basic scaffolding, some impl of addDocument

.gitignore

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+.idea
+node_modules

index.js

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+const ArweaveLib = require('arweave')
+const { LRUMap } = require('lru_map')
+
+const DEFAULT_OPTIONS = {
+  host: 'arweave.net',
+  port: 443,
+  protocol: 'https',
+  timeout: 20000,
+  logging: false,
+}
+
+// A single managed document
+class Document {
+  data
+  txID
+  client
+  synced
+
+  constructor(parentClient, content, version, name, meta) {
+    this.client = parentClient
+    this.data = {
+      content,
+      version,
+      name,
+      meta,
+    }
+    this.txID = undefined
+    this.synced = false
+  }
+
+  update(partialDocument) {
+    this.synced = false
+    this.data = {
+      ...this.data,
+      version: this.data.version + 1,
+      ...partialDocument,
+    }
+  }
+}
+
+// Constants
+const VERSION = "DOC_VERSION"
+const NAME = "DOC_NAME"
+
+// Thin wrapper client around Arweave for versioned document/data management.
+// Relies on an 'admin' wallet for fronting transaction + gas costs for users.
+class ArweaveClient {
+  #key
+  adminAddr
+  client
+  cache
+
+  // Construct a new client given the address of the admin account,
+  // keys to the wallet, and a set of options for connecting to an Arweave network.
+  // Options are identical to the ones supported by the official arweave-js library
+  constructor(adminAddress, key, cache_size = 500, options = DEFAULT_OPTIONS) {
+    this.#key = key
+    this.adminAddr = adminAddress
+    this.client = ArweaveLib.init(options)
+    this.cache = new LRUMap(500)
+  }
+
+  // Function to add a new document
+  async addDocument(content, version, name, meta) {
+    // create document + transaction
+    const doc = new Document(this, content, version, name, meta)
+    const tx = await this.client.createTransaction({
+      data: JSON.stringify(doc.data)
+    }, this.#key)
+
+    // tag with metadata (actual meta is stringified in body)
+    tx.addTag(VERSION, doc.data.version)
+    tx.addTag(NAME, doc.data.name)
+
+    // sign + send tx
+    await this.client.transactions.sign(tx, this.#key)
+    const txResult = await this.client.transactions.post(tx)
+
+    // success, update doc data, add to cache
+    doc.txID = tx.id
+    doc.synced = true
+    this.cache.set(doc.data.name, doc)
+
+    return {
+      ...txResult,
+      id: tx.id,
+    }
+  }
+
+  async updateDocument(content, version, meta) {
+  }
+
+  async getDocumentByName(name) {
+    // check if doc is in cache and entry is up to date
+    if (this.cache.has(name) && this.cache.get(name).synced) {
+      return this.cache.get(name)
+    }
+
+    // otherwise, fetch latest to cache
+
+    // return
+    return this.cache.get(name)
+  }
+
+  // get document by specific version and hash
+
+}