CONTRIBUTING.md

Contribution Guidelines

If you are interested in contributing to the Substrate Documentation, please carefully read these contribution guidelines.

We lovingly stole these guidelines from Google's Fuchsia project, and modified them for our needs.

• PR Checklist

• Documentation Standards

• Documentation Types

• Documentation Comments

• Documentation Style

• Multilingual Translation

PR Checklist

• Are the audience and objective of the document clear? E.g. a document for developers that should teach them about transaction fees.
• Is the writing:
  • Clear: No jargon.
  • Precise: No ambiguous meanings.
  • Concise: Free of superfluous detail.
• Does it follow our style guide?
• If this is a new page, does the PR include the appropriate infrastructure, e.g. adding the page to a sidebar?
• Build the page ($ cd website && yarn start). Does it render properly? E.g. no funny lists or formatting.
• Do links go to rustdocs or devhub articles rather than code?
• If this PR addresses an issue in the queue, have you referenced it in the description?

Documentation Standards

A document about what to document and how to document it for people who create things that need documentation.

Why document?

Substrate is a new framework for building blockchains. Effective documentation allows new people to join and grow the project by having all necessary documentation be clear and concise.

Who is the audience?

The documentation described here is intended to address a technical audience, i.e. those who expect to implement or exercise APIs or understand the internal dynamics of the blockchain system. These standards are not intended for end-user product documentation.

What should I document?

Document protocols, introduce essential concepts, explain how everything fits together.

• Conventions: e.g. this document about documentation, code style

• System Design: e.g. network stack, consensus, runtime, assumptions

• APIs: e.g. JSON-RPC, runtime functions

• Protocols: e.g. schemas, encodings, configuration files

• Tools: e.g. subkey, build-spec, purge-chain

• Workflows: e.g. environment set up, test methodologies, where to find various parts, how to get work done

Where should I put documents?

Documentation that is only for developers working on creating or maintaining a specific part of the code should be kept in the same directory as the source code.

Substrate documentation is split into three projects:

• Substrate Recipes - substrate.dev/recipes/

  Examples and best practice guidelines on how to develop with Substrate, complete with working code. If you create an example of using a specific Substrate feature, it belongs in the recipes.

• Substrate Rust Documentation - substrate.dev/rustdocs/

  Auto-generated Rust documentation from the Substrate repository. See Documentation Comments.

• Substrate Developer Documentation - substrate.dev/docs/

  Instructions, conceptual overviews, and procedural documentation for developers who are working on Substrate. This directory includes documentation on how to get started, build, run, and test Substrate. You should organize the content that you create by specific activities, such as testing, getting started, or by workflow topic.

  Images that are used in the documentation belong in the common assets directory. Avoid placing images in the same directory as documentation.

What documentation should I create?

Most documentation can be divided into four categories:

• Reference - Information-oriented documentation

• Conceptual - Understanding-oriented documentation

• Procedural

  • How to - Goal-oriented documentation

  • Tutorial - Learning-oriented documentation

See Documentation Types for more information.

However, comments in your code are very important for maintainability and helping other people understand your code. See the Code Comment Guidelines for style guidelines related to comments for your code.

What documentation style guidelines should I follow?

It is important to follow documentation style guidelines to ensure that the documentation created by a large number of contributors can flow together. See Documentation Style Guide.

How can I link to other docs in my documentation?

Use absolute paths starting with / and ending with .md, like /knowledgebase/getting-started/index.md.

How can I link to source code in my documentation?

Use the /rustdocs to link to specific parts of the Substrate source code, for example a module's trait. When referencing specific lines of code, copy those lines into the documentation.

DO NOT link to specific lines of code -- substrate changes often and links that reference specific locations in the code become inaccurate fast and are not easily maintainable.

How can I expose my documentation?

Documentation is only useful when users can find it. Adding links to or from existing documentation greatly improves the chances that someone can find your documentation.

Tips for leaving breadcrumbs:

• Table of contents: Add links to documentation in the left side navigation on substrate.dev.

• Top-down linkage: Add links from more general documents to more specific documents to help readers learn more about specific topics. The conceptual section is a good starting point for top-down linkage.

• Bottom-up linkage: Add links from more specific documents to more general documents to help readers understand the full context of the topics being discussed. Adding links from module, class, or protocol documentation comments to conceptual documentation overviews can be particularly effective.

• Sideways linkage: Add links to documents on subjects that help readers better understand the content of your document.

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Documentation Types

Documentation is an important part of any product or feature because it lets users know how to properly use a feature that has been implemented. These guidelines are meant to be a quick and easy reference for types of documentation. For information on documentation style guidelines, see Documentation Style Guide.

Conceptual, procedural, or reference documentation

Most documentation can be divided into these categories:

• Reference - Documentation that provides a source of information about parts of a system such as API parameters.

• Conceptual - Documentation that helps you understand a concept such as the Substrate runtime.

• Procedural

  • How-to - Documentation that provides steps on how to accomplish a goal such as setting up your computer to compile Substrate.

  • Tutorial - Documentation that provides steps of a learning path (this tends to be a much bigger procedure than a how-to) such as create a Substrate runtime module.

You should write a reference document if you need to provide information about parts of a system including, but not limited to APIs and CLIs. Reference documentation should allow the user to understand how to use a specific feature quickly and easily.

You should write a conceptual document if you plan on explaining a concept about a product. Conceptual documents explain a specific concept, but for the most part they do not include actual examples. They provide essential facts, background, and diagrams to help your readers build a foundational understanding of a product or topic. You should not explain industry standards that your audience should be familiar with, for example, TCP/IP. You might explain how this concept ties in with your feature, but you should not explain the basics behind that industry-standard concept.

You should write a procedural document if you plan on explaining to a user how to use a specific feature and are able to guide a user through simple numbered steps. Procedural documents tend to reinforce the concepts that were explained in a conceptual document by giving one or more examples that might be useful for users.

Procedural documents are divided into two categories:

• How-to - Consider writing a how-to when you want to help the user accomplish a very specific goal.

• Tutorial - Consider writing a tutorial when you want to help the user learn about a bigger goal that might involve working with multiple parts of a product or feature. The tutorial should not go over 60 minutes and should provide the user with a specific result.

How can you decide what type of document is appropriate for your use case? Consider these examples:

• What is a car? This is a conceptual document.

• How does an internal combustion engine work? This is a conceptual document that would be geared towards more advanced users.

• How to use the alarm manager in Android. That is a procedural document. The main set of procedures can be a tutorial since a hand-held example is ideal to understand the function of the alarm manager.

• How to operate the radio. This is a procedural document. This can be a how to guide since the use of a radio tends to be quite intuitive and in most cases wouldn't require a hand-held example.

• How does a transistor work? This is a conceptual document that would be geared towards a more advanced user.

• Functions of the car radio. This is a reference document.

• How a new technology improved the car radio. This is a conceptual document.

Note: A feature may require more than one type of document. You may decide that your feature requires just reference documentation or that you need reference, conceptual, and how to documentation.

Reference documentation

Reference documentation should provide information about parts of a system including, but not limited to APIs and CLIs. The style of reference documentation should be the same for all reference documentation of that type. For example, API documentation should define all of the API's parameters, indicate if a parameter is required or optional, and show examples of the use of the API. These examples should be very generic and simple. If you feel like you need a more elaborate example, consider creating a procedural document to reinforce your reference documentation.

Conceptual documentation

Conceptual documentation should try to be brief and for the most part should not go above 1 page. If you need to write more than one page to describe a concept, consider breaking that concept into sub-concepts by using headings. By keeping your document brief you achieve the following:

• You do not overwhelm your reader with a wall of text.

• You avoid losing the reader while they read your document.

The first paragraph should try to be a brief summary of your document, this should allow the user to quickly read through it, determine what the document covers, and if this is relevant to what they want to learn. If your document has multiple headings, you should include a bulleted list with the high-level headings after this first paragraph. You should use graphics, images, or diagrams to reinforce certain concepts. The text that comes before and after the graphic should explain what the graphic shows. Images should be saved in a feature specific images/ directory or a common images/ directory. You should also save the source file of your images in an images/src/ directory.

Good conceptual documentation usually includes:

• Description rather than instruction

• Background concepts

• Diagrams or other visual aids (preferably in .png format)

• Links to how-to and/or reference docs After writing your document, it is good practice to proofread the document, put yourself in the user's shoes (no longer being the expert that developed the feature), and try to answer these questions:

  • Does the information in the document explain the concept completely?

  • Is there information that is not needed for this concept? If so, remove it.

  • Is there unnecessary detail about how things might work in the background?

  • If I am the user, is there additional information I would have liked to know?

Then, add your feedback into your document.

Procedural documentation

Procedural documents are divided into two categories:

• How-to - Consider writing a how-to when you want to help the user accomplish a very specific goal.

• Tutorial - Consider writing a tutorial when you want to help the user learn about a bigger goal that might involve working with multiple parts of a product or feature.

Procedural documentation should try to be brief and each task within your documentation should try to avoid going above 10 steps (tutorials can be much longer, but should not exceed 45-60 minutes for a user to complete). You should divide long procedures into multiple sub-tasks to try to keep tasks manageable for a user. For example, if you wanted to write a procedural document for taking care of a dog, you might have a table of content that looks like this:

How to take care of a dog:

• Feeding a dog

• Washing a dog

• Trimming a dog's nails

• Brushing a dog

• Playing with a dog

Difference between a tutorial and a how to

At a very high-level, a tutorial is essentially a large how-to, composed of various smaller how-tos. Tutorials are great when you want to give the user a hand-held experience of working through a task, especially if this task is considered a little more complicated and might involve working with various areas of a product. On the other hand, a how-to should describe the steps on how to work through a minor task that should only involve a single area of a product.

Consider the following when you think that you might need to create a tutorial:

• How many tutorials are planned for this general feature? Keep in mind that you do not want a whole documentation set to just be tutorials, use them in moderation.

• Would this procedural documentation benefit from having a very specific example through a tutorial?

• Do you want to expose an exciting feature from the product through the tutorial? This helps you highlight a neat feature that a user might not know about without doing a tutorial.

General procedural documentation guidelines

• Each task or subtask should have a paragraph that lets a user know what the task is about and what a user should be able to do after performing the steps.

• Use screenshots or graphics to assist a user in navigating a user interface (UI).

• A procedural document should not have to explain any concepts to a user, but should reference conceptual documents in case a user does not know about a certain concept. For example, a procedure with a reference to a conceptual document might look like this:

  Configure the server with the appropriate configuration. For more information about server configurations, see "server configuration".

• Avoid giving the user multiple paths to select from when working through procedures. When you avoid giving the user choices, your documentation should lead all users to the same end result (for example, starting the server).

• If a procedural document is meant for beginner users, avoid adding procedures that you might consider better suited for advanced users. If your document is intended for advanced users, state it up front and give them a list of prerequisites before they go through your how to or tutorial.

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Documentation Comments

Comments in your code are very important for maintainability and helping other people understand your code. Documentation comments are especially effective at describing the purpose of protocols, structures, methods, data types, and other elements of program code.

Documentation comments should be applied consistently to all public APIs since they are a valuable asset for consumers.

Tips for writing effective documentation comments:

• Write in plain U.S. English.

• Write complete sentences and paragraphs.

• Write clear and brief comments, no more than a few sentences.

• Follow the approved style guide for the Rust programming language.

• Avoid creating running words that are not compound words. For example "notready" is two words run together. Use an appropriate separator, for example "not ready", "notReady", "not_ready", or "not-ready").

• Always add value. Don't restate what is already indicated by the type signature.

• Describe units of measure and integrity constraints of variables.

• Link to conceptual documentation for more complete descriptions of how APIs fit together as a whole.

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Documentation Style

It is important to create documentation that follows similar guidelines. This allows documentation to be clear and concise while allowing users to easily find necessary information.

These are general style guidelines that can help create clearer documentation:

• Write in plain U.S. English. You should write in plain U.S. English and try to avoid over-complicated words when you describe something.

• Avoid using pronouns such as "I" or "we". These can be quite ambiguous when someone reads the documentation. It is better to say "You should do…." instead of "We recommend that you do….". It is OK to use "you" as this allows the documentation to speak to a user.

• If you plan on using acronyms, you should define them the first time you write about them. For example, looks good to me (LGTM). Don't assume that everyone will understand all acronyms. You do not need to define acronyms that might be considered industry standards such as TCP/IP.

• In most cases, avoid future tense. Words such as "will" are very ambiguous. For example "you will see" can lead to questions such as "when will I see this?". In 1 minute or in 20 minutes? In most cases, assume that when someone reads the documentation you are sitting next to them and reading the instructions to them.

• Use active voice. You should always try to write in the active voice since passive voice can make sentences very ambiguous and hard to understand. There are very few cases where you should use the passive voice for technical documentation.

  • Active voice - the subject performs the action denoted by the verb.

    • "The operating system runs a process." This sentence answers the question on what is happening and who/what is performing the action.

  • Passive voice - the subject is no longer active, but is, instead, being acted upon by the verb - or passive.

    • "A process is being run." This sentence is unclear about who or what is running the process. You might consider "a process is run by the operating system", but the object of the action is still made into the subject of the sentence, which indicates passive voice. Passive voice tends to be wordier than active voice, which can make your sentence unclear. In most cases, if you use "by" this indicates that your sentence might be still be in passive voice. A correct way of writing this example is, "The operating systems runs the process."

• Do not list future plans for a product/feature. "In the future, the product will have no bugs." This leads to the question as to when this would happen, but most importantly this is not something that anyone can guarantee will actually happen.

• Do not talk about how certain features work behind the covers unless it is absolutely necessary. Always ask yourself, "Is this text necessary to understand this concept or to get through these instructions?" This also leads to shorter (less maintenance) and more concise (happier readers) documentation.

• Avoid using uncommon words, highly technical words, or jargon that users might not understand. Also, avoid using idioms such as "that's the way the cookie crumbles", while it might make sense to you, it may not translate well into another language. Keep in mind that a lot of users are non-native English speakers.

• Use compound words correctly. Use the compound words that give the correct meaning. For example, "set up" (verb) and "setup" (noun) have different meanings.

• Avoid using words such as "best" or "great" since these are all relative terms. How can you prove that "this operating system is the best?"

• Avoid referencing proprietary information. This can refer to any potential terminology or product names that may be trademarked or any internal information (API keys, machine names, etc…).

• Avoid starting a sentence with "this" since it is unclear what "this" references.

  • For example: "The operating system is fast and efficient. This is what makes it well designed." Does "this" refer to fast, efficient, or operating system? Consider using: "The operating system is well designed because it is fast and efficient."

• Keep sentences fairly short and concrete. Using punctuation allows your reader to follow instructions or concepts. If by the time you read the last word of your sentence, you can't remember how the sentence started, it is probably too long. Also, short sentences are much easier to translate correctly.

• Know your audience. It is good practice to know your audience before you write documentation. Your audience can be, for example, developers, end-users, integrators, etc. and they can have varying degrees of expertise and knowledge about a specific topic. Knowing your audience allows you to understand what information your audience should be familiar with. When a document is meant for a more advanced audience, it is best practice to state it up front and let the user know prerequisites before reading your document.

• Use markdown. You must create documentation in markdown (.md) and keep the markdown file wrapped to a 120 character column size.

• Be respectful