942e05ba3e
Parses manifest.launcher.md leading JSON-frontmatter (delimited by standalone '---' lines), returns (meta, body). Reuses lib-management.dep-fetcher._json_decode so we do not add a second JSON decoder to the codebase. Lazy require so test-lib contexts can swap a stub decoder via _G.LAUNCHER_FRONTMATTER_DECODER.
64 lines
2.3 KiB
Lua
64 lines
2.3 KiB
Lua
-- frontmatter.lua — JSON-Frontmatter parser for manifest.launcher.md
|
|
-- Splits on the first standalone '---' line. Everything before goes to
|
|
-- depf._json_decode; everything after (after a single LF) is body.
|
|
-- Loud-Error semantics: parse failure returns nil + err-string.
|
|
|
|
local M = {}
|
|
|
|
-- depf is required lazily so this file can be dofile'd into a test-lib
|
|
-- context where lib-management.dep-fetcher is not on the dep list. The
|
|
-- launcher main module does require it eagerly; the test-lib monkeys
|
|
-- a stub decoder into _G before calling fm.parse.
|
|
local function get_decoder()
|
|
if _G.LAUNCHER_FRONTMATTER_DECODER then
|
|
return _G.LAUNCHER_FRONTMATTER_DECODER
|
|
end
|
|
local ok, depf = pcall(require, "lib-management.dep-fetcher")
|
|
if ok and depf and depf._json_decode then return depf._json_decode end
|
|
return nil
|
|
end
|
|
|
|
-- Splits the content at the first line equal to '---'. The first such
|
|
-- line ends the JSON region; lines before it are JSON, lines after
|
|
-- are body. Both regions are LF-joined back into strings.
|
|
local function split_at_separator(content)
|
|
local lines = {}
|
|
for line in (content .. "\n"):gmatch("([^\n]*)\n") do
|
|
lines[#lines + 1] = line
|
|
end
|
|
-- A valid file starts with '---' (no leading whitespace).
|
|
if lines[1] ~= "---" then return nil end
|
|
local sep_idx = nil
|
|
for i = 2, #lines do
|
|
if lines[i] == "---" then sep_idx = i; break end
|
|
end
|
|
if not sep_idx then return nil end
|
|
local json_lines = {}
|
|
for i = 2, sep_idx - 1 do json_lines[#json_lines + 1] = lines[i] end
|
|
local body_lines = {}
|
|
for i = sep_idx + 1, #lines do body_lines[#body_lines + 1] = lines[i] end
|
|
return table.concat(json_lines, "\n"), table.concat(body_lines, "\n")
|
|
end
|
|
|
|
function M.parse(content)
|
|
if type(content) ~= "string" then
|
|
return nil, nil, "frontmatter.parse: content must be string"
|
|
end
|
|
local json_str, body = split_at_separator(content)
|
|
if not json_str then
|
|
-- No frontmatter — treat the whole content as body, empty meta.
|
|
return {}, content
|
|
end
|
|
local decode = get_decoder()
|
|
if not decode then
|
|
return nil, nil, "frontmatter.parse: no JSON decoder available"
|
|
end
|
|
local meta, derr = decode(json_str)
|
|
if not meta then
|
|
return nil, nil, "frontmatter.parse: " .. tostring(derr)
|
|
end
|
|
return meta, body
|
|
end
|
|
|
|
return M
|