Getting Started

TechDocs functions as a plugin to Backstage, so you will need to use Backstage to use TechDocs.

If you haven't setup Backstage already, start here.

If you used npx @backstage/create-app, TechDocs may already be present.

You should skip to Setting the Configuration below.

Adding TechDocs frontend plugin

The first step is to add the TechDocs plugin to your Backstage application. Navigate to your new Backstage application directory. And then to your packages/app directory, and install the @backstage/plugin-techdocs package.

From your Backstage root directory

yarn --cwd packages/app add @backstage/plugin-techdocs

Once the package has been installed, you need to import the plugin in your app.

In packages/app/src/App.tsx, import TechDocsPage and add the following to FlatRoutes:

packages/app/src/App.tsx

import {
  DefaultTechDocsHome,
  TechDocsIndexPage,
  TechDocsReaderPage,
} from '@backstage/plugin-techdocs';

const AppRoutes = () => {
  <FlatRoutes>
    {/* ... other plugin routes */}
    <Route path="/docs" element={<TechDocsIndexPage />}>
      <DefaultTechDocsHome />
    </Route>
    <Route
      path="/docs/:namespace/:kind/:name/*"
      element={<TechDocsReaderPage />}
    />
  </FlatRoutes>;
};

It would be nice to decorate your pages with something else... Having a link that redirects you to a new issue page when you highlight text in your documentation would be really cool, right? Let's learn how to do this using the TechDocs Addon Framework!

With the TechDocs Addon framework, you can render React components in documentation pages and these Addons can be provided by any Backstage plugin. The framework is exported by the @backstage/plugin-techdocs-react package and there is a <ReportIssue /> Addon in the @backstage/plugin-techdocs-module-addons-contrib package for you to use once you have these two dependencies installed:

import {
  DefaultTechDocsHome,
  TechDocsIndexPage,
  TechDocsReaderPage,
} from '@backstage/plugin-techdocs';
import { TechDocsAddons } from '@backstage/plugin-techdocs-react';
import { ReportIssue } from '@backstage/plugin-techdocs-module-addons-contrib';

const AppRoutes = () => {
  <FlatRoutes>
    {/* ... other plugin routes */}
    <Route path="/docs" element={<TechDocsIndexPage />}>
      <DefaultTechDocsHome />
    </Route>
    <Route
      path="/docs/:namespace/:kind/:name/*"
      element={<TechDocsReaderPage />}
    >
      <TechDocsAddons>
        <ReportIssue />
      </TechDocsAddons>
    </Route>
  </FlatRoutes>;
};

I know, you're curious to see how it looks, aren't you? See the image below:

By clicking the open new issue button, you will be redirected to the new issue page according to the source code provider you are using:

That's it! Now, we need the TechDocs Backend plugin for the frontend to work.

Adding TechDocs Backend plugin

Navigate to packages/backend of your Backstage app, and install the @backstage/plugin-techdocs-backend package.

From your Backstage root directory

yarn --cwd packages/backend add @backstage/plugin-techdocs-backend

Create a file called techdocs.ts inside packages/backend/src/plugins/ and add the following

import { DockerContainerRunner } from '@backstage/backend-common';
import {
  createRouter,
  Generators,
  Preparers,
  Publisher,
} from '@backstage/plugin-techdocs-backend';
import Docker from 'dockerode';
import { Router } from 'express';
import { PluginEnvironment } from '../types';

export default async function createPlugin(
  env: PluginEnvironment,
): Promise<Router> {
  // Preparers are responsible for fetching source files for documentation.
  const preparers = await Preparers.fromConfig(env.config, {
    logger: env.logger,
    reader: env.reader,
  });

  // Docker client (conditionally) used by the generators, based on techdocs.generators config.
  const dockerClient = new Docker();
  const containerRunner = new DockerContainerRunner({ dockerClient });

  // Generators are used for generating documentation sites.
  const generators = await Generators.fromConfig(env.config, {
    logger: env.logger,
  });

  // Publisher is used for
  // 1. Publishing generated files to storage
  // 2. Fetching files from storage and passing them to TechDocs frontend.
  const publisher = await Publisher.fromConfig(env.config, {
    logger: env.logger,
    discovery: env.discovery,
  });

  // checks if the publisher is working and logs the result
  await publisher.getReadiness();

  return await createRouter({
    preparers,
    generators,
    publisher,
    logger: env.logger,
    config: env.config,
    discovery: env.discovery,
    cache: env.cache,
  });
}

You may need to install the dockerode package. But you may already have it in your backend since Scaffolder plugin also uses it.

See Concepts and TechDocs Architecture to learn more about how preparers, generators and publishers work.

The final step is to import the techdocs backend plugin in Backstage app backend. Add the following to your packages/backend/src/index.ts:

import techdocs from './plugins/techdocs';

// .... main should already be present.
async function main() {
  // ... other backend plugin envs
  const techdocsEnv = useHotMemoize(module, () => createEnv('techdocs'));

  // ... other backend plugin routes
  apiRouter.use('/techdocs', await techdocs(techdocsEnv));
}

That's it! TechDocs frontend and backend have now been added to your Backstage app. Now let us tweak some configurations to suit your needs.

New Backend System

To install TechDocs when using the New Backend system you will need to do the following.

Navigate to packages/backend of your Backstage app, and install the @backstage/plugin-techdocs-backend package.

From your Backstage root directory

yarn --cwd packages/backend add @backstage/plugin-techdocs-backend

Then in your backend index.ts you will add the following line.

packages/backend/src/index.ts

const backend = createBackend();

// Other plugins...

backend.add(import('@backstage/plugin-techdocs-backend'));

backend.start();

Note

The above is a very simplified example, you may have more content then this in your version.

Setting the configuration

See TechDocs Configuration Options for complete configuration reference.

Should TechDocs Backend generate docs?

techdocs:
  builder: 'local'

Note that we recommend generating docs on CI/CD instead. Read more in the "Basic" and "Recommended" sections of the TechDocs Architecture. But if you want to get started quickly set techdocs.builder to 'local' so that TechDocs Backend is responsible for generating documentation sites. If set to 'external', Backstage will assume that the sites are being generated on each entity's CI/CD pipeline, and are being stored in a storage somewhere.

When techdocs.builder is set to 'external', TechDocs becomes more or less a read-only experience where it serves static files from a storage containing all the generated documentation.

Choosing storage (publisher)

TechDocs needs to know where to store generated documentation sites and where to fetch the sites from. This is managed by a Publisher. Examples: Google Cloud Storage, Amazon S3, or local filesystem of Backstage server.

It is okay to use the local filesystem in a "basic" setup when you are trying out Backstage for the first time. At a later time, review Using Cloud Storage.

techdocs:
  builder: 'local'
  publisher:
    type: 'local'

Disabling Docker in Docker situation (Optional)

You can skip this if your techdocs.builder is set to 'external'.

The TechDocs Backend plugin runs a docker container with mkdocs installed to generate the frontend of the docs from source files (Markdown). If you are deploying Backstage using Docker, this will mean that your Backstage Docker container will try to run another Docker container for TechDocs Backend.

To avoid this problem, we have a configuration available. You can set a value in your app-config.yaml that tells the techdocs generator if it should run the local mkdocs or run it from docker. This defaults to running as docker if no config is provided.

techdocs:
  builder: 'local'
  publisher:
    type: 'local'
  generator:
    runIn: local

Setting generator.runIn to local means you will have to make sure your environment is compatible with techdocs.

You will have to install the mkdocs and mkdocs-techdocs-core package from pip, optionally also graphviz and plantuml from your OS package manager (e.g. apt).

You can do so by including the following lines right above USER node of your Dockerfile:

RUN apt-get update && \
    apt-get install -y python3 python3-pip python3-venv && \
    rm -rf /var/lib/apt/lists/*

ENV VIRTUAL_ENV=/opt/venv
RUN python3 -m venv $VIRTUAL_ENV
ENV PATH="$VIRTUAL_ENV/bin:$PATH"

RUN pip3 install mkdocs-techdocs-core

Please be aware that the version requirement could change, you need to check our Dockerfile and make sure to match with it.

On a Debian-based Docker container, Python packages must be either installed using the OS package manager or within a virtual environment (see the related PEP). Alternative is to use e.g. pipx for installing Python packages in an isolated environment.

The above Dockerfile snippet installs the latest mkdocs-techdoc-core package. Version numbers can be found in the corresponding changelog. In case you want to pin the version, use the example below:

RUN pip3 install mkdocs-techdocs-core==1.2.3

Note: We recommend Python version 3.11 or higher.

Caveat: Please install the mkdocs-techdocs-core package after all other Python packages. The order is important to make sure we get correct version of some of the dependencies.

Additional reading

• Creating and publishing your docs
• Back to README