Loklak Timeline Using Sphinx Extension In Yaydoc

In Yaydoc, I decided to add option, to show show the twitter timeline which showthe latest twitter feed. But I wanted to implement it using loklak instead of twitter embedded plugin. I started to search for an embedded plugin that exists for loklak. There is no such plugin, hence I built my own plugin. You can see the source code here.

Now that I have the plugin, the next phase is to add the plugin to the documentation. Adding the plugin by appending the plugin code to HTML is not viable. Therefore I decided to make Directive for Sphinx which adds a timeline based on the query parameter which user provides.

In order to make a Directive, I had to make a Sphinx extension which creates a timeline Directive. The Directive has to look like this

.. timeline :: fossasia

from docutils import nodes

from docutils.parsers import rst

class timeline(nodes.General, nodes.Element):

def visit(self, node):



def depart(self, node):

class TimelineDirective(rst.Directive):
  name = 'timeline'
  node_class = timeline
  has_content = True
  required_argument = 1
  optional_argument = 0
  final_argument_whitespace = False
  option_spec = {}

 def run(self):
    node = self.node_class()
    node.display_name = self.content[0]
    return [node]

def setup(app):            app.add_javascript("https://cdn.rawgit.com/fossasia/loklak-timeline-plugin/master/plugi
  app.add_node(timeline, html=(visit, depart))
  app.add_directive('timeline', TimelineDirective)

We have to create an empty class for Nodes that inherits`Node.General` and `Node.Elements`. This class is used for storing the value which will be passed by the directive.

I wrote a `Visit` function which executes when sphinx visits the `timeline` directive. `Visit` function basically appends the necessary html code needed to render the twitter timeline. Then I created TimelineDirective class which inherits rst.Directive. In that class, I defined a run method which read the argument from the directive and passed it to the node. Finally I defined a setup method which adds the loklak-timeline-plugin js to the render html node, and directive to the sphinx. Setup function has to be defined, in order to detect module as an extension by the sphinx.


Extending Markdown Support in Yaydoc

Yaydoc, our automatic documentation generator, builds static websites from a set of markup documents in markdown or reStructuredText format. Yaydoc uses the sphinx documentation generator internally hence reStructuredText support comes out of the box with it. To support markdown we use multiple techniques depending on the context. Most of the markdown support is provided by recommonmark, a docutils bridge for sphinx which basically converts markdown documents into proper docutil’s abstract syntax tree which is then converted to HTML by sphinx. While It works pretty well for most of the use cases, It does fall short in some instances. They are discussed in the following paragraphs.

The first problem was inclusion of other markdown files in the starting page. This was due to the fact that markdown does not supports any include mechanism. And if we used the reStructuredText include directive, the included text was parsed as reStructuredText. This problem was solved earlier using pandoc – an excellent tool to convert between various markup formats. What we did was that we created another directive mdinclude which converts the markdown to reStructuredText before inclusion. Although this was solved a while ago, The reason I’m discussing this here is that this was the inspiration behind the solution to our recent problem.

The problem we encountered was that recommonmark follows the Commonmark spec which is an ongoing effort towards standardization of markdown which has been somewhat lacking till now. The process is currently going on so the recommonmark library doesn’t yet support the concept of extensions to support various features of different markdown flavours not in the core commonmark spec. We could have settled for only supporting the markdown features in the core spec but tables not being present in the core spec was problematic. We had to support tables as it is widely used in most of the docs present in github repositories as GFM(Github Flavoured Markdown) renders ascii tables nicely.

The solution was to use a combination of recommonmark and pandoc. recommonmark provides a eval_rst code block which can be used to embed non-section reStructuredText within markdown. I created a new MarkdownParser class which inherited the CommonMarkParser class from recommonmark. Within it, using regular expressions, I convert any text within `<!– markdown+ –>` and `<!– endmarkdown+ –>`  into reStructuredText and enclose it within eval_rst code block. The result was that tables when enclosed within those trigger html comments would be converted to reST tables and then enclosed within eval_rst block which resulted in recommonmark renderering them properly. Below is a snippet which shows how this was implemented.

import re
from recommonmark.parser import CommonMarkParser
from md2rst import md2rst

MARKDOWN_PLUS_REGEX = re.compile('<!--\s+markdown\+\s+-->(.*?)<!--\s+endmarkdown\+\s+-->', re.DOTALL)
EVAL_RST_TEMPLATE = "```eval_rst\n{content}\n```"

def preprocess_markdown(inputstring):
    def callback(match_object):
        text = match_object.group(1)
        return EVAL_RST_TEMPLATE.format(content=md2rst(text))

    return re.sub(MARKDOWN_PLUS_REGEX, callback, inputstring)

class MarkdownParser(CommonMarkParser):
    def parse(self, inputstring, document):
        content = preprocess_markdown(inputstring)
        CommonMarkParser.parse(self, content, document)


Showing Pull Request Build logs in Yaydoc

In Yaydoc, I added the feature to show build status of the Pull Request. But there was no way for the user to see the reason for build failure, hence I decided to show the build log in the Pull Request similar to that of TRAVIS CI. For this, I had to save the build log into the database, then use GitHub status API to show the build log url in the Pull Request which redirects to Yaydoc website where we render the build log.

StatusLog.storeLog(name, repositoryName, metadata,  `temp/[email protected]/generate_${uniqueId}.txt`, function(error, data) {
                            if (error) {
                              status = "failure";
                            } else {
                              targetBranch = `https://${process.env.HOSTNAME}/prstatus/${data._id}`
                            github.createStatus(commitId, req.body.repository.full_name, status, description, targetBranch, repositoryData.accessToken, function(error, data) {
                              if (error) {
                              } else {

In the above snippet, I’m storing the build log which is generated from the build script to the mongodb and I’m appending the mongodb unqiueID to the `prstatus` url so that we can use that id to retrieve build log from the database.

exports.createStatus = function(commitId, name, state, description, targetURL, accessToken, callback) {
    url: `https://api.github.com/repos/${name}/statuses/${commitId}`,
    headers: {
      'User-Agent': 'Yaydoc',
      'Authorization': 'token ' + crypter.decrypt(accessToken)
    "content-type": "application/json",
    body: JSON.stringify({
      state: state,
      target_url: targetURL,
      description: description,
      context: "Yaydoc CI"
  }, function(error, response, body) {
    if (error!== null) {
      return callback({description: 'Unable to create status'}, null);
    callback(null, JSON.parse(body));

After saving the build log, I’m sending the request to GitHub for showing the status of the build along with build log url where user can click the detail link and can see the build log.


Showing Pull Request Build Status in Yaydoc

Yaydoc is integrated to various open source projects in FOSSASIA.  We have to make sure that the contributors PR should not break the build. So, I decided to check whether the PR is breaking the build or not. Then, I would notify the status of the build using GitHub status API.

exports.registerHook = function (data, accessToken) {
  return new Promise(function(resolve, reject) {
    var hookurl = 'http://' + process.env.HOSTNAME + '/ci/webhook';
    if (data.sub === true) {
      hookurl += `?sub=true`;
      url: `https://api.github.com/repos/${data.name}/hooks`,
      headers: {
        'User-Agent': 'Yaydoc',
        'Authorization': 'token ' + crypter.decrypt(accessToken)
      method: 'POST',
      json: {
        name: "web",
        active: true,
        events: [
        config: {
          url: hookurl,
          content_type: "json"
    }, function(error, response, body) {
      if (response.statusCode !== 201) {
        console.log(response.statusCode + ': ' + response.statusMessage);
        resolve({status: false, body:body});
      } else {
        resolve({status: true, body: body});

I’ll register the webhook, when user registers the repository to yaydoc for push and pull request event. Push event will be for building documentation and hosting the documentation to the GitHub pages. Pull_request event would be for checking the build of the pull request.

github.createStatus(commitId, req.body.repository.full_name, "pending", "Yaydoc is checking your build", repositoryData.accessToken, function(error, data) {
                    if (!error) {
                      var user = req.body.pull_request.head.label.split(":")[0];
                      var targetBranch = req.body.pull_request.head.label.split(":")[1];
                      var gitURL = `https://github.com/${user}/${req.body.repository.name}.git`;
                      var data = {
                        email: "[email protected]",
                        gitUrl: gitURL,
                        docTheme: "",
                        debug: true,
                        docPath: "",
                        buildStatus: true,
                        targetBranch: targetBranch
                      generator.executeScript({}, data, function(error, generatedData) {
                        var status, description;
                        if(error) {
                          status = "failure";
                          description = error.message;
                        } else {
                          status = "success";
                          description = generatedData.message;
                        github.createStatus(commitId, req.body.repository.full_name, status, description, repositoryData.accessToken, function(error, data) {
                          if (error) {
                          } else {

When anyone opens a new PR, GitHub will send  a request to yaydoc webhook. Then, I’ll send the status to GitHub saying that “Yaydoc is checking your build” with status `pending`. After, that I’ll documentation will be generated.Then, I’ll check the exit code. If the exit code is zero,  I’ll send the status `success` otherwise I’ll send `error` status.

Adding Github buttons to Generated Documentation with Yaydoc

Many times repository owners would want to link to their github source code, issue tracker etc. from the documentation. This would also help to direct some users to become a potential contributor to the repository. As a step towards this feature, we added the ability to add automatically generated GitHub buttons to the top of the docs with Yaydoc.

To do so we created a custom sphinx extension which makes use of http://buttons.github.io/ which is an excellent service to embed GitHub buttons to any website. The extension takes multiple config values and using them generates the `html` which it adds to the top of the internal docutils tree using a raw node.

    'watch': ('eye', 'https://github.com/{user}/{repo}/subscription'),
    'star': ('star', 'https://github.com/{user}/{repo}'),
    'fork': ('repo-forked', 'https://github.com/{user}/{repo}/fork'),
    'follow': ('', 'https://github.com/{user}'),
    'issues': ('issue-opened', 'https://github.com/{user}/{repo}/issues'),

def get_button_tag(user, repo, btn_type, show_count, size):
    spec = GITHUB_BUTTON_SPEC[btn_type]
    icon, href = spec[0], spec[1].format(user=user, repo=repo)
    tag_fmt = '<a class="github-button" href="{href}" data-size="{size}"'
    if icon:
        tag_fmt += ' data-icon="octicon-{icon}"'
    tag_fmt += ' data-show-count="{show_count}">{text}</a>'
    return tag_fmt.format(href=href,

The above snippet shows how it takes various parameters such as the user name, name of the repository, the button type which can be one of fork, issues, watch, follow and star, whether to display counts beside the buttons and whether a large button should be used. Another method named get_button_tags is used to read the various configs and call the above method with appropriate parameters to generate each button.

The extension makes use of the doctree-resolved event emitted by sphinx to hook into the internal doctree. The following snippet shows how it is done.

def on_doctree_resolved(app, doctree, docname):
    if not app.config.github_user_name or not app.config.github_repo:
    buttons = nodes.raw('', get_button_tags(app.config), format='html')
    doctree.insert(0, buttons)

Finally we add the custom javascript using the add_javascript method.


To use this with yaydoc, users would just need to add the following to their .yaydoc.yml file.

      watch: true
      star: true
      issues: true
      fork: true
      follow: true
    show_count: true
    large: true


  1.  Homepage of Github:buttons – http://buttons.github.io/
  2. Sphinx extension Tutorial – http://www.sphinx-doc.org/en/stable/extdev/tutorial.html

Using API Blueprint with Yaydoc

As part of extending the capability of Yaydoc to document APIs, this week we integrated API Blueprint with Yaydoc. Now we can parse apib files and add the parsed content to the generated documentation. From the official Homepage of API Blueprint,

API Blueprint is simple and accessible to everybody involved in the API lifecycle. Its syntax is concise yet expressive. With API Blueprint you can quickly design and prototype APIs to be created or document and test already deployed mission-critical APIs. It is a documentation-oriented web API description language. The API Blueprint is essentially a set of semantic assumptions laid on top of the Markdown syntax used to describe a web API.

To Integrate API Blueprint with Yaydoc, we used an sphinx extension named sphinxcontrib-apiblueprint. This extension can directly translate text in API Blueprint format into docutils nodes. The advantage with this approach as compared to using tools like aglio is that the generated html fits in nicely with the already existent theme. Though we may in future provide ability to generate html using tools like aglio if the user prefers. Adding an extension to sphinx is very easy. In the conf.py template, we added the extension to the already enabled list of extensions.

extensions += [‘sphinxcontrib.apiblueprint’]

The above extension provides a directive apiblueprint which can be then used to include apib files. The directive is very similar to the built in include directive. The difference is just that it should be only be used to include files in API Blueprint format. You can see an example below of how to use this directive.

.. apiblueprint:: <path to apib file>

Although this is enough for projects which use the ResT markup format, This cannot be used with projects using markdown as the primary markup format, since markdown doesn’t support the concept of directives. To solve this, we used the eval_rst block provided by recommonmark in Yaydoc. It allows users to embed valid ReST within markdown and recommonmark will properly parse the embedded text as ReST. Now a user can use this to use directives within markdown. You can see an example below.

.. apiblueprint:: <path to apib file>

In order to implement this, we used the AutoStructify class provided by recommonmark. Here’s a snippet from our conf.py template. Note that this does have far reaching effects. Now users would be able to use this to add constructs like toctree in markdown which wasn’t possible before.

from recommonmark.transform import AutoStructify

def setup(app):
    app.add_config_value('recommonmark_config', {
    'enable_eval_rst': True,
    }, True)

Let’s see all of this in action. Here’s a preview of a generated documentation with API Blueprint using Yaydoc.


Continuous Integration in Yaydoc using GitHub webhook API

In Yaydoc,  Travis is used for pushing the documentation for each and every commit. But this leads us to rely on a third party to push the documentation and also in long run it won’t allow us to implement new features, so we decided to do the continuous documentation pushing on our own. In order to build the documentation for each and every commit we have to know when the user is pushing code. This can be achieved by using GitHub webhook API. Basically we have to register our api to specific GitHub repository, and then GitHub will send a POST request to our API on each and every commit.

“auth/ci” handler is used to get access of the user. Here we request user to give access to Yaydoc such as accessing the public repositories , read organization details and write permission to write webhook to the repository and also I maintaining state by keeping the ci session as true so that I can know that this callback is for gh-pages deploy or ci deployOn

On callback I’m keeping the necessary informations like username, access_token, id and email in session. Then based on ci session state, I’m redirecting to the appropriate handler. In this case I’m redirecting to “ci/register”.After redirecting to the “ci/register”, I’m getting all the public repositories using GitHub API and then I’m asking the users to choose the repository on which users want to integrate Yaydoc CI

After redirecting to the “ci/register”, I’m getting all the public repositories using GitHub API and then I’m asking the users to choose the repository on which users want to integrate Yaydoc CI

router.post('/register', function (req, res, next) {
        url: `https://api.github.com/repos/${req.session.username}/${repositoryName}/hooks?access_token=${req.session.token}`,
        method: 'POST',
        json: {
          name: "web",
          active: true,
          events: [
          config: {
            url: process.env.HOSTNAME + '/ci/webhook',
            content_type: "json"
      }, function(error, response, body) {
          .then(function(result) {
            res.render("index", {
              showMessage: true,
              messages: `Thanks for registering with Yaydoc.Hereafter Documentation will be pushed to the GitHub pages on each commit.`

After user choose the repository, they will send a POST request to “ci/register” and then I’m registering the webhook to the repository and I’m saving the repository, user details in the database, so that it can be used when GitHub send request to push the documentation to the GitHub Pages.

router.post('/webhook', function(req, res, next) {
  var event = req.get('X-GitHub-Event')
  if (event == 'Push') {
          githubId: req.body.repository.owner.id,
          name: req.body.repository.name
      then(function(result) {
        var data = {
          email: result.email,
          gitUrl: req.body.repository.clone_url,
          docTheme: "",
        generator.executeScript({}, data, function(err, generatedData) {
            deploy.deployPages({}, {
              email: result.email,
              gitURL: req.body.repository.clone_url,
              username: result.username,
              uniqueId: generatedData.uniqueId,
              encryptedToken: result.accessToken
        status: true

After you register on webhook, GitHub will send a request to the url which we registered on the repository. In our case “https:/yaydoc.herokuapp.com/ci/auth” is the url. The type of the event can be known by reading ‘X-GitHub-Event’ header. Right now I’m registering only for the push event. So we’ll only be getting the push event. GitHub also gives us the repository details in the request body.

When the user makes a commit to the repository, GitHub will send a POST request to the Yaydoc’s server. Then, we’ll get the repository name and Github’s user ID from the request body. By use of this, I’ll retrieve the access token from the database which we already registered while the user registers the repository to the CI. The documentation will be generated using generate script and pushed to GitHub pages using deploy script.

Now Yaydoc generates documentation on every push when the user commits to the repository and also it will enable us to integrate new features in our own custom environment. We also plan to build a full featured CI platform.


Generating responsive email using mjml in Yaydoc

In Yaydoc, an email with a download, preview and deploy link will be sent to the user after documentation is generated. But then initially, Yaydoc was sending email in plain text without any styling, so I decided to make an attractive HTML email template for it. The problem with HTML email is adding custom CSS and making it responsive, because the emails will be seen on various devices like mobile, tablet and desktops. When going through the GitHub trending list, I came across mjml and was totally stunned by it’s capabilities. Mjml is a responsive email generation framework which is built using React (popular front-end framework maintained by Facebook)

Install mjml to your system using npm.

npm init -y && npm install mjml

Then add mjml to your path

export PATH="$PATH:./node_modules/.bin”

Mjml has a lot of react components pre-built for creating the responsive email. For example mj-text, mj-image, mj-section etc…

Here I’m sharing the snippet used for generating email in Yaydoc.

      <mj-all padding="0" />
      <mj-class name="preheader" color="#CB202D" font-size="11px" font-family="Ubuntu, Helvetica, Arial, sans-serif" padding="0" />
    <mj-style inline="inline">
      a { text-decoration: none; color: inherit; }
    <mj-container background-color="#ffffff">
      <mj-section background-color="#CB202D" padding="10px 0">
          <mj-text align="center" color="#ffffff" font-size="20px" font-family="Lato, Helvetica, Arial, sans-serif" padding="18px 0px">Hey! Your documentation generated successfully<i class="fa fa-address-book-o" aria-hidden="true"></i>
      <mj-section background-color="#ffffff" padding="20px 0">
          <mj-image src="http://res.cloudinary.com/template-gdg/image/upload/v1498552339/play_cuqe89.png" width="85px" padding="0 25px">
          <mj-text align="center" color="#EC652D" font-size="20px" font-family="Lato, Helvetica, Arial, sans-serif" vertical-align="top" padding="20px 25px">
            <strong><a>Preview it</a></strong>
            <br />
          <mj-image src="http://res.cloudinary.com/template-gdg/image/upload/v1498552331/download_ktlqee.png" width="100px" padding="0 25px" >
          <mj-text align="center" color="#EC652D" font-size="20px" font-family="Lato, Helvetica, Arial, sans-serif" vertical-align="top" padding="20px 25px">
            <strong><a>Download it</a></strong>
            <br />
          <mj-image src="http://res.cloudinary.com/template-gdg/image/upload/v1498552325/deploy_yy3oqw.png" width="100px" padding="0px 25px" >
          <mj-text align="center" color="#EC652D" font-size="20px" font-family="Lato, Helvetica, Arial, sans-serif" vertical-align="top" padding="20px 25px">
            <strong><a>Deploy it</a></strong>
            <br />
      <mj-section background-color="#333333" padding="10px">
        <mj-text align="center" color="#ffffff" font-size="20px" font-family="Lato, Helvetica, Arial, sans-serif" padding="18px 0px">Thanks for using Yaydoc<i class="fa fa-address-book-o" aria-hidden="true"></i>

The main goal of this example is to make a responsive email which looks like the image given below. So, In mj-head tag, I have imported all the necessary fonts using the mj-class tag and wrote my custom CSS in mj-style. Then I made a container with one row and one column using mj-container, mj-section and mj-column tag and changed the container background color to #CB202D using background-color attribute, then In that container I wrote a heading which says `Hey! Your documentation generated successfully`  with mj-text tag, Then you will get the red background top bar with the success message. Then moving on to the second part, I made a container with three columns and added one image to each column using mj-image tag by specifying image URL as src attribute, added the corresponding text below the mj-image tag using the mj-text tag. At last,  I  made one more container as the first one with different message saying `Thanks for using yaydoc`  with background color #333333

At last, transpile your mjml code to HTML by executing the following command.

mjml -r index.mjml -o index.html

Rendered Email

Testing child process using Mocha in Yaydoc

Mocha is a javascript testing framework. It can be used in both nodeJS and browser as well, also it is one of the most popular testing framework available out there. Mocha is widely used for the Behavior Driven Development (BDD). In yaydoc, we are using mocha to test our web UI. One of the main task in yaydoc is documentation generation. We build a bash script to do our documentation generation. We run the bash script using node’s child_process module, but then in order to run the test you have to execute the child process before test execution. This can be achieved by mochas’s before hook. Install mocha in to your system

npm install -g mocha

Here is the test case which i wrote in yaydoc test file.

const assert = require('assert')
const spawn = require('child_process').spawn
const uuidV4 = require("uuid/v4")
describe('WebUi Generator', () => {
  let uniqueId = uuidV4()
  let email = '[email protected].com'
  let args = [
    "-g", "https://github.com/fossasia/yaydoc.git",
    "-t", "alabaster",
    "-m", email,
    "-u", uniqueId,
    "-w", "true"
  let exitCode

  before((done) => {
    let process = spawn('./generate.sh', args)
    process.on('exit', (code) => {
      exitCode = code
  it('exit code should be zero', () => {
    assert.equal(exitCode, 0)

Describe() function is used to describe our test case. In our scenario we’re testing the generate script so we write as webui generator. As I mentioned above we have to run our child_process in before hook. It() function is the place where we write our test case. If the test case fails, an error will be thrown. We use the assert module from mocha to do the assertion. You can see our assertion in first it()  block for checking exit code is zero or not.

mocha test.js --timeout 1500000

Since documentation takes time so we have to mention time out while running mocha. If your test case passes successfully, you will get output similar to this.

WebUi Generator
    ✓ exit code should be zero



Documenting APIs with Yaydoc

API Documentation is a quick and concise way to tell a user about how to use a library or work with a program. It details classes, functions, parameters, return types and more. Courtesy of Sphinx, Yaydoc had build in support for Documenting APIs for Python based projects right from it’s inception. Sphinx has a built in tool autodoc which provides certain directives such as autoclass, automodule, etc which can be used to automatically extract docstrings from all specified Python packages and modules and use it to generate API documentation. As a user of Yaydoc you could add ReST sources files with appropriate directives provided by autodoc and we would handle the rest. As part of enhancing this feature we wanted to do three things.

  • Enhance support for Python
  • Extend API documentation to other languages apart from Python
  • Automate the process of generating ReST source files

For Enhancing support for python projects, we implemented a few things.

Since autodoc imports the modules it needs to document, There could be import errors if a dependency was not met. To fix this issue, Now a user can specify certain modules to be mocked. This would really come in handy with projects depending on packages with third party C extensions such as numpy, scipy, etc.

{% if mock_modules %}
mock_modules = [name.strip() for name in '{{ mock_modules }}'.split(',')]
sys.modules.update((mod_name, mock.Mock()) for mod_name in mock_modules)
{% endif %}

Apart from this, if we detect a setup.py in the repository or a requirements.txt, we automatically try to install from it to meet dependencies.

# autodoc imports the module while building source files. To avoid
# ImportError, install any packages in requirements.txt of the project
# if available
if [ -f $ROOT_DIR/setup.py ]; then
  pip install $ROOT_DIR/
elif [ -f $ROOT_DIR/requirements.txt ]; then
  pip install -q -r $ROOT_DIR/requirements.txt

We also crawl the repository to detect any packages and add them to sys.path. With these changes, a user can expected generated API docs without having to extend conf.py.

{% if autoapi_python == 'true' %}
for (dirpath, dirnames, filenames) in os.walk('{{ root_dir }}'):
    # Directory contains __init__.py. It should be a python package
    if '__init__.py' in filenames:
        # appending instead of inserting at front so that user
        # cannot overwrite some of our own modules.
{% endif %}

The second goal is a no brainer. We would like to support as many languages as we can. With this week’s update, Java has been added to the officially supported list of languages for which Yaydoc can generate full API documentation without any manual intervention. To extract API documentation for java source files, we used a sphinx extension named javasphinx. From the official javasphinx docs,

javasphinx is a Sphinx extension that provides a Sphinx domain for documenting Java projects and a javasphinx-apidoc command line tool for automatically generating API documentation from existing Java source code and Javadoc documentation.

javasphinx-apidoc -o source/ $ROOT_DIR/$AUTOAPI_JAVA_PATH/
sphinx-apidoc -o source/ $ROOT_DIR/$AUTOAPI_PYTHON_PATH/

For the third goal, we use the tools sphinx-apidoc and javasphinx-apidoc to generate source files.