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| 1 | +{-# LANGUAGE OverloadedStrings #-} |
| 2 | + |
| 3 | +module Main (main) where |
| 4 | + |
| 5 | +import Control.Exception |
| 6 | +import Data.List (find) |
| 7 | +import qualified Data.Text as T |
| 8 | +import qualified Data.Text.IO as T |
| 9 | +import Sql2er.Common.Types |
| 10 | +import Sql2er.Parser (parseSqlScript) |
| 11 | +import System.Exit (exitFailure) |
| 12 | +import Text.Megaparsec |
| 13 | +import Sql2er.ERDiagram (renderErDiagram) |
| 14 | +import Sql2er.CmdArgs (Options(..), parseCmdArgs) |
| 15 | + |
| 16 | +-- This function will find all the create table statements, |
| 17 | +-- alter or drop the tables based on statements. |
| 18 | +postParsingSetup :: [Statement] -> [Table] -> [Table] |
| 19 | +postParsingSetup [] r = r |
| 20 | +postParsingSetup (statement : statements) resTable = do |
| 21 | + case statement of |
| 22 | + AlterStatement alterStatement -> do |
| 23 | + let alteredTableName = alterTableName alterStatement |
| 24 | + let actions = action alterStatement |
| 25 | + case find (\x -> alteredTableName == tableName x) resTable of |
| 26 | + Nothing -> postParsingSetup statements resTable -- Table name of alter statement not found |
| 27 | + Just alteringTable -> do |
| 28 | + let res = applyAlteration alteringTable actions |
| 29 | + newList = removeElem alteringTable resTable |
| 30 | + postParsingSetup statements (res : newList) |
| 31 | + DropStatement dropStatement -> postParsingSetup statements (dropTables (tableNames dropStatement) resTable) |
| 32 | + CreateStatement s -> postParsingSetup statements (s : resTable) |
| 33 | + CreateTypeStatement _ -> postParsingSetup statements resTable |
| 34 | + EOF -> postParsingSetup statements resTable |
| 35 | + where |
| 36 | + dropTables :: [TableName] -> [Table] -> [Table] |
| 37 | + dropTables tNames = filter (\t -> tableName t `notElem` tNames) |
| 38 | + |
| 39 | + applyAlterAction :: Table -> AlterTableAction -> Table |
| 40 | + applyAlterAction alteringTable act = do |
| 41 | + case act of |
| 42 | + RenameColumn oldCol newCol -> do |
| 43 | + case find (\x -> oldCol == columnName x) (columns alteringTable) of |
| 44 | + Nothing -> alteringTable |
| 45 | + Just col -> do |
| 46 | + let listWithoutElem = removeElem col (columns alteringTable) |
| 47 | + listWithNewElem = (col {columnName = newCol}) : listWithoutElem |
| 48 | + alteringTable {columns = listWithNewElem} |
| 49 | + AddColumn col -> alteringTable {columns = col : columns alteringTable} |
| 50 | + DropColumn col _ -> do |
| 51 | + case find (\x -> col == columnName x) (columns alteringTable) of |
| 52 | + Nothing -> alteringTable |
| 53 | + Just col0 -> alteringTable {columns = removeElem col0 (columns alteringTable)} |
| 54 | + RenameTable newTableName -> alteringTable {tableName = newTableName} |
| 55 | + SetSchema schemaName -> alteringTable {tableName = schemaName <> "." <> tableName alteringTable} |
| 56 | + AlterColumnSetType colName sqlType mDefaultVal -> do |
| 57 | + case find (\x -> colName == columnName x) (columns alteringTable) of |
| 58 | + Nothing -> alteringTable |
| 59 | + Just col -> do |
| 60 | + let listWithoutElem = removeElem col (columns alteringTable) |
| 61 | + let listWithNewElem = |
| 62 | + case mDefaultVal of |
| 63 | + Nothing -> (col {columnType = sqlType}) : listWithoutElem |
| 64 | + Just dVal -> do |
| 65 | + let newCConstraints = |
| 66 | + removeElemP |
| 67 | + ( \x -> |
| 68 | + case x of |
| 69 | + (Default _) -> True |
| 70 | + _ -> False |
| 71 | + ) |
| 72 | + (cConstraints col) |
| 73 | + ( col |
| 74 | + { columnType = sqlType |
| 75 | + , cConstraints = Default dVal : newCConstraints |
| 76 | + } |
| 77 | + ) |
| 78 | + : listWithoutElem |
| 79 | + alteringTable {columns = listWithNewElem} |
| 80 | + AlterColumnSetDefault colName dVal -> do |
| 81 | + case find (\x -> colName == columnName x) (columns alteringTable) of |
| 82 | + Nothing -> alteringTable |
| 83 | + Just col -> do |
| 84 | + let listWithoutElem = removeElem col (columns alteringTable) |
| 85 | + let newCConstraints = |
| 86 | + removeElemP |
| 87 | + ( \x -> |
| 88 | + case x of |
| 89 | + (Default _) -> True |
| 90 | + _ -> False |
| 91 | + ) |
| 92 | + (cConstraints col) |
| 93 | + let listWithNewElem = col {cConstraints = Default dVal : newCConstraints} : listWithoutElem |
| 94 | + alteringTable {columns = listWithNewElem} |
| 95 | + AlterColunmnDropDefault colName -> do |
| 96 | + case find (\x -> colName == columnName x) (columns alteringTable) of |
| 97 | + Nothing -> alteringTable |
| 98 | + Just col -> do |
| 99 | + let listWithoutElem = removeElem col (columns alteringTable) |
| 100 | + let newCConstraints = |
| 101 | + removeElemP |
| 102 | + ( \x -> |
| 103 | + case x of |
| 104 | + (Default _) -> True |
| 105 | + _ -> False |
| 106 | + ) |
| 107 | + (cConstraints col) |
| 108 | + alteringTable {columns = (col {cConstraints = newCConstraints}) : listWithoutElem} |
| 109 | + AlterColumnSetNotNull colName -> do |
| 110 | + case find (\x -> colName == columnName x) (columns alteringTable) of |
| 111 | + Nothing -> alteringTable |
| 112 | + Just col -> do |
| 113 | + let listWithoutElem = removeElem col (columns alteringTable) |
| 114 | + alteringTable |
| 115 | + { columns = (col {cConstraints = NotNull : (cConstraints col)}) : listWithoutElem |
| 116 | + } |
| 117 | + AlterColumnDropNotNull colName -> do |
| 118 | + case find (\x -> colName == columnName x) (columns alteringTable) of |
| 119 | + Nothing -> alteringTable |
| 120 | + Just col -> do |
| 121 | + let listWithoutElem = removeElem col (columns alteringTable) |
| 122 | + let newCConstraints = |
| 123 | + removeElemP |
| 124 | + ( \x -> |
| 125 | + case x of |
| 126 | + NotNull -> True |
| 127 | + _ -> False |
| 128 | + ) |
| 129 | + (cConstraints col) |
| 130 | + alteringTable |
| 131 | + { columns = (col {cConstraints = newCConstraints}) : listWithoutElem |
| 132 | + } |
| 133 | + AddTableConstraint tConstraint -> |
| 134 | + alteringTable |
| 135 | + { tableConstraints = tConstraint : tableConstraints alteringTable |
| 136 | + } |
| 137 | + DropTableConstriant _ -> alteringTable -- Cannot implement since we are not tracking constraint name |
| 138 | + RenameConstraint _ _ -> alteringTable -- Cannot implement since we are not tracking constraint name |
| 139 | + applyAlteration :: Table -> [AlterTableAction] -> Table |
| 140 | + applyAlteration = foldl applyAlterAction |
| 141 | + |
| 142 | +removeElemP :: (a -> Bool) -> [a] -> [a] |
| 143 | +removeElemP p lst = helper lst [] |
| 144 | + where |
| 145 | + helper [] res = res |
| 146 | + helper (x : xs) res = if p x then res ++ xs else helper xs (x : res) |
| 147 | + |
| 148 | +removeElem :: Eq a => a -> [a] -> [a] |
| 149 | +removeElem ele lst = helper lst [] |
| 150 | + where |
| 151 | + helper [] res = res |
| 152 | + helper (x : xs) res = if ele == x then res ++ xs else helper xs (x : res) |
| 153 | + |
| 154 | +main :: IO () |
| 155 | +main = do |
| 156 | + opts <- parseCmdArgs |
| 157 | + content <- T.toLower |
| 158 | + <$> T.readFile (sqlFile opts) |
| 159 | + `catch` ( \e -> do |
| 160 | + print (e :: SomeException) |
| 161 | + exitFailure |
| 162 | + ) |
| 163 | + case parse parseSqlScript "sql parser" content of |
| 164 | + Left _ -> putStrLn "parsing failed :(" |
| 165 | + Right r -> do |
| 166 | + let tableList = postParsingSetup r [] |
| 167 | + renderErDiagram |
| 168 | + (outputFile opts) |
| 169 | + (width opts) |
| 170 | + (height opts) |
| 171 | + tableList |
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