MongoDB update command

1

I've been away from Rust and have recently been working on a Mongodb micro service. I have hit a problem that has vexed me and not found any good documentation.
I want to update a Mongo document with a variable number of fields. The problem is that the update command is fixed and I can't vary the fields to be updated dynamically. I have tried to build the command but it hasn't worked. Ideally I would like to specify the fields to be updated from a HashMap but not found a way to populate a mongo document and provide a suitable update command. Has anyone done this? I'm sure this is a common requirement but haven't found a solution.

2

This is an example of how you would do it (Sorry for the formatting, I'm on the mobile):

use mongodb::bson::{Bson, Document};

let mut changes: HashMap<String, Bson> = HashMap::new();

// Build your changes
...

// Collect the changes from the hashmap into a MongoDB Document 
let changes_document: Document = changes.into_iter().collect();
            collection
                .update_one(
                    doc! { "your_model_id_field": id.to_string() },
                    doc! { "$set": changes_document },
                    None,
                )
                .await?;
2 Likes
3

I factored your suggestion into my code and it worked!! Many thanks.

4

Since it worked for you, could you please mark their reply as the solution?

5

Thank you, but you marked my reply as the solution. I meant the reply from @firebits.io. I changed the solution to that reply.

1 Like