moodring•3mo ago

Local Deno package imports: Use package's deno.json config "exports" map?

I'm working in a Deno workspace where the outer workspace deno.json references a project within (at some sub-dir path). - The project's deno.json uses the "exports" option to map "." to "./src/mod.ts". - The workspace root's deno.json then references this directory in the "imports" map, from "package-a" to "./package-a".

[workspace-root]/
  [project-a]/
    src/
      mod.ts - References ``
    deno.json - Maps export "." to "src/mod.ts"
  src/
    main.ts - References 
  deno.json - Maps import "project-a" to "./project-a"

[workspace-root]/
  [project-a]/
    src/
      mod.ts - References ``
    deno.json - Maps export "." to "src/mod.ts"
  src/
    main.ts - References 
  deno.json - Maps import "project-a" to "./project-a"

I would infer/expect (incorrectly?) based on Deno + JSR's import docs, that the outer workspace's import would use the values found in project-a's "exports" map. Running the project returns the following error:

$ deno run -A --unstable-ffi ./src/main.tsx
error: Import 'file:///Users/[user]/[workspace-root]/[project-a]' failed.
    0: Is a directory (os error 21)
error: Uncaught (in promise) ProcessError: Command failed.
Exit code: 1
            await $`deno run -A --unstable-ffi ./src/main.tsx`;
                   ^

$ deno run -A --unstable-ffi ./src/main.tsx
error: Import 'file:///Users/[user]/[workspace-root]/[project-a]' failed.
    0: Is a directory (os error 21)
error: Uncaught (in promise) ProcessError: Command failed.
Exit code: 1
            await $`deno run -A --unstable-ffi ./src/main.tsx`;
                   ^

Is my assumption incorrect? Is there something else wrong with my setup? Ultimately, what I'd like is to respect the package's "exports" values, such that 1) I can import with a short specifier, and 2) I can reference either a local directory or the package on JSR without changing any import code.

9 Replies

moodringOP•3mo ago

Note: I'm seeing that I might be able to just reference a singular export path and then reference that file directly in the imports, but I'd prefer to keep my existing exports structure (if possible). I also wonder about other unintended side-effects related to bypassing the package level configs.

bartlomieju•3mo ago

@dsherret can you advise here?

dsherret•3mo ago

deno.json - Maps import "project-a" to "./project-a"

That will map it to the directory, which isn't supported. If you give project-a a name like @some-scope/project-a in the deno.json then you should be able to just import it with that bare specifier anywhere in the workspace

dsherret•3mo ago

if you ignore the squiggles on project-a, this works

dsherret•3mo ago

i opened https://github.com/denoland/deno/pull/29463 to remove the warning that's shown there

moodringOP•3mo ago

Perfect, thank you so much! Seems this works great for projects within the same workspace. An aside: I have a similar use-case, importing packages from a local directory which is adjacent to the root workspace; i.e., two workspaces next to each other, where workspace-a imports workspace-b. As local directory imports aren't supported, I'm just referencing the necessary modules directly in the workspace-a import map. Is this the recommended way to do things?

dsherret•3mo ago

if you have a workspaces outside another workspace you can probably use the "patch" feature (soon to be renamed "link" I think) https://github.com/denoland/deno/issues/25110

GitHub

Tracking: stabilization of "patch" feature · Issue #25110 · denol...

// deno.json { "patch": [ "../some-package-or-workspace" ] } #25068 Questions: Is "patch" an ok name? Isn't it confusing with the idea of "patching a package&...

dsherret•3mo ago

that will link in the specified package or workspace's packages in the current workspace

moodringOP•3mo ago

Thanks @dsherret, this is working great! Though, for anyone else following along (or finding this down the line): Workspaces apparently require package names to be formatted as @[namespace]/[package], which was unclear (to me). Building "workspace a" with the "patch" definition (apparently) doesn't alert to warnings in "workspace b" (the patch target workspace). Building the patched workspace directly does provide warning feedback, but before doing so I found myself looking for documentation explaining other unclear error messages about missing exports.

Local Deno package imports: Use package's deno.json config "exports" map?

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