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ford_sopris's avatar
ford_sopris
Copper Contributor
Jul 19, 2022

Azure Function to unzip blob to specific blob folder

If this is not the right group to post this, please let me know.  I am not much of a developer but have a need to extract a ZIP file that resides in a Blob Container into the same container in a specific folder, I would like that folder to be named the same of the zip filename.  I have found several Azure Function blobs that use the new file blob trigger but all of them simply extract all the files in a specific container.  I cannot for the life of me figure out how to tell it to save it in a specific folder and how to get it to pull the name of the file to name that folder.  Does anyone have a template or code they would be willing to share with me?  The reason I need this is due to the fact that Power Automate's "extract to ***" connectors have a limit of 100 files in the zip.  Of course my zip files have just over 100 files in them......

Compute

1 Reply

  • Kidd_Ip's avatar
    Kidd_Ip
    MVP
    Oct 17, 2025

    Try Azure Function Code (C#)

     

    using System.IO;
using System.IO.Compression;
using Microsoft.Azure.WebJobs;
using Microsoft.Extensions.Logging;
using Azure.Storage.Blobs;
using Azure.Storage.Blobs.Specialized;

public static class UnzipBlobFunction
{
    [FunctionName("UnzipBlobFunction")]
    public static async Task Run(
        [BlobTrigger("input-container/{name}", Connection = "AzureWebJobsStorage")] Stream zipBlob,
        string name,
        ILogger log)
    {
        string zipFileNameWithoutExtension = Path.GetFileNameWithoutExtension(name);
        string outputContainerName = "input-container"; // same container

        var blobServiceClient = new BlobServiceClient(Environment.GetEnvironmentVariable("AzureWebJobsStorage"));
        var containerClient = blobServiceClient.GetBlobContainerClient(outputContainerName);

        using (var archive = new ZipArchive(zipBlob))
        {
            foreach (var entry in archive.Entries)
            {
                if (string.IsNullOrEmpty(entry.Name)) continue; // skip folders

                string outputBlobPath = $"{zipFileNameWithoutExtension}/{entry.Name}";
                var outputBlobClient = containerClient.GetBlobClient(outputBlobPath);

                using (var entryStream = entry.Open())
                using (var memoryStream = new MemoryStream())
                {
                    await entryStream.CopyToAsync(memoryStream);
                    memoryStream.Position = 0;
                    await outputBlobClient.UploadAsync(memoryStream, overwrite: true);
                }

                log.LogInformation($"Extracted: {outputBlobPath}");
            }
        }
    }
}

     

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