feat(techdocs-cli): add --defaultPlugin argument to the generate command

Signed-off-by: Dominik Schwank <dominik.schwank@sda.se>

.changeset/twelve-elephants-pay.md

@@ -1,18 +1,7 @@
 ---
 '@backstage/plugin-techdocs-backend': minor
 '@backstage/plugin-techdocs-node': minor
+'@techdocs/cli': minor
 ---
 
-Add support for default mkdocs plugins.
-
-So far only `techdocs-core` was added as default to the list of mkdocs plugins. In case you use a
-custom image for techdocs, you also might want to add custom default plugins for mkdocs.
-With this change one can do that - example:
-
-```yaml
-techdocs:
-  generator:
-    mkdocs:
-      defaultPlugins:
-        - section-index
-```
+Add optional config and cli option for techdocs to specify default mkdocs plugins.

docs/features/techdocs/cli.md

@@ -141,6 +141,7 @@ Options:
                                   if not found.
   --etag <ETAG>                   A unique identifier for the prepared tree e.g. commit SHA. If provided it will be stored
                                   in techdocs_metadata.json.
+  --defaultPlugin <PLUGIN_NAME>   Plugins which should be added automatically to the mkdocs.yaml file. (default: [])
   --omitTechdocsCoreMkdocsPlugin  An option to disable automatic addition of techdocs-core plugin to the mkdocs.yaml files.
                                   Defaults to false, which means that the techdocs-core plugin is always added to the mkdocs file.
   --legacyCopyReadmeMdToIndexMd   Attempt to ensure an index.md exists falling back to using <docs-dir>/README.md or README.md

packages/techdocs-cli/cli-report.md

@@ -37,6 +37,7 @@ Options:
   -v --verbose
   --omitTechdocsCoreMkdocsPlugin
   --legacyCopyReadmeMdToIndexMd
+  --defaultPlugin [defaultPlugins...]
   -h, --help
 ```
 

packages/techdocs-cli/src/commands/generate/generate.ts

@@ -47,6 +47,7 @@ export default async function generate(opts: OptionValues) {
   const dockerImage = opts.dockerImage;
   const pullImage = opts.pull;
   const legacyCopyReadmeMdToIndexMd = opts.legacyCopyReadmeMdToIndexMd;
+  const defaultPlugins = opts.defaultPlugin;
 
   logger.info(`Using source dir ${sourceDir}`);
   logger.info(`Will output generated files in ${outputDir}`);
@@ -68,6 +69,7 @@ export default async function generate(opts: OptionValues) {
         mkdocs: {
           legacyCopyReadmeMdToIndexMd,
           omitTechdocsCorePlugin,
+          defaultPlugins,
         },
       },
     },

packages/techdocs-cli/src/commands/index.ts

@@ -70,6 +70,11 @@ export function registerCommands(program: Command) {
       'Attempt to ensure an index.md exists falling back to using <docs-dir>/README.md or README.md in case a default <docs-dir>/index.md is not provided.',
       false,
     )
+    .option(
+      '--defaultPlugin [defaultPlugins...]',
+      'Plugins which should be added automatically to the mkdocs.yaml file',
+      [],
+    )
     .alias('build')
     .action(lazy(() => import('./generate/generate').then(m => m.default)));