Backup script for mongodb

mongodb-backup.sh

@@ -0,0 +1,111 @@
+#!/bin/bash
+
+# Use script by passing username, password and path: ./mongodb-backup.sh USER PASSWORD PATH
+
+mongo_host="localhost"
+mongo_port="27017"
+mongo_user=$1
+mongo_password=$2
+mongo_auth_db="admin"
+backup_folder_root=$3
+
+# set the threshold date as two weeks ago
+threshold_date=$(date --date="-2 weeks" +%Y%m%d)
+
+# set the backup parent directory name as today's date in YYYYMMDD format
+backup_parent_dir=$(date +%Y%m%d)
+
+# set the backup child directory name as the current time in HH:MM format
+backup_child_dir=$(date +%H:%M:%S)
+
+# set the full backup path name as a variable
+backup_path="${backup_folder_root}/$backup_parent_dir/$backup_child_dir"
+
+# create the backup parent directory if it doesn't exist
+mkdir -p "$backup_path"
+
+# loop through all directories in the parent directory
+for dir in */; do
+    # check if the directory name is in YYYYMMDD format
+    if [[ "$dir" =~ ^[0-9]{8}/$ ]]; then
+        # get the directory name as a date string
+        dir_date=$(echo "$dir" | sed 's/\///')
+        # compare the directory date to the threshold date
+        if [ "$dir_date" -lt "$threshold_date" ]; then
+            # delete the directory and its contents
+            echo "Deleting $dir"
+            # rm -rf "$dir"
+        fi
+    fi
+done
+
+# create the backup child directory if it doesn't exist
+mkdir -p "$backup_path"
+
+# Connect to MongoDB
+
+mongo_uri="mongodb://${mongo_user}:${mongo_password}@${mongo_host}:${mongo_port}/${mongo_auth_db}"
+mongo_cmd="mongo ${mongo_uri} --quiet"
+
+# Get information about all current databases and collections
+declare -A db_current
+db_collection_info=$($mongo_cmd --eval 'db.getMongo().getDBNames().forEach(function(dbName){var database = db.getSiblingDB(dbName);database.getCollectionNames().forEach(function(collName){var size=database.getCollection(collName).stats().size;print(dbName + "-" + collName + "=" + size);});});')
+while read -r line; do
+    # split line by equals sign to get key and value
+    key=${line%=*}
+    value=${line#*=}
+    # add key-value pair to dictionary
+    db_current["$key"]="$value"
+done <<< "$db_collection_info"
+
+# Get data from previous backup
+declare -A db_previous
+# read key-value pairs from file and add to array
+while IFS='=' read -r key value; do
+    db_previous["$key"]="$value"
+done < "${backup_folder_root}/db_info.txt"
+
+# We need the previous backup folder... 
+# get a sorted list of directory names
+dirlist=$(find ${backup_folder_root}/$backup_parent_dir -maxdepth 1 -type d -printf '%f\n' | sort -n)
+# find the index of the current directory name
+index=$(echo "$dirlist" | grep -n "$backup_child_dir" | cut -d: -f1)
+prev_index=$((index - 1))
+prev_dirname=$(echo "$dirlist" | sed "${prev_index}q;d")
+prev_path="${backup_folder_root}/$backup_parent_dir/$prev_dirname"
+
+echo "Previous directory name: $prev_dirname"
+echo "Current directory name: $backup_child_dir"
+
+# if previous folder doesn't exist, or is empty, do a full backup
+if [ -z "$prev_dirname" ] || [ ! -d "${prev_path}" ] || [ -z "$(find "${prev_path}" -mindepth 1 -print -quit)" ]; then
+  mongodump --username "$mongo_user" --password "$mongo_password" --authenticationDatabase admin --out "$backup_path"
+else
+  # otherwise only backup what has changed.
+  # Get the list of db folders in previous backup folder
+    for folder_path in "$prev_path"/*/; do
+      database_folder=$(basename "$folder_path")
+      for collection_path in "$folder_path"/*.bson; do
+        filename=$(basename "$collection_path")
+        collection_name="${filename%.*}"
+        collection_key="${database_folder}-${collection_name}"
+        # Check size of previous backed-up collection
+        if test "${db_previous["$collection_key"]}" = "${db_current["$collection_key"]}"; then
+          # Collection size is the same
+          # Move the backup to the new folder
+          mkdir -p "${backup_path}/${database_folder}"          
+          mv ${prev_path}/${database_folder}/${collection_name}.* ${backup_path}/${database_folder}
+          # Create symbolic link from files in previous folder to newest one
+          ln -sf ${backup_path}/${database_folder}/${collection_name}.bson ${prev_path}/${database_folder}/${collection_name}.bson
+          ln -sf ${backup_path}/${database_folder}/${collection_name}.metadata.json ${prev_path}/${database_folder}/${collection_name}.metadata.json
+        else
+          # Collection size has changed - backup new data
+          mongodump --username "$mongo_user" --password "$mongo_password" --authenticationDatabase admin --out "$backup_path" --db="$database_folder" --collection="$collection_name"
+        fi
+      done
+    done
+fi
+
+# Write current data info to file for next time
+echo "${db_collection_info}" > "${backup_folder_root}/db_info.txt"
+

mongodb-status.sh

@@ -6,14 +6,15 @@
 
 LOG_FILE="/root/scripts/logs/mongodb-status.log"
 
-status=$(sudo systemctl status mongod)
+status=$(sudo systemctl status mongodb.service)
 current_time=$(date +"%Y-%m-%d %T")
 
 if echo "$status" | grep -qE "Active: running|Active: active"; then
   echo "[$current_time] Success $(echo "$status" | grep "Main PID")" >> $LOG_FILE
 else
   echo "[$current_time] Failed" >> $LOG_FILE
-  sudo service mongod restart
+  sudo systemctl restart mongodb.service
+  echo "MongoDB database service has stopped running, and was restarted" | mail -s "MongoDB down" tessmarka@gmail.com
 fi
 
 lines=$(wc -l < $LOG_FILE)