docs: traducir guide/schematics.md (angular-hispano#365)

Co-authored-by: Daniel Díaz <[email protected]>
Co-authored-by: Michael Prentice <[email protected]>

Author: 3 people

aio/content/guide/schematics.en.md

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+# Generating code using schematics
+
+A schematic is a template-based code generator that supports complex logic.
+It is a set of instructions for transforming a software project by generating or modifying code.
+Schematics are packaged into [collections](guide/glossary#collection) and installed with npm.
+
+The schematic collection can be a powerful tool for creating, modifying, and maintaining any software project, but is particularly useful for customizing Angular projects to suit the particular needs of your own organization.
+You might use schematics, for example, to generate commonly-used UI patterns or specific components, using predefined templates or layouts.
+You can use schematics to enforce architectural rules and conventions, making your projects consistent and inter-operative.
+
+## Schematics for the Angular CLI
+
+Schematics are part of the Angular ecosystem. The [Angular CLI](guide/glossary#cli)  uses schematics to apply transforms to a web-app project.
+You can modify these schematics, and define new ones to do things like update your code to fix breaking changes in a dependency, for example, or to add a new configuration option or framework to an existing project.
+
+Schematics that are included in the `@schematics/angular` collection are run by default by the commands `ng generate` and `ng add`.
+The package contains named schematics that configure the options that are available to the CLI for `ng generate` sub-commands, such as `ng generate component` and `ng generate service`.
+The subcommands for `ng generate` are shorthand for the corresponding schematic. You can specify a particular schematic (or collection of schematics) to generate, using the long form:
+
+<code-example language="bash">
+ng generate my-schematic-collection:my-schematic-name
+</code-example>
+
+or
+
+<code-example language="bash">
+ng generate my-schematic-name --collection collection-name
+</code-example>
+
+### Configuring CLI schematics
+
+A JSON schema associated with a schematic tells the Angular CLI what options are available to commands and subcommands, and determines the defaults.
+These defaults can be overridden by providing a different value for an option on the command line.
+See [Workspace Configuration](guide/workspace-config) for information about how you can change the generation option defaults for your workspace.
+
+The JSON schemas for the default schematics used by the CLI to generate projects and parts of projects are collected in the package [`@schematics/angular`](https://raw.githubusercontent.com/angular/angular-cli/v7.0.0/packages/schematics/angular/application/schema.json).
+The schema describes the options available to the CLI for each of the `ng generate` sub-commands, as shown in the `--help` output.
+
+## Developing schematics for libraries
+
+As a library developer, you can create your own collections of custom schematics to integrate your library with the Angular CLI.
+
+* An *add schematic* allows developers to install your library in an Angular workspace using `ng add`.
+
+* *Generation schematics* can tell the `ng generate` subcommands how to modify projects, add configurations and scripts, and scaffold artifacts that are defined in your library.
+
+* An *update schematic* can tell the `ng update` command how to update your library's dependencies and adjust for breaking changes when you release a new version.
+
+For more details of what these look like and how to create them, see:
+* [Authoring Schematics](guide/schematics-authoring)
+* [Schematics for Libraries](guide/schematics-for-libraries)
+
+### Add schematics
+
+An add schematic is typically supplied with a library, so that the library can be added to an existing project with `ng add`.
+The `add` command uses your package manager to download new dependencies, and invokes an installation script that is implemented as a schematic.
+
+For example, the [`@angular/material`](https://material.angular.io/guide/schematics) schematic tells the `add` command to install and set up Angular Material and theming, and register new starter components that can be created with `ng generate`.
+You can look at this one as an example and model for your own add schematic.
+
+Partner and third party libraries also support the Angular CLI with add schematics.
+For example, `@ng-bootstrap/schematics` adds [ng-bootstrap](https://ng-bootstrap.github.io/)  to an app, and  `@clr/angular` installs and sets up [Clarity from VMWare](https://vmware.github.io/clarity/documentation/v1.0/get-started).
+
+An add schematic can also update a project with configuration changes, add additional dependencies (such as polyfills), or scaffold package-specific initialization code.
+For example, the `@angular/pwa` schematic turns your application into a PWA by adding an app manifest and service worker, and the `@angular/elements`  schematic adds the `document-register-element.js` polyfill and dependencies for Angular Elements.
+
+### Generation schematics
+
+Generation schematics are instructions for the `ng generate` command.
+The documented sub-commands use the default Angular generation schematics, but you can specify a different schematic (in place of a sub-command) to generate an artifact defined in your library.
+
+Angular Material, for example, supplies generation schematics for the UI components that it defines.
+The following command uses one of these schematics to render an Angular Material `<mat-table>` that is pre-configured with a datasource for sorting and pagination.
+
+<code-example language="bash">
+ng generate @angular/material:table <component-name>
+</code-example>
+
+### Update schematics
+
+ The `ng update` command can be used to update your workspace's library dependencies. If you supply no options or use the help option, the command examines your workspace and suggests libraries to update.
+
+<code-example language="bash">
+ng update
+    We analyzed your package.json, there are some packages to update:
+
+      Name                               Version                  Command to update
+     --------------------------------------------------------------------------------
+      @angular/cdk                       7.2.2 -> 7.3.1           ng update @angular/cdk
+      @angular/cli                       7.2.3 -> 7.3.0           ng update @angular/cli
+      @angular/core                      7.2.2 -> 7.2.3           ng update @angular/core
+      @angular/material                  7.2.2 -> 7.3.1           ng update @angular/material
+      rxjs                               6.3.3 -> 6.4.0           ng update rxjs
+
+
+    There might be additional packages that are outdated.
+    Run "ng update --all" to try to update all at the same time.
+</code-example>
+
+If you pass the command a set of libraries to update (or the `--all` flag), it updates those libraries, their peer dependencies, and the peer dependencies that depend on them.
+
+<div class="alert is-helpful">
+
+If there are inconsistencies (for example, if peer dependencies cannot be matched by a simple [semver](https://semver.io/) range), the command generates an error and does not change anything in the workspace.
+
+We recommend that you do not force an update of all dependencies by default. Try updating specific dependencies first.
+
+For more about how the `ng update` command works, see [Update Command](https://github.com/angular/angular-cli/blob/master/docs/specifications/update.md).
+
+</div>
+
+If you create a new version of your library that introduces potential breaking changes, you can provide an *update schematic* to enable the `ng update` command to automatically resolve any such changes in the project being updated.
+
+For example, suppose you want to update the Angular Material library.
+
+<code-example language="bash">
+ng update @angular/material
+</code-example>
+
+This command updates both `@angular/material` and its dependency `@angular/cdk` in your workspace's `package.json`.
+If either package contains an update schematic that covers migration from the existing version to a new version, the command runs that schematic on your workspace.