Mercurial > urweb

annotate demo/batchFun.ur @ 2297:6d56080f495c

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Fix a read-after-free bug using a timestamp check
author Adam Chlipala <adam@chlipala.net>
date Thu, 19 Nov 2015 13:18:58 -0500
parents e6bc6bbd7a32
children
rev   line source
adamc@1002 1 con colMeta = fn (db :: Type, state :: Type) =>
adamc@650 2 {Nam : string,
adamc@1002 3 Show : db -> xbody,
adamc@1002 4 Inject : sql_injectable db,
adamc@650 5
adamc@1002 6 NewState : transaction state,
adamc@1002 7 Widget : state -> xbody,
adamc@1002 8 ReadState : state -> transaction db}
adam@1302 9 con colsMeta = fn cols => $(map colMeta cols)
adamc@650 10
adamc@823 11 fun default [t] (sh : show t) (rd : read t) (inj : sql_injectable t)
adamc@650 12 name : colMeta (t, source string) =
adamc@650 13 {Nam = name,
adamc@650 14 Show = txt,
adamc@650 15 Inject = _,
adamc@650 16
adamc@650 17 NewState = source "",
adamc@650 18 Widget = fn s => <xml><ctextbox source={s}/></xml>,
adamc@650 19 ReadState = fn s => v <- get s; return (readError v)}
adamc@650 20
adamc@650 21 val int = default
adamc@650 22 val float = default
adamc@650 23 val string = default
adamc@650 24
adamc@650 25 functor Make(M : sig
adamc@650 26 con cols :: {(Type * Type)}
adamc@650 27 constraint [Id] ~ cols
adamc@650 28 val fl : folder cols
adamc@650 29
adamc@706 30 table tab : ([Id = int] ++ map fst cols)
adamc@650 31
adamc@650 32 val title : string
adamc@650 33
adamc@650 34 val cols : colsMeta cols
adamc@650 35 end) = struct
adamc@650 36
adamc@650 37 val t = M.tab
adamc@650 38
adamc@650 39 datatype list t = Nil | Cons of t * list t
adamc@650 40
adamc@650 41 fun allRows () =
adamc@650 42 query (SELECT * FROM t)
adamc@650 43 (fn r acc => return (Cons (r.T, acc)))
adamc@650 44 Nil
adamc@650 45
adamc@650 46 fun add r =
adamc@650 47 dml (insert t
adamc@1093 48 (@foldR2 [fst] [colMeta]
adam@1778 49 [fn cols => $(map (fn t => sql_exp [] [] [] t.1) cols)]
adam@1302 50 (fn [nm :: Name] [t ::_] [rest ::_] [[nm] ~ rest] input col acc =>
adamc@1093 51 acc ++ {nm = @sql_inject col.Inject input})
adamc@1093 52 {} M.fl (r -- #Id) M.cols
adamc@1093 53 ++ {Id = (SQL {[r.Id]})}))
adamc@650 54
adamc@650 55 fun doBatch ls =
adamc@650 56 case ls of
adamc@650 57 Nil => return ()
adamc@650 58 | Cons (r, ls') =>
adamc@650 59 add r;
adamc@650 60 doBatch ls'
adamc@650 61
adamc@650 62 fun del id =
adamc@650 63 dml (DELETE FROM t WHERE t.Id = {[id]})
adamc@650 64
adamc@650 65 fun show withDel lss =
adamc@650 66 let
adamc@650 67 fun show' ls =
adamc@650 68 case ls of
adamc@650 69 Nil => <xml/>
adamc@650 70 | Cons (r, ls) => <xml>
adamc@650 71 <tr>
adamc@650 72 <td>{[r.Id]}</td>
adamc@1172 73 {@mapX2 [colMeta] [fst] [_]
adam@1302 74 (fn [nm :: Name] [p ::_] [rest ::_] [[nm] ~ rest] m v =>
adamc@1093 75 <xml><td>{m.Show v}</td></xml>)
adamc@1093 76 M.fl M.cols (r -- #Id)}
adamc@650 77 {if withDel then
adam@1784 78 <xml><td><button value="Delete" onclick={fn _ => rpc (del r.Id)}/></td></xml>
adamc@650 79 else
adamc@650 80 <xml/>}
adamc@650 81 </tr>
adamc@650 82 {show' ls}
adamc@650 83 </xml>
adamc@650 84 in
adamc@650 85 <xml><dyn signal={ls <- signal lss; return <xml><table>
adamc@650 86 <tr>
adamc@650 87 <th>Id</th>
adam@1641 88 {@mapX [colMeta] [tr]
adam@1302 89 (fn [nm :: Name] [p ::_] [rest ::_] [[nm] ~ rest] m =>
adamc@1093 90 <xml><th>{[m.Nam]}</th></xml>)
adamc@1093 91 M.fl M.cols}
adamc@650 92 </tr>
adamc@650 93 {show' ls}
adamc@650 94 </table></xml>}/></xml>
adamc@650 95 end
adamc@650 96
adamc@650 97 fun main () =
adamc@650 98 lss <- source Nil;
adamc@650 99 batched <- source Nil;
adamc@650 100
adamc@650 101 id <- source "";
adamc@1093 102 inps <- @foldR [colMeta] [fn r => transaction ($(map snd r))]
adam@1302 103 (fn [nm :: Name] [p ::_] [rest ::_] [[nm] ~ rest] m acc =>
adamc@1093 104 s <- m.NewState;
adamc@1093 105 r <- acc;
adamc@1093 106 return ({nm = s} ++ r))
adamc@1093 107 (return {})
adamc@1093 108 M.fl M.cols;
adamc@1093 109
adamc@650 110 let
adamc@650 111 fun add () =
adamc@650 112 id <- get id;
adamc@1093 113 vs <- @foldR2 [colMeta] [snd] [fn r => transaction ($(map fst r))]
adam@1302 114 (fn [nm :: Name] [p ::_] [rest ::_] [[nm] ~ rest] m s acc =>
adamc@1093 115 v <- m.ReadState s;
adamc@1093 116 r <- acc;
adamc@1093 117 return ({nm = v} ++ r))
adamc@1093 118 (return {})
adamc@1093 119 M.fl M.cols inps;
adamc@650 120 ls <- get batched;
adamc@650 121
adamc@650 122 set batched (Cons ({Id = readError id} ++ vs, ls))
adamc@650 123
adamc@650 124 fun exec () =
adamc@650 125 ls <- get batched;
adamc@650 126
adamc@908 127 rpc (doBatch ls);
adamc@650 128 set batched Nil
adamc@650 129 in
adamc@650 130 return <xml><body>
adamc@650 131 <h2>Rows</h2>
adamc@650 132
adamc@650 133 {show True lss}
adamc@650 134
adam@1784 135 <button value="Update" onclick={fn _ => ls <- rpc (allRows ()); set lss ls}/><br/>
adamc@650 136 <br/>
adamc@650 137
adamc@650 138 <h2>Batch new rows to add</h2>
adamc@650 139
adamc@650 140 <table>
adamc@650 141 <tr> <th>Id:</th> <td><ctextbox source={id}/></td> </tr>
adamc@1172 142 {@mapX2 [colMeta] [snd] [_]
adam@1302 143 (fn [nm :: Name] [p ::_] [rest ::_] [[nm] ~ rest] m s =>
adamc@1093 144 <xml><tr> <th>{[m.Nam]}:</th> <td>{m.Widget s}</td> </tr></xml>)
adamc@1093 145 M.fl M.cols inps}
adam@1784 146 <tr> <th/> <td><button value="Batch it" onclick={fn _ => add ()}/></td> </tr>
adamc@650 147 </table>
adamc@650 148
adamc@650 149 <h2>Already batched:</h2>
adamc@650 150 {show False batched}
adam@1784 151 <button value="Execute" onclick={fn _ => exec ()}/>
adamc@650 152 </body></xml>
adamc@650 153 end
adamc@650 154
adamc@650 155 end