connect to snowflake returns generic FDW error.

[andre-aura]

Bug report

• I confirm this is a bug with Supabase, not with my own application.
• I confirm I have searched the Docs, GitHub Discussions, and Discord.

Describe the bug

Hi Folks!

I followed the steps described here to create the wrapper and the external tables.

When querying the external table that points to Snowflake I got this error:

ERROR:  HV000: guest fdw error: expected value at line 1 column 1

There is nor more details at postgres logs.

I'm using the same key that I use to connect via dbt.

I can't see any query against snowflake with my user.

Also, I tried to create the same structure mytable from the docs and still no success.

What I'm missing here?

Thanks!

To Reproduce

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4. See error

Expected behavior

A clear and concise description of what you expected to happen.

Screenshots

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System information

• OS: [e.g. macOS, Windows]
• Browser (if applies) [e.g. chrome, safari]
• Version of supabase-js: [e.g. 6.0.2]
• Version of Node.js: [e.g. 10.10.0]

Additional context

Add any other context about the problem here.

[burmecia]

Thanks for reporting this issue. Could you provide more details such as Postgres version, Wrappers version and DDL used to create tables on both Snowflake and Postgres side?

[louis-monier]

I'm facing the same issue. Configuring the Snowflake wrapper is a bit of a nightmare tbh.

[jonathansergio]

Hey @burmecia and @andre-aura! The expected value at line 1 column 1 is a classic serde_json parsing error. It looks like when Snowflake rejects the connection (e.g., auth failure), it returns a non-JSON body (like an HTML error page or plain text). The wrapper is blindly attempting to deserialize this error response into JSON, which panics serde.

I can open a quick PR to inspect the HTTP status code first. If it's a 4xx/5xx, we can read the raw text response and bubble it up to the user via a clean HV000 Postgres error, making it much easier to debug their Snowflake credentials. Does that sound good?

[burmecia]

@jonathansergio yes that's the cause and really appreciate it if you can make the error reporting better!