mysql as prototype/ POC

plugins/localdump/mysql.sh

@@ -10,12 +10,13 @@
 #
 # 2016-11-10  ah,ds  v0.8  needs to be testet
 # 2017-03-28  .....  v1.0  added restore
-# 2022-01-20         v1.1  fixes with shellcheck
+# 2022-01-20  ah     v1.1  fixes with shellcheck
+# 2022-02-14  ah     v2.0  rewrite with class like functions
 # ================================================================================
 
 if [ -z "$BACKUP_TARGETDIR" ]; then
   echo "ERROR: you cannot start $(basename $0) directly"
-  rc=$rc+1
+  rc+=1
   exit 1
 fi
 
@@ -23,114 +24,224 @@ fi
 # CONFIG
 # --------------------------------------------------------------------------------
 
+mysql_FOUND=0
 SOURCE_DIR=/var/lib/mysql
-MYSQLDUMP=/usr/bin/mysqldump
+
 
 # --------------------------------------------------------------------------------
-# FUNCTIONS
+# PRIVATE FUNCTIONS
 # --------------------------------------------------------------------------------
 
-function doMysqlBackup(){
+# make checks if a service is available on this machine
+# it sets mysql_FOUND as flag
+function mysql._check(){
 
-  create_targetdir
+  j_requireBinary "mysql"             1
+  j_requireBinary "mysqldump"         1
+  j_requireProcess "mysqld|mariadb"   1
 
-  for DATABASE_DIR in $(find $SOURCE_DIR/* -type d -prune);
-  do
-    # DATABASE=`basename $DATABASE_DIR`
-    DATABASE=$(basename "$DATABASE_DIR" | sed "s#\@002d#-#g" )
-    TABLECOUNT=$(find "$DATABASE_DIR"/. -type f -name "*frm" | wc -l)
-    echo "--- database $DATABASE - $TABLECOUNT tables"
-    if [ $TABLECOUNT -gt 0 ]; then
-      echo -n "backup ... "
-      OUTFILE="${BACKUP_TARGETDIR}/$(get_outfile ${DATABASE}).sql"
-      # task 1251 - "--master-data=2" was removed
-      $MYSQLDUMP --opt \
+  if [ ! -d $SOURCE_DIR ]; then
+    echo "INFO: directory $SOURCE_DIR doees not exist."
+    rc=$rc+1
+  fi
+
+  # set flag and reset return code
+  test $rc -eq 0 && mysql_FOUND=1
+  rc=0
+}
+
+# --------------------------------------------------------------------------------
+# PUBLIC FUNCTIONS I :: DB SCHEME - METHODS LOW LEVEL
+# --------------------------------------------------------------------------------
+
+# create a database scheme
+# param  string  name of the dabase scheme
+function mysql.db.create(){
+  local _dbname=$1
+  echo "CREATE DATABASE IF NOT EXISTS ${_dbname};" | mysql
+}
+
+# dump [database] --> [file] 
+# dump a single database into given file
+# param  string  name of database to dump
+# param  string  name of output file
+function mysql.db.dump(){
+
+    local _dbname=$1
+    local _dumpfile=$2
+
+    mysqldump --opt \
               --default-character-set=utf8 \
               --flush-logs \
               --single-transaction \
               --no-autocommit \
-               --result-file="$OUTFILE" \
-               "$DATABASE"
+              --result-file="$_dumpfile" \
+              "$_dbname"
+
+}
+
+# import [file] --> [database] 
+# import a single db dump into a given db
+# param  string  name of file
+# param  string  name of target db scheme
+function mysql.db.import(){
+  local _dumpfile=$1
+  local _dbname=$2
+  zcat "$_dumpfile" | mysql "${_dbname}"
+}
+
+# show a list of existing databases
+function mysql.db.list(){
+  mysql -Ee "show databases ;" | grep "^Database:" | awk '{ print $2 }'
+}
+
+# --------------------------------------------------------------------------------
+# PUBLIC FUNCTIONS II :: HIGH LEVEL
+# --------------------------------------------------------------------------------
+
+# return result is the current service available
+# USAGE: to abort a function if not available:
+# mysql.available || return
+function mysql.available(){
+  typeset -i local _rc=(1-$mysql_FOUND)
+  return $_rc
+}
+
+# make checks if the current service is available on this machine
+# param  bool  flag: silence; if any parameter is set it shows no output
+function mysql.check(){
+
+  if [ -n "$1" ]; then
+    mysql._check >/dev/null 2>&1
+  else
+    echo
+    echo Details:
+    mysql._check
+    echo
+  fi
+}
+
+# start database backup of all schemes of this service
+# no prameters
+function mysql.backup(){
+  # abort if service is not available
+  mysql.available || return
+
+  local _dbname
+  local _outfile
+
+  create_targetdir
+
+  for _dbname in $( mysql.db.list )
+  do
+    echo "--- database $_dbname"
+    echo -n "backup ... "
+    _outfile="${BACKUP_TARGETDIR}/$(get_outfile ${_dbname}).sql"
+
+    mysql.db.dump "$_dbname" "$_outfile"
     fetchrc
 
     # $myrc is last returncode - set in fetchrc
     if [ $myrc -eq 0 ]; then
       echo -n "gzip ... "
-        compress_file "$OUTFILE"
+      compress_file "$_outfile"
     else
+      color error
       echo "ERROR occured - no gzip"
+      color reset
     fi
-      ls -l "$OUTFILE"*
-    fi
+    ls -l "$_outfile"*
     echo
   done
 
 }
 
+# show help
+function mysql.help(){
+  # local _bShow=false
+  # tac "$0" | while read line
+  # do
+  #   if echo $line | grep "^function mysql\.[a-z]" >/dev/null; then
+  #     _bShow = true
+  #   fi
+  #   if echo $line | grep "^# " >/dev/null; then
+  #     _bShow = true
+  #   fi
+  # done
+  cat <<EOHELP
+help for MYSQL-DOT functions
+
+(1) high level functions
+
+  mysql.check [0|1]               check if mysql is available
+  mysql.backup                    backup all databases
+  mysql.restore FILE DBNAME       restore database
+
+(2) functions on database level
+
+  mysql.db.create DBNAME          create database
+  mysql.db.dump DBNAME OUTFILE    dump given database to output file
+  mysql.db.import FILE DBNAME     import file into existing database
+  mysql.db.list                   list existing databases
+
+EOHELP
+}
 # restore database dump file into database
 # param  string  database dump file (gzipped)
 # param  string  optional: database to import; default: database is parsed from file
-function restoreByFile(){
-  sMyfile=$1
-  sMyDb=$2
-
-  if [ -z "$sMyDb" ]; then
-    h2 "analyze dump $sMyfile"
-    sMyDb=$(guessDB $sMyfile)
-    echo "detected db schema from file: [${sMyDb}]"
+function mysql.restore(){
+
+  # abort if service is not available
+  mysql.available || return
+
+  local _infile=$1
+  local _dbname=$2
+
+  if [ -z "$_dbname" ]; then
+    h2 "analyze dump $_infile"
+    _dbname=$(guessDB $_infile)
+    echo "detected db schema from file: [${_dbname}]"
   else
-    echo "db schema from param 2: [${sMyDb}]"
+    echo "db schema from param 2: [${_dbname}]"
   fi
 
   echo
 
-  echo import to "$sMyDb"...
+  echo import to "$_dbname"...
 
   h2 ensure that database exists ...
   color cmd
-  echo "CREATE DATABASE IF NOT EXISTS ${sMyDb};" | mysql
+  # echo "CREATE DATABASE IF NOT EXISTS ${_dbname};" | mysql
+  mysql.db.create "${_dbname}"
   color reset
 
   h2 import ...
-  ls -l "$sMyfile"
-  echo "import to database [${sMyDb}]"
+  ls -l "$_infile"
+  echo "import to database [${_dbname}]"
   color cmd
-  zcat "$sMyfile" | mysql "${sMyDb}"
+  # zcat "$_infile" | mysql "${_dbname}"
+  mysql.db.import "$_infile" "${_dbname}"
   fetchrc
   color reset
 
 }
 
+function mysql.shell(){
+  echo "hi"
+}
 # --------------------------------------------------------------------------------
 # MAIN
 # --------------------------------------------------------------------------------
 
-
-# ----- check requirements
-j_requireBinary "mysql"             1
-j_requireBinary "mysqldump"         1
-j_requireProcess "mysqld|mariadb"   1
-
-if [ ! -d $SOURCE_DIR ]; then
-  echo "INFO: directory $SOURCE_DIR doees not exist."
-  rc=$rc+1
+"${SERVICENAME}".check 1
+if ! "${SERVICENAME}".available; then
+  echo "INFO: service [$SERVICENAME] is not avilable on this machine."
 fi
 
-
-if [ $rc -ne 0 ]; then
-  rc=0
-  echo "SKIP: mysqld seems not to be here"
-else
-  if [ "$1" = "restore" ]; then
-    echo
+action=$1
 shift 1
-    restoreByFile $*
-
-  else
-    doMysqlBackup
-  fi
-fi
+"${SERVICENAME}.$action" $*
 
-echo "$0 $* [mysql] final returncode rc=$rc"
+echo "INFO: $0 $action $* [$SERVICENAME] final returncode rc=$rc"
 
 # --------------------------------------------------------------------------------