equalexperts / mongo-shell-like-query

mongo-shell-like-query

                                          mongo-shell-like-query
                                          ======================


                            Executing mongo-shell-like-query with mongo Java driver

Describe your read queries the same as you do on the mongo client shell, and the library runs it, for both regular queries as well as use of the Mongo aggregation facility

Download a jar for the current release (v1.0) here

#Example

    String query = ”db.users.find( { ‘name’ : ‘John’} )”;

    MongoQueryParser parser = new MongoQueryParser();
    MongoQuery mongoQuery = parser.parse(query, new HashMap());
    BasicDBList results = mongoQuery.execute(mongoDB);

#Features

1. It supports all kinds of read queries (both find as well as aggregation) using various operators

2. It supports query chaining (chain the use of sort, skip, and limit in any order)

3. It tolerates whitespace as: ”db.users.find( { ‘name’ : ‘John’} )” is of course, the same as ”db . users . find ( { ‘name’ : ‘John’ } )”

4. It supports parameterized queries, wherein values can be specified at runtime

       String query = ”db.users.find( { ‘name’ : ‘givenName’} )”
       Map[String,String]  params= new HashMap()
       map.add(“givenName”, “John”)

       MongoQueryParser parser = new MongoQueryParser();
       MongoQuery mongoQuery = parser.parse(query, params);
       BaiscDBList results = mongoQuery.execute(mongoDB);

5. It supports parameterized queries with strongly typed data (Most BSON types are supported)

       String query = ”db.users.find( { salary : ‘sal#Long’} )” 
       Map[String,String]  params= new HashMap()
       map.add(“sal”, “5000”)

       MongoQueryParser parser = new MongoQueryParser();
       MongoQuery mongoQuery = parser.parse(query, params);
       BaiscDBList results = mongoQuery.execute(mongoDB);

Query looks like mongo query string. Providing placeholders is very simple and have consistent pattern. ParameterName#DataType (supported datatypes are String|Boolean|Integer|Double|ObjectId)

For more examples checkout ‘src/test/resources’ folder and MongoQueryIntegrationTest

6. It supports both scala and java api

#Usage

1. Download the .jar file and add it to your project

2.Use library:

a) Java API

  String query = "db.users.find( { 'role' : 'manager'} )";
  DB mongoDB = new MongoClient().getDB("your-db-name");

  MongoQuery mongoQuery = new   MongoQueryParser().parse(query, new HashMap());
  BasicDBList results = mongoQuery.execute(mongoDB);
  System.out.println(results.size());

b) Scala API

  val query = "db.users.find( { 'role' : 'manager'} )"
  val mongoConn = MongoConnection()
  val mongoDB = mongoConn("your-db-name")
  
  val mongoQuery: MongoQuery = parser.parse(query, Map())
  val results = mongoQuery.execute(mongoDB)
  println(results.size)

END-OF-FILE

mongo-shell-like-query's Issues

http://49.248.27.91:9090/nexus/ Maven repository needs access credentials

Can you please host this utility on a publicly available repository or at-least provide a jar file as a download on the github project site.

Please provide an example using Aggregation Query

I've been trying to use this library to perform an aggregation query but I'm having difficulty doing so. Could you provide an example of how to execute an aggregation query using $match & $projection in java?

Project's support

Hi team,

do you support this project now?

Allow aggregate method with opt

            MongoQueryParser parser = new MongoQueryParser();
            MongoQuery mongoQuery = parser.parse(longQuery, new HashMap());
            BasicDBList dbObjList = mongoQuery.execute(db);

Query is an aggregation: db.events.aggregate([....])

I have an exception: Caused by: com.mongodb.MongoCommandException: Command failed with error 16945: 'Exceeded memory limit for $group, but didn't allow external sort. Pass allowDiskUse:true to opt in.

When i try to pass it like: db.events.aggregate([....],{ allowDiskUse: true }) then i have an exception:
java.lang.RuntimeException: invalid query
at com.ee.dynamicmongoquery.MongoQueryParser.parse(MongoQueryParser.scala:31)
at com.ee.dynamicmongoquery.MongoQueryParser.parse(MongoQueryParser.scala:27)
......
Caused by: java.lang.ClassCastException: null

How can i pass allowDiskUse:true to query?

Map / Reduce support?

Would it be possible to add map/reduce to the supported command sets.

I'd really like to be able to spam all the map/reduce commands in a single string.

m = function () { emit(this.field, 1);}; r = function (k, vals) {return Array.sum(vals);}; res = db.mycollection.mapReduce(m, r, { out : "temp_col1" }); db.temp_col1.find({value: {$gt: 1}}); db.temp_col1.drop();

It would be ok if the format weren't the same as the mongo shell, but required some special flags to define functions.

findOne() support

This is a pretty minor/low priority request, but is it any effort to add findOne() to the allowable queries. It's one we run from the normal shell all the time. I assume I can do the same with limit, but this is meant to be shell-like-queries.