description: Single-page application with Blockstack
title: Building a Todo app
description: In this tutorial, you will learn about Blockstack authentication and storage by installing, running and reviewing the code for a "Todos" web app built with Blockstack and React.
@ -16,7 +16,7 @@ Markdown files. In addition to being able to write JSX in Markdown, it allows th
Markdown content with React components! This means that we are able to do some pretty complex things while a
contributor only has to know how to write Markdown.
-> Don't know what Markdown is? Here is a [helpful guide](https://guides.github.com/features/mastering-markdown/) for getting started with Markdown.
-> **Don't know what Markdown is?** Here is a [helpful guide](https://guides.github.com/features/mastering-markdown/) for learning it.
## Getting started
@ -103,7 +103,7 @@ description: A short, concise sentence describing what is on this page
Frontmatter gives us the ability to define some things within a page that the site can use, such as a page title or page description.
When adding any new page, please include a `title` and `description`.
-> **Did you know?** The term _Frontmatter_ comes from the section in a book at the beginning the details things like: Publisher’s name and address, Copyright information, Table of Contents, etc.
-> **Did you know?** The term _Frontmatter_ comes from the section in a book at the beginning detailing things like: publisher’s name and address, copyright information, table of contents, etc.
description: This document describes the Atlas network, a peer-to-peer content-addressed storage system whose chunks' hashes are announced on a public blockchain.
---
# Overview of the Atlas network
@ -10,11 +11,10 @@ allows users and developers to **permanently store** chunks of data that are
**replicated across every peer.** As long as at least one Atlas peer is online,
all chunks are available to clients.
This document is aimed at developers and technical users. The following
concepts are discussed:
This document is aimed at developers and technical users.
The reader of this document is expected to be familiar with the [Blockstack Naming Service](/core/naming/introduction)(BNS), as well as Blockstack's
storage system [Gaia](https://github.com/blockstack/gaia). We advise the reader
The reader of this document is expected to be familiar with the [Blockstack Naming Service](/core/naming/introduction)(BNS),
as well as Blockstack's storage system [Gaia](https://github.com/blockstack/gaia). We advise the reader
to familiarize themselves with both systems before approaching this document.
## Architecture
@ -112,11 +112,11 @@ feature table describes Atlas in relation to other popular chunk stores.
description: Learn how to create a namespace in the Blockstack Naming Service.
---
# Creating a Namespace
Making a namespace is very expensive. Given the large amount of cryptocurrency at stake in name creation, developers wanting to create their own namespaces should read [Understand Namespaces](/core/naming/namespaces) first. You should also read this document thoroughly before creating a namespace.
Making a namespace is very expensive. Given the large amount of cryptocurrency at stake in name creation, developers
wanting to create their own namespaces should read [Understand Namespaces](/core/naming/namespaces) first. You should
also read this document thoroughly before creating a namespace.
## Creation process
@ -12,7 +15,9 @@ There are four steps to creating a namespace.
### Step 1. Send a `NAMESPACE_PREORDER` transaction
This step registers the _salted hash_ of the namespace with BNS nodes, and burns the requisite amount of cryptocurrency. Additionally, this step proves to the BNS nodes that user has honored the BNS consensus rules by including a recent _consensus hash_ in the transaction (see the section on [BNS forks](#bns-forks) for details).
This step registers the _salted hash_ of the namespace with BNS nodes, and burns the requisite amount of cryptocurrency.
Additionally, this step proves to the BNS nodes that user has honored the BNS consensus rules by including a recent
_consensus hash_ in the transaction (see the section on [BNS forks](#bns-forks) for details).
### Step 2. Send a `NAMESPACE_REVEAL` transaction
@ -21,7 +26,10 @@ This second step reveals the salt and the namespace ID (pairing it with its
they expire or must be renewed, and it sets a _price function_ for the namespace
that determines how cheap or expensive names its will be.
The price function takes a name in this namespace as input, and outputs the amount of cryptocurrency the name will cost. The function does this by examining how long the name is, and whether or not it has any vowels or non-alphabet characters. The namespace creator has the option to collect name registration fees for the first year of the namespace's existence by setting a _namespace creator address_.
The price function takes a name in this namespace as input, and outputs the amount of cryptocurrency the name will cost.
The function does this by examining how long the name is, and whether or not it has any vowels or non-alphabet characters.
The namespace creator has the option to collect name registration fees for the first year of the namespace's existence by
setting a _namespace creator address_.
### Step 3. Seed the namespace with `NAME_IMPORT` transactions
@ -38,11 +46,18 @@ revealed in step 2.
## Consensus rules and competition for namespaces
Namespaces are created on a first-come first-serve basis. The BNS consensus rules require a `NAMESPACE_REVEAL` to be paired with a previous `NAMESPACE_PREORDER` sent within the past 24 hours. If two people try to create the same namespace, the one that successfully confirms both the `NAMESPACE_PREORDER` and `NAMESPACE_REVEAL` wins. The fee burned in the `NAMESPACE_PREORDER` is spent either way.
Namespaces are created on a first-come first-serve basis. The BNS consensus rules require a `NAMESPACE_REVEAL` to be
paired with a previous `NAMESPACE_PREORDER` sent within the past 24 hours. If two people try to create the same namespace,
the one that successfully confirms both the `NAMESPACE_PREORDER` and `NAMESPACE_REVEAL` wins. The fee burned in the
`NAMESPACE_PREORDER` is spent either way.
Once a user issues the `NAMESPACE_PREORDER` and `NAMESPACE_REVEAL`, they have 1 year before they must send the `NAMESPACE_READY` transaction. If they do not do this, then the namespace they created disappears (along with all the names they imported).
Once a user issues the `NAMESPACE_PREORDER` and `NAMESPACE_REVEAL`, they have 1 year before they must send the `NAMESPACE_READY`
transaction. If they do not do this, then the namespace they created disappears (along with all the names they imported).
Pairing the `NAMESPACE_PREORDER` and `NAMESPACE_REVEAL` steps is designed to prevent frontrunning. Frontrunning is a practice where name registrar uses insider information to register domains for the purpose of re-selling them or earning revenue from them. By registering the domains, the registrar locks out other potential registrars. Thus, through this pairing, a malicious actor cannot watch the blockchain network and race a victim to claim a namespace.
Pairing the `NAMESPACE_PREORDER` and `NAMESPACE_REVEAL` steps is designed to prevent frontrunning. Frontrunning is a
practice where name registrar uses insider information to register domains for the purpose of re-selling them or earning
revenue from them. By registering the domains, the registrar locks out other potential registrars. Thus, through this
pairing, a malicious actor cannot watch the blockchain network and race a victim to claim a namespace.
## Explore the namespace creation history
@ -57,7 +72,7 @@ If you would like to navigate a namespace history, you can. To do this, do the f
For example, the `https://core.blockstack.org/v1/namespaces/id` query returns this transaction history:
```json
{
{
"address": "1KdDvp1DJ4EYUZc8savutRN4vv1ZwvGfQf",
"base": 4,
"block_number": 373601,
@ -81,8 +96,8 @@ If you would like to navigate a namespace history, you can. To do this, do the f
description: This section explains registering BNS names and provides instructions for methods you can use to understand the cost of namespace registration.
---
# Register a name
This section explains registering BNS names and provides instructions for methods
you can use to understandt the cost of namespace registration.
you can use to understand the cost of namespace registration.
## Understand registration
@ -67,7 +68,7 @@ ignored.
## Getting a Name's Registration Fee
See [reference](https://core.blockstack.org/#price-checks-get-name-price).
-> See [reference](https://core.blockstack.org/#price-checks-get-name-price).
Thomas Osmonson
4 years ago