Dependencies are an intrinsic part of every software project.
The Dependencies component is responsible to track the list of dependencies a
project has, and then used by project types as the model for rendering
project-specific dependency manifests such as the dependencies section
package.json files.
To add a dependency you can use a project-type specific API such as
nodeProject.addDeps() or use the generic API of project.deps:
project.deps.addDependency(dep, type);
By default, npx projen will automatically install dependencies in your
project if they are not already installed.
The first argument (dep) is a string in the form MODULE[@VERSION] where
MODULE is the package-manager specific name of the dependency (i.e. for node
projects, this is the npm module name) and VERSION is an optional semantic
version requirement (e.g. @^7).
The second argument (type) defines the dependency type and is one of:
DependencyType.RUNTIME: The dependency is required for the program/library during runtime.DependencyType.PEER: The dependency is required at runtime but only a single
copy of the module must exist in the dependency closure of the consumer. In
most package managers (PyPI, NuGet, Maven) there is no difference between
runtime and peer dependencies (since all dependencies are installed as peers),
but in npm, this is an important distinction. Prior to npm@7, peer
dependencies must be installed explicitly by consumers.DependencyType.BUNDLED: A runtime dependency that is bundled and shipped
with the module, so consumers are not required to install it.DependencyType.BUILD: The dependency is required to run the build task.DependencyType.TEST: The dependency is required to run the test task.DependencyType.DEVENV: The dependency is required for development (e.g. IDE plugins).If a dependency is added multiple times, the last specification will prevail. This allows you to override dependency specs added by projects or components.
For example, if you wish to change the version of the TypeScript compiler used in TypeScript projects:
const { typescript } = require('projen');
const project = new typescript.TypeScriptProject({
/* ... */
});
project.addDevDeps('typescript@^5');
project.synth();