partial search with firestore

You can provide partial search [ type ahead facility ] with firestore. It's not that much streight forward and also not feasible in case of large amount of data that has to support the partial search.

Here is just a sample of how you provide partial search with firestore.

Logic behind the search is a custom kind of indexing that enables partial search for us. You need to create a collection of documents called indexes which contains indexes generated for the fields you want to search over.

First reqirement is to create every possible partial search strings.

Below function returns array of the possible indexes generate after chopping out input string character by character.

/* storing searchabel fields */

function _chopped_object(iString) {

  var searchables = {}
  for (i = 0; i < iString.length; i++) {
    var string_part = iString.substr(0, iString.length - i)
    searchables[string_part] = true
  }

  return searchables

}

Output of _chopped_object(manish) will be,
{
manish :true
manis :true
mani :true
man :true
ma :true
m :true
}
That's what we want, Right !
We want tha if we write "m..." it should know we may want to write "manish"

Next question is how to store this index and use it with firebase project.

Create a sperate collection called searchables ( I am saying it searachables 😀, you are free to say anything man ), and store these index documents inside it.

 db.collection("searchables")
   .doc([some-randome-string])
   .set({
   // searchable_index: _chopped_object(sender_profile[key]),
   searchables_index: _chopped_object(sender_profile[key]),

   mapping_value: [mapping_value]

   }).then(() => {

    console.log("Document successfully updated!");

   }).catch((err) => {

    console.log(err)

   });

It may be that it's some confusing, how to use this code.

Example 

We have dictonary of Persons, It includes details like name,phone,email,address

{
    name:"manish",
    phone:[not-going-to-share],
    email:m.champaneri.20@gmail.com,
    address:"something something",
},
{
    name:"mchampnaeri",
    phone:[not-going-to-share],
    email:m.champaneri.20@gmail.com,
    address:"something something",
},
{
    name:"rohan",
    phone:[not-going-to-share],
    email:m.champaneri.20@gmail.com,
    address:"something something",
},

This is our document we are storing in collection of persons

We want to create searchable index of field of name. 
Means, If, I type "m" I should get suggetion of "manish" and "mchampaneri" and after "ma" it should just suggest "manish" 👍.


In this case, 

when you store the person details in document you can create a searchable index in same process.

( I am using nodejs exmpale is in javascript )

function storePersonDeatails(){

var some_radom_key = [ -value- ]  // To store person document 
var some_radom_key2 = [ -value-2 ]  // To store person document search index
 
db.collection("persons")
   .doc( some_radom_key )
   .set({
   personObject
   }).then(() => {   

 // Incase of success full insertion you should create a searchable
        // index on name field for that person
  db.collection("searchables")
    .doc( some_radom_key2 )
    .set({
      searcables_index: _chopped_object(personObject.name),
     mapping_value: some_radom_key  // Same value used as key for document, 
                                                  // so index get attached with the document via key 

    }).then(() => {
     console.log("Document successfully updated!");

    }).catch((err) => {
     console.log(err)

    });

   }).catch((err) => {

    console.log(err)

   });

}

If you see your serachables documents you will find data look like somthing this

searchable Index

UpTo This we just make searchable index now just use it in your search box

here is example code for search box ..

function search(value) {
 db.collection("searchables")
  .where("searchables_index."+ value,"==",true)                 
  .get()
  .then((searchbles)=>{
    searchbles.forEach((item)=>{
    consle.log(item.data())
  })
 }) 
}

Upper code will just try to read the property [value] of the object searchables_index and will get true if it exist.

Hope this was easy to understand. 

If it's not clear,  let me know!

Have a great day !