Add plugin support to install prometheus-podman-exporter

It will help us to enable multiple exporters on single node.

Change-Id: I2509367e4d92af4f63e461390d8de822a4598d32
Signed-off-by: Chandan Kumar (raukadah) <chkumar@redhat.com>

.zuul.yaml

@@ -26,6 +26,7 @@
       devstack_services:
         prometheus: true
         node_exporter: true
+        podman_exporter: true
       zuul_copy_output:
         /etc/prometheus/prometheus.yml: logs
 

devstack/files/prometheus.yml

@@ -4,6 +4,7 @@ global:
 scrape_configs:
   - job_name: "node"
     static_configs:
+      - targets: ["localhost:9882"]
       - targets: ["localhost:9100"] # node_exporter target
 #        labels:
 #          fqdn: "controller" # node_exporter fqdn

devstack/lib/podman_exporter

@@ -0,0 +1,82 @@
+# lib/podman_exporter
+# Functions to control the installation and configuration of podman_exporter
+
+# Save trace setting
+_XTRACE_PODMAN_EXPORTER=$(set +o | grep xtrace)
+set +o xtrace
+
+PODMAN_EXPORTER_BINARY="/usr/local/bin/prometheus-podman-exporter"
+PODMAN_EXPORTER_SYSTEMD_SERVICE="devstack@podman-exporter.service"
+PODMAN_EXPORTER_PORT=${PODMAN_EXPORTER_PORT:-9882}
+PE_REPO=${PE_REPO:-https://github.com/containers/prometheus-podman-exporter.git}
+PE_REPO_NAME=${PE_REPO_NAME:-prometheus-podman-exporter}
+
+function pre_install_podman_exporter {
+    # Install OS packages
+    install_package libgpgme-dev libassuan-dev libbtrfs-dev libdevmapper-dev pkg-config build-essential golang podman uidmap netavark
+}
+
+function install_podman_exporter {
+
+    # Clone prometheus-podman-exporter
+    PE_DIR=$DEST/$PE_REPO_NAME
+    git_timed clone $PE_REPO $PE_DIR
+
+    # Generate Binary
+    cd $PE_DIR
+    make binary
+
+    # Move binaries to /usr/local/bin
+    sudo mv $PE_DIR/bin/prometheus-podman-exporter /usr/local/bin/
+
+    # Set ownership
+    sudo chown $(whoami):$(whoami) ${NODE_EXPORTER_BINARY}
+}
+
+function init_podman_exporter {
+
+    podman_exporter_cmd=${PODMAN_EXPORTER_BINARY}
+    podman_exporter_cmd+=" --collector.enable-all"
+
+    write_user_unit_file $PODMAN_EXPORTER_SYSTEMD_SERVICE "$podman_exporter_cmd" "" "$STACK_USER"
+
+    enable_service $PODMAN_EXPORTER_SYSTEMD_SERVICE
+}
+
+function start_podman_exporter {
+    start_service $PODMAN_EXPORTER_SYSTEMD_SERVICE
+}
+
+function stop_podman_exporter {
+    stop_service $PODMAN_EXPORTER_SYSTEMD_SERVICE
+}
+
+function cleanup_podman_exporter {
+    stop_podman_exporter
+    disable_service $PODMAN_EXPORTER_SYSTEMD_SERVICE
+
+    # Remove systemd unit files
+    local unitfile="$SYSTEMD_DIR/$PODMAN_EXPORTER_SYSTEMD_SERVICE"
+    sudo rm -f $unitfile
+    $SYSTEMCTL daemon-reload
+
+    # Remove Node Exporter binaries
+    sudo rm -rf $PODMAN_EXPORTER_BINARY
+}
+
+function wait_for_podman_data {
+    # Adding sleep time so that metrics is pushed by podman exporter
+    sleep 60
+}
+
+function check_data_podman_exporter {
+    if curl -s --head  --request  GET "http://$HOST_IP:$PODMAN_EXPORTER_PORT/metrics" | grep "200 OK" > /dev/null; then
+        echo "#### Metrics data ####"
+        curl "http://$HOST_IP:$PODMAN_EXPORTER_PORT/metrics"
+    else
+        die $LINENO "Couldn't get data from podman_exporter"
+    fi
+}
+
+# Restore xtrace
+$_XTRACE_PODMAN_EXPORTER

devstack/plugin.sh

@@ -7,6 +7,7 @@ set -o xtrace
 echo_summary "devstack-plugin-prometheus's plugin.sh was called..."
 . $DEST/devstack-plugin-prometheus/devstack/lib/prometheus
 . $DEST/devstack-plugin-prometheus/devstack/lib/node_exporter
+. $DEST/devstack-plugin-prometheus/devstack/lib/podman_exporter
 
 # Show all of defined environment variables
 (set -o posix; set)
@@ -98,3 +99,48 @@ if is_service_enabled node_exporter; then
         cleanup_node_exporter
     fi
 fi
+
+## Podman Exporter
+if is_service_enabled podman_exporter; then
+    if [[ "$1" == "source" ]]; then
+        # Initial source of lib script
+        source $(dirname "$0")/lib/podman_exporter
+    fi
+
+    if [[ "$1" == "stack" && "$2" == "pre-install" ]]; then
+        # Set up system services
+        echo_summary "Configuring system services podman exporter"
+        pre_install_podman_exporter
+
+    elif [[ "$1" == "stack" && "$2" == "install" ]]; then
+        # Perform installation of service source
+        echo_summary "Installing podman exporter"
+        install_podman_exporter
+
+    elif [[ "$1" == "stack" && "$2" == "post-config" ]]; then
+        # Configure after the other layer 1 and 2 services have been configured
+        echo_summary "Configuring podman_exporter"
+        init_podman_exporter
+        echo_summary "Starting podman exporter service"
+        start_podman_exporter
+        echo_summary "Give time to podman_exporter to push metrics"
+        wait_for_podman_data
+        check_data_podman_exporter
+    fi
+
+    if [[ "$1" == "unstack" ]]; then
+        # Shut down podman exporter services
+        # no-op
+        echo_summary "Stoping podman_exporter service"
+        stop_podman_exporter
+
+    fi
+
+    if [[ "$1" == "clean" ]]; then
+        # Remove state and transient data
+        # Remember clean.sh first calls unstack.sh
+        # no-op
+        echo_summary "Cleaning podman exporter service"
+        cleanup_podman_exporter
+    fi
+fi

devstack/settings

@@ -1,5 +1,5 @@
 # DevStack settings
-define_plugin prometheus node_exporter
+define_plugin prometheus node_exporter podman_exporter
 enable_service prometheus
 enable_service node_exporter