#!/bin/sh

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#  to you under the Apache License, Version 2.0 (the
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#  
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# Configure a postgresql hot standby server
here=`echo "import os; print os.path.realpath('$0')" | python`; here=`dirname $here`
mkdir -p $1
root=`echo "import os; print os.path.realpath('$1')" | python`

# Server address
addr=$2
if [ "$addr" = "" ]; then
    host="localhost"
    listen="*"
    port="5432"
else
    host=`$here/../../modules/http/httpd-addr ip $addr`
    if [ "$host" = "" ]; then
        host="localhost"
        listen="*"
    else
        listen=$host
    fi
    port=`$here/../../modules/http/httpd-addr port $addr`
fi
bport=`expr $port + 1000`

# Master server address
if [ "$3" = "" ]; then
    mhost="localhost"
    mport="5432"
    mhttpport="80"
else
    mhost="$3"
    mport="$4"
    mhttpport="$5"
fi

pgsql_prefix=`cat $here/pgsql.prefix`
pgbouncer_prefix=`cat $here/pgbouncer.prefix`

user=`id -un`

mkdir -p $root/sqldb/data
chmod 700 $root/sqldb/data
mkdir -p $root/sqldb/archive
mkdir -p $root/sqldb/backup

if [ -f "$root/sqldb/log.conf" ]; then
    pgsql_log=`cat $root/sqldb/log.conf`
else
    mkdir -p $root/logs
    pgsql_log="cat >>$root/logs/postgresql"
fi
mkdir -p $root/sqldb
mkdir -p $root/sqldb/tmp
echo $pgsql_log >$root/sqldb/logger

# Initialize from a backup of the master
if [ ! -f $root/sqldb/data/postgresql.conf ]; then
    uname=`uname -s`
    if [ $uname = "Darwin" ]; then
        tar=gnutar
    else
        tar=tar
    fi
    (curl -L -# http://$mhost:$mhttpport/pgsql-restore | $tar -C $root/sqldb -xz) 2>&1 | grep -v "100.0%" | sh $root/sqldb/logger
    mkdir -p $root/sqldb/data/pg_xlog/archive_status
    chmod 700 $root/sqldb/data/pg_xlog/archive_status
fi

# Generate server configuration
cp $root/sqldb/data/postgresql-init.conf $root/sqldb/data/postgresql.conf
cat >>$root/sqldb/data/postgresql.conf <<EOF

# Generated by: pgsql-standby-conf $*

# Setup logging
log_min_messages = NOTICE
log_min_error_statement = NOTICE
log_min_duration_statement = -1
log_checkpoints = on
log_connections = off
log_disconnections = off
log_duration = off
log_lock_waits = on
log_statement = none

# Listen
listen_addresses = '$listen'
port = $port
unix_socket_directory = '$root/sqldb/tmp'

# Setup archival
archive_mode = on
archive_command = '$here/pgsql-archive $root $host $bport %p %f'

# Setup hot standby with streaming replication
wal_level = hot_standby
max_wal_senders = 5
wal_keep_segments = 32

# Enable hot standby
hot_standby = on

EOF

# Generate recovery configuration
cat >$root/sqldb/data/recovery.conf << EOF
# Generated by: pgsql-standby-conf $*

# Start in standby mode
standby_mode = 'on'
primary_conninfo = 'host=$mhost port=$mport user=standby application_name=$host:$port'

# Failover
trigger_file = '$root/sqldb/failover'

restore_command = 'curl -L -# http://$mhost:$mhttpport/pgsql-archive/%f -o "%p" 2>&1 | grep -v "100.0%"'

EOF

# Generate database restore script
mkdir -p $root/sqldb/scripts
cat >$root/sqldb/scripts/restore <<EOF
#!/bin/sh
$here/pgsql-restore $root
EOF
chmod 700 $root/sqldb/scripts/restore

# Configure HTTPD to serve backup and archive files
if [ -f "$root/conf/httpd.conf" ]; then
    cat >>$root/conf/httpd.conf <<EOF
# Generated by: pgsql-standby-conf $*

# Serve PostgreSQL backup and WAL archive files
ScriptAlias /pgsql-restore "$root/sqldb/scripts/restore"
Alias /pgsql-archive "$root/sqldb/archive"

EOF

fi

# Configure PgBouncer
mkdir -p $root/logs
id=`id -un`
cat >$root/sqldb/data/pgbouncer.conf <<EOF

[databases]
db = host=$host port=$port dbname=db user=bouncer

[pgbouncer]
listen_addr = $listen
listen_port = $bport
unix_socket_dir =
auth_type = trust
auth_file=$root/sqldb/data/pgbouncer-auth.conf
logfile = $root/logs/pgbouncer
pidfile = $root/logs/pgbouncer.pid
max_client_conn = 1000
pool_mode = transaction
server_reset_query =
default_pool_size = 50
min_pool_size = 5
reserve_pool_size = 5
log_connections = 0
log_disconnections = 0
stats_period = 3600
admin_users = $id

EOF

cat >$root/sqldb/data/pgbouncer-auth.conf <<EOF
"$id" "password"

EOF