Azure Function App Deployment via Azure DevOps Pipeline Fails with Invalid signature file digest or Cannot find any subscriptions Errors

Question

Azure Function App Deployment via Azure DevOps Pipeline Fails with Invalid signature file digest or Cannot find any subscriptions Errors

Abdelrhman Goma 115

🧵 Situation Summary

We are migrating part of our workload from an Azure Container App–based backend to Azure Function Apps as a cheaper, event-driven alternative for running a migration service (a Java project).

Our goal is to deploy a Java-based Azure Function (wallet-migration-function) using an Azure DevOps CI/CD pipeline. The Function App is currently using the App Service Plan: UKSouthLinuxDynamicPlan (Y1: 0), but we also considered using a Premium plan (container-based) depending on deployment stability and performance.

⚙️ Setup Details

🧱 Project

Java Function App built with Maven

Uses the azure-functions-maven-plugin version 1.18.0

Built as a JAR and deployed via mvn azure-functions:deploy

📦 POM Plugin Section

🧰 Azure DevOps Pipeline YAML

trigger:
- functionapp

pool:
  vmImage: 'ubuntu-latest'

variables:
  azureServiceConnection: 'p2p-v2-internal-sc-dev1'
  functionAppName: 'p2p-v2-migration-func-dev'
  resourceGroup: 'p2p-v2-internal-rg-dev'

# 1️⃣ Login to Azure
- task: AzureCLI@2
  displayName: 'Login to Azure (via Service Connection)'
  inputs:
    azureSubscription: $(azureServiceConnection)
    scriptType: bash
    scriptLocation: inlineScript
    inlineScript: |
      echo "✅ Logged in successfully."
      az account show

# 2️⃣ Build Function
- script: |
    mvn clean package -Dmaven.test.skip=true
  displayName: "Build Function"

# 3️⃣ Package Function
- script: |
    mvn azure-functions:package -Dmaven.test.skip=true
  displayName: "Stage Azure Function Package"

# 4️⃣ Deploy Function (Authenticated via Service Connection)
- task: AzureCLI@2
  displayName: 'Deploy Azure Function (authenticated via Service Connection)'
  inputs:
    azureSubscription: $(azureServiceConnection)
    scriptType: bash
    scriptLocation: inlineScript
    inlineScript: |
      mvn azure-functions:deploy -DauthType=azure_cli -DskipTests

# 5️⃣ Trigger Migration Run
- task: AzureCLI@2
  displayName: "Trigger Migration Run"
  inputs:
    azureSubscription: $(azureServiceConnection)
    scriptType: bash
    scriptLocation: inlineScript
    inlineScript: |
      FUNCTION_KEY=$(az functionapp function keys list \
        --resource-group $(resourceGroup) \
        --name $(functionAppName) \
        --function-name RunWalletMigrations \
        --query "default" -o tsv)
      curl -X POST "https://$(functionAppName).azurewebsites.net/api/RunWalletMigrations?code=$FUNCTION_KEY"

❌ Problem

The build and packaging stages succeed, but the deployment step fails with one of the following errors (depending on authentication type):

Error 1: Invalid Signature File Digest

[ERROR] Failed to execute goal com.microsoft.azure:azure-functions-maven-plugin:1.18.0:deploy (default-cli) 
on project wallet-migration-function: 
deploy to Azure Function App with resource creation or updating: Invalid signature file digest for Manifest main attributes

Error 2: Cannot Find Any Subscriptions

[ERROR] Failed to execute goal com.microsoft.azure:azure-functions-maven-plugin:1.18.0:deploy (default-cli) 
on project wallet-migration-function: 
deploy to Azure Function App with resource creation or updating: Cannot find any subscriptions in current account.

🧪 What We’ve Tried

✅ Using both:

az login before running mvn azure-functions:deploy

and deploying inside an AzureCLI@2 task (authenticated via service connection)

✅ Tested both authType=azure_cli and default authentication methods. ✅ Verified that the Azure service connection has Contributor rights on the resource group. ✅ Tried removing and recreating the Function App & Service Connection. ✅ Tried switching between Linux Consumption (Y1) and App Service Plan.

💡 Goal

We need guidance on:

Why azure-functions:deploy fails inside an Azure DevOps pipeline even after successful Azure login.

Whether using an App Service Plan (dedicated) or Function Premium (container-based) is the correct choice for a Java migration service that runs occasionally (triggered manually or on schedule).

How to make the deployment succeed reliably from CI/CD.

🗨️ Any Input Appreciated

We’d appreciate Microsoft’s input or any working sample for:

A Java Azure Function deployment from Azure DevOps using Maven

Best practice for authentication in CI/CD (service connection vs. azure_cli)

Recommended hosting plan for cost-effective, on-demand migration workloads

Abdelrhman Goma 115 Reputation points

2025-11-03T17:00:21.1966667+00:00

Hi Praveen Kumar Gudipudi
can you give me more details how can i do it please
Praveen Kumar Gudipudi 1,495 Reputation points Microsoft External Staff Moderator

2025-11-03T20:25:54.04+00:00

Hello Abdelrhman Goma,

Please follow below document for:

Using Azure DevOps Pipelines to Deploy Azure Functions written in Java.
Abdelrhman Goma 115 Reputation points

2025-11-04T14:04:25.25+00:00
Hi Praveen Kumar Gudipudi
I’ve followed the document you shared about using Azure DevOps Pipelines to deploy Azure Functions written in Java.

The pipeline itself now runs successfully, and the deployment completes without issues. However, I’m facing a runtime configuration problem in the Azure Portal after deployment.

Here are the details:

The Function App is configured for Java 17 and Azure Functions version 4.

In the Azure Portal → Configuration → General Settings, the Java version field is empty, and the runtime stack shows “Custom”.

The only available Java versions listed are 8 and 11, while our application specifically targets Java 17.

To align with the required Azure Functions v4 setup, I manually added a host.json file under src/main/resources with the following content:

{ "version": "2.0", "extensionBundle": { "id": "Microsoft.Azure.Functions.ExtensionBundle", "version": "[3.*, 4.0)" } }

Despite that, I still get the following runtime error in the portal logs:

Error code: AZFD0005 Message:

Error building configuration in an external startup class. Referenced bundle Microsoft.Azure.Functions.ExtensionBundle of version 1.8.1 does not meet the required minimum version of 2.6.1. Update your extension bundle reference in host.json to reference 2.6.1 or later. For more information see https://aka.ms/func-min-bundle-versions

Hit count: 21

It seems that even though the pipeline deploys correctly, the Function App runtime in Azure is not detecting the correct Java 17 environment and is falling back to an older extension bundle (1.8.1) instead of using the one defined in my host.json.

Could you please confirm if the Azure Function App runtime for Java 17 requires any specific configuration or environment setting to recognize the correct extension bundle version (≥ 2.6.1)?

Thank you,
Abdelrhman Goma
Praveen Kumar Gudipudi 1,495 Reputation points Microsoft External Staff Moderator

2025-11-04T14:36:51.3166667+00:00
Hello Abdelrhman Goma,

Thanks for the confirmation.

Update your host.json to specify the correct extension bundle version ([2.6.1, 4.0)).

2.Ensure the Java 17 runtime stack is selected in the Application Settings in Azure Portal.

{

"version": "2.0",

"extensionBundle": {

"id": "Microsoft.Azure.Functions.ExtensionBundle", "version": "[2.6.1, 4.0)" ``` } } Once the changes have been updated, please restart your function app.
Praveen Kumar Gudipudi 1,495 Reputation points Microsoft External Staff Moderator

2025-11-06T15:04:57.0266667+00:00

Hello Abdelrhman Goma,

We haven’t heard from you on the last response and was just checking back to see if you have a resolution yet. In case if you have any resolution please do share that same with the community as it can be helpful to others. Otherwise, will respond with more details and we will try to help.

Abdelrhman Goma 115

Hi Praveen Kumar Gudipudi
I'm facing another issue How can I properly pass the functionAppName from my Azure DevOps pipeline into the Maven build (without causing the recursive expression cycle)?

Should it be passed as a Maven parameter (e.g., -DfunctionAppName=$(functionAppName)) or defined differently in the pom.xml?
I’m deploying a Java-based Azure Function through an Azure DevOps pipeline, but the build keeps failing during the Maven package phase with this error:

[ERROR] Resolving expression: '${functionAppName}': Detected the following recursive expression cycle in 'functionAppName': [functionAppName]
[ERROR] The project com.webbats.p2p:wallet-migration-function:1.0.0 has 2 errors
[ERROR]     Resolving expression: '${functionAppName}': Detected the following recursive expression cycle in 'functionAppName': [functionAppName]

The full error output from the pipeline looks like this:

🧹 Cleaning and packaging Azure Function...
[INFO] Scanning for projects...
[ERROR] [ERROR] Some problems were encountered while processing the POMs:
[ERROR] Resolving expression: '${functionAppName}': Detected the following recursive expression cycle in 'functionAppName': [functionAppName]
[ERROR] The project com.webbats.p2p:wallet-migration-function:1.0.0 (/home/vsts/work/1/s/pom.xml) has 2 errors
[ERROR]     Resolving expression: '${functionAppName}': Detected the following recursive expression cycle in 'functionAppName': [functionAppName]

⚙️ Project Setup

This is a Java Azure Function project that I’m trying to build and package with Maven before deploying to Azure using the Azure CLI task in the pipeline.

Here’s the relevant section from my pom.xml:

<project>
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.webbats.p2p</groupId>
  <artifactId>wallet-migration-function</artifactId>
  <version>1.0.0</version>
  <packaging>jar</packaging>

  <properties>
    <functionAppName>${functionAppName}</functionAppName>
    <functionAppRegion>uksouth</functionAppRegion>
    <functionAppResourceGroup>p2p-v2-rg-internal</functionAppResourceGroup>
  </properties>

  <build>
    <plugins>
      <plugin>
        <groupId>com.microsoft.azure</groupId>
        <artifactId>azure-functions-maven-plugin</artifactId>
        <version>1.22.0</version>
        <configuration>
          <resourceGroup>${functionAppResourceGroup}</resourceGroup>
          <appName>${functionAppName}</appName>
          <region>${functionAppRegion}</region>
          <pricingTier>Consumption</pricingTier>
        </configuration>
      </plugin>
    </plugins>
  </build>
</project>

🧩 Pipeline YAML

Here’s the Azure DevOps pipeline YAML used to build and deploy the Function:

trigger:
- main

pool:
  vmImage: 'ubuntu-latest'

variables:
  azureSubscription: 'P2P-Internal-Connection'
  functionAppName: 'p2p-v2-migration-func-dev'
  functionAppRG: 'p2p-v2-rg-internal'
  javaVersion: '17'
  artifactName: 'drop'

steps:
- task: Maven@3
  displayName: 'Build Azure Function'
  inputs:
    mavenPomFile: 'pom.xml'
    goals: 'clean package'
    javaHomeOption: 'JDKVersion'
    jdkVersionOption: '1.17'
    publishJUnitResults: false
    options: '-X'

- task: AzureCLI@2
  displayName: 'Deploy Function to Azure'
  inputs:
    azureSubscription: '$(azureSubscription)'
    scriptType: 'bash'
    scriptLocation: 'inlineScript'
    inlineScript: |
      echo "🚀 Searching for ZIP artifact..."
      ls -R target
      ZIP_FILE=$(find target/azure-functions -name "*.zip" | head -n 1)
      if [ -z "$ZIP_FILE" ]; then
        echo "❌ No ZIP file found. Expected something like: target/azure-functions/${functionAppName}/${functionAppName}.zip"
        exit 1
      fi
      az functionapp deployment source config-zip \
        --resource-group $(functionAppRG) \
        --name $(functionAppName) \
        --src "$ZIP_FILE"

🧠 What I’ve Tried

Confirmed that ${functionAppName} is set in both the pipeline variables and the POM file.

Tried defining <functionAppName> directly in the POM instead of using ${functionAppName} → the build works locally when hardcoded.

Tried passing -DfunctionAppName=$(functionAppName) in the Maven task options.

Verified that the pipeline is correctly using the service principal and subscription — login works fine.

🚨 Current Issue

The Maven build fails before packaging because the ${functionAppName} property references itself in the POM, causing a recursive expression cycle. However, I want to inject the Function App name dynamically from the pipeline instead of hardcoding it.

Praveen Kumar Gudipudi 1,495 Reputation points Microsoft External Staff Moderator

2025-11-06T19:01:37.4066667+00:00

Hello Abdelrhman Goma,

You're hitting the recursive cycle because the POM defines:

<``properties>

<``functionAppName>${functionAppName}</functionAppName>

</``properties>

That line makes the property reference itself, so when Maven tries to resolve ${functionAppName}, it loops forever and throws the cycle error.

don’t define functionAppName as ${functionAppName} in the POM. Instead, supply it from your pipeline (or an environment variable), and let the Azure Functions Maven plugin read it.

Please accept as answer and do a Thumbs-up to upvote this response if you are satisfied with the community help. Your upvote will be beneficial for the community users facing similar issues.

1 answer

Your answer

Abdelrhman Goma 115 Reputation points

2025-11-03T17:00:21.1966667+00:00

Hi Praveen Kumar Gudipudi
can you give me more details how can i do it please
Praveen Kumar Gudipudi 1,495 Reputation points Microsoft External Staff Moderator

2025-11-03T20:25:54.04+00:00

Hello Abdelrhman Goma,

Please follow below document for:

Using Azure DevOps Pipelines to Deploy Azure Functions written in Java.
Abdelrhman Goma 115 Reputation points

2025-11-04T14:04:25.25+00:00

Hi Praveen Kumar Gudipudi
I’ve followed the document you shared about using Azure DevOps Pipelines to deploy Azure Functions written in Java.

The pipeline itself now runs successfully, and the deployment completes without issues. However, I’m facing a runtime configuration problem in the Azure Portal after deployment.

Here are the details:

The Function App is configured for Java 17 and Azure Functions version 4.

In the Azure Portal → Configuration → General Settings, the Java version field is empty, and the runtime stack shows “Custom”.

The only available Java versions listed are 8 and 11, while our application specifically targets Java 17.

To align with the required Azure Functions v4 setup, I manually added a host.json file under src/main/resources with the following content:

{ "version": "2.0", "extensionBundle": { "id": "Microsoft.Azure.Functions.ExtensionBundle", "version": "[3.*, 4.0)" } }

Despite that, I still get the following runtime error in the portal logs:

Error code: AZFD0005 Message:

Error building configuration in an external startup class. Referenced bundle Microsoft.Azure.Functions.ExtensionBundle of version 1.8.1 does not meet the required minimum version of 2.6.1. Update your extension bundle reference in host.json to reference 2.6.1 or later. For more information see https://aka.ms/func-min-bundle-versions

Hit count: 21

It seems that even though the pipeline deploys correctly, the Function App runtime in Azure is not detecting the correct Java 17 environment and is falling back to an older extension bundle (1.8.1) instead of using the one defined in my host.json.

Could you please confirm if the Azure Function App runtime for Java 17 requires any specific configuration or environment setting to recognize the correct extension bundle version (≥ 2.6.1)?

Thank you,
Abdelrhman Goma
Praveen Kumar Gudipudi 1,495 Reputation points Microsoft External Staff Moderator

2025-11-04T14:36:51.3166667+00:00

Hello Abdelrhman Goma,

Thanks for the confirmation.

Update your host.json to specify the correct extension bundle version ([2.6.1, 4.0)).

2.Ensure the Java 17 runtime stack is selected in the Application Settings in Azure Portal.

{

"version": "2.0",

"extensionBundle": {

"id": "Microsoft.Azure.Functions.ExtensionBundle", "version": "[2.6.1, 4.0)" ``` } } Once the changes have been updated, please restart your function app.
Praveen Kumar Gudipudi 1,495 Reputation points Microsoft External Staff Moderator

2025-11-06T15:04:57.0266667+00:00

Hello Abdelrhman Goma,

We haven’t heard from you on the last response and was just checking back to see if you have a resolution yet. In case if you have any resolution please do share that same with the community as it can be helpful to others. Otherwise, will respond with more details and we will try to help.
Praveen Kumar Gudipudi 1,495 Reputation points Microsoft External Staff Moderator

2025-11-06T19:01:37.4066667+00:00

Hello Abdelrhman Goma,

You're hitting the recursive cycle because the POM defines:

<``properties>

<``functionAppName>${functionAppName}</functionAppName>

</``properties>

That line makes the property reference itself, so when Maven tries to resolve ${functionAppName}, it loops forever and throws the cycle error.

don’t define functionAppName as ${functionAppName} in the POM. Instead, supply it from your pipeline (or an environment variable), and let the Azure Functions Maven plugin read it.

Please accept as answer and do a Thumbs-up to upvote this response if you are satisfied with the community help. Your upvote will be beneficial for the community users facing similar issues.

Answer 1

Hello Abdelrhman Goma,

You're hitting the recursive cycle because the POM defines:

<``properties>

<``functionAppName>${functionAppName}</functionAppName>

</``properties>

That line makes the property reference itself, so when Maven tries to resolve ${functionAppName}, it loops forever and throws the cycle error.

don’t define functionAppName as ${functionAppName} in the POM. Instead, supply it from your pipeline (or an environment variable), and let the Azure Functions Maven plugin read it.

Please accept as answer and do a Thumbs-up to upvote this response if you are satisfied with the community help. Your upvote will be beneficial for the community users facing similar issues.

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Azure Function App Deployment via Azure DevOps Pipeline Fails with Invalid signature file digest or Cannot find any subscriptions Errors

🧵 Situation Summary

⚙️ Setup Details

🧱 Project

📦 POM Plugin Section

🧰 Azure DevOps Pipeline YAML

❌ Problem

Error 1: Invalid Signature File Digest

Error 2: Cannot Find Any Subscriptions

🧪 What We’ve Tried

💡 Goal

🗨️ Any Input Appreciated

⚙️ Project Setup

🧩 Pipeline YAML

🧠 What I’ve Tried

🚨 Current Issue

1 answer

Your answer