(DataFlex) Download a File from a SharePoint Documents Library

See more SharePoint Examples

This example shows how to use Chilkat's HttpCurl class to download a file from the root of a SharePoint Documents document library. The example demonstrates how HttpCurl automatically resolves the SharePoint site name to a site ID, finds the drive ID for the Documents library, locates the file by name, and then downloads the file content using Microsoft Graph.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

Use ChilkatAx-win32.pkg

Procedure Test
    Boolean iSuccess
    Variant vJsonAuth
    Handle hoJsonAuth
    Handle hoCurl
    String sCurlCommand
    Integer iStatusCode
    Variant vSbFileContents
    Handle hoSbFileContents
    String sTemp1

    Move False To iSuccess

    // This example downloads a file named "hamlet.json" from the root of the SharePoint
    // Documents document library.
    // 
    // The example demonstrates how HttpCurl can automatically resolve all of the
    // information needed to locate and download a file:
    // 
    //   site_name            -> site_id
    //   site_id              -> document_library_id
    //   document_library_id  -> file_id
    //   file_id              -> file content
    // 
    // The application only provides the SharePoint site name and the desired
    // filename.  HttpCurl automatically executes the required Microsoft Graph
    // requests to obtain the remaining values.

    Move False To iSuccess

    // --------------------------------------------------------------------------------------------------------
    // Before running this example, create an Azure App Registration and grant it
    // the Microsoft Graph permissions required to access SharePoint.
    // 
    // The application will authenticate using OAuth2 Client Credentials.
    // See:
    // How to Create SharePoint App Registration for OAuth 2.0 Client Credentials
    // --------------------------------------------------------------------------------------------------------

    // Build a JSON authentication configuration.
    // HttpCurl will use this information to automatically obtain OAuth2 access tokens.
    Get Create (RefClass(cComChilkatJsonObject)) To hoJsonAuth
    If (Not(IsComObjectCreated(hoJsonAuth))) Begin
        Send CreateComObject of hoJsonAuth
    End

    // Enable secret lookup.
    // 
    // Instead of hard-coding sensitive values such as the client ID,
    // client secret, and token endpoint, secret specification strings
    // are used.  Chilkat automatically retrieves the actual values from
    // Windows Credential Manager (Windows) or Apple Keychain (macOS).
    // 
    // See:
    // Secret Specification Strings
    Set ComEnableSecrets Of hoJsonAuth To True

    Get ComUpdateString Of hoJsonAuth "oauth2.client_id" "!!sharepoint|oauth2|client_id" To iSuccess
    If (iSuccess = True) Begin
        Get ComUpdateString Of hoJsonAuth "oauth2.client_secret" "!!sharepoint|oauth2|client_secret" To iSuccess
    End

    If (iSuccess = True) Begin
        Get ComUpdateString Of hoJsonAuth "oauth2.token_endpoint" "!!sharepoint|oauth2|token_endpoint" To iSuccess
    End

    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoJsonAuth To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Request Microsoft Graph permissions that were granted to the application.
    Get ComUpdateString Of hoJsonAuth "oauth2.scope" "https://graph.microsoft.com/.default" To iSuccess

    // ---------------------------------------------------------------------------------------------------

    Get Create (RefClass(cComChilkatHttpCurl)) To hoCurl
    If (Not(IsComObjectCreated(hoCurl))) Begin
        Send CreateComObject of hoCurl
    End

    // Associate the OAuth2 configuration with HttpCurl.
    // 
    // When the request is executed, Chilkat automatically obtains an access token
    // if needed and adds the Authorization: Bearer header to the HTTP request.
    Get pvComObject of hoJsonAuth to vJsonAuth
    Get ComSetAuth Of hoCurl vJsonAuth To iSuccess

    // Define values that are already known.
    // 
    // These variables are referenced in curl commands using
    // {{variable_name}} substitution syntax.
    Send ComSetVar To hoCurl "sharepoint_hostname" "example.sharepoint.com"
    Send ComSetVar To hoCurl "site_name" "test"

    // The first step is to obtain the Microsoft Graph site ID.
    // 
    // The application only knows the SharePoint site name, so define
    // a function that can retrieve the site information.
    Get ComAddFunction Of hoCurl "getSite" "GET https://graph.microsoft.com/v1.0/sites/root:/sites/{{site_name}}" To iSuccess

    // Extract the site's ID and store it in the HttpCurl variable named site_id.
    Get ComAddOutput Of hoCurl "getSite" "id" "site_id" To iSuccess

    // The next step is to find the Documents document library.
    // 
    // Microsoft Graph refers to document libraries as "drives".
    Get ComAddFunction Of hoCurl "getDrives" "GET https://graph.microsoft.com/v1.0/sites/{{site_id}}/drives" To iSuccess

    // Search the returned drives for the one named "Documents"
    // and save its drive ID in the document_library_id variable.
    Get ComAddOutput2 Of hoCurl "getDrives" "value" "name" "Documents" True "id" "document_library_id" To iSuccess

    // Now list the contents of the Documents document library.
    Get ComAddFunction Of hoCurl "getFiles" "GET https://graph.microsoft.com/v1.0/sites/{{site_id}}/drives/{{document_library_id}}/root/children" To iSuccess

    // Search the returned files for an item named "hamlet.json"
    // and save its Microsoft Graph item ID in the file_id variable.
    Get ComAddOutput2 Of hoCurl "getFiles" "value" "name" "hamlet.json" True "id" "file_id" To iSuccess

    // This is the target request.
    // 
    // GET -L https://graph.microsoft.com/v1.0/drives/{{document_library_id}}/items/{{file_id}}/content
    // 
    // The /content endpoint returns the actual contents of the file.
    // 
    // The -L option instructs HttpCurl to follow the redirect returned by
    // Microsoft Graph.  The Graph API typically responds with a redirect
    // to the actual file download URL.
    Move "GET -L https://graph.microsoft.com/v1.0/drives/{{document_library_id}}/items/{{file_id}}/content" To sCurlCommand

    // Execute the request.
    // 
    // HttpCurl examines the target request and determines that both
    // document_library_id and file_id are required.
    // 
    // To obtain these values, it automatically builds and executes
    // the following dependency chain:
    // 
    //   1) getSite      -> site_id
    //   2) getDrives    -> document_library_id
    //   3) getFiles     -> file_id
    //   4) download     -> file content
    // 
    // The final response returned by DoYourThing is the downloaded
    // file content from the target request.
    Get ComDoYourThing Of hoCurl sCurlCommand To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoCurl To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // A successful Graph response should return HTTP 200.
    // Any other status code typically indicates an authentication,
    // permission, site lookup, document library lookup, or file lookup error.
    Get ComStatusCode Of hoCurl To iStatusCode
    If (iStatusCode <> 200) Begin
        Get ComResponseBodyStr Of hoCurl To sTemp1
        Showln sTemp1
        Showln "status code = " iStatusCode
        Procedure_Return
    End

    // The response body contains the contents of the downloaded file.
    Get Create (RefClass(cComChilkatStringBuilder)) To hoSbFileContents
    If (Not(IsComObjectCreated(hoSbFileContents))) Begin
        Send CreateComObject of hoSbFileContents
    End
    Get pvComObject of hoSbFileContents to vSbFileContents
    Get ComGetResponseSb Of hoCurl vSbFileContents To iSuccess

    // Optionally save the downloaded content to a local file.
    // 
    // The third argument controls whether the file is appended.
    // Passing ckfalse causes the file to be overwritten if it already exists.
    Get ComWriteFile Of hoSbFileContents "c:/temp/hamlet.json" "utf-8" False To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoSbFileContents To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Showln "Success."


End_Procedure