Parameter Resolver API

The parameter resolver expands ${...} placeholders inside any nested string / list / dict structure. It is invoked automatically on every task before the user template touches it, so values flow seamlessly between actions.

Resolver

from je_load_density import parameter_resolver, resolve

parameter_resolver.set_variable("base", "https://api.example.com")
parameter_resolver.set_variables({"token": "abc", "tenant": "acme"})
parameter_resolver.add_csv_source("users", "users.csv")
parameter_resolver.clear()

expanded = resolve({"url": "${var.base}/login", "id": "${uuid()}"})

Public helpers

from je_load_density import (
    register_variable, register_variables,
    register_csv_source, register_csv_sources,
    resolve,
)

register_variable("base", "https://api.example.com")
register_variables({"tenant": "acme", "token": "abc"})

register_csv_source("users", "users.csv")
register_csv_sources([
    {"name": "products", "file_path": "products.csv", "cycle": False},
])

payload = resolve({
    "url": "${var.base}/login",
    "json": {"email": "${csv.users.email}",
             "password": "${csv.users.password}"},
})

Supported placeholders

Placeholder	Resolves to
`${var.NAME}`	Value passed to `register_variable(s)`.
`${env.NAME}`	Environment variable `NAME`.
`${csv.SOURCE.COLUMN}`	Next row of CSV source `SOURCE` (cycles by default).
`${faker.METHOD}`	Calls `Faker().METHOD()` (lazy import).
`${uuid()}`	New UUID 4 string.
`${now()}`	Local ISO-8601 timestamp (seconds).
`${randint(min, max)}`	Cryptographically-strong random int in `[min, max]`.

Extractors

Tasks may declare extract rules; matching values are written back into the resolver under the chosen variable name. Sources: json_path, header, status_code.

{
  "method": "post",
  "request_url": "${var.base}/login",
  "extract": [
    {"var": "auth_token", "from": "json_path", "path": "data.token"},
    {"var": "request_id", "from": "header",    "name": "X-Request-Id"}
  ]
}

Subsequent tasks can read ${var.auth_token} straight from the resolver.

Action-JSON commands

Command	Summary
`LD_register_variable` / `LD_register_variables`	Register one or many `${var.x}` values.
`LD_register_csv_source` / `LD_register_csv_sources`	Bind a CSV file to a `${csv.name.col}` source.
`LD_clear_resolver`	Reset every registered variable / source.