Lua Requires Chilkat v11.5.0+

Viewing a Simple Three-Step Execution Plan

See more CURL Examples

This example demonstrates a straightforward, valid dependency chain that results in a three-step execution plan. The goal is not to execute the requests, but to inspect how the plan is constructed using ExaminePlan.

The target curl command requires {{order_id}}. A helper function is defined to produce order_id, but it depends on customer_id. Another helper function produces customer_id, which depends on account_name.

Because account_name is provided as a known input, the dependency chain can be fully resolved:

• customer_id is obtained from account_name
• order_id is obtained from customer_id
• The target curl command uses order_id

When ExaminePlan is called, it builds and returns a three-step execution plan showing the order in which each function would be executed.

Lua

local chilkat = require("chilkat")

local httpCurl = chilkat.HttpCurl.new()

-- The target curl command requires {{order_id}}.
local targetCurl = "curl -X GET https://api.example.com/orders/{{order_id}}"

-- Define a helper function that produces order_id from customer_id.
local fnName = "getOrderId"
httpCurl:add_function(fnName, "curl -X GET https://api.example.com/order-id?customer={{customer_id}}")
httpCurl:add_output(fnName, "order.id", "order_id")

-- Define a helper function that produces customer_id from account_name.
fnName = "getCustomerId"
httpCurl:add_function(fnName, "curl -X GET https://api.example.com/customer-id?account={{account_name}}")
httpCurl:add_output(fnName, "customer.id", "customer_id")

-- Provide the starting known input.
httpCurl:set_var("account_name", "acme")

-- Examine the execution plan without running any requests.
local planJson = chilkat.JsonObject.new()
planJson.emit_compact = false

local success = httpCurl:examine_plan(targetCurl, planJson)

-- Success is expected to be true.
print("success = " .. tostring(success))

print(planJson:emit())

-- Expected result:
--
-- {
--   "plan": [{
--     "function": "getCustomerId",
--     "inputs": ["account_name"],
--     "outputs": ["customer_id"]
--   },{
--     "function": "getOrderId",
--     "inputs": ["customer_id"],
--     "outputs": ["order_id"]
--   },{
--     "function": "targetCurl",
--     "inputs": ["order_id"],
--     "outputs": []
--   }]
-- }