- Deno uses URLs for dependency management.
- One convention places all these dependent URLs into a local
deps.ts
file. Functionality is then exported out ofdeps.ts
for use by local modules. - Continuing this convention, dev only dependencies can be kept in a
dev_deps.ts
file. - See also Modules
In Deno there is no concept of a package manager as external modules are imported directly into local modules. This raises the question of how to manage remote dependencies without a package manager. In big projects with many dependencies it will become cumbersome and time consuming to update modules if they are all imported individually into individual modules.
The standard practice for solving this problem in Deno is to create a deps.ts
file. All required remote dependencies are referenced in this file and the
required methods and classes are re-exported. The dependent local modules then
reference the deps.ts
rather than the remote dependencies. If now for example
one remote dependency is used in several files, upgrading to a new version of
this remote dependency is much simpler as this can be done just within
deps.ts
.
With all dependencies centralized in deps.ts
, managing these becomes easier.
Dev dependencies can also be managed in a separate dev_deps.ts
file, allowing
clean separation between dev only and production dependencies.
/**
* deps.ts
*
* This module re-exports the required methods from the dependant remote Ramda module.
*/
export {
add,
multiply,
} from "https://x.nest.land/[email protected]/source/index.js";
In this example the same functionality is created as is the case in the
local and remote import examples. But in this case
instead of the Ramda module being referenced directly it is referenced by proxy
using a local deps.ts
module.
Command: deno run example.ts
/**
* example.ts
*/
import { add, multiply } from "./deps.ts";
function totalCost(outbound: number, inbound: number, tax: number): number {
return multiply(add(outbound, inbound), tax);
}
console.log(totalCost(19, 31, 1.2));
console.log(totalCost(45, 27, 1.15));
/**
* Output
*
* 60
* 82.8
*/