ci : improve mirror handling github workflow

This commit contains changes to build.yml to enhance the robustness of
apt package installation by implementing retries and fallback
mechanisms when accessing Ubuntu package mirrors.

Author: danbev

.github/workflows/build.yml

@@ -56,6 +56,53 @@ env:
   BRANCH_NAME: ${{ github.head_ref || github.ref_name }}
   ubuntu_image: "ubuntu:22.04"
   VCPKG_BINARY_SOURCES: "clear;x-gha,readwrite"
+  # Reusable shell function for robust apt setup
+  SETUP_APT_FUNCTION: |
+    setup_robust_apt() {
+        set -e
+        export DEBIAN_FRONTEND=noninteractive
+
+        # Configure apt retry logic and timeouts
+        echo "Acquire::Retries \"3\";" > /etc/apt/apt.conf.d/80-retries
+        echo "Acquire::http::Timeout \"10\";" > /etc/apt/apt.conf.d/80-timeout
+        echo "Acquire::https::Timeout \"10\";" >> /etc/apt/apt.conf.d/80-timeout
+
+        # Try multiple mirrors with fallback
+        for mirror in "mirrors.kernel.org" "mirror.pit.teraswitch.com" "archive.ubuntu.com"; do
+            echo "Trying mirror: $mirror"
+            sed -i "s|archive.ubuntu.com|$mirror|g" /etc/apt/sources.list
+            sed -i "s|security.ubuntu.com|$mirror|g" /etc/apt/sources.list
+            if apt-get update; then
+                echo "Successfully using mirror: $mirror"
+                break
+            else
+                echo "Mirror $mirror failed, trying next..."
+                sed -i "s|$mirror|archive.ubuntu.com|g" /etc/apt/sources.list
+            fi
+        done
+
+        apt-get install -y ca-certificates
+
+        # For ARM architectures, try multiple port mirrors with fallback
+        if echo "${1:-}" | grep -q "arm"; then
+            for port_mirror in "mirrors.kernel.org" "mirror.pit.teraswitch.com" "ports.ubuntu.com"; do
+                if [ "$port_mirror" = "ports.ubuntu.com" ]; then
+                    port_mirror_url="http://$port_mirror"
+                else
+                    port_mirror_url="http://$port_mirror"
+                fi
+                echo "Trying ports mirror: $port_mirror_url"
+                sed -i "s|http://ports.ubuntu.com|$port_mirror_url|g" /etc/apt/sources.list
+                if apt-get update; then
+                    echo "Successfully using ports mirror: $port_mirror_url"
+                    break
+                else
+                    echo "Ports mirror $port_mirror_url failed, trying next..."
+                    sed -i "s|$port_mirror_url|http://ports.ubuntu.com|g" /etc/apt/sources.list
+                fi
+            done
+        fi
+    }
 
 jobs:
   determine-tag:
@@ -136,12 +183,13 @@ jobs:
           docker run --platform ${{ matrix.arch }} --rm \
             -v ${{ github.workspace }}:/workspace \
             -w /workspace ${{ env.ubuntu_image }} /bin/sh -c '
-            set -e
-            export DEBIAN_FRONTEND=noninteractive
-            sed -i "s|archive.ubuntu.com|mirrors.kernel.org|g" /etc/apt/sources.list
-            sed -i "s|security.ubuntu.com|mirrors.kernel.org|g" /etc/apt/sources.list
+            # Source the robust apt setup function
+            eval "${{ env.SETUP_APT_FUNCTION }}"
 
-            apt update
+            # Setup apt with robust mirror handling
+            setup_robust_apt "${{ matrix.arch }}"
+
+            # Install packages and build
             apt install -y build-essential libsdl2-dev cmake git
             cmake -B build
             cmake --build build --config Release -j $(nproc)'
@@ -168,16 +216,13 @@ jobs:
           docker run --platform ${{ matrix.arch }} --rm \
             -v ${{ github.workspace }}:/workspace \
             -w /workspace ${{ env.ubuntu_image }} /bin/sh -c '
-            set -e
-            export DEBIAN_FRONTEND=noninteractive
-            sed -i "s|archive.ubuntu.com|mirrors.kernel.org|g" /etc/apt/sources.list
-            sed -i "s|security.ubuntu.com|mirrors.kernel.org|g" /etc/apt/sources.list
+            # Source the robust apt setup function
+            eval "${{ env.SETUP_APT_FUNCTION }}"
 
-            apt-get update
-            apt-get install -y ca-certificates
-            sed -i "s|http://ports.ubuntu.com|https://mirror.kumi.systems|g" /etc/apt/sources.list
+            # Setup apt with robust mirror handling
+            setup_robust_apt "${{ matrix.arch }}"
 
-            apt update
+            # Install packages and build
             apt install -y build-essential libsdl2-dev cmake git
             cmake -B build -DGGML_NATIVE=OFF -DGGML_CPU_ARM_ARCH=armv8-a
             cmake --build build --config Release -j $(nproc)'
@@ -204,16 +249,13 @@ jobs:
           docker run --platform ${{ matrix.arch }} --rm \
             -v ${{ github.workspace }}:/workspace \
             -w /workspace ${{ env.ubuntu_image }} /bin/sh -c '
-            set -e
-            export DEBIAN_FRONTEND=noninteractive
-            sed -i "s|archive.ubuntu.com|mirrors.kernel.org|g" /etc/apt/sources.list
-            sed -i "s|security.ubuntu.com|mirrors.kernel.org|g" /etc/apt/sources.list
+            # Source the robust apt setup function
+            eval "${{ env.SETUP_APT_FUNCTION }}"
 
-            apt-get update
-            apt-get install -y ca-certificates
-            sed -i "s|http://ports.ubuntu.com|https://mirror.kumi.systems|g" /etc/apt/sources.list
+            # Setup apt with robust mirror handling
+            setup_robust_apt "${{ matrix.arch }}"
 
-            apt update
+            # Install packages and build
             apt install -y build-essential libsdl2-dev cmake git
             cmake -B build -DGGML_NATIVE=OFF -DGGML_CPU_ARM_ARCH=armv7-a+fp
             cmake --build build --config Release -j $(nproc)'
@@ -411,16 +453,13 @@ jobs:
           docker run --platform ${{ matrix.arch }} --rm \
             -v ${{ github.workspace }}:/workspace \
             -w /workspace ${{ env.ubuntu_image }} /bin/sh -c '
-            set -e
-            export DEBIAN_FRONTEND=noninteractive
-            sed -i "s|archive.ubuntu.com|mirrors.kernel.org|g" /etc/apt/sources.list
-            sed -i "s|security.ubuntu.com|mirrors.kernel.org|g" /etc/apt/sources.list
+            # Source the robust apt setup function
+            eval "${{ env.SETUP_APT_FUNCTION }}"
 
-            apt-get update
-            apt-get install -y ca-certificates
-            sed -i "s|http://ports.ubuntu.com|https://mirror.kumi.systems|g" /etc/apt/sources.list
+            # Setup apt with robust mirror handling
+            setup_robust_apt "${{ matrix.arch }}"
 
-            apt update
+            # Install packages and build
             apt install -y clang build-essential cmake libsdl2-dev git
             cmake . -DWHISPER_SDL2=ON -DCMAKE_BUILD_TYPE=${{ matrix.build }} -DCMAKE_CXX_COMPILER=clang++ -DCMAKE_C_COMPILER=clang
             make
@@ -449,12 +488,13 @@ jobs:
           docker run --platform ${{ matrix.arch }} --rm \
             -v ${{ github.workspace }}:/workspace \
             -w /workspace ${{ env.ubuntu_image }} /bin/sh -c '
-            set -e
-            export DEBIAN_FRONTEND=noninteractive
-            sed -i "s|archive.ubuntu.com|mirrors.kernel.org|g" /etc/apt/sources.list
-            sed -i "s|security.ubuntu.com|mirrors.kernel.org|g" /etc/apt/sources.list
+            # Source the robust apt setup function
+            eval "${{ env.SETUP_APT_FUNCTION }}"
 
-            apt update
+            # Setup apt with robust mirror handling
+            setup_robust_apt "${{ matrix.arch }}"
+
+            # Install packages and build
             apt install -y build-essential cmake git
             cmake . -DCMAKE_BUILD_TYPE=Debug \
               -DWHISPER_SANITIZE_${{ matrix.sanitizer }}=ON \