Create change request

//native

function authHeader(auth: RT.Servicenow) {

  return auth.token

    ? `Bearer ${auth.token}`

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

}

// Change Management API fields come back as { value, display_value }.

function value(field: any) {

  return field != null && typeof field === "object" ? field.value : field

}

function label(field: any) {

  return field != null && typeof field === "object"

    ? field.display_value

    : field

}

/**

 * Create Change Request

 * Create a normal, emergency or standard change request through the Change Management API (/api/sn_chg_rest, documented in the Yokohama and Brazil API references; needs the itil, change_manager or admin role). A standard change takes the sys_id of a standard change template (std_change_record_producer), whose description and plans cannot be overridden. Reference fields (assignment_group, cmdb_ci) take sys_ids; dates use 'YYYY-MM-DD HH:MM:SS' in UTC. Returns sys_id, number, state and the full record; fields ServiceNow did not apply are listed in ignored_fields.

 */

export async function main(

  auth: RT.Servicenow,

  type: "normal" | "emergency" | "standard",

  short_description: string,

  standard_change_template_id: string | undefined,

  description: string | undefined,

  assignment_group: string | undefined,

  cmdb_ci: string | undefined,

  start_date: string | undefined,

  end_date: string | undefined,

  fields: { [key: string]: any } | undefined

) {

  let path: string

  if (type === "standard") {

    if (!standard_change_template_id) {

      throw new Error(

        "standard_change_template_id is required for a standard change"

      )

    }

    path = `change/standard/${encodeURIComponent(standard_change_template_id)}`

  } else if (type === "normal" || type === "emergency") {

    path = `change/${type}`

  } else {

    throw new Error(`Unknown change type: ${type}`)

  }

  // The create endpoints take the record fields as query parameters, not a JSON body.

  const url = new URL(`${auth.instance_url}/api/sn_chg_rest/${path}`)

  const values: { [key: string]: any } = {

    ...(fields ?? {}),

    short_description,

    description,

    assignment_group,

    cmdb_ci,

    start_date,

    end_date,

  }

  for (const [key, v] of Object.entries(values)) {

    if (v != null && v !== "") {

      url.searchParams.append(

        key,

        typeof v === "object" ? JSON.stringify(v) : String(v)

      )

    }

  }

  const response = await fetch(url, {

    method: "POST",

    headers: {

      Authorization: authHeader(auth),

      Accept: "application/json",

    },

  })

  if (!response.ok) {

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

  }

  const { result } = (await response.json()) as { result: any }

  return {

    sys_id: value(result.sys_id),

    number: value(result.number),

    state: value(result.state),

    state_label: label(result.state),

    ignored_fields: result.__meta?.ignoredFields ?? [],

    record: result,

  }

}