(PureBasic) Xero Get Attachment (Download a Xero Attachment)

Demonstrates how to get the content of an attachment in Xero.

Note: This example requires Chilkat v9.5.0.64 or greater.

Chilkat PureBasic Module Download Chilkat PureBasic Module

IncludeFile "CkBinData.pb"
IncludeFile "CkXml.pb"
IncludeFile "CkStringBuilder.pb"
IncludeFile "CkRest.pb"

Procedure ChilkatExample()

    ; Note: Requires Chilkat v9.5.0.64 or greater.

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

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

    success.i

    ; Before sending REST API calls, the REST object needs to be
    ; initialized for OAuth1.
    ; See Xero 2-Legged OAuth1 Setup for sample code.

    ; Assuming the REST object's OAuth1 authenticator is setup, and the initial
    ; connection was made, we may now send REST HTTP requests..

    ; --------------------------------------------------------------
    ; First get a list of attachments for a given document (in this case a Receipt).

    endPoint.s = "Receipts"
    receiptID.s = "c4f40e59-c390-0001-caff-ce731c707d00"

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

    CkStringBuilder::ckAppend(sbPath,"/api.xro/2.0/{Endpoint}/{Guid}/Attachments/")
    numReplaced.i = CkStringBuilder::ckReplace(sbPath,"{Endpoint}",endPoint)
    numReplaced = CkStringBuilder::ckReplace(sbPath,"{Guid}",receiptID)

    responseXml.s = CkRest::ckFullRequestNoBody(rest,"GET",CkStringBuilder::ckGetAsString(sbPath))
    If CkRest::ckLastMethodSuccess(rest) <> 1
        Debug CkRest::ckLastErrorText(rest)
        CkRest::ckDispose(rest)
        CkStringBuilder::ckDispose(sbPath)
        ProcedureReturn
    EndIf

    ; A 200 response is expected for actual success.
    If CkRest::ckResponseStatusCode(rest) <> 200
        Debug responseXml
        CkRest::ckDispose(rest)
        CkStringBuilder::ckDispose(sbPath)
        ProcedureReturn
    EndIf

    ; Examine the response.
    Debug responseXml

    ; A sample response looks like this:

    ; 	<Response xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    ; 	  <Id>b235646f-34ac-4b15-90ce-d63267f7cd33</Id>
    ; 	  <Status>OK</Status>
    ; 	  <ProviderName>ChilkatPrivate</ProviderName>
    ; 	  <DateTimeUTC>2016-11-11T14:32:17.0908971Z</DateTimeUTC>
    ; 	  <Attachments>
    ; 	    <Attachment>
    ; 	      <AttachmentID>0edcddc8-325f-40c7-b950-8c71f14afc7c</AttachmentID>
    ; 	      <FileName>penguins.jpg</FileName>
    ; 	      <Url>http://api.xero.com/api.xro/2.0/Receipts/c4f40e59-c390-0001-caff-ce731c707d00/Attachments/penguins.jpg</Url>
    ; 	      <MimeType>image/jpg</MimeType>
    ; 	      <ContentLength>777835</ContentLength>
    ; 	    </Attachment>
    ; 	    <Attachment>
    ; 	      <AttachmentID>0adffdc8-325f-65c7-b950-4391f14af908</AttachmentID>
    ; 	      <FileName>starfish.jpg</FileName>
    ; 	      <Url>http://api.xero.com/api.xro/2.0/Receipts/c4f40e59-c390-0001-caff-ce731c707d00/Attachments/starfish.jpg</Url>
    ; 	      <MimeType>image/jpg</MimeType>
    ; 	      <ContentLength>24537</ContentLength>
    ; 	    </Attachment>
    ; 	  </Attachments>
    ; 	</Response>

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

    CkXml::ckLoadXml(xml,responseXml)

    ; Iterate over the attachments and download each.
    numRecords.i = CkXml::ckNumChildrenAt(xml,"Attachments")
    Debug "Number of Attachments = " + Str(numRecords)

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

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

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

    i.i = 0
    While i < numRecords
        CkXml::setCkI(xml, i)
        attachmentID.s = CkXml::ckGetChildContent(xml,"Attachments|Attachment[i]|AttachmentID")
        filename.s = CkXml::ckGetChildContent(xml,"Attachments|Attachment[i]|FileName")

        Debug "AttachmentID: " + attachmentID
        Debug "Filename: " + filename
        Debug "----"

        ; Download this attachment.
        ; First build the path for this particular attachment by appending the FileName to the path used to get the list of attachments.
        CkStringBuilder::ckClear(sbAttachmentPath)
        CkStringBuilder::ckAppendSb(sbAttachmentPath,sbPath)
        CkStringBuilder::ckAppend(sbAttachmentPath,filename)

        ; Send the GET request in one call, and then get the response in the next two.
        success = CkRest::ckSendReqNoBody(rest,"GET",CkStringBuilder::ckGetAsString(sbAttachmentPath))
        If success <> 1
            Debug CkRest::ckLastErrorText(rest)
            CkRest::ckDispose(rest)
            CkStringBuilder::ckDispose(sbPath)
            CkXml::ckDispose(xml)
            CkStringBuilder::ckDispose(sbSaveFilePath)
            CkStringBuilder::ckDispose(sbAttachmentPath)
            CkBinData::ckDispose(attachmentData)
            ProcedureReturn
        EndIf

        ; Get the response header.  If it's not a 200 success status code, then the response body does NOT contain
        ; the attachment data.
        statusCode.i = CkRest::ckReadResponseHeader(rest)
        If statusCode = -1
            ; We didn't get any response..
            Debug CkRest::ckLastErrorText(rest)
            CkRest::ckDispose(rest)
            CkStringBuilder::ckDispose(sbPath)
            CkXml::ckDispose(xml)
            CkStringBuilder::ckDispose(sbSaveFilePath)
            CkStringBuilder::ckDispose(sbAttachmentPath)
            CkBinData::ckDispose(attachmentData)
            ProcedureReturn
        EndIf

        If statusCode <> 200
            Debug "Response Status: " + Str(statusCode)
            responseBody.s = CkRest::ckReadRespBodyString(rest)
            If CkRest::ckLastMethodSuccess(rest) <> 1
                Debug "Failed to read the response body."
            Else
                Debug responseBody
            EndIf

            Debug "Failed."
            CkRest::ckDispose(rest)
            CkStringBuilder::ckDispose(sbPath)
            CkXml::ckDispose(xml)
            CkStringBuilder::ckDispose(sbSaveFilePath)
            CkStringBuilder::ckDispose(sbAttachmentPath)
            CkBinData::ckDispose(attachmentData)
            ProcedureReturn
        EndIf

        ; OK, the response header indicates the attachment content is forthcoming...
        ; There are a few ways to get the response body. If it is a very large attachment, it can be streamed directly
        ; to a file.  We'll assume it's not, so we'll get the response into a BinData object, and then save it to a file.
        CkBinData::ckClear(attachmentData)
        success = CkRest::ckReadRespBd(rest,attachmentData)
        If success <> 1
            Debug CkRest::ckLastErrorText(rest)
            CkRest::ckDispose(rest)
            CkStringBuilder::ckDispose(sbPath)
            CkXml::ckDispose(xml)
            CkStringBuilder::ckDispose(sbSaveFilePath)
            CkStringBuilder::ckDispose(sbAttachmentPath)
            CkBinData::ckDispose(attachmentData)
            ProcedureReturn
        EndIf

        ; Save the data to the file.
        CkStringBuilder::ckSetString(sbSaveFilePath,"qa_output/")
        CkStringBuilder::ckAppend(sbSaveFilePath,filename)
        success = CkBinData::ckWriteFile(attachmentData,CkStringBuilder::ckGetAsString(sbSaveFilePath))
        If success <> 1
            Debug "Failed to save to output file."
        Else
            Debug "Saved to " + CkStringBuilder::ckGetAsString(sbSaveFilePath)
        EndIf

        i = i + 1
    Wend


    CkRest::ckDispose(rest)
    CkStringBuilder::ckDispose(sbPath)
    CkXml::ckDispose(xml)
    CkStringBuilder::ckDispose(sbSaveFilePath)
    CkStringBuilder::ckDispose(sbAttachmentPath)
    CkBinData::ckDispose(attachmentData)


    ProcedureReturn
EndProcedure