Adds supersim pkg (#488)

* Adds supersim pkg

* Add README

* add node engine

* Add changeset for supersim

* Adds follow-redirects

This is for the case when github returns a 302 and we need to follow the value
provided in the location header to download the archive

.changeset/lazy-monkeys-grin.md

@@ -0,0 +1,5 @@
+---
+"supersim": patch
+---
+
+Initial publish

packages/supersim/.eslintrc.cjs

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+module.exports = {
+  extends: ['../../.eslintrc.js'],
+  ignorePatterns: ['.eslintrc.cjs']
+}
+

packages/supersim/.gitignore

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+bin

packages/supersim/README.md

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+# Supersim
+
+Supersim is a lightweight tool to simulate the Superchain locally (with a single L1 and multiple OP-Stack L2s).
+
+For more detailed documentation please refer to the [supersim repo](https://github.com/ethereum-optimism/supersim)
+
+# Installation
+
+**npm**
+```
+npx supersim
+```
+
+**pnpm**
+```
+pnpm dlx supersim
+```
+
+**yarn**
+```
+yarn dlx supersim
+```

packages/supersim/install.js

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+const fs = require('fs')
+const { https } = require('follow-redirects')
+const path = require('path')
+const os = require('os')
+const { exec } = require('child_process')
+
+const PLATFORM = os.platform()
+const ARCH = os.arch()
+const BIN_PATH = path.join(__dirname, 'bin')
+const SUPERSIM_VERSION = '0.1.0-alpha.13'
+
+const archiveFilename = {
+  darwin: {
+    arm64: 'supersim_Darwin_arm64.tar.gz',
+    x64: 'supersim_Darwin_x86_64.tar.gz',
+  },
+  linux: {
+    arm64: 'supersim_Linux_arm64.tar.gz',
+    x64: 'supersim_Linux_x86_64.tar.gz',
+  },
+  win32: {
+    arm64: 'supersim_Windows_arm64.zip',
+    x64: 'supersim_Windows_x86_64.zip',
+  },
+}
+
+function extractRelease(filename, outputPath) {
+  const cmd = filename.endsWith('.tar.gz')
+    ? `tar -xzf ${outputPath} -C ${BIN_PATH}`
+    : `unzip ${outputPath} -d ${BIN_PATH}`
+
+  exec(cmd, (err) => {
+    if (err) {
+      console.error('Error extracting', err)
+    } else {
+      console.log('Successfully extracted release')
+    }
+  })
+}
+
+async function main() {
+  const filename = archiveFilename[PLATFORM][ARCH]
+  if (!filename) {
+    console.error('Unsupported platform/architecture')
+    process.exit(1)
+  }
+
+  const downloadUrl = `https://github.com/ethereum-optimism/supersim/releases/download/${SUPERSIM_VERSION}/${filename}`
+  const outputPath = path.join(BIN_PATH, filename)
+
+  if (!fs.existsSync(BIN_PATH)) {
+    fs.mkdirSync(BIN_PATH)
+  }
+
+  console.log(`Attempting to fetch ${filename}`)
+
+  https
+    .get(downloadUrl, (res) => {
+      const fileStream = fs.createWriteStream(outputPath)
+      res.pipe(fileStream)
+
+      fileStream.on('finish', () => {
+        console.log(`Downloaded ${filename}`)
+        fileStream.on('close', () => extractRelease(filename, outputPath))
+      })
+    })
+    .on('error', (err) => {
+      console.error('Error downloading supersim', err)
+      process.exit(1)
+    })
+}
+
+;(async () => {
+  try {
+    await main()
+  } catch (err) {
+    console.error('Error setting up supersim', err)
+    process.exit(1)
+  }
+})()

packages/supersim/package.json

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+{
+    "name": "supersim",
+    "version": "0.0.1",
+    "description": "Supersim is a lightweight tool to simulate the Superchain locally",
+    "license": "MIT",
+    "author": "Optimism PBC",
+    "keywords": [
+        "optimism",
+        "ethereum",
+        "supersim",
+        "superchain"
+    ],
+    "engines": {
+        "node": ">=18.0.0"
+    },
+    "bin": {
+        "supersim": "./bin/supersim"
+    },
+    "scripts": {
+        "lint": "eslint install.js && pnpm prettier --check install.js",
+        "lint:fix": "eslint install.js --fix --quiet && pnpm prettier install.js --write --loglevel=warn",
+        "postinstall": "node install.js"
+    },
+    "dependencies": {
+        "follow-redirects": "^1.15.9"
+    }
+}