feat(lua-examples): add hello world process example

lua-examples/hello-world/package.json

@@ -0,0 +1,10 @@
+{
+  "name": "hello-world-process",
+  "version": "1.0.0",
+  "license": "MIT",
+  "type": "module",
+  "main": "index.js",
+  "dependencies": {
+    "@permaweb/ao-loader": "^0.0.9"
+  }
+}

lua-examples/hello-world/process.lua

@@ -0,0 +1,65 @@
+-- Corresponding local wasm at ./process.wasm
+local JSON = require("json")
+
+local process = { _version = "0.0.6" }
+
+local function assoc(prop, val, obj)
+  local result = {}
+  for p, k in pairs(obj) do
+    result[p] = k
+  end
+  result[prop] = val
+  return result
+end
+
+local function findObject(array, key, value)
+  for i, object in ipairs(array) do
+    if object[key] == value then
+      return object
+    end
+  end
+  return nil
+end
+
+local function dump(o)
+  if type(o) == 'table' then
+     local s = '{ '
+     for k,v in pairs(o) do
+        if type(k) ~= 'number' then k = '"'..k..'"' end
+        s = s .. '['..k..'] = ' .. dump(v) .. ','
+     end
+     return s .. '} '
+  else
+     return tostring(o)
+  end
+end
+
+local actions = {}
+actions['hello'] = function (state)
+  local _state = assoc('heardHello', true, state)
+  _state = assoc('helloCount', _state.helloCount + 1, _state)
+  return { state = _state, output = nil }
+end
+actions['world'] = function (state)
+  local _state = assoc('heardWorld', true, state)
+  return { state = _state, output = nil }
+end
+actions['raw'] = function (state)
+  return { state = state , output = JSON.encode(state) }
+end
+
+function process.handle(message, AoGlobal)
+  if state == nil then state = { helloCount = 0 } end
+
+  local func = findObject(message.tags, "name", "function")
+  if func == nil then return error({ code = 500, message = 'no function tag in the message'}) end
+
+  local res = actions[func.value](state, message, AoGlobal)
+  state = res.state
+  local output = res.output
+  if (state.heardHello and state.heardWorld) then state = assoc('happy', true, state) end
+
+  return { output = output }
+end
+
+return process

lua-examples/hello-world/repl.js

@@ -0,0 +1,56 @@
+import readline from 'node:readline'
+import fs from 'node:fs'
+
+import AoLoader from '@permaweb/ao-loader'
+
+const wasm = fs.readFileSync('./process.wasm')
+
+const rl = readline.createInterface({
+  input: process.stdin,
+  output: process.stdout
+})
+
+const env = {
+  process: {
+    id: 'PROCESS_TEST',
+    owner: 'OWNER'
+  }
+}
+
+async function repl (state) {
+  const handle = await AoLoader(wasm)
+
+  rl.question('hello world' + '> ', async function (line) {
+    // Exit the REPL if the user types "exit"
+    if (line === 'exit') {
+      console.log('Exiting...')
+      rl.close()
+      return
+    }
+    // Evaluate the JavaScript code and print the result
+    try {
+      const message = createMessage(line)
+      const { buffer, output } = handle(state, message, env)
+      if (output) console.log(JSON.parse(output))
+      // Continue the REPL
+      await repl(buffer)
+    } catch (err) {
+      console.log('Error:', err)
+      process.exit(0)
+    }
+  })
+}
+
+repl(null)
+
+function createMessage (expr) {
+  return {
+    owner: 'OWNER',
+    target: 'PROCESS',
+    tags: [
+      { name: 'Data-Protocol', value: 'ao' },
+      { name: 'ao-type', value: 'message' },
+      { name: 'function', value: expr }
+    ]
+  }
+}