Create MongoDB replica sets, shards, and test data

ShardTest.ps1

# Powershell Script for creating a 3x5 shard cluster
# Based on Mongo University M101 lecture, "Building a Shared Environemnt" https://youtu.be/dn45G2yw20A

$rootpath = "/temp/mongoshards/"

new-module  -scriptblock {function report($text) {
write-output $("-" * $text.length)
write-output $text
write-output $("-" * $text.length)
write-output ""
}}  | Out-Null

report "Remove temporary directory"

remove-item $rootpath -recurse 

report "Create data directories"

new-item -type directory -path $rootpath | Out-Null

report "Create mongod instances"

$shards = 0..2
foreach ($shard in $shards)
{
   
  $rss = 0..2
  foreach ($rs in $rss)
  {
    $dbpath = "$rootpath/data/shard${shard}/r${rs}"
    new-item -type directory -path $dbpath | Out-Null
  
    # Start mongod processes
    $port = 30000 + ($shard * 3) + $rs
    $args = "--replSet s$shard --logpath $rootpath/s${shard}_r${rs}.log --dbpath $dbpath --port $port --oplogSize 64 --smallfiles"
    $process = start-process mongod.exe $args  
  }
  
  report "Configure replica sets"
 
  
  $port1 = 30000 + $shard * 3
  $port2 = 30000 + $shard * 3 + 1     
  $port3 = 30000 + $shard * 3 + 2
     
  $configBlock = "{_id: ""s$shard"", members: [ {_id:0, host:""localhost:$port1""}, {_id:1, host:""localhost:$port2""}, {_id:2, host:""localhost:$port3""}]}"
  echo "rs.initiate($configBlock)" | mongo --port $port1  
 
} 
 
report "Check PRIMARY elected for each replica set"
 
while ($True)
{
  $response1 = (echo "rs.status()" | mongo -port 30000)
  $response2 = (echo "rs.status()" | mongo -port 30003)
  $response3 = (echo "rs.status()" | mongo -port 30006)
  

  if (($response1 -clike "*PRIMARY*") -and ($response2 -clike "*PRIMARY*") -and ($response3 -clike "*PRIMARY*")) {
    break
   }
  Start-Sleep -s 1
  Write-Output "."
}
 
 report "PRIMARY elected"
  
 report "Create config servers"
 
$cfg_a = "${rootpath}/data/config_a"
$cfg_b = "${rootpath}/data/config_b"
$cfg_c = "${rootpath}/data/config_c"

new-item -type directory -path $cfg_a
new-item -type directory -path $cfg_b
new-item -type directory -path $cfg_c

$arg_a = "--dbpath $cfg_a --logpath ${rootpath}/cfg-a.log --configsvr --smallfiles --port 40000"
$arg_b = "--dbpath $cfg_b --logpath ${rootpath}/cfg-b.log --configsvr --smallfiles --port 40001"
$arg_c = "--dbpath $cfg_c --logpath ${rootpath}/cfg-c.log --configsvr --smallfiles --port 40002"

start-process mongod $arg_a
start-process mongod $arg_b
start-process mongod $arg_c

report "Config servers up"

report "Launch mongos"
 
$args_s = "--port 50000 --logpath ${rootpath}/mongos-1.log --configdb localhost:40000,localhost:40001,localhost:40002"
start-process mongos $args_s

report "Check mongos online on port 50000"

while($true)
{
   
  $output = echo "" |  mongo localhost:50000 2> null
 
  if (-not ($output -like "*failed*")) {break} 
  
  Start-Sleep -s 1
  Write-Output "."
}
report "Mongos avaiable at port 50000"

report "Configure shards"

echo "db.adminCommand( { addshard: ""s0/localhost:30000"" })" | mongo  --quiet  --port 50000 

echo "db.adminCommand( { addshard: ""s1/localhost:30003"" })" | mongo  --quiet --port 50000 

echo "db.adminCommand( { addshard: ""s2/localhost:30006"" })" | mongo  --quiet --port 50000 

echo "db.adminCommand( { enableSharding:""school"" })" | mongo --port 50000 

echo "db.adminCommand( { shardCollection:""school.students"", key:{student_id:1} })" | mongo --port 50000 



report "Generate 100,000 documents" 

$mongoUniversityScript = "db=db.getSiblingDB(`"school`");
types = ['exam', 'quiz', 'homework', 'homework'];
// 10,000 students
for (i = 0; i < 10000; i++) {

    // take 10 classes
    for (class_counter = 0; class_counter < 10; class_counter ++) {
	scores = []
	    // and each class has 4 grades
	    for (j = 0; j < 4; j++) {
		scores.push({'type':types[j],'score':Math.random()*100});
	    }

	// there are 500 different classes that they can take
	class_id = Math.floor(Math.random()*501); // get a class id between 0 and 500

	record = {'student_id':i, 'scores':scores, 'class_id':class_id};
	db.students.insert(record);

    }

}"

echo $mongoUniversityScript | mongo --port 50000 --quiet

report "Total records, records in shard 1, 2, and 3"

echo "db.students.count()" | mongo school --port 50000

echo "db.students.count()" | mongo school --port 30000

echo "db.students.count()" | mongo school --port 30003

echo "db.students.count()" | mongo school --port 30006

report "sh.status() output" 

echo "sh.status()" | mongo --port 50000