Run show commands

//native

/**

 * Run show commands

 * Run up to 10 show commands on a Cisco Nexus switch through NX-API and return the output of each, as structured JSON (cli_show) or as plain text (cli_show_ascii).

 */

export async function main(

  auth: RT.CiscoNxos,

  commands: string[],

  output_format: "json" | "text" | undefined

) {

  const cmds = (commands ?? []).map((c) => c.trim()).filter((c) => c !== "")

  if (cmds.length === 0) {

    throw new Error("Provide at least one show command")

  }

  // NX-API splits input on ';', and in text mode it runs any exec command:

  // keep this action to show commands.

  for (const c of cmds) {

    if (!/^show\s/i.test(c) || c.includes(";")) {

      throw new Error(`Not a single show command: ${c}`)

    }

  }

  // NX-API ignores show commands past the 10th in a single request

  if (cmds.length > 10) {

    throw new Error("NX-API accepts at most 10 show commands per request")

  }

  const type =

    (output_format || "json") === "text" ? "cli_show_ascii" : "cli_show"

  const outputs = await nxapi(auth, type, cmds)

  return outputs.map((o, i) => ({

    command: o.input ?? cmds[i],

    output: o.body,

  }))

}

type NxapiOutput = {

  input?: string

  body?: any

  code: string

  msg?: string

  clierror?: string

}

async function nxapi(

  auth: RT.CiscoNxos,

  type: "cli_show" | "cli_show_ascii" | "cli_conf",

  commands: string[]

): Promise<NxapiOutput[]> {

  const response = await fetch(new URL("/ins", auth.base_url), {

    method: "POST",

    headers: {

      Authorization: `Basic ${btoa(`${auth.username}:${auth.password}`)}`,

      "Content-Type": "application/json",

      Accept: "application/json",

    },

    // Keep "type" before "input": some NX-OS releases misparse the payload otherwise

    body: JSON.stringify({

      ins_api: {

        version: "1.0",

        type,

        chunk: "0",

        sid: null,

        input: commands.join(" ;"),

        output_format: "json",

      },

    }),

  })

  if (!response.ok) {

    throw new Error(`${response.status} ${await response.text()}`)

  }

  const text = await response.text()

  if (text.trimStart().startsWith("<")) {

    // NX-API falls back to XML when the output exceeds 1 MB

    throw new Error(

      `NX-API returned XML instead of JSON (outputs over 1 MB come back as XML): ${text.slice(0, 500)}`

    )

  }

  const data = JSON.parse(text)

  const raw = data?.ins_api?.outputs?.output

  const outputs: NxapiOutput[] =

    raw == null ? [] : Array.isArray(raw) ? raw : [raw]

  for (const o of outputs) {

    if (String(o.code) !== "200") {

      throw new Error(

        `${o.code} ${o.input ?? ""}: ${o.msg ?? ""} ${o.clierror ?? ""}`.trim()

      )

    }

  }

  return outputs

}