I found one solution to upload the file to firebase storage without any authentication using this link How to upload objects to Firebase Storage using Postman for testing?
The above-mentioned case works only when my firebase storage looks like this, (Without any security restriction)
allow read, write;
But, Now I want to achieve this with some security restrictions. Is there any way to upload the files to firebase storage by POST URL (Postman) with some security restriction.
I tried to achieve this by
https://firebasestorage.googleapis.com/v0/b/projectName.bucketName.com/o?uploadType=media&name=picture2&auth=uid
But it shows 403 - forbidden error.
There is no public REST API for uploading file to Cloud Storage for Firebase. The end point you're trying to reach is meant for use by the Firebase SDK only, and is neither documented, nor supported for use beyond that.
That said, you may be able to mint a token using the Firebase Authentication REST API, and pass that along to the request you have. But as said, it won't be supported and may change without warning.
The most common approach for REST uploads is through the Google Cloud Storage API, around which the Firebase APIs are a friendly wrapper. But these APIs are meant for access from trusted code, so wouldn't be using the Firebase Authentication UID of your users. The best I can think of is to write a Cloud Function that handles the user authentication and authorization, and then use the Google Cloud Storage Node.js or REST API to upload the file.