Dapp-a-day 4: Access Control via `auth` by nikolai

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ethereum · @nikolai · Aug 11 '16

$37.83

Dapp-a-day 4: Access Control via `auth`

![Nexus Logo](https://i.imgur.com/JoJ8cXZ.png)

**Each weekday leading up to devcon2, Nexus will highlight a dapp, library, or package (something with a `dappfile`) as a promotion of our toolchain and as case studies for other developers. [Yesterday's Post.](https://steemit.com/ethereum/@nikolai/dapp-a-day-3-eth-token-wrapper)**

`ds-auth` is an opinionated access control pattern. It is an extension of the "owner" pattern which allow switching the contract into "ACL lookup" mode.

https://github.com/nexusdev/ds-auth

The dual control modes allow making sequences of administrative changes on-chain easier to write in the form of "update" contracts.

There may be some more usability/safety upgrades (like using distinct addresses and doing additional sanity checks when switching modes during handoffs), but it will likely be a major version upgrade.

You might notice that `DSBasicAuthority is DSAuth`. It's turtles all the way down! The control hierarchy should be "rooted" in something other than one of the given Authority types.

Tomorrow we will introduce one example: A fixed multisig actor.

👍 summon, riverhead, cass, eeks, nabilov, kennyrowe, bue, anonymous, nikolai, flandude, zebbra2014, aaseb, bue-witness, boy, walkerlv, murh, mini, nexusdev, littlekitty, daniel.pan, bunny, healthcare, dbrock, helen.tan, soupernerd, moon, weenis, genzai, stevenh512, mightypenguin

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@flandude · Aug 12 '16

A dapp a day keeps centralization at bay.

👍 scivanpoon

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@linkback-bot-v0 · Sep 10 '16

<div>  <p>  This post has been linked to from another place on Steem.  </p>  <ul>        <li>      <a href="https://steemit.com/ethereum/@nexusdev/dapp-a-day-18-erc20-token-vault"> Dapp-a-day 18: ERC20 token vault </a>      by      <a href="https://steemit.com/@nexusdev">  @nexusdev </a>     </li>        <li>      <a href="https://steemit.com/ethereum/@nexusdev/dapp-a-day-16-ds-burner"> Dapp-a-day 16: DS-burner </a>      by      <a href="https://steemit.com/@nexusdev">  @nexusdev </a>     </li>        <li>      <a href="https://steemit.com/ethereum/@dbrock/dapp-a-day-16"> Dapp-a-day 16 </a>      by      <a href="https://steemit.com/@dbrock">  @dbrock </a>     </li>        <li>      <a href="https://steemit.com/ethereum/@nexusdev/dapp-a-day-13-solidity-quirks"> Dapp-a-day 13: Solidity Quirks </a>      by      <a href="https://steemit.com/@nexusdev">  @nexusdev </a>     </li>        <li>      <a href="https://steemit.com/ethereum/@nexusdev/dapp-a-day-12-ds-base"> Dapp-a-day 12: DSBase – a reasonable base class </a>      by      <a href="https://steemit.com/@nexusdev">  @nexusdev </a>     </li>        <li>      <a href="https://steemit.com/ethereum/@nexusdev/dapp-a-day-11-whitelist-boring"> Dapp-a-day 11: Whitelist (Boring!) </a>      by      <a href="https://steemit.com/@nexusdev">  @nexusdev </a>     </li>      </ul>  <p> Learn more about  <a href="https://steemit.com/steem/@ontofractal/steem-linkback-bot-v0-3-released">    linkback bot v0.3</a>   </p>   <p>Upvote if you want the bot to continue posting linkbacks for your posts. Flag if otherwise.   Built by @ontofractal</p></div>

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