Azure Functions
Backend & InfraThe host/runtime that powers Azure Functions
Release History
View all versions →v4.1054.2001 fixThis release addresses an issue where Linux language worker SIGTERM exits were incorrectly reported as worker failures.
v4.1054.1002 fixesUpdated PowerShell workers to latest versions and improved gRPC server availability and authorization cache handling.
v4.1053.1006 fixesThis release addresses several race conditions and leaks in worker channel shutdown and specialization, improving host stability and log flushing. It also includes updates to various language workers and middleware.
v4.852.100This is a placeholder for release notes. Please add your release notes in the specified format.
v4.652.100This is a placeholder for release notes. Please add your release notes in the specified format.
v4.1052.200This release updates the underlying Python Worker version to 4.45.1, primarily addressing internal dependencies or minor stability improvements.
v4.1052.1005 fixes1 featureThis release focuses on stability and security, fixing races during config reload, preventing early secret manager access during health checks, and ensuring proper process count configuration on high-core machines.
v4.1051.300This release appears to be a placeholder or empty release, as no specific changes were documented in the provided notes.
v4.1051.2002 fixesThis release focuses on stability by fixing a race condition in configuration reloading and ensuring health checks do not interfere with secret manager initialization.
v4.1048.3002 fixesThis release focuses on stability by fixing a concurrent read/write race condition during config reloads and preventing premature secret manager access during health checks.
v4.851.1001 fixThis release primarily consists of an update to the Java Worker version to 2.19.4.
v4.651.1001 fixThis release primarily consists of an update to the Java Worker version to 2.19.4.
v4.1051.100Breaking6 fixes1 featureThis release restores Logic App worker discovery, fixes several environment and configuration handling bugs, and addresses a breaking change related to connection string environment variables in .NET 10.
v4.1050.1001 featureThis release introduces support for querying application capabilities via new admin endpoints, aggregating information from various sources like language workers and host configuration.
v4.1049.2001 fix1 featureThis release updates logging for TimerTriggerPlatformOptions and ensures WebHostWorkerRuntimeResolver correctly reads configuration values for FWR.
v4.1049.100Breaking1 fix1 featureThis release introduces a refactoring for worker runtime resolution and fixes a bug related to custom handlers and extension bundles, while migrating the underlying runtime to .NET 10.
v4.849.100This release introduces a bundle version cap for net8 in-proc environments.
v4.649.100This release introduces a bundle version cap for net8 in-proc environments.
webjobs-script-abstractions-v1.1.01 featureThe Microsoft.Azure.WebJobs.Script.Abstractions package introduced AppCapabilitiesOptions to enable reporting of app capabilities to the host.
webjobs-script-abstractions-v1.0.4Version 1.0.4 of Microsoft.Azure.WebJobs.Script.Abstractions contains no changes from the preceding 1.0.4-preview release.
v4.1048.2001 fixThis minor release addresses a specific bug related to loading binding types in custom handler apps utilizing extension bundles.
v4.1048.1003 fixes3 featuresThis release introduces support for propagating worker tags to the host, adds PowerShell 7.6 support, and improves resiliency and configuration handling across various components.
v4.848.1001 featureThis release introduces configurable WorkingDirectory support for language worker processes.
v4.1047.1002 fixes2 featuresThis release focuses on enhancing observability by adding OTEL environment variable support and improving health check diagnostics, alongside updating underlying language worker versions.
v4.1046.1001 fix4 featuresThis release introduces a new "web app" configuration profile and enhances health checks by adding the AzureWebJobsStorage check and ErrorCode telemetry. A bug affecting webPubSubTrigger on Flex consumption SKUs has also been resolved.
Common Errors
InvalidOperationException6 reportsInvalidOperationException in Azure Functions often stems from concurrency issues during initialization of singleton clients like BlobServiceClient or language workers. To fix it, ensure proper locking mechanisms or lazy initialization patterns are used for singleton objects, and verify your FUNCTIONS_WORKER_RUNTIME setting is correctly configured and that the associated language worker is properly installed to avoid worker initialization failures. Reducing the complexity of startup logic and dependencies can also help prevent race conditions.
ObjectDisposedException5 reportsObjectDisposedException in Azure Functions often arises from accessing services or objects after the function host has been recycled or shut down. Resolve this by ensuring all service scopes are properly managed and disposed of within the function's execution context. Avoid storing dependencies obtained from IServiceProvider as static or long-lived objects, and leverage dependency injection scopes ("using" statements or IDisposable pattern) to guarantee resource disposal after use.
InternalServerError4 reports"InternalServerError" in Azure Functions often indicates a problem within the Azure infrastructure or the function app's configuration, preventing successful execution. To fix it: Review your function app's configuration, ensuring key vault references, managed identities, and dependencies are correctly configured and accessible. If the issue persists, check the Azure status page for any service outages and consider restarting the function app or redeploying to force a refresh of the environment.
FunctionInvocationException4 reportsFunctionInvocationException in Azure Functions commonly arises from unhandled exceptions within your function code or incompatibilities between the host and function dependencies. Ensure robust error handling with try-catch blocks in your function, and verify that your function app's dependencies are compatible with the Azure Functions runtime version you're using. Review the function execution logs in Azure Monitor for detailed stack traces to pinpoint the root cause and address it directly within your function code or deployment configuration.
HandleWorkerStartStreamError3 reportsThe "HandleWorkerStartStreamError" error usually indicates a problem establishing the gRPC stream between the Azure Functions host and the language worker, often due to network issues, worker process crashes, or misconfiguration. Fix this by ensuring the worker process is correctly installed and configured, that there are no firewall or network restrictions preventing communication, and inspecting worker logs for specific error details hindering stream establishment. Additionally, verify compatibility between the Azure Functions host version and the language worker version.
HttpRequestException3 reportsHttpRequestException in Azure Functions commonly arises from network connectivity issues, DNS resolution failures, or problems reaching the intended endpoint. To resolve this, ensure your function app has proper outbound network access (e.g., configure outbound IPs or VNet integration), verify DNS settings, and confirm that the target service is reachable and responsive. Check firewall rules on both the function app and the target service, and consider using Application Insights to diagnose network-related errors.
Related Backend & Infra Packages
Production-Grade Container Scheduling and Management
Node.js JavaScript runtime ✨🐢🚀✨
Promise based HTTP client for the browser and node.js
A modern runtime for JavaScript and TypeScript.
Deliver web apps with confidence 🚀
Incredibly fast JavaScript runtime, bundler, test runner, and package manager – all in one
Subscribe to Updates
Get notified when new versions are released