ActivityPub Viewer

A small tool to view real-world ActivityPub objects as JSON! Enter a URL or username from Mastodon or a similar service below, and we'll send a request with the right Accept header to the server to view the underlying object.

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{ "@context": [ "https://www.w3.org/ns/activitystreams", { "ostatus": "http://ostatus.org#", "atomUri": "ostatus:atomUri", "inReplyToAtomUri": "ostatus:inReplyToAtomUri", "conversation": "ostatus:conversation", "sensitive": "as:sensitive", "toot": "http://joinmastodon.org/ns#", "votersCount": "toot:votersCount", "litepub": "http://litepub.social/ns#", "directMessage": "litepub:directMessage" } ], "id": "https://infosec.exchange/users/lcamtuf/statuses/109725682712687513/activity", "type": "Create", "actor": "https://infosec.exchange/users/lcamtuf", "published": "2023-01-21T06:04:07Z", "to": [ "https://www.w3.org/ns/activitystreams#Public" ], "cc": [ "https://infosec.exchange/users/lcamtuf/followers" ], "object": { "id": "https://infosec.exchange/users/lcamtuf/statuses/109725682712687513", "type": "Note", "summary": null, "inReplyTo": null, "published": "2023-01-21T06:04:07Z", "url": "https://infosec.exchange/@lcamtuf/109725682712687513", "attributedTo": "https://infosec.exchange/users/lcamtuf", "to": [ "https://www.w3.org/ns/activitystreams#Public" ], "cc": [ "https://infosec.exchange/users/lcamtuf/followers" ], "sensitive": false, "atomUri": "https://infosec.exchange/users/lcamtuf/statuses/109725682712687513", "inReplyToAtomUri": null, "conversation": "tag:infosec.exchange,2023-01-21:objectId=38926587:objectType=Conversation", "content": "<p>Time is a flat circle and all that.</p><p>It used to be that if you had a need for an embedded processor, you&#39;d either write code for a &quot;bare metal&quot; microcontroller, or grab a compact real-time OS of some sort (the latter mostly if you needed a complete networking stack, a filesystem, or something like that).</p><p>Nowadays, most people just get a powerful system-on-a-chip (SoC) running Linux, even if their project is as simple as blinking some Christmas lights. But Linux does Linux things, and getting predictable and performant hardware I/O from userspace is a crapshoot. You do &#39;echo 1 &gt;/sys/class/gpio/gpio60/value&#39; and some indeterminate time later, a pin changes state. Forget gigabit data transfer speeds - you might have a hard time playing back audio on a speaker.</p><p>So now, some SoCs come with a separate processor on the die - a Programmable Real-time Unit (PRU). It&#39;s a semi-standalone device that lets you run simple code in a &quot;bare metal&quot; environment with a bit of RAM and program memory to orchestrate your GPIO:</p><p><a href=\"https://beagleboard.org/pru\" target=\"_blank\" rel=\"nofollow noopener noreferrer\" translate=\"no\"><span class=\"invisible\">https://</span><span class=\"\">beagleboard.org/pru</span><span class=\"invisible\"></span></a></p><p>In this model, Linux running on the main CPU just tells the PRU &quot;please play back fart sounds on pin 60&quot;, and your code running on the PRU handles the particulars of toggling the pin in real time.</p><p>I suspect it&#39;s just a matter of time before we find a way to run Linux on the PRU, and then demand a second PRU to solve the I/O issues that would arise.</p>", "contentMap": { "en": "<p>Time is a flat circle and all that.</p><p>It used to be that if you had a need for an embedded processor, you&#39;d either write code for a &quot;bare metal&quot; microcontroller, or grab a compact real-time OS of some sort (the latter mostly if you needed a complete networking stack, a filesystem, or something like that).</p><p>Nowadays, most people just get a powerful system-on-a-chip (SoC) running Linux, even if their project is as simple as blinking some Christmas lights. But Linux does Linux things, and getting predictable and performant hardware I/O from userspace is a crapshoot. You do &#39;echo 1 &gt;/sys/class/gpio/gpio60/value&#39; and some indeterminate time later, a pin changes state. Forget gigabit data transfer speeds - you might have a hard time playing back audio on a speaker.</p><p>So now, some SoCs come with a separate processor on the die - a Programmable Real-time Unit (PRU). It&#39;s a semi-standalone device that lets you run simple code in a &quot;bare metal&quot; environment with a bit of RAM and program memory to orchestrate your GPIO:</p><p><a href=\"https://beagleboard.org/pru\" target=\"_blank\" rel=\"nofollow noopener noreferrer\" translate=\"no\"><span class=\"invisible\">https://</span><span class=\"\">beagleboard.org/pru</span><span class=\"invisible\"></span></a></p><p>In this model, Linux running on the main CPU just tells the PRU &quot;please play back fart sounds on pin 60&quot;, and your code running on the PRU handles the particulars of toggling the pin in real time.</p><p>I suspect it&#39;s just a matter of time before we find a way to run Linux on the PRU, and then demand a second PRU to solve the I/O issues that would arise.</p>" }, "updated": "2023-01-21T16:53:56Z", "attachment": [], "tag": [], "replies": { "id": "https://infosec.exchange/users/lcamtuf/statuses/109725682712687513/replies", "type": "Collection", "first": { "type": "CollectionPage", "next": "https://infosec.exchange/users/lcamtuf/statuses/109725682712687513/replies?only_other_accounts=true&page=true", "partOf": "https://infosec.exchange/users/lcamtuf/statuses/109725682712687513/replies", "items": [] } }, "likes": { "id": "https://infosec.exchange/users/lcamtuf/statuses/109725682712687513/likes", "type": "Collection", "totalItems": 124 }, "shares": { "id": "https://infosec.exchange/users/lcamtuf/statuses/109725682712687513/shares", "type": "Collection", "totalItems": 51 } } }