diff options
Diffstat (limited to 'pandoc-lua-engine/src/Text/Pandoc/Lua/Module')
| -rw-r--r-- | pandoc-lua-engine/src/Text/Pandoc/Lua/Module/Pandoc.hs | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/pandoc-lua-engine/src/Text/Pandoc/Lua/Module/Pandoc.hs b/pandoc-lua-engine/src/Text/Pandoc/Lua/Module/Pandoc.hs index 7c0408d63..56cb52910 100644 --- a/pandoc-lua-engine/src/Text/Pandoc/Lua/Module/Pandoc.hs +++ b/pandoc-lua-engine/src/Text/Pandoc/Lua/Module/Pandoc.hs @@ -30,6 +30,8 @@ import HsLua import System.Exit (ExitCode (..)) import Text.Pandoc.Class ( PandocMonad, FileInfo (..), FileTree , addToFileTree, getCurrentTime + , getRequestHeaders, getResourcePath, getUserDataDir + , setRequestHeaders, setResourcePath, setUserDataDir , insertInFileTree, sandboxWithFileTree ) import Text.Pandoc.Definition @@ -301,6 +303,37 @@ functions = <#> parameter peekFilter "Filter" "lua_filter" "filter functions" =#> functionResult pushInline "Inline" "modified Inline" + , defun "with_state" + ### with_state + <#> parameter peekStateOptions "table" "options" "state options" + <#> parameter pure "function" "callback" + "The action to run with the given state." + =?> "The results of the call to *callback*." + #? "Runs a function with a modified pandoc state.\n\ + \\n\ + \The given callback is invoked after setting the pandoc state to the\ + \ given values. The modifiable options are restored to their original\ + \ values once the callback has returned.\n\ + \\n\ + \The following state variables can be controlled:\n\ + \\n\ + \ - `request_headers` (list of key-value tuples)\n\ + \ - `resource_path` (list of filepaths)\n\ + \ - `user_data_dir` (string)\n\ + \\n\ + \Other options are ignored, and the rest of the state is not modified.\n\ + \\n\ + \Usage:\n\ + \\n\ + \ local opts = {\n\ + \ request_headers = {\n\ + \ {'Authorization', 'Basic my-secret'}\n\ + \ }\n\ + \ }\n\ + \ pandoc.with_state(opts, function ()\n\ + \ local mime, contents = pandoc.mediabag.fetch(image_url)\n\ + \ )\n" + , defun "write" ### (\doc mformatspec mwriterOpts -> unPandocLua $ do flvrd <- maybe (parseFlavoredFormat "markdown") pure mformatspec @@ -436,3 +469,61 @@ peekReadEnv idx = do -- Return ersatz file system. pure tree2 + +-- | Helper type that holds all common state values that can be controlled. +-- +-- This is closely related to "CommonState", but that's an opaque value +-- that can only be read and modified through accessor functions. All +-- fields in this type can be modified through accessors. +data StateOptions = StateOptions + { stateOptsRequestHeaders :: [(T.Text, T.Text)] + , stateOptsResourcePath :: [String] + , stateOptsUserDataDir :: Maybe String + } + +-- | Peek pandoc state options; the current state properties are used for +-- unspecified values. +peekStateOptions :: Peeker PandocError StateOptions +peekStateOptions idx = do + opts <- liftLua getStateOptions + let peekStateField field defVal peeker = + peekFieldRaw (fmap (fromMaybe defVal) . peekNilOr peeker) field idx + let peekOptStateField field defVal peeker = + peekFieldRaw (fmap (maybe defVal Just ) . peekNilOr peeker) field idx + StateOptions + <$> peekStateField "request_headers" + (stateOptsRequestHeaders opts) + (peekList (peekPair peekText peekText)) + <*> peekStateField "resource_path" + (stateOptsResourcePath opts) + (peekList peekString) + <*> peekOptStateField "user_data_dir" + (stateOptsUserDataDir opts) + peekString + +-- | Get the current options values from the pandoc state. +getStateOptions :: LuaE PandocError StateOptions +getStateOptions = unPandocLua $ StateOptions + <$> getRequestHeaders + <*> getResourcePath + <*> getUserDataDir + +-- | Update the pandoc state with the new options. +setStateOptions :: StateOptions -> LuaE PandocError () +setStateOptions opts = unPandocLua $ do + setRequestHeaders $ stateOptsRequestHeaders opts + setResourcePath $ stateOptsResourcePath opts + setUserDataDir $ stateOptsUserDataDir opts + +-- | Run a callback with a modified pandoc state. +with_state :: StateOptions -> StackIndex -> LuaE PandocError NumResults +with_state options callback_idx = do + origState <- getStateOptions + setStateOptions options + -- Invoke the callback + oldTop <- gettop + pushvalue callback_idx + call 0 multret + newTop <- gettop + setStateOptions origState + return . NumResults . fromStackIndex $ newTop - oldTop |