introduce AlmaLinux

AlmaLinux is an Open Source fork of Red Hat Enterprise Linux;
it should behave like a CentOS/RHEL.

cdist/conf/explorer/os

@@ -80,6 +80,12 @@ if [ -f /etc/owl-release ]; then
 fi
 
 ### Redhat and derivatives
+if grep -q ^AlmaLinux /etc/redhat-release 2>/dev/null
+then
+    echo almalinux
+    exit 0
+fi
+
 if grep -q ^Scientific /etc/redhat-release 2>/dev/null; then
     echo scientific
     exit 0

cdist/conf/explorer/os_version

@@ -125,7 +125,7 @@ in
    owl)
       cat /etc/owl-release
    ;;
-   redhat|centos|mitel|scientific)
+   almalinux|redhat|centos|mitel|scientific)
       cat /etc/redhat-release
    ;;
    slackware)

cdist/conf/type/__package/manifest

@@ -31,7 +31,7 @@ else
    # By default determine package manager based on operating system
    os="$(cat "$__global/explorer/os")"
    case "$os" in
-         amazon|scientific|centos|fedora|redhat) type="yum" ;;
+         almalinux|amazon|scientific|centos|fedora|redhat) type="yum" ;;
          archlinux) type="pacman" ;;
          debian|ubuntu|devuan) type="apt" ;;
          freebsd)

cdist/conf/type/__package_yum/gencode-remote

@@ -37,7 +37,7 @@ fi
 
 state_should="$(cat "$__object/parameter/state")"
 
-if grep -q -E "(scientific|centos|redhat|amazon)" "$__global/explorer/os"; then
+if grep -q -E "(almalinux|scientific|centos|redhat|amazon)" "$__global/explorer/os"; then
     opts="-y --quiet"
 else
     opts="--assumeyes --quiet"

cdist/conf/type/__yum_repo/manifest

@@ -22,7 +22,7 @@ os=$(cat "$__global/explorer/os")
 state="$(cat "$__object/parameter/state")"
 
 case "$os" in
-   scientific|centos)
+   almalinux|scientific|centos)
       repo_name="$__object_id"
       export repo_name
       repo_file="/etc/yum.repos.d/${repo_name}.repo"

docs/src/cdist-os.rst

@@ -3,6 +3,7 @@ Supported operating systems
 
 cdist was tested or is know to run on at least
 
+* `Alma Linux <https://https://almalinux.org>`_
 * `Alpine Linux <https://alpinelinux.org>`_
 * `Archlinux <http://www.archlinux.org>`_
 * `CentOS <http://www.centos.org>`_