Add .editorconfig file and ignore dist directory by git

.editorconfig

@@ -0,0 +1,15 @@
+root = true
+
+[*]
+indent_style = space
+indent_size = 4
+trim_trailing_whitespace = true
+insert_final_newline = true
+charset = utf-8
+end_of_line = lf
+
+[*.{yaml,yml}]
+indent_size = 2
+
+[Makefile]
+indent_style = tab

.gitignore

@@ -1,2 +1,3 @@
 *~
 /.env
+/dist

README.md

@@ -5,23 +5,34 @@ This script could be used as Nagios check plugin to verify Postgres Streaming re
 This script :
 
 -   check if Postgres is running (_CRITICAL_ raise if not)
-- check if Postgres is in recovery mode :
-  - if Postgres is in recovery mode :
-    - retrieve from Postgres the last _xlog_ file receive and the _xlog_ file replay
-    - check if Postgres recovery configuration file is NOT present (_CRITICAL_ raise if present)
-    - retrieve master connection information from Postgres recovery configuration file (_UNKNOWN_ raise on error). Default Postgres master TCP port will be used if port is not specify.
+-   check if Postgres is in recovery mode (using ̀`pg_is_in_recovery()`) :
+-   if the expected mode need to be auto-detected (default, see ̀`-e` parameter):
+    -   if Postgres is in recovery mode: `hot-standby`
+    -   if recovery file is present and contain `primary_conninfo`: `hot-standby`
+    -   otherwise: `master`
+-   if expected mode is `hot-standby`:
+    -   check if Postgres is in recovery mode (_CRITICAL_ raise if not)
+    -   retrieve from Postgres the last _xlog_ file received and the _xlog_ file replayed
+    -   retrieve master connection information from Postgres `primary_conninfo` configuration parameter (_UNKNOWN_ raise on error). Default Postgres master TCP port will be used if port is not specify.
+    -   retrieve master sync mode from `synchronous_commit` setting and assume synchronous commit is enabled if `synchronous_commit` is equal to `on` or `remote_apply`)
     -   retrieve the current state and sync state of the host from Postgres master server by making a connection on master server (_UNKNOWN_ raise on error).
-    - check if the current state of the host is "streaming" (_CRITICAL_ raise if not)
-    - check if the current sync state of the host is "sync" (or the state specified using `-e` parameter, _CRITICAL_ raise if not)
+    -   check if the current state of the host is `streaming` (_CRITICAL_ raise if not)
+    -   check if the current sync state of the host is the expected one (default: `sync`, see `-e` parameter, _CRITICAL_ raise if not)
     -   if the check of the current XLOG file of the master host is enabled :
         -   retrieve current _xlog_ file from Postgres master server by making a connection on master server (_UNKNOWN_ raise on error).
         -   check if the current master _xlog_ file is the last received _xlog_ file (_CRITICAL_ raise if not)
-    - check if the last received _xlog_ file is the last replay _xlog_ file : if not, check the current delay with the last replayed transaction against _replay_warn_delay_ and _replay_crit_delay_ thresholds and raise corresponding error if they are exceeded
-    - Return _OK_ state
-  - if Postgres is not in recovery mode :
-    - check if Postgres recovery configuration file is present (_CRITICAL_ raise if present)
-    - check if stand-by client(s) is connected (_WARNING_ raise if not)
-    - Return _OK_ state with list and count of stand-by client(s)
+    -   check if the last received _xlog_ file is the last replayed _xlog_ file : if not, check the current delay with the last replayed transaction against _replay_warn_delay_ and _replay_crit_delay_ thresholds and raise corresponding error if they are exceeded
+    -   if synchronous commit is enabled on master, check the last _xlog_ file sent by Postgres master is the last received by the slave. If not, retrieve difference (in bytes) and raise a _WARNING_.
+    -   if synchronous commit is disabled on master, check the last _xlog_ file sent by Postgres master is the last writed by the slave. If not, retrieve difference (in bytes) and raise a _WARNING_.
+    -   otherwise, return _OK_ state
+-   if expected mode is `master`:
+    -   check if Postgres is in recovery mode (_CRITICAL_ raise if it is)
+    -   retrieve current _xlog_ file (_UNKNOWN_ raise on error)
+    -   retrieve sync mode from `synchronous_commit` setting and assume synchronous commit is enabled if `synchronous_commit` is equal to `on` or `remote_apply`)
+    -   list stand-by client(s) from master and check for each to them:
+        -   if synchronous commit is enabled, check the last _xlog_ file sent by Postgres master is the current one on master (_WARNING_ raise if not)
+        -   if synchronous commit is disabled, check the last _xlog_ file sent by Postgres master is the laster writed one on master (_WARNING_ raise if not)
+    -   otherwise, return _OK_ state with list and count of stand-by client(s)
 
 **Note :** This script was originally write for PostgreSQL 9.1 and test on 9.1, 9.5, 9.6, 11, 13 and 15. Do not hesitate to tell me how this script work with other versions and share some fix. All contributions are welcome !
 
@@ -35,6 +46,18 @@ This script :
 
 ## Installation
 
+### From debian packages
+
+```
+echo "deb http://debian.zionetrix.net stable main" | sudo tee /etc/apt/sources.list.d/zionetrix.list
+sudo apt -o Acquire::AllowInsecureRepositories=true -o Acquire::AllowDowngradeToInsecureRepositories=true update
+sudo apt -o APT::Get::AllowUnauthenticated=true install --yes zionetrix-archive-keyring
+sudo apt update
+sudo apt install check-pg-streaming-replication
+```
+
+### From sources
+
 ```
 apt install sudo awk sed bc postgresql-client
 git clone https://gitea.zionetrix.net/bn8/check_pg_streaming_replication.git \
@@ -48,27 +71,34 @@ ln -s /usr/local/src/check_pg_streaming_replication/check_pg_streaming_replicati
 
 ```
 Usage: ./check_pg_streaming_replication [-d] [-h] [options]
-    -u pg_user              Specify local Postgres user (Default: try to auto-detect or use postgres)
+    -u pg_user              Specify local Postgres user (Default: try to auto-detect or
+                            use postgres)
     -b psql_bin             Specify psql binary path (Default: /usr/bin/psql)
     -B pg_lsclusters_bin    Specify pg_lsclusters binary path (Default: /usr/bin/pg_lsclusters)
-    -V pg_version           Specify Postgres version (Default: try to auto-detect or use 9.1)
-    -m pg_main              Specify Postgres main directory path (Default: try to auto-detect or use
-                            /var/lib/postgresql//main)
+    -V pg_version           Specify Postgres version (Default: try to auto-detect or
+                            use 9.1)
+    -m pg_main              Specify Postgres main directory path (Default: try to auto-detect or
+                            use /var/lib/postgresql//main)
     -r recovery_conf        Specify Postgres recovery configuration file path
-                (           Default: [PG_MAIN]/recovery.conf on PG <= 11, [PG_MAIN]/postgresql.auto.conf on PG >= 12)
-    -U pg_master_user       Specify Postgres user to use on master (Default: user from recovery.conf file)
-    -p pg_port              Specify default Postgres master TCP port (Default: same as local PostgreSQL
-                            port if detected or use 5432)
-    -D dbname               Specify DB name on Postgres master/slave to connect on (Default: PG_USER, must
-                            match with .pgpass one is used)
-    -C 1/0                  Enable or disable check if the current LSN of the master host is the same
-                            of the last received LSN (Default: 1)
-    -w replay_warn_delay    Specify the replay warning delay in second (Default: 3)
-    -c replay_crit_delay    Specify the replay critical delay in second (Default: 5)
-    -e expected_sync_state  The expected replication state ('sync' or 'async', default: sync)
-    -E expected_mode        The expected mode ('master', 'hot-standby' or 'auto', default: 'auto')
+                            (Default: [PG_MAIN]/recovery.conf on PG <= 11,
+                            [PG_MAIN]/postgresql.auto.conf on PG >= 12)
+    -U pg_master_user       Specify Postgres user to use on master (Default: user from recovery.conf
+                            file)
+    -p pg_port              Specify default Postgres master TCP port (Default: same as local
+                            PostgreSQL port if detected or use 5432)
+    -D dbname               Specify DB name on Postgres master/slave to connect on (Default:
+                            PG_USER, must match with .pgpass one is used)
+    -w replay_warn_delay    Specify the replay warning delay in second
+                            (Default: 3)
+    -c replay_crit_delay    Specify the replay critical delay in second
+                            (Default: 5)
+    -e expected_sync_state  The expected replication state ('sync' or 'async',
+                            default: sync)
+    -E expected_mode        The expected mode ('master', 'hot-standby' or 'auto',
+                            default: 'auto')
     -d                      Debug mode
     -h                      Show this message
+
 ```
 
 ## Copyright

build.sh

@@ -1,16 +1,21 @@
 #!/bin/bash
+# vim: tabstop=4 shiftwidth=4 softtabstop=4 expandtab
 
-QUIET_ARG=""
-[[ "$1" == "--quiet" ]] && QUIET_ARG="--quiet"
+set -e
+
+QUIET_MODE=0
+[[ "$1" == "--quiet" ]] && QUIET_MODE=1
 
 # Enter source directory
 cd "$( dirname "$0" )" || exit
 
-CHECK_FILE="$( find "." -name 'check_*' ! -name '*~' -type f -executable | head -n 1 )"
-PACKAGE_NAME="$( basename "$CHECK_FILE" | tr '_' '-' )"
+if [[ -d dist ]]; then
+    echo "Clean previous build..."
+    rm -fr dist
+fi
 
-echo "Clean previous build..."
-rm -fr dist
+CHECK_FILE="$( find "." -maxdepth 1 -name 'check_*' ! -name '*~' -type f -executable | head -n 1 )"
+PACKAGE_NAME="$( basename "$CHECK_FILE" | tr '_' '-' )"
 
 echo "Detect version using git describe..."
 VERSION="$( git describe --tags|sed 's/^[^0-9]*//' )"
@@ -18,13 +23,46 @@ VERSION="$( git describe --tags|sed 's/^[^0-9]*//' )"
 echo "Create building environemt..."
 BDIR="dist/$PACKAGE_NAME-$VERSION"
 mkdir -p "$BDIR"
-RSYNC_ARG=""
-[[ -z "$QUIET_ARG" ]] && RSYNC_ARG="-v"
-rsync -a "$RSYNC_ARG" debian/ "$BDIR/debian/"
+RSYNC_ARGS=( )
+[[ $QUIET_MODE -eq 0 ]] && RSYNC_ARGS+=( -v )
+rsync -a "${RSYNC_ARGS[@]}" debian/ "$BDIR/debian/"
 cp "$CHECK_FILE" "$BDIR/"
 
-echo "Set VERSION=$VERSION in gitdch using sed..."
-sed -i "s/^VERSION *=.*$/VERSION = '$VERSION'/" "$BDIR/$( basename "$CHECK_FILE" )"
+if [[ -e "README.md" ]]; then
+    echo "Build manpage from README.md file..."
+    MAN_TITLE=$( basename "$CHECK_FILE" )
+    MAN_MD_FILE="$BDIR/$( basename "$CHECK_FILE" ).1.md"
+    MAN_FILE="$BDIR/$( basename "$CHECK_FILE" ).1"
+    echo "# ${MAN_TITLE^^} 1" \
+        "$( git log --follow --format=%ad --date iso README.md | head -n 1 | awk '{print $1}')" \
+        "$PACKAGE_NAME" \
+        '"User Manuals"' > "$MAN_MD_FILE"
+    sed 1d README.md >> "$MAN_MD_FILE"
+    if ! which go-md2man > /dev/null; then
+        ARG_ARGS=()
+        [[ $QUIET_MODE -eq 0 ]] && ARG_ARGS+=( -qq )
+        apt update "${ARG_ARGS[@]}"
+        apt install -y "${ARG_ARGS[@]}" go-md2man
+    fi
+    go-md2man -in "$MAN_MD_FILE" -out "$MAN_FILE"
+    basename "$MAN_FILE" >> "$BDIR/debian/manpages"
+    grep -Eq '^Build-Depends: .*go-md2man' "$BDIR/debian/control" || \
+        sed -i 's/^Build-Depends: \(.*\)$/Build-Depends: \1, go-md2man/' "$BDIR/debian/control"
+fi
+
+if grep -Eq '^VERSION *=' "$BDIR/$( basename "$CHECK_FILE" )"; then
+    echo "Set VERSION=$VERSION in $( basename "$CHECK_FILE" ) using sed..."
+    sed -i "s/^VERSION *=.*$/VERSION = '$VERSION'/" "$BDIR/$( basename "$CHECK_FILE" )"
+elif grep -Eq '^# Version:' "$BDIR/$( basename "$CHECK_FILE" )"; then
+    echo "Set Version = $VERSION in $( basename "$CHECK_FILE" ) using sed..."
+    sed -i "s/^#\(\s*Version:\s*\).*$/#\1$VERSION/" "$BDIR/$( basename "$CHECK_FILE" )"
+fi
+
+if grep -Eq '^# Date:' "$BDIR/$( basename "$CHECK_FILE" )"; then
+    DATE="$( git log --follow --format=%ad --date iso "$CHECK_FILE" | head -n 1 )"
+    echo "Set Date = $DATE in $( basename "$CHECK_FILE" ) using sed..."
+    sed -i "s/^#\(\s*Date:\s*\).*$/#\1$DATE/" "$BDIR/$( basename "$CHECK_FILE" )"
+fi
 
 if [[ -z "$DEBIAN_CODENAME" ]]; then
     echo "Retrieve debian codename using lsb_release..."
@@ -35,7 +73,7 @@ fi
 
 echo "Generate debian changelog using gitdch..."
 GITDCH_ARGS=('--verbose')
-[[ -n "$QUIET_ARG" ]] && GITDCH_ARGS=('--warning')
+[[ $QUIET_MODE -eq 1 ]] && GITDCH_ARGS=('--warning')
 if [[ -n "$MAINTAINER_NAME" ]]; then
     echo "Use maintainer name from environment ($MAINTAINER_NAME)"
     GITDCH_ARGS+=("--maintainer-name" "${MAINTAINER_NAME}")
@@ -60,4 +98,5 @@ fi
 
 echo "Build debian package..."
 cd "$BDIR" || exit
+[[ $QUIET_MODE -eq 0 ]] && export DH_VERBOSE=1
 dpkg-buildpackage

check_pg_streaming_replication

@@ -20,7 +20,8 @@
 #                      ~/.pgpass).
 #
 # Author: Benjamin Renard <brenard@easter-eggs.com>
-# Date: Mon, 03 Jun 2024 15:31:29 +0200
+# Version: dev
+# Date: dev
 # Source: https://gitea.zionetrix.net/bn8/check_pg_streaming_replication
 # SPDX-License-Identifier: GPL-3.0-or-later
 #
@@ -39,7 +40,6 @@ RECOVERY_CONF=""
 PG_DEFAULT_PORT=""
 PG_DEFAULT_APP_NAME=$( hostname )
 PG_DB=""
-CHECK_CUR_MASTER_LSN=1
 REPLAY_WARNING_DELAY=3
 REPLAY_CRITICAL_DELAY=5
 EXPECTED_SYNC_STATE=sync
@@ -48,36 +48,42 @@ EXPECTED_MODE=auto
 DEBUG=0
 
 function usage () {
-    ERROR="$1"
+    ERROR="$*"
     [[ -n "$ERROR" ]] && echo -e "$ERROR\n"
     cat << EOF
 Usage: $0 [-d] [-h] [options]
-    -u pg_user              Specify local Postgres user (Default: try to auto-detect or use $DEFAULT_PG_USER)
+    -u pg_user              Specify local Postgres user (Default: try to auto-detect or
+                            use $DEFAULT_PG_USER)
     -b psql_bin             Specify psql binary path (Default: $PSQL_BIN)
     -B pg_lsclusters_bin    Specify pg_lsclusters binary path (Default: $PG_LSCLUSTER_BIN)
-    -V pg_version           Specify Postgres version (Default: try to auto-detect or use $DEFAULT_PG_VERSION)
-    -m pg_main              Specify Postgres main directory path (Default: try to auto-detect or use
-                            $DEFAULT_PG_MAIN)
+    -V pg_version           Specify Postgres version (Default: try to auto-detect or
+                            use $DEFAULT_PG_VERSION)
+    -m pg_main              Specify Postgres main directory path (Default: try to auto-detect or
+                            use $DEFAULT_PG_MAIN)
     -r recovery_conf        Specify Postgres recovery configuration file path
-                            (Default: [PG_MAIN]/recovery.conf on PG <= 11, [PG_MAIN]/postgresql.auto.conf on PG >= 12)
-    -U pg_master_user       Specify Postgres user to use on master (Default: user from recovery.conf file)
-    -p pg_port              Specify default Postgres master TCP port (Default: same as local PostgreSQL
-                            port if detected or use $DEFAULT_PG_PORT)
-    -D dbname               Specify DB name on Postgres master/slave to connect on (Default: PG_USER, must
-                            match with .pgpass one is used)
-    -C 1/0                  Enable or disable check if the current LSN of the master host is the same
-                            of the last received LSN (Default: $CHECK_CUR_MASTER_LSN)
-    -w replay_warn_delay    Specify the replay warning delay in second (Default: $REPLAY_WARNING_DELAY)
-    -c replay_crit_delay    Specify the replay critical delay in second (Default: $REPLAY_CRITICAL_DELAY)
-    -e expected_sync_state  The expected replication state ('sync' or 'async', default: $EXPECTED_SYNC_STATE)
-    -E expected_mode        The expected mode ('master', 'hot-standby' or 'auto', default: '$EXPECTED_MODE')
+                            (Default: [PG_MAIN]/recovery.conf on PG <= 11,
+                            [PG_MAIN]/postgresql.auto.conf on PG >= 12)
+    -U pg_master_user       Specify Postgres user to use on master (Default: user from recovery.conf
+                            file)
+    -p pg_port              Specify default Postgres master TCP port (Default: same as local
+                            PostgreSQL port if detected or use $DEFAULT_PG_PORT)
+    -D dbname               Specify DB name on Postgres master/slave to connect on (Default:
+                            PG_USER, must match with .pgpass one is used)
+    -w replay_warn_delay    Specify the replay warning delay in second
+                            (Default: $REPLAY_WARNING_DELAY)
+    -c replay_crit_delay    Specify the replay critical delay in second
+                            (Default: $REPLAY_CRITICAL_DELAY)
+    -e expected_sync_state  The expected replication state ('sync' or 'async',
+                            default: $EXPECTED_SYNC_STATE)
+    -E expected_mode        The expected mode ('master', 'hot-standby' or 'auto',
+                            default: '$EXPECTED_MODE')
     -d                      Debug mode
     -h                      Show this message
 EOF
     [[ -n "$ERROR" ]] && exit 1 || exit 0
 }
 
-while getopts "hu:b:B:V:m:r:U:p:D:C:w:c:e:E:d" OPTION; do
+while getopts "hu:b:B:V:m:r:U:p:D:w:c:e:E:d" OPTION; do
     case $OPTION in
         u)
             PG_USER=$OPTARG
@@ -106,9 +112,6 @@ while getopts "hu:b:B:V:m:r:U:p:D:C:w:c:e:E:d" OPTION; do
         D)
             PG_DB=$OPTARG
         ;;
-        C)
-            CHECK_CUR_MASTER_LSN=$OPTARG
-        ;;
         w)
             REPLAY_WARNING_DELAY=$OPTARG
         ;;
@@ -117,12 +120,15 @@ while getopts "hu:b:B:V:m:r:U:p:D:C:w:c:e:E:d" OPTION; do
         ;;
         e)
             [[ "$OPTARG" != "sync" ]] && [[ "$OPTARG" != "async" ]] && \
-                usage "Invalid expected replication state '$OPTARG'. Possible values: sync or async."
+                usage "Invalid expected replication state '$OPTARG'." \
+                  "Possible values: sync or async."
             EXPECTED_SYNC_STATE=$OPTARG
         ;;
         E)
-            [[ "$OPTARG" != "master" ]] && [[ "$OPTARG" != "hot-standby" ]] && [[ "$OPTARG" != "auto" ]] && \
-                usage "Invalid expected mode '$OPTARG'. Possible values: master, hot-standby or auto."
+            [[ "$OPTARG" != "master" ]] && [[ "$OPTARG" != "hot-standby" ]] && \
+                [[ "$OPTARG" != "auto" ]] && \
+                    usage "Invalid expected mode '$OPTARG'. Possible values: master, hot-standby" \
+                        "or auto."
             EXPECTED_MODE=$OPTARG
         ;;
         d)
@@ -139,7 +145,7 @@ done
 
 function debug() {
     if [[ $DEBUG -eq 1 ]]; then
-        >&2 echo -e "[DEBUG] $1"
+        >&2 echo -e "[DEBUG] $*"
     fi
 }
 
@@ -153,7 +159,6 @@ PG_MAIN = $PG_MAIN
 RECOVERY_CONF = $RECOVERY_CONF
 PG_DEFAULT_PORT = $PG_DEFAULT_PORT
 PG_DEFAULT_APP_NAME = $PG_DEFAULT_APP_NAME
-CHECK_CUR_MASTER_LSN = $CHECK_CUR_MASTER_LSN
 REPLAY_WARNING_DELAY = $REPLAY_WARNING_DELAY
 REPLAY_CRITICAL_DELAY = $REPLAY_CRITICAL_DELAY
 EXPECTED_SYNC_STATE = $EXPECTED_SYNC_STATE
@@ -162,15 +167,19 @@ EXPECTED_MODE = $EXPECTED_MODE
 
 # Auto-detect PostgreSQL information using pg_lsclusters
 if [[ -x "$PG_LSCLUSTER_BIN" ]]; then
-    PG_CLUSTER=$( $PG_LSCLUSTER_BIN -h 2>/dev/null|head -n1 )
+    PG_CLUSTER=$( $PG_LSCLUSTER_BIN -h 2>/dev/null | head -n1 )
     if [[ -n "$PG_CLUSTER" ]]; then
         debug "pg_lsclusters output:\n\t$PG_CLUSTER"
         # Output example:
-        # 9.6 main    5432 online,recovery postgres /var/lib/postgresql/9.6/main /var/log/postgresql/postgresql-9.6-main.log
-        [[ -z "$PG_VERSION" ]] && PG_VERSION=$( echo "$PG_CLUSTER"|awk -F ' +' '{print $1}' )
-        [[ -z "$PG_DEFAULT_PORT" ]] && PG_DEFAULT_PORT=$( echo "$PG_CLUSTER"|awk -F ' +' '{print $3}' )
-        [[ -z "$PG_USER" ]] && PG_USER=$( echo "$PG_CLUSTER"|awk -F ' +' '{print $5}' )
-        [[ -z "$PG_MAIN" ]] && PG_MAIN=$( echo "$PG_CLUSTER"|awk -F ' +' '{print $6}' )
+        # 9.6 main    5432 online,recovery postgres /var/lib/postgresql/9.6/main \
+        #   /var/log/postgresql/postgresql-9.6-main.log
+        # 13  main    5432 online,recovery,pacemaker postgres /var/lib/postgresql/13/main \
+        #   /var/log/postgresql/postgresql-13-main.log
+        [[ -z "$PG_VERSION" ]] && PG_VERSION=$( awk -F ' +' '{print $1}' <<< "$PG_CLUSTER" )
+        [[ -z "$PG_DEFAULT_PORT" ]] && \
+            PG_DEFAULT_PORT=$( awk -F ' +' '{print $3}' <<< "$PG_CLUSTER" )
+        [[ -z "$PG_USER" ]] && PG_USER=$( awk -F ' +' '{print $5}' <<< "$PG_CLUSTER" )
+        [[ -z "$PG_MAIN" ]] && PG_MAIN=$( awk -F ' +' '{print $6}' <<< "$PG_CLUSTER" )
     fi
 else
     debug "pg_lsclusters not found ($PG_LSCLUSTER_BIN): parameters auto-detection disabled"
@@ -194,7 +203,11 @@ id "$PG_USER" > /dev/null 2>&1 || { echo "UNKNOWN: Invalid Postgres user ($PG_US
 
 # Check RECOVERY_CONF
 if [[ -z "$RECOVERY_CONF" ]]; then
-    [[ $PG_VERSION -le 11 ]] && RECOVERY_CONF_FILENAME="recovery.conf" || RECOVERY_CONF_FILENAME="postgresql.auto.conf"
+    if [[ $PG_VERSION -le 11 ]]; then
+        RECOVERY_CONF_FILENAME="recovery.conf"
+    else
+        RECOVERY_CONF_FILENAME="postgresql.auto.conf"
+    fi
     RECOVERY_CONF="$PG_MAIN/$RECOVERY_CONF_FILENAME"
 else
     RECOVERY_CONF_FILENAME=$( basename "$RECOVERY_CONF" )
@@ -208,15 +221,17 @@ fi
 [[ -z "$PG_DB" ]] && PG_DB="$PG_USER"
 
 function psql_get () {
-    sql="$1"
-    debug "Exec 'echo \"$sql\"|sudo -u $PG_USER $PSQL_BIN -d \"$PG_DB\" -w -t -P format=unaligned"
+    local sql="$*"
+    debug "Exec 'sudo -u $PG_USER $PSQL_BIN -d \"$PG_DB\" -w -t -P format=unaligned <<< \"$sql\""
     sudo -u "$PG_USER" "$PSQL_BIN" -d "$PG_DB" -w -t -P format=unaligned <<< "$sql"
 }
 
 function psql_master_get () {
-    sql="$1"
-    debug "Exec 'echo \"$sql\"|sudo -u $PG_USER $PSQL_BIN -U $M_USER -h $M_HOST -w -p $M_PORT -d $PG_DB -t -P format=unaligned"
-    sudo -u "$PG_USER" "$PSQL_BIN" -U "$M_USER" -h "$M_HOST" -w -p "$M_PORT" -d "$PG_DB" -t -P format=unaligned <<< "$sql"
+    local sql="$*"
+    debug "Exec 'sudo -u $PG_USER $PSQL_BIN -U $M_USER -h $M_HOST -w -p $M_PORT -d $PG_DB -t" \
+        "-P format=unaligned <<< \"$sql\""
+    sudo -u "$PG_USER" "$PSQL_BIN" \
+        -U "$M_USER" -h "$M_HOST" -w -p "$M_PORT" -d "$PG_DB" -t -P format=unaligned <<< "$sql"
 }
 
 debug "Running options:
@@ -229,7 +244,6 @@ PG_MAIN = $PG_MAIN
 RECOVERY_CONF = $RECOVERY_CONF
 PG_DEFAULT_PORT = $PG_DEFAULT_PORT
 PG_DEFAULT_APP_NAME = $PG_DEFAULT_APP_NAME
-CHECK_CUR_MASTER_LSN = $CHECK_CUR_MASTER_LSN
 REPLAY_WARNING_DELAY = $REPLAY_WARNING_DELAY
 REPLAY_CRITICAL_DELAY = $REPLAY_CRITICAL_DELAY
 "
@@ -273,7 +287,8 @@ if [[ "$EXPECTED_MODE" == "auto" ]]; then
     if [[ $RECOVERY_MODE -eq 1 ]]; then
         debug "Postgres is in recovery mode. Hot-standby mode."
         EXPECTED_MODE="hot-standby"
-    elif [[ -f $RECOVERY_CONF ]] && [[ $( grep -cE '^\s*primary_conninfo' "$RECOVERY_CONF" ) -gt 0 ]]; then
+    elif [[ -f $RECOVERY_CONF ]] && \
+        [[ $( grep -cE '^\s*primary_conninfo' "$RECOVERY_CONF" ) -gt 0 ]]; then
         debug "File $RECOVERY_CONF_FILENAME found and contain primary_conninfo. Hot-standby mode."
         EXPECTED_MODE="hot-standby"
     else
@@ -301,19 +316,24 @@ if [[ "$EXPECTED_MODE" == "hot-standby" ]]; then
     # Get master connection information from primary_conninfo configuration parameter
     MASTER_CONN_INFOS=$( psql_get "SHOW primary_conninfo" )
     if [[ -z "$MASTER_CONN_INFOS" ]]; then
-        echo "UNKNOWN: Can't retrieve master connection information from primary_conninfo configuration parameter"
+        echo "UNKNOWN: Can't retrieve master connection information from primary_conninfo" \
+            "configuration parameter"
         exit 3
     fi
     debug "Master connection information: $MASTER_CONN_INFOS"
 
-    M_HOST=$( grep 'host=' <<< "$MASTER_CONN_INFOS" | sed 's/^.*host= *\([0-9a-zA-Z.-]\+\) *.*$/\1/' )
+    M_HOST=$(
+        grep 'host=' <<< "$MASTER_CONN_INFOS" | sed 's/^.*host= *\([0-9a-zA-Z.-]\+\) *.*$/\1/'
+    )
     if [[ -z "$M_HOST" ]]; then
         echo "UNKNOWN: Can't retrieve master host from primary_conninfo configuration parameter"
         exit 3
     fi
     debug "Master host: $M_HOST"
 
-    M_PORT=$( grep 'port=' <<< "$MASTER_CONN_INFOS" | sed 's/^.*port= *\([0-9a-zA-Z.-]\+\) *.*$/\1/' )
+    M_PORT=$(
+        grep 'port=' <<< "$MASTER_CONN_INFOS" | sed 's/^.*port= *\([0-9a-zA-Z.-]\+\) *.*$/\1/'
+    )
     if [[ -z "$M_PORT" ]]; then
         debug "Master port not specified, use default: $PG_DEFAULT_PORT"
         M_PORT=$PG_DEFAULT_PORT
@@ -325,7 +345,9 @@ if [[ "$EXPECTED_MODE" == "hot-standby" ]]; then
         debug "Master user provided by command-line, use it: $PG_MASTER_USER"
         M_USER="$PG_MASTER_USER"
     else
-        M_USER=$( grep 'user=' <<< "$MASTER_CONN_INFOS" | sed 's/^.*user= *\([0-9a-zA-Z.-]\+\) *.*$/\1/' )
+        M_USER=$(
+            grep 'user=' <<< "$MASTER_CONN_INFOS" | sed 's/^.*user= *\([0-9a-zA-Z.-]\+\) *.*$/\1/'
+        )
         if [[ -z "$M_USER" ]]; then
             debug "Master user not specified, use default: $PG_USER"
             M_USER=$PG_USER
@@ -334,7 +356,10 @@ if [[ "$EXPECTED_MODE" == "hot-standby" ]]; then
         fi
     fi
 
-    M_APP_NAME=$( grep 'application_name=' <<< "$MASTER_CONN_INFOS" | sed "s/^.*application_name=[ \'\"]*\([^ \'\"]\+\)[ \'\"]*.*$/\1/" )
+    M_APP_NAME=$(
+        grep 'application_name=' <<< "$MASTER_CONN_INFOS" |
+            sed "s/^.*application_name=[ \'\"]*\([^ \'\"]\+\)[ \'\"]*.*$/\1/"
+    )
     if [[ -z "$M_APP_NAME" ]]; then
         if [[ $PG_VERSION -ge 12 ]]; then
             debug "Master application name not specified, use cluster_name if defined"
@@ -354,25 +379,45 @@ if [[ "$EXPECTED_MODE" == "hot-standby" ]]; then
         debug "Master application name: $M_APP_NAME"
     fi
 
+    # Check if master is configured for synchronous commit
+    SYNC_MODE="$(
+        psql_master_get "SELECT setting from pg_settings WHERE name = 'synchronous_commit';"
+    )"
+    debug "Master synchronous_commit=$SYNC_MODE"
+    if [[ "$SYNC_MODE" == "on" ]] || [[ "$SYNC_MODE" == "remote_apply" ]]; then
+        debug "Master is configured for synchronous commit"
+        SYNCHRONOUS_COMMIT=1
+    else
+        debug "Master is not configured for synchronous commit"
+        SYNCHRONOUS_COMMIT=0
+    fi
+
     # Get current replication state information from master
-    M_CUR_REPL_STATE_INFO="$( psql_master_get "SELECT state, sync_state, $sent_lsn AS sent_lsn, $write_lsn AS write_lsn FROM pg_stat_replication WHERE application_name='$M_APP_NAME';" )"
+    M_CUR_REPL_STATE_INFO="$(
+        psql_master_get \
+            "SELECT state, sync_state, $sent_lsn AS sent_lsn, $write_lsn AS write_lsn" \
+            "FROM pg_stat_replication WHERE application_name='$M_APP_NAME';"
+    )"
     if [[ -z "$M_CUR_REPL_STATE_INFO" ]]; then
         echo "UNKNOWN: Can't retrieve current replication state information from master server"
         exit 3
     fi
-    debug "Master current replication state:\n\tstate|sync_state|sent_lsn|write_lsn\n\t$M_CUR_REPL_STATE_INFO"
+    debug "Master current replication state:\n" \
+        "\tstate|sync_state|sent_lsn|write_lsn\n\t$M_CUR_REPL_STATE_INFO"
 
     M_CUR_STATE=$( cut -d'|' -f1 <<< "$M_CUR_REPL_STATE_INFO" )
     debug "Master current state: $M_CUR_STATE"
     if [[ "$M_CUR_STATE" != "streaming" ]]; then
-        echo "CRITICAL: this host is not in streaming state according to master host (current state = '$M_CUR_STATE')"
+        echo "CRITICAL: this host is not in streaming state according to master host" \
+            "(current state = '$M_CUR_STATE')"
         exit 2
     fi
 
     M_CUR_SYNC_STATE=$( cut -d'|' -f2 <<< "$M_CUR_REPL_STATE_INFO" )
     debug "Master current sync state: $M_CUR_SYNC_STATE"
     if [[ "$M_CUR_SYNC_STATE" != "$EXPECTED_SYNC_STATE" ]]; then
-        echo "CRITICAL: unexpected replication state '$M_CUR_SYNC_STATE' (expected state = '$EXPECTED_SYNC_STATE')"
+        echo "CRITICAL: unexpected replication state '$M_CUR_SYNC_STATE'" \
+            "(expected state = '$EXPECTED_SYNC_STATE')"
         exit 2
     fi
 
@@ -380,35 +425,24 @@ if [[ "$EXPECTED_MODE" == "hot-standby" ]]; then
     M_CUR_WRITED_LSN=$( cut -d'|' -f4 <<< "$M_CUR_REPL_STATE_INFO" )
     debug "Master current last sent/writed LSN: '$M_CUR_SENT_LSN' / '$M_CUR_WRITED_LSN'"
 
-    # Check current master LSN vs last received LSN
-    if [[ "$CHECK_CUR_MASTER_LSN" == "1" ]]; then
-        # Get current LSN from master
-        M_CUR_LSN="$( psql_master_get "SELECT $pg_current_wal_lsn" )"
-        if [[ -z "$M_CUR_LSN" ]]; then
-            echo "UNKNOWN: Can't retrieve current LSN from master server"
-            exit 3
-        fi
-        debug "Master current LSN: $M_CUR_LSN"
-
-        # Master current LSN is the last received LSN ?
-        if [[ "$M_CUR_LSN" != "$LAST_RECEIVED_LSN" ]]; then
-            echo "CRITICAL: Master current LSN is not the last received LSN"
-            exit 2
-        fi
-        debug "Master current LSN is the last received LSN"
-    fi
-
     # The last received LSN is the last replayed ?
     if [[ "$LAST_RECEIVED_LSN" != "$LAST_REPLAYED_LSN" ]]; then
-        debug "/!\ The last received LSN is NOT the last replayed LSN ('$M_CUR_LSN' / '$LAST_REPLAYED_LSN')"
-        REPLAY_DELAY="$( psql_get 'SELECT EXTRACT(EPOCH FROM now() - pg_last_xact_replay_timestamp());' )"
+        debug "/!\ The last received LSN is NOT the last replayed LSN" \
+            "('$M_CUR_LSN' / '$LAST_REPLAYED_LSN')"
+        REPLAY_DELAY="$(
+            psql_get 'SELECT EXTRACT(EPOCH FROM now() - pg_last_xact_replay_timestamp());'
+        )"
         debug "Replay delay is $REPLAY_DELAY second(s)"
         if [[ $( bc -l <<< "$REPLAY_DELAY >= $REPLAY_CRITICAL_DELAY" ) -gt 0 ]]; then
-            echo "CRITICAL: last received LSN is not the last replayed ('$LAST_RECEIVED_LSN' / '$LAST_REPLAYED_LSN') and replay delay is $REPLAY_DELAY second(s)"
+            echo "CRITICAL: last received LSN is not the last replayed" \
+                "('$LAST_RECEIVED_LSN' / '$LAST_REPLAYED_LSN') and" \
+                "replay delay is $REPLAY_DELAY second(s)"
             exit 2
         fi
         if [[ $( bc -l <<< "$REPLAY_DELAY >= $REPLAY_WARNING_DELAY" ) -gt 0 ]]; then
-            echo "WARNING: last received LSN is not the last replay file ('$LAST_RECEIVED_LSN' / '$LAST_REPLAYED_LSN') and replay delay is $REPLAY_DELAY second(s)"
+            echo "WARNING: last received LSN is not the last replay file" \
+                "('$LAST_RECEIVED_LSN' / '$LAST_REPLAYED_LSN') and" \
+                "replay delay is $REPLAY_DELAY second(s)"
             exit 1
         fi
         debug "Replay delay is not worrying"
@@ -416,10 +450,27 @@ if [[ "$EXPECTED_MODE" == "hot-standby" ]]; then
     debug "Last received LSN is the last replayed file"
 
     # The master last sent LSN is the last received (and synced) ?
-    if [[ "$M_CUR_SENT_LSN" != "$LAST_RECEIVED_LSN" ]]; then
-        echo "WARNING: master last sent LSN is not already received (and synced to disk) by slave. May be we have some network delay or load on slave"
+    if [[ $SYNCHRONOUS_COMMIT -eq 1 ]] && [[ "$M_CUR_SENT_LSN" != "$LAST_RECEIVED_LSN" ]]; then
+        LSN_DIFF=$(
+            psql_master_get "SELECT $pg_wal_lsn_diff('$M_CUR_SENT_LSN', '$LAST_RECEIVED_LSN');"
+        )
+        debug "LSN diff ('$M_CUR_SENT_LSN' vs '$LAST_RECEIVED_LSN'): $LSN_DIFF bytes"
+        echo "WARNING: master last sent LSN is not already received (and synced to disk) by slave" \
+            "(diff: $LSN_DIFF bytes). May be we have some network delay or load on slave"
         echo "Master last sent LSN: $M_CUR_SENT_LSN"
         echo "Slave last received (and synced to disk) LSN: $LAST_RECEIVED_LSN"
+        echo "Diff: $LSN_DIFF bytes"
+        exit 1
+    elif [[ $SYNCHRONOUS_COMMIT -eq 0 ]] && [ "$M_CUR_SENT_LSN" != "$M_CUR_WRITED_LSN" ];then
+        LSN_DIFF=$(
+            psql_master_get "SELECT pg_wal_lsn_diff('$M_CUR_SENT_LSN', '$M_CUR_WRITED_LSN');"
+        )
+        debug "LSN diff ('$M_CUR_SENT_LSN' vs '$M_CUR_WRITED_LSN'): $LSN_DIFF bytes"
+        echo "WARNING: master last sent LSN is not already received by slave " \
+            "(diff: $LSN_DIFF bytes). May be we have some network delay or load on slave"
+        echo "Master last sent LSN: $M_CUR_SENT_LSN"
+        echo "Slave last received LSN: $M_CUR_WRITED_LSN"
+        echo "Diff: $LSN_DIFF bytes"
         exit 1
     fi
 
@@ -444,28 +495,44 @@ elif [[ "$EXPECTED_MODE" == "master" ]]; then
     fi
     debug "Current LSN: $CURRENT_LSN"
 
+    # Check if master is configured for synchronous commit
+    SYNC_MODE="$( psql_get "SELECT setting from pg_settings WHERE name = 'synchronous_commit';" )"
+    debug "synchronous_commit=$SYNC_MODE"
+    if [[ "$SYNC_MODE" == "on" ]] || [[ "$SYNC_MODE" == "remote_apply" ]]; then
+        debug "Master is configured for synchronous commit"
+        SYNCHRONOUS_COMMIT=1
+    else
+        debug "Master is not configured for synchronous commit"
+        SYNCHRONOUS_COMMIT=0
+    fi
+
     # Check standby client
-    STANDBY_CLIENTS=$( psql_get "SELECT application_name, client_addr, sent_lsn, write_lsn, state, sync_state, current_lag
+    STANDBY_CLIENTS=$(
+        psql_get \
+            "SELECT
+                application_name, client_addr, sent_lsn, write_lsn, state, sync_state, current_lag
             FROM (
-      SELECT application_name, client_addr, sent_lsn, write_lsn, state, sync_state, current_lag
+                SELECT
+                    application_name, client_addr, sent_lsn, write_lsn, state, sync_state,
+                    current_lag
                 FROM (
-        SELECT application_name, client_addr, $sent_lsn AS sent_lsn, $write_lsn AS write_lsn, state, sync_state,
+                    SELECT
+                        application_name, client_addr, $sent_lsn AS sent_lsn,
+                        $write_lsn AS write_lsn, state, sync_state,
                         $pg_wal_lsn_diff($pg_current_wal_lsn, $write_lsn) AS current_lag
                     FROM pg_stat_replication
                 ) AS s2
-    ) AS s1" )
+            ) AS s1"
+    )
     if [[ -z "$STANDBY_CLIENTS" ]]; then
         echo "WARNING: no stand-by client connected"
         exit 1
     fi
     debug "Stand-by client(s):\n\t${STANDBY_CLIENTS//$'\n'/\\n\\t}"
 
-    STANDBY_CLIENTS_TXT=""
-    STANDBY_CLIENTS_COUNT=0
+    STANDBY_CLIENTS_ROWS=()
     CURRENT_LSN_IS_LAST_SENT=1
     for line in $STANDBY_CLIENTS; do
-        (( STANDBY_CLIENTS_COUNT+=1 ))
-
         NAME=$( cut -d '|' -f 1 <<< "$line" )
         IP=$( cut -d '|' -f 2 <<< "$line" )
         SENT_LSN=$( cut -d '|' -f 3 <<< "$line" )
@@ -473,20 +540,28 @@ elif [[ "$EXPECTED_MODE" == "master" ]]; then
         STATE=$( cut -d '|' -f 5 <<< "$line" )
         SYNC_STATE=$( cut -d '|' -f 6 <<< "$line" )
         LAG=$( cut -d '|' -f 7 <<< "$line" )
-        STANDBY_CLIENTS_TXT="$STANDBY_CLIENTS_TXT\n$NAME ($IP): $STATE/$SYNC_STATE (LSN: sent='$SENT_LSN' / writed='$WRITED_LSN', Lag: ${LAG}b)"
-        [[ "$SENT_LSN" != "$CURRENT_LSN" ]] && CURRENT_LSN_IS_LAST_SENT=0
+        STANDBY_CLIENTS_ROW="$NAME ($IP): $STATE/$SYNC_STATE"
+        STANDBY_CLIENTS_ROW+=" (LSN: sent='$SENT_LSN' / writed='$WRITED_LSN', Lag: ${LAG}b"
+        STANDBY_CLIENTS_ROWS+=( "$STANDBY_CLIENTS_ROW" )
+        if [[ $SYNCHRONOUS_COMMIT -eq 1 ]] && [[ "$SENT_LSN" != "$CURRENT_LSN" ]]; then
+            CURRENT_LSN_IS_LAST_SENT=0
+        elif [[ $SYNCHRONOUS_COMMIT -eq 0 ]] && [[ "$SENT_LSN" != "$WRITED_LSN" ]]; then
+            CURRENT_LSN_IS_LAST_SENT=0
+        fi
     done
 
     if [[ $CURRENT_LSN_IS_LAST_SENT -eq 1 ]]; then
-        echo "OK: $STANDBY_CLIENTS_COUNT stand-by client(s) connected"
+        echo "OK: ${#STANDBY_CLIENTS_ROWS[@]} stand-by client(s) connected"
         EXIT_CODE=0
     else
-        echo "WARNING: current master LSN is not the last sent to stand-by client(s) connected. May be we have some load ?"
+        echo "WARNING: current master LSN is not the last sent to stand-by client(s) connected." \
+            "May be we have some load ?"
         EXIT_CODE=1
     fi
 
     echo "Current master LSN: $CURRENT_LSN"
-    echo -e "$STANDBY_CLIENTS_TXT"
+    IFS=$'\n'
+    echo "${STANDBY_CLIENTS_ROWS[*]}"
     exit $EXIT_CODE
 else
     echo "UNKNOWN - Invalid mode '$EXPECTED_MODE'"

debian/control

@@ -2,7 +2,7 @@ Source: check-pg-streaming-replication
 Section: admin
 Priority: optional
 Maintainer: Debian Zionetrix - check-pg-streaming-replication <debian+check-pg-streaming-replication@zionetrix.net>
-Build-Depends: debhelper (>> 11.0.0)
+Build-Depends: debhelper (>> 11.0.0), findutils, rsync, sed, awk, git, gitdch
 Standards-Version: 3.9.6
 
 Package: check-pg-streaming-replication