_ALL = mcbLog
            LOG_LAST = Log
            debug
        End
         
        Gosub mcbSetLog
    End
     
Return ;*etiwagapomd
 
*
* Simple concatenation or logging function.
*
mcbSetLog:
    If Unassigned(mcbLog) Then
        mcbLog = LOG
    End Else
        mcbLog<-1> = LOG
    End
Return ;*etiwagapomd