How to store data in MongoDb using mongoose and async waterfall model

Question

Hello i am new to node and i am trying to save data in mongoose. The problem is that there are 3 collections Units, Building and Section. The Schema of Building is :

var buildingsSchema=new Schema({
    buildingname:String,
    status:String
});

Schema of Section is :

var sectionsSchema=new Schema({
        section_type:String,
        buildings:{ type: Schema.Types.ObjectId, ref: 'buildings' },
        status:String
 });

Schema of Units is :

var unitsSchema=new Schema({
      unit_type:String,
      unit_num:String,
      unit_ac_num:Number,
      buildings:{ type: Schema.Types.ObjectId, ref: 'buildings' },
      sections:{ type: Schema.Types.ObjectId, ref: 'sections' },
      shares:Number
});

in Section there is an Id of Building and in Units there is Id's of both Building & Section

now i have used xlsx plugin to convert uploaded excel file to json by :-

 var wb = XLSX.readFile("uploads/xls/" + req.file.filename);
 data = XLSX.utils.sheet_to_json(wb.Sheets[wb.SheetNames[0]],   {header:1});

and to map it into json object and saving i am using Async Waterfall Model

        for (var index = 1; index < data.length - 1 ; index++) {
        var ele= data[index];
        // console.log(ele);

        var d = {   // this is an object which will hold data 
            record_id: ele[0],
            residenceone_unit_id : ele[1],
            official_unit_id: ele[2],
            building: ele[3],
            unit_type : ele[4],
            section: ele[5],
            shares: ele[6],
            unit_style : ele[7]
        }
        // console.log(d);
        var unt = new Units(); // to save units
        unt = {
            unit_type: d.unit_type,
            unit_num: d.residenceone_unit_id,
            unit_ac_num: d.official_unit_id,
            buildings: '', // empty because need to put id of that particular building
            sections: '', // empty because need to put id of that particular sections
            shares:d.shares
        }
        async.waterfall([
            function (callback) {
                // find building first 
                Buildings.findOne({buildingname : ele.building})
                .exec(function (err,doc) {
                      if (err) {
                          return callback(err);
                      }
                      // if no building then save one 
                      else if (!doc) {
                        // console.log("Building is going to save")
                        var build = new Buildings();
                        build.buildingname = d.building;
                        build.status = "active";
                        build.save(function (err,dc) {
                            if (err) {
                                return callback(err);
                            }
                            else {
                                // assign id of building to unit
                                unt.buildings = dc._id ;
                                callback(null);
                            }
                        })
                      } 
                      else {
                        // if building is there then no need to save assign id of it to units
                        // console.log("Building already exists;")
                         unt.buildings = doc._id ;
                         // execute second function
                         callback(null);
                      } 
                    //   callback(null);
                })
            },
            function (callback) {
                // same as building find section of that building first with building Id and section type
                Sections.findOne({buildings : unt.buildings,section_type: d.section})
                    .exec(function (err,doc) {
                      if (err) {
                          return callback(err);
                      }
                      if (!doc) {
                        // if no section of that building is there then save one
                        // console.log("Section needs to be save")
                        var sect = new Sections();
                        sect.section_type = d.section;
                        sect.buildings = unt.buildings;
                        sect.status = "active";
                        sect.save(function (err,dc) {
                            if (err) {
                                return callback(err);
                            }
                            else {
                                // assign its id to unit
                                // console.log("Section is saved")
                                unt.sections = dc._id; 
                                // execute third function
                                callback(null); 
                            }
                        })
                      } 
                      else {
                          // if there is section of that building id is available than assign id to units
                        // console.log("Section already exists");
                        unt.sections = doc._id;
                         // execute third function 
                         callback(null);  
                      }
                })
            },
            function (callback) {
                // there is no need to seaarch just need to save unit
                // console.log("Units is going to save")
                // console.log(unt);
                unt.save(function (err, doc) {
                    if (err) {

                    } else if (doc){
                        // console.log("Unit Saved");
                        // console.log(doc);

                    }

                })
            }
         ])
    }
}

its working but every time instead of searching of data in mongodb it save everytime. Duplication is the main problem if any other way to save units in mongodb will help me a lot.

Answer 1

first i have save Buildings and section :

async.every(uniqueSection,function (uS,callback) {
      if (uS != undefined) {
          console.log(uS);
            Buildings.findOne({buildingname:uS.building}, function (err,doc) {
                if (doc) {
                    // console.log(doc);
                    Sections.findOne({buildings:doc._id,section_type:uS.section},function (er,sd) {
                        if (sd) {
                            // then dont save
                            console.log(sd);
                        }
                        if (er) {
                            console.log(er);
                        }
                        if (!sd) {
                            // then save
                            var sect = new Sections();
                            sect.buildings = doc._id;
                            sect.section_type = uS.section;
                            sect.status = 'active';
                            sect.save(function (err,st) {
                                if(err) console.log(err);
                                console.log(st);
                            })
                        }
                    })  
                } 
                if (!doc) {
                 if (uS.building != undefined) {
                    var building = new Buildings();
                    building.buildingname = uS.building;
                    building.status = "active";
                    building.save(function (er,dc) {
                        if (dc) {
                            // console.log(dc);
                            Sections.findOne({buildings:dc._id,section_type:uS.section},function (er,sd) {
                                if (sd) {
                                    // then dont save
                                    console.log(sd);
                                }
                                if (er) {
                                    console.log(er);
                                }
                                if (!sd) {
                                    // then save
                                    var sect = new Sections();
                                    sect.buildings = dc._id;
                                    sect.section_type = uS.section;
                                    sect.status = 'active';
                                    sect.save(function (err,st) {
                                        if(err) console.log(err);
                                        console.log(st);
                                    })
                                }
                            })  
                        } 
                        if (er) {
                            console.log(er);
                        }
                    })
                  }
                }
                if (err) {
                    console.log(err);
                }
              })
            }
        })

then i have saved Units by :

   async.waterfall([
                function(callback) {
                    Buildings.findOne({buildingname:d.building}, function (err,doc) {
                        if (doc) {
                            buildingId = doc._id;
                            callback(null, doc);
                        } 
                        if (err) {
                            console.log(err);
                        }
                      })

                },
                function(doc,callback) {
                    Sections.findOne({buildings: buildingId,section_type:d.section},function (er,sd) {
                        if (sd) {
                            sectionId = sd._id;
                           callback(null,doc,sd);  
                        }
                        if (er) {
                            console.log(er);
                        }

                    })  
                },
                function (bld,st,callback) {
                var s = d.shares.replace(",","");
                var unit = {
                    unit_type: d.unit_type,
                    unit_num: d.residenceone_unit_id,
                    unit_ac_num: d.official_unit_id,
                    buildings: bld._id, 
                    sections: st._id,
                    shares: s
                 }
                 Units.findOne(unit,function (err,unt) {
                     if (err) {
                         console.log(err);
                     } 
                     if(unt) {
                         console.log(unt)
                     }
                     if (!unt) {
                        var units = new Units();
                        units.unit_type = d.unit_type;
                        units.unit_num = d.residenceone_unit_id;
                        units.unit_ac_num = d.official_unit_id;
                        units.buildings = bld._id; 
                        units.sections = st._id;
                        units.shares = s;

                        units.save(function (er,doc) {
                            if (er) console.log(er);
                            console.log(doc);
                        }) 
                     }
                 })
                }
            ], function(err) {
                console.log(err)
            });