angular-cli/docs/documentation/stories/asset-configuration.md

Project assets

You use the assets array in .angular-cli.json to list files or folders you want to copy as-is when building your project.

By default, the src/assets/ folder and src/favicon.ico are copied over.

"assets": [
  "assets",
  "favicon.ico"
]

You can also further configure assets to be copied by using objects as configuration.

The array below does the same as the default one:

"assets": [
  { "glob": "**/*", "input": "./assets/", "output": "./assets/" },
  { "glob": "favicon.ico", "input": "./", "output": "./" },
]

glob is the a node-glob using input as base directory. input is relative to the project root (src/ default), while output is relative to outDir (dist default).

You can use this extended configuration to copy assets from outside your project. For instance, you can copy assets from a node package:

"assets": [
 { "glob": "**/*", "input": "../node_modules/some-package/images", "output": "./some-package/" },
]

The contents of node_modules/some-package/images/ will be available in dist/some-package/.

Writing assets outside of dist/

Because of the security implications, the CLI will always refuse to read or write files outside of the project itself (scoped by .angular-cli.json). It is however possible to write assets outside the dist/ build output folder during build.

Because writing files in your project isn't an expected effect of ng build, it is disabled by default on every assets. In order to allow this behaviour, you need to set allowOutsideOutDir to true on your asset definition, like so:

"assets": [
  {
    "glob": "**/*",
    "input": "./assets/",
    "output": "../not-dist/some/folder/",
    "allowOutsideOutDir": true
  },
]

This needs to be set for every assets you want to write outside of your build output directory.