DB is not connected

[olsn]

Maybe I'm overlooking something, but it seems your DB is not really connected in the Svelte-App.
That's actually the most difficult part (WITHOUT hardcoding the credentials!) - do you have a solution for that already?

[AWolf81]

@olsn yes, you're right the DB is not connected yet. It's on my to-do list.

There are some ways to create a backend service to connect Svelte to the database.
Initially, I wanted to create an Adonisjs backend but this seems way too complicated (proxy, data fetching, ...)

I think an easy way is to use Hasura so the DB connection from Svelte is pretty straightforward with Apollo Graphql. (There is also a nice console in Hasura to test Graphql queries & check the Postgres database)

I've worked on the Hasura setup but it's not ready yet. The docker setup with Hasura is working. I just need to fix an issue related to Apollo (getting TypeError: this.client.send is not a function from subscriptions-transport-ws).

Once the demo todo app is working, I think I'll create a blog post for it.

Other options to connect to the DB (I haven't tested them):

• Graphql Endpoint by using apollo-server-lambda
• Using Polka and Postgraphile (this was written for Sapper but the same should be possible with Sveltekit).

Update 08.07.2021:
I'm still trying to fix the import of @apollo/client/core. The problem node adapter and Sveltekit needs the Commonjs import but using @apollo/client/core/core.cjs.js throws the following error (during dev server):

ReferenceError: exports is not defined
    at eval (/node_modules/@apollo/client/core/core.cjs.js:3:23)
    at instantiateModule (C:\Users\alexander\GitHub\my_docker_app\app\node_modules\@sveltejs\kit\node_modules\vite\dist\node\chunks\dep-cc49d7be.js:72639:166)
    at processTicksAndRejections (internal/process/task_queues.js:97:5)

I've pushed my current work into branch backend-graphql (with the bug mentioned above).
Database migrations not added - manually creating a todo table with id (primary key, auto int), title (string) & completed (boolean) required on localhost:8080

[AWolf81]

@olsn OK, I've made some progress in the branch backend-graphql.

Todo app is working in dev mode and the build is also working.
The Docker setup works but needs some improvements (see todos below).

There where some issues with @apollo/client and svelte-apollo. I'll review it and add some more details to it.
The main issue was the error Function called outside component initialization as mentioned in this issue #97 / svelte-apollo.

After removing svelte-apollo it is working. I'm using setContext / getContext like Svelte-Apollo and the demo works with @apollo/client directly.
Not sure how to get it to work with svelte-apollo - tried a lot but nothing was working.

Todos

• Add Hasura migrations (at the moment, manually add the todo table)
• Improve the styling and remove the Svelte/kit starter demo code.
• Add more features to the todo app (delete todo & toggle status)
• Revist the Svelte-apollo issue and check the generated code.
• Review the CommonJS issue that we had here too (related svelte/kit issue #928)
• Check the other implementation options
  • Apollo-lambda-server function
  • Polka & Postgraphile

[AWolf81]

OK, I've worked a bit on this (see main branch).

There are also two blog posts to the changes. You can find the links in this Tweet