Upload Large Files via Azure App Gateway and Azure APIM to Azure Storage: A Step-by-Step Guide

Are you tired of struggling with large file uploads to Azure Storage? Do you want to leverage the power of Azure App Gateway and Azure APIM to streamline your file upload process? Look no further! In this comprehensive guide, we’ll walk you through the step-by-step process of uploading large files via Azure App Gateway and Azure APIM to Azure Storage.

Prerequisites

Before we dive into the tutorial, make sure you have the following prerequisites in place:

• Azure Subscription
• Azure Storage Account
• Azure App Gateway instance
• Azure APIM instance
• A basic understanding of Azure services and APIs

Step 1: Configure Azure App Gateway

Azure App Gateway is a web application firewall that provides a scalable and secure way to deliver web applications. To configure Azure App Gateway for large file uploads, follow these steps:

1. Log in to the Azure portal and navigate to your App Gateway instance.
2. Click on the “Configuration” tab and scroll down to the “HTTP settings” section.
3. Click on the “Edit” button next to “HTTP settings.”
4. In the “HTTP settings” blade, set the “Request body size limit” to a suitable value (e.g., 2048 MB).
5. Save the changes.

Note: The request body size limit determines the maximum size of the file that can be uploaded. Make sure to set it to a value that accommodates your large files.

Step 2: Configure Azure APIM

Azure APIM is a fully managed API management service that enables you to create, manage, and secure APIs. To configure Azure APIM for large file uploads, follow these steps:

1. Log in to the Azure portal and navigate to your APIM instance.
2. Click on the “APIs” tab and select the API that you want to use for large file uploads.
3. Click on the “Settings” tab and scroll down to the “Request” section.
4. In the “Request” section, set the “Request body size limit” to a suitable value (e.g., 2048 MB).
5. Save the changes.

Note: The request body size limit in APIM should match the value set in App Gateway.

Step 3: Create an API in Azure APIM

Create a new API in Azure APIM that will handle large file uploads:

1. In the Azure portal, navigate to your APIM instance.
2. Click on the “APIs” tab and click the “New API” button.
3. Enter a name and description for your API.
4. Select “REST” as the API type.
5. In the “API URL suffix” field, enter a unique suffix (e.g., “largefileupload”).
6. Click “Create” to create the API.

Step 4: Add an Operation to the API

Add an operation to the API that will handle large file uploads:

1. In the Azure portal, navigate to your APIM instance.
2. Click on the “APIs” tab and select the API you created in Step 3.
3. Click on the “Operations” tab and click the “New operation” button.
4. Enter a name and description for the operation.
5. Select “POST” as the HTTP method.
6. In the “Request body” section, select “File” as the request body type.
7. Click “Save” to save the operation.

Step 5: Configure Azure Storage

Configure Azure Storage to store the large files uploaded via the API:

1. In the Azure portal, navigate to your Storage Account.
2. Click on the “Containers” tab and click the “New container” button.
3. Enter a name for the container (e.g., “largefiles”).
4. Set the “Public access level” to “Blob (anonymous read access for blobs only)”.
5. Click “Create” to create the container.

Step 6: Implement the Upload Logic

Implement the upload logic in your API using Azure APIM policies:

1. In the Azure portal, navigate to your APIM instance.
2. Click on the “APIs” tab and select the API you created in Step 3.
3. Click on the “Policies” tab and click the “New policy” button.
4. Select “Import policy” and import the following policy:

<policy>
    <inbound>
        <base></base>
        <set-variable name="file" value="@(context.Request.Body.As<string>())" />
        <set-variable name="storageConnectionString" value="DefaultEndpointsProtocol=https;AccountName=[YourStorageAccount];AccountKey=[YourStorageKey];BlobEndpoint=[YourStorageBlobEndpoint]" />
        <set-variable name="containerName" value="largefiles" />
        <set-variable name="blobName" value="@Guid.NewGuid().ToString()" />
        <set-variable name="blob" value="@{
            var blockBlob = new CloudBlockBlob(new Uri($"https://{storageConnectionString.AccountName}.blob.core.windows.net/{containerName}/{blobName}"), new StorageCredentials(storageConnectionString.AccountName, storageConnectionString.AccountKey));
            blockBlob.UploadFromStreamAsync(file).GetAwaiter().GetResult();
            return blockBlob;
        }" />
    </inbound>
    <outbound>
        <base></base>
        <return-response>
            <set-status code="201" />
            <set-body>@{
                return new JObject(
                    new JProperty("blobUrl", blob.Uri.AbsoluteUri)
                );
            }</set-body>
        </return-response>
    </outbound>
</policy>

Note: Replace [YourStorageAccount], [YourStorageKey], and [YourStorageBlobEndpoint] with your actual Azure Storage account credentials.

Step 7: Test the API

Test the API using a tool like Postman or cURL:

1. Send a POST request to the API endpoint (e.g., `https://yourapim.azure-api.net/largefileupload`).
2. In the request body, include the large file you want to upload.
3. Verify that the API returns a 201 response with the URL of the uploaded blob.

API Endpoint	Request Body	Response
https://yourapim.azure-api.net/largefileupload	Large file (e.g., 1 GB)	201 Created https://yourstorage.blob.core.windows.net/largefiles/[guid].blob

Conclusion

And that’s it! You’ve successfully configured Azure App Gateway and Azure APIM to upload large files to Azure Storage. This setup provides a scalable and secure way to handle large file uploads, and can be easily integrated with your existing applications.

Remember to test your API thoroughly and adjust the configuration as needed to meet your specific requirements.

Additional Resources

• Azure App Gateway documentation:
• Azure APIM documentation:
• Azure Storage documentation:

Happy uploading!

Frequently Asked Question

Got questions about uploading large files via Azure App Gateway and Azure APIM to Azure Storage? We’ve got you covered!