@meru2802/nexus-modscript-composer

Compose multi-layer deployment scripts for NexusEPM agents. Takes individual L0 monitoring/collection scripts and produces a composed L1 collection script + L2 deployment wrapper (systemd service on Linux, Scheduled Task on Windows).

Install

npm install @meru2802/nexus-modscript-composer

Usage

import { generateFinalScript } from "@meru2802/nexus-modscript-composer";

const l0Bodies = [tomcatScript, postgresqlScript]; // raw L0 script strings with metadata headers

const result = await generateFinalScript(l0Bodies, {
  platform: "windows",
  templateUrls: {
    l1: "https://nexus-endpoint-desktop-app.s3.ap-south-1.amazonaws.com/l1-l2-templates/l1-windows.ps1.tmpl",
    l2: "https://nexus-endpoint-desktop-app.s3.ap-south-1.amazonaws.com/l1-l2-templates/l2-windows.ps1.tmpl",
  },
  orgId: "acme-corp",
  icebergEndpoint: "https://iceberg.example.com/api/v1/collect",
  agentId: "agent-001",
  authToken: "bearer-token",
  bufferTime: "5m",
  timeout: "10m",
});

console.log(result.l1Script);  // composed L1 collection script
console.log(result.l2Script);  // L2 deployment wrapper
console.log(result.modules);   // ["tomcat", "postgresql"]

Template URLs

| Platform | Layer | URL | |----------|-------|-----| | Linux | L1 | https://nexus-endpoint-desktop-app.s3.ap-south-1.amazonaws.com/l1-l2-templates/l1-linux.sh.tmpl | | Linux | L2 | https://nexus-endpoint-desktop-app.s3.ap-south-1.amazonaws.com/l1-l2-templates/l2-linux.sh.tmpl | | Windows | L1 | https://nexus-endpoint-desktop-app.s3.ap-south-1.amazonaws.com/l1-l2-templates/l1-windows.ps1.tmpl | | Windows | L2 | https://nexus-endpoint-desktop-app.s3.ap-south-1.amazonaws.com/l1-l2-templates/l2-windows.ps1.tmpl |

generateFinalScript(l0ScriptBodies, options)

Parameters

l0ScriptBodies string[] -- Array of raw L0 script contents. Each string must include the full metadata header (# ==== NEXUS MODSCRIPT L0 ==== ... # ==== END METADATA ====) followed by the function body. All L0 scripts must target the same OS_FAMILY as the platform option.

options GenerateOptions:

| Field | Type | Required | Default | Description | |-------|------|----------|---------|-------------| | platform | "linux" \| "windows" | Yes | -- | Target OS. Must match the OS_FAMILY in all L0 scripts. | | templateUrls | { l1: string, l2: string } | Yes | -- | URLs to fetch the L1 and L2 template files. See table above. | | orgId | string | No | "test-client" | Organization ID baked into L1 for Iceberg payloads. | | icebergEndpoint | string | No | "https://iceberg.example.com/api/v1/collect" | URL where L1 POSTs collected data. Written to the L2 env file. | | agentId | string | No | "test-agent-001" | Agent identifier included in Iceberg payloads. | | authToken | string | No | "test-bearer-token" | Bearer token for Iceberg API authentication. | | bufferTime | string | No | "5m" | Wait time after L1 completes before next run. Accepts "30s", "5m", "1h". Linux: OnUnitInactiveSec. Windows: Start-Sleep in wrapper loop. | | timeout | string | No | "10m" | Max L1 execution time before force-kill. Same format as bufferTime. Linux: TimeoutStartSec. Windows: WaitForExit(). | | maxParallel | number | No | 5 | Max parallel L0 modules. Linux: background jobs. Windows: runspace pool size. | | previousServiceId | string | No | "" | Service ID of a previous deployment to tear down before installing the new one. | | writeToDisk | boolean | No | false | Write the composed scripts to timestamped files on disk. | | outputDir | string | No | "./final-scripts" | Directory for writeToDisk output. Resolved relative to process.cwd(). |

Return Value

{
  l1Script: string;    // Composed L1 collection script (all L0 modules merged)
  l2Script: string;    // L2 deployment wrapper (installs L1 as systemd service or Scheduled Task)
  platform: "linux" | "windows";
  modules: string[];   // Names of L0 modules included, e.g. ["tomcat", "postgresql"]
  l1Path?: string;     // File path if writeToDisk was true
  l2Path?: string;     // File path if writeToDisk was true
}

The function validates the composed scripts (structural checks, syntax via bash -n/shellcheck/pwsh, and a dry-run extraction test) before returning. It throws if validation fails.