How to specify model schema when referencing another dbt project as a package? (dbt multi-repo setup) - dbt

Question

We're using a dbt multi-repo setup with different projects for different business areas. We have several projects, something like this:
dbt_dwh
dbt_project1
dbt_project2
The dbt_dwh project contains models which we plan to reference in projects 1 and 2 (we have ~10 projects that would reference the dbt_dwh project) by way of installing git packages. Ideally, we'd like to be able to just reference the models in the dbt_dwh project (e.g.
SELECT * FROM {{ ref('dbt_dwh', 'model_1') }}). However, each of our projects sits in it's own database schema and this causes issue upon dbt run because dbt uses the target schema from dbt_project_x, where these objects don't exist. I've included example set-up info below, for clarity.
packages.yml file for dbt_project1:
packages:
- git: https://git/repo/url/here/dbt_dwh.git
revision: master
profiles.yml for dbt_dwh:
dbt_dwh:
target: dwh_dev
outputs:
dwh_dev:
<config rows here>
dwh_prod:
<config rows here>
profiles.yml for dbt_project1:
dbt_project1:
target: project1_dev
outputs:
project1_dev:
<config rows here>
project1_prod:
<config rows here>
sf_orders.sql in dbt_dwh:
{{
config(
materialized = 'table',
alias = 'sf_orders'
)
}}
SELECT * FROM {{ source('salesforce', 'orders') }} WHERE uid IS NOT NULL
revenue_model1.sql in dbt_project1:
{{
config(
materialized = 'table',
alias = 'revenue_model1'
)
}}
SELECT * FROM {{ ref('dbt_dwh', 'sf_orders') }}
My expectation here was that dbt would examine the sf_orders model and see that the default schema for the project it sits in (dbt_dwh) is dwh_dev, so it would construct the object reference as dwh_dev.sf_orders.
However, if you use command dbt run -m revenue_model1 then the default dbt behaviour is to assume all models are located in the default target for dbt_project1, so you get something like:
11:05:03 1 of 1 START sql table model project1_dev.revenue_model1 .................... [RUN]
11:05:04 1 of 1 ERROR creating sql table model project1_dev.revenue_model1 ........... [ERROR in 0.89s]
11:05:05
11:05:05 Completed with 1 error and 0 warnings:
11:05:05
11:05:05 Runtime Error in model revenue_model1 (folder\directory\revenue_model1.sql)
11:05:05 404 Not found: Table database_name.project1_dev.sf_orders was not found
I've got several questions here:
How do you force dbt to use a specific schema on runtime when using dbt ref function?
Is it possible to force dbt to use the default parameters/settings for models inside the dbt_dwh project when this Git repo is installed as a package in another project?
Some points to note:
All objects & schemas listed above sit in the same database
I know that many people recommend mono-repo set-up to avoid exactly this type of scenario, but switching to a mono-repo structure is not feasible right now, as we are already fully invested in multi-repo setup
Although it would be feasible to create source.yml files in each of the dbt projects to reference the output objects of the dbt_dwh project, this feels like duplication of effort and could result in different versions of the same sources.yml file across projects
I appreciate it is possible to hard-code the output schema in the dbt config block, but this removes our ability to test in dev environment/schema for dbt_dwh project

Answer 1

I managed to find a solution so I'll answer my own question in case anybody else runs up against the same issue. Unfortunately this is not documented anywhere that I can find, however, a throw-away comment in the dbt Slack workspace sparked an idea that allowed me to find the/a solution (I'll post the message if I manage to find it again, to give credit where it's due).
To fix this is actually very simple, you just need to add the project being imported to your profiles.yml file and specify the schema. For our use case this is fine as we only have 1 schema we use.
profiles.yml for dbt_project1:
models:
db_project_1:
outputs:
project1_dev:
<configs here>
project1_prod:
<configs here>
dbt_dwh:
+schema: [[schema you want these models to run into]]
<configs here>
The advantages with this approach are:
When you generate/serve dbt docs it allows you to see the upstream lineage from the upstream project
If there are any upstream dependencies in your upstream project you can run this using dbt run -m +model_name (this can be super handy)
If you don't want this behaviour then you can use dbt run -m +model_name --exclude dbt_dwh (for example) to prevent models in your upstream project from running.
I haven't yet figured out if it is possible to use the default parameters/settings for models inside the upstream project (in this case dbt_dwh) but I will edit this answer if I find a way.