Parse catalog json from file

.gitignore

@@ -1,4 +1,3 @@
 .dbpassword
-sql/spamnoticer_init.sql
 todo
 dist-newstyle/

chan-delorean.cabal

@@ -65,7 +65,8 @@ executable chan-delorean
     main-is:          Backfill.hs
 
     -- Modules included in this executable, other than Main.
-    -- other-modules:
+    other-modules:
+                      JSONParsing
 
     -- LANGUAGE extensions used by modules in this package.
     -- other-extensions:
@@ -75,7 +76,10 @@ executable chan-delorean
                       aeson,
                       bytestring,
                       cmdargs,
-                      directory
+                      directory,
+                      filepath,
+                      containers,
+                      text
 
     -- Directories containing source files.
     hs-source-dirs:   src

sql/initialize.sql

@@ -72,6 +72,9 @@ CREATE INDEX posts_body_search_idx   ON posts USING GIN (body_search_index);
 CREATE INDEX posts_thread_id_idx     ON posts (thread_id);
 CREATE INDEX posts_board_post_id_idx ON posts (board_post_id);
 
+-- This is to optimize joins on thread_id and filtering/sorting by creation_time in 'posts' table.
+CREATE INDEX posts_thread_id_creation_time_idx ON posts (thread_id, creation_time);
+
 CREATE OR REPLACE FUNCTION update_post_body_search_index() RETURNS trigger AS $$
 BEGIN
     NEW.body_search_index := to_tsvector('english', NEW.body);

src/Backfill.hs

@@ -5,11 +5,15 @@
 module Main where
 
 import System.Exit
+import Control.Monad (filterM)
 import Data.Aeson (FromJSON, decode)
 import qualified Data.ByteString.Lazy as B
 import System.Console.CmdArgs
 import GHC.Generics
-import System.Directory (listDirectory)
+import System.Directory (listDirectory, doesFileExist)
+import System.FilePath ((</>))
+
+import JSONParsing
 
 data SettingsCLI = SettingsCLI
   { jsonFile :: FilePath
@@ -29,10 +33,39 @@ settingsCLI = SettingsCLI
     } &= summary "Backfill v0.0.1"
 
 
--- Function to list all files and directories inside the backup_read_root
-listBackupContents :: JSONSettings -> IO ()
-listBackupContents settings =
-   listDirectory (backup_read_root settings) >>= mapM_ print
+listCatalogDirectories :: JSONSettings -> IO [FilePath]
+listCatalogDirectories settings = do
+    dirs <- listDirectory (backup_read_root settings)
+    filterM hasCatalog dirs
+  where
+    hasCatalog dir = do
+      let catalogPath = (backup_read_root settings) </> dir </> "catalog.json"
+      doesFileExist catalogPath
+
+
+processBackupDirectory :: JSONSettings -> IO ()
+processBackupDirectory settings = do
+    putStrLn "JSON successfully read!"
+    print settings  -- print the decoded JSON settings
+    dirs <- listCatalogDirectories settings
+    mapM_ print dirs
+    mapM_ processDir dirs
+  where
+    backupDir :: FilePath
+    backupDir = backup_read_root settings
+
+    processDir dir = do
+        let catalogPath = backupDir </> dir </> "catalog.json"
+        putStrLn $ "catalog file path: " ++ catalogPath
+
+        result <- parseJSONFile catalogPath
+
+        case result of
+            Right catalogs ->
+                mapM_ (mapM_ (print . no) . threads) catalogs
+            Left errMsg    ->
+                putStrLn $ "Failed to parse the JSON file in directory: "
+                    ++ dir ++ ". Error: " ++ errMsg
 
 main :: IO ()
 main = do
@@ -49,7 +82,4 @@ main = do
             Nothing -> do
                 putStrLn "Error: Invalid JSON format."
                 exitFailure
-            Just settings -> do
-                putStrLn "JSON successfully read!"
-                print settings  -- print the decoded JSON settings
-                listBackupContents settings
+            Just settings -> processBackupDirectory settings

src/JSONParsing.hs

@@ -0,0 +1,79 @@
+module JSONParsing
+    ( Thread(..)
+    , File(..)
+    , Catalog(..)
+    , parseJSONFile
+    ) where
+
+{-# LANGUAGE DeriveGeneric #-}
+{-# LANGUAGE OverloadedStrings #-}
+
+import Data.Aeson
+import GHC.Generics
+import qualified Data.ByteString.Lazy as B
+import qualified Data.Text as T
+import Data.Aeson.Types (typeMismatch)
+
+data Cyclical = Cyclical Int deriving (Show, Generic)
+
+instance FromJSON Cyclical where
+    parseJSON (Number n) = return $ Cyclical (floor n)
+    parseJSON (String s) =
+      case reads (T.unpack s) :: [(Int, String)] of
+      [(n, "")] -> return $ Cyclical n
+      _         -> typeMismatch "Int or String containing Int" (String s)
+
+    parseJSON invalid    = typeMismatch "Int or String" invalid
+
+data Thread = Thread
+  { no            :: Int
+  , sub           :: Maybe String
+  , com           :: Maybe String
+  , name          :: Maybe String
+  , capcode       :: Maybe String
+  , time          :: Int
+  , omitted_posts :: Maybe Int
+  , omitted_images:: Maybe Int
+  , replies       :: Maybe Int
+  , images        :: Maybe Int
+  , sticky        :: Maybe Int
+  , locked        :: Maybe Int
+  , cyclical      :: Maybe Cyclical
+  , last_modified :: Int
+  , board         :: String
+  , files         :: Maybe [File]
+  , resto         :: Int
+  , unique_ips    :: Maybe Int
+  } deriving (Show, Generic)
+
+data File = File
+  { id         :: String
+  , mime       :: String
+  , ext        :: String
+  , h          :: Maybe Int
+  , w          :: Maybe Int
+  , fsize      :: Int
+  , filename   :: String
+  , spoiler    :: Maybe Bool
+  , md5        :: String
+  , file_path  :: String
+  , thumb_path :: String
+  } deriving (Show, Generic)
+
+data Catalog = Catalog
+  { threads :: [Thread]
+  , page    :: Int
+  } deriving (Show, Generic)
+
+instance FromJSON Thread
+--instance ToJSON Thread
+instance FromJSON File
+--instance ToJSON File
+instance FromJSON Catalog
+--instance ToJSON Catalog
+
+
+parseJSONFile :: FilePath -> IO (Either String [Catalog])
+parseJSONFile path = do
+    jsonData <- B.readFile path
+    return $ eitherDecode jsonData