How to execute mongo commands through shell scripts

Question

I want to execute mongo commands in shell script  e g  in a script test sh      bin sh mongo myDbName db mycollection findOne   show collections   When I execute this script via   test sh  then the connection to MongoDB is established  but the following commands are not executed   How to execute other commands through shell script test sh

User · Answer

Put your mongo script into a  js file   Then execute mongo  lt  yourFile js  Ex   demo js    file has your script  use sample    db name show collections   keep this file in  c  db-scripts   Then in cmd prompt go to  c  db-scripts   C  db-scripts gt mongo  lt  demo js   This will execute the code in mongo and shows the output  C  db-scripts gt mongo  lt  demo js Mongo shell version  3 0 4 Connecting to  test switched to db sample users     collection name tasks     collection name bye C  db-scripts gt

User · Answer

As suggested by theTuxRacer  you can use the eval command  for those who are missing it like I was  you can also add in your db name if you are not trying to preform operation on the default db   mongo  lt dbname gt  --eval  printjson db something find

User · Answer

Put this in a file called test js   db mycollection findOne   db getCollectionNames   forEach function collection      print collection         then run it with mongo myDbName test js

User · Answer

You can also evaluate a command using the --eval flag  if it is just a single command   mongo --eval  printjson db serverStatus       Please note  if you are using Mongo operators  starting with a   sign  you ll want to surround the eval argument in single quotes to keep the shell from evaluating the operator as an environment variable   mongo --eval  db mycollection update   name   foo     set   this   that       myDbName   Otherwise you may see something like this   mongo --eval  db test update    name     foo      set    this     that         gt  E QUERY    SyntaxError  Unexpected token

User · Answer

How about this   echo  db mycollection findOne      mongo myDbName echo  show collections    mongo myDbName

User · Answer

The shell script below also worked nicely for me    definite had to use the redirect that Antonin mentioned at first    that gave me the idea to test the here document   function testMongoScript       mongo  lt  lt EOF     use mydb     db leads findOne       db leads find   count   EOF

User · Answer

I use the  heredoc  syntax  which David Young mentions   But there is a catch      usr bin sh  mongo  lt db gt   lt  lt EOF db  lt collection gt  find     fieldName     exists  true       forEach  printjson    EOF   The above will NOT work  because the phrase   exists  will be seen by the shell and substituted with the value of the environment variable named  exists    Which  likely  doesn t exist  so after shell expansion  it becomes       usr bin sh  mongo  lt db gt   lt  lt EOF db  lt collection gt  find     fieldName      true       forEach  printjson    EOF   In order to have it pass through you have two options   One is ugly  one is quite nice   First  the ugly one  escape the   signs      usr bin sh  mongo  lt db gt   lt  lt EOF db  lt collection gt  find     fieldName      exists  true       forEach  printjson    EOF   I do NOT recommend this  because it is easy to forget to escape   The other option is to escape the EOF  like this      usr bin sh  mongo  lt db gt   lt  lt  EOF db  lt collection gt  find     fieldName     exists  true       forEach  printjson    EOF   Now  you can put all the dollar signs you want in your heredoc  and the dollar signs are ignored   The down side  That doesn t work if you need to put shell parameters variables in your mongo script   Another option you can play with is to mess with your shebang   For example      bin env mongo  lt some mongo stuff gt    There are several problems with this solution    It only works if you are trying to make a mongo shell script executable from the command line   You can t mix regular shell commands with mongo shell commands   And all you save by doing so is not having to type  mongo  on the command line      reason enough  of course  It functions exactly like  mongo  lt some-js-file gt   which means it does not let you use the  use  lt db gt   command      I have tried adding the database name to the shebang  which you would think would work   Unfortunately  the way the system processes the shebang line  everything after the first space is passed as a single parameter  as if quoted  to the env command  and env fails to find and run it     Instead  you have to embed the database change within the script itself  like so      bin env mongo db   db getSiblingDB   lt db gt      lt your script gt    As with anything in life   there is more than one way to do it

User · Answer

Create a script file  write commands      bin sh mongo  lt  file js   In file js write your mongo query   db collection find   myValue  null   count

User · Answer

mongo db name --eval  db user info find   forEach function o   print o  id

User · Answer

When using a replicaset  writes must be done on the PRIMARY  so I usually use syntax like this which avoids having to figure out which host is the master   mongo -host myReplicaset anyKnownReplica

User · Answer

This works for me under Linux   mongo  lt  script js

User · Answer

In case you have authentication enabled   mongo -u username -p password --authenticationDatabase auth db name  lt  your script js

User · Answer

In my setup I have to use    mongo --host  the server ip port  databaseName theScript js

User · Answer

--shell flag can also be used for javascript files   mongo --shell  path to jsfile test js

User · Answer

Single shell script solution with ability to pass mongo arguments  --quiet  dbname  etc       usr bin env -S mongo --quiet localhost 27017 test  cur   db myCollection find      while cur hasNext        printjson cur next         The -S flag might not work on all platforms

User · Answer

Thank you printf   In a Linux environment  here s a better way to have only one file run the show   Say you have two files  mongoCmds js with multiple commands   use someDb db someColl find     and then the driver shell file  runMongoCmds sh  mongo  lt  mongoCmds js   Instead  have just one file  runMongoCmds sh containing  printf  use someDb ndb someColl find      mongo   Bash s printf is much more robust than echo and allows for the  n between commands to force them on multiple lines

User · Answer

There is an official documentation page about this as well   Examples from that page include   mongo server 27017 dbname --quiet my commands js mongo test --eval  printjson db getCollectionNames

User · Answer

mongo  lt  lt EOF use  lt db name gt  db getCollection   lt collection name gt    find     EOF

User · Answer

Recently migrated from mongodb to Postgres  This is how I used the scripts   mongo  lt  scripts js  gt  inserts sql   Read the scripts js and output redirect to inserts sql   scripts js looks like this  use myDb  var string    INSERT INTO table a  b  VALUES   db getCollection  collectionName   find     forEach function  object        string           String object description            object name              print string substring 0  string length - 1           inserts sql looks like this  INSERT INTO table a  b  VALUES  abc    Alice      def    Bob      ghi    Claire

User · Answer

In my case  I can conveniently use  n as separator for the next mongo command I want to execute then pipe them to mongo  echo   use your db ndb yourCollection find      mongo

User · Answer

If you want to handle it with one line it s an easy way    file sh -- gt  db EXPECTED COLLECTION remove   id  1234   cat file sh   mongo  lt EXPECTED COLLECTION gt

[mongodb] How to execute mongo commands through shell scripts?

Examples related to mongodb

Examples related to bash

Examples related to shell

Examples related to sh