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|
{-# LANGUAGE DeriveAnyClass #-}
{-# LANGUAGE QuasiQuotes #-}
module OpenlabTools where
import Builder
import Control.Category qualified as Cat
import Control.Concurrent.STM hiding (atomically, readTVarIO)
import Control.DeepSeq (NFData, deepseq)
import Control.Monad.Except (runExcept, throwError)
import Control.Monad.Logger qualified as Logger
import Control.Monad.Logger.CallStack
import Control.Monad.Reader
import Data.Attoparsec.ByteString qualified as Atto
import Data.CaseInsensitive qualified as CaseInsensitive
import Data.Either (partitionEithers)
import Data.Error.Tree
import Data.Functor (($>))
import Data.HashMap.Strict qualified as HashMap
import Data.List qualified as List
import Data.List.NonEmpty qualified as NonEmpty
import Data.Maybe (listToMaybe, maybeToList)
import Data.Monoid qualified as Monoid
import Data.Text qualified as Text
import Data.Time (NominalDiffTime, UTCTime (utctDayTime), diffUTCTime, getCurrentTime)
import Data.Time qualified as Time
import Data.Time.Clock (addUTCTime)
import Data.Time.Format qualified as Time.Format
import Debug.Trace
import FieldParser (FieldParser' (..))
import FieldParser qualified as Field
import GHC.Stack qualified
import IHP.HSX.QQ (hsx)
import Label
import MyLabel
import MyPrelude
import Network.HTTP.Client.Conduit qualified as Http
import Network.HTTP.Simple qualified as Http
import Network.HTTP.Types qualified as Http
import Network.Wai qualified as Wai
import Network.Wai.Handler.Warp qualified as Warp
import OpenTelemetry.Trace qualified as Otel hiding (getTracer, inSpan, inSpan')
import OpenTelemetry.Trace.Core qualified as Otel hiding (inSpan, inSpan')
import OpenTelemetry.Trace.Monad qualified as Otel
import Parse (Parse, mkParseNoContext, mkParsePushContext)
import Parse qualified
import System.Environment qualified as Env
import System.IO qualified as IO
import Text.Blaze.Html.Renderer.Pretty qualified as Html.Pretty
import Text.Blaze.Html.Renderer.Utf8 qualified as Html
import Text.Blaze.Html5 qualified as Html
import Text.HTML.TagSoup qualified as Soup
import Text.HTML.TagSoup.Tree qualified as SoupTree
import Text.StringLike qualified as Soup
import UnliftIO hiding (Handler, newTVarIO)
import Prelude hiding (span, until)
-- | Link to the https://mapall.space heatmap for the OpenLab Augsburg
mapallSpaceOla :: Text
mapallSpaceOla = "https://mapall.space/heatmap/show.php?id=OpenLab+Augsburg"
-- | Link to the OpenLab Augsburg wiki page containing the calendar html
openlabWikiCalendar :: Text
openlabWikiCalendar = "https://wiki.openlab-augsburg.de"
mainPage :: Html.Html
mainPage =
Html.docTypeHtml
[hsx|
<head>
<title>Openlab Augsburg Tools</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
</head>
<body>
<p>Welcome to the OpenLab Augsburg tools thingy. The idea is to provide some services that can be embedded into our other pages.</p>
<h2>What’s there</h2>
<ul>
<li>
A <a href="snips/table-opening-hours-last-week">table displaying the opening hours last week</a>, courtesy of <a href={mapallSpaceOla}>mapall.space</a>.
</li>
<li>
An <a href="events/openlab-augsburg-recurring-events.ics"><code>.ical</code> calendar file</a> for recurring events in the OpenLab, generated from the <code><span></code>s on the <a href="https://wiki.openlab-augsburg.de/">frontpage of our Wiki</a>. (Something wrong with the ical file? Check out the <a href="events/debug.html">debug section</a>.)
</li>
</ul>
<h2>Show me the code/how to contribute</h2>
<p>The source code can be found <a href="https://code.tvl.fyi/tree/users/Profpatsch/openlab-tools">in my user dir in the tvl repo</a>.</p>
<p>To build the server, clone the repository from <a href="https://code.tvl.fyi/depot.git">https://code.tvl.fyi/depot.git</a>.
Then <code>cd</code> into <code>users/Profpatsch</code>, run <code>nix-shell</code>.
</p>
<p>You can now run the server with <code>cabal repl openlab-tools/`</code> by executing the <code>main</code> function inside the GHC repl. It starts on port <code>9099</code>.
<br>
To try out changes to the code, stop the server with <kbd><kbd>Ctrl</kbd>+<kbd>c</kbd></kbd> and type <code>:reload</code>, then <code>main</code> again.
<br>
Finally, from within <code>users/Profpatsch</code> you can start a working development environment by installing <var>vscode</var> or <var>vscodium</var> and the <var>Haskell</var> extension. Then run <code>code .</code> from within the directory.
</p>
<p>Once you have a patch, <a href="https://matrix.to/#/@profpatsch:augsburg.one">contact me on Matrix</a> or DM me at <code>irc/libera</code>, nick <code>Profpatsch</code>.
</p>
</body>
|]
debug :: Bool
debug = False
-- | Run the given application; can be used to test functions that return 'AppT'.
mainWith :: AppT IO a -> IO a
mainWith appT = withTracer $ \tracer -> do
runReaderT appT.unAppT Context {..}
-- Run the app.
main :: IO ()
main = mainWith $ do
let runApplication ::
(MonadUnliftIO m, MonadLogger m) =>
( Wai.Request ->
(Wai.Response -> m Wai.ResponseReceived) ->
m Wai.ResponseReceived
) ->
m ()
runApplication app = do
withRunInIO $ \runInIO -> Warp.run 9099 $ \req respond -> do
let catchAppException act =
try act >>= \case
Right a -> pure a
Left (AppException err) -> do
runInIO (logError err)
respond (Wai.responseLBS Http.status500 [] "")
liftIO $ catchAppException (runInIO $ app req (\resp -> liftIO $ respond resp))
runHandlers
runApplication
appHandlers
-- | App handlers
appHandlers :: [Handler (AppT IO)]
appHandlers = do
[ Handler
{ path = "",
body =
Body
(pure ())
(\((), _) -> pure $ ok200Html [] (renderHtml mainPage))
},
Handler
{ path = "snips/table-opening-hours-last-week",
body =
Body
((label @"ifModifiedSince" <$> parseIfModifiedSince))
( \(req', cache) -> do
now <- liftIO getCurrentTime <&> mkSecondTime
new <- updateCacheIfNewer now cache heatmap
let cacheToHeaders =
[ ("Last-Modified", new.lastModified & formatHeaderTime),
("Expires", new.until & formatHeaderTime),
( "Cache-Control",
let maxAge = new.until `diffSecondTime` now
in [fmt|max-age={maxAge & floor @NominalDiffTime @Int & show}, immutable|]
)
]
if
-- If the last cache update is newer or equal to the requested version, we can tell the browser it’s fine
| Just modifiedSince <- req'.ifModifiedSince,
modifiedSince >= new.lastModified ->
pure $ Wai.responseLBS Http.status304 cacheToHeaders ""
| otherwise ->
pure $ ok200Html cacheToHeaders (new.result & toLazyBytes)
)
},
Handler
{ path = "events/openlab-augsburg-recurring-events.ics",
body =
Body
(pure ())
( \(_req', _cache) -> do
cal <- readOpenlabWikiCalendar
pure $
Wai.responseLBS
Http.status200
[("Content-Type", "text/calendar")]
(cal.ical & textToBytesUtf8 & toLazyBytes)
)
},
Handler
{ path = "events/debug.html",
body =
Body
(pure ())
( \(_req', _cache) -> do
cal <- readOpenlabWikiCalendar
let html =
[hsx|
<!DOCTYPE html>
<head>
<title>Openlab Events Ical Debugging</title>
<meta charset="utf-8">
</head>
<body>
<h1>Ical error debugging</h1>
<p><a href="openlab-augsburg-recurring-events.ics">→ Kalenderlink</a></p>
<p>Ich habe gerade versucht, das <code>.ical</code> aus dem Wiki zu generieren, und die folgenden Events warfen Fehler:</p>
<pre>
{cal.err & prettyErrorTree}
</pre>
<p>Aber nicht alles ist verloren! Die folgenden Events konnten geparsed werden und ein Subset funktioniert eventuell, so sieht die <code>.ical</code> aus:</p>
<pre>
{cal.ical}
</pre>
</body>
|]
pure $
Wai.responseLBS
Http.status200
[("Content-Type", "text/html")]
(html & Html.renderHtml)
)
}
]
where
renderHtml =
if debug
then Html.Pretty.renderHtml >>> stringToText >>> textToBytesUtf8 >>> toLazyBytes
else Html.renderHtml
ok200Html extra res = Wai.responseLBS Http.ok200 (("Content-Type", "text/html") : extra) res
-- "https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Last-Modified#syntax"
headerFormat = "%a, %d %b %0Y %T GMT"
formatHeaderTime (SecondTime t) =
t
& Time.Format.formatTime
@UTCTime
Time.Format.defaultTimeLocale
headerFormat
& stringToText
& textToBytesUtf8
parseHeaderTime =
Field.utf8
>>> ( FieldParser $ \t ->
t
& textToString
& Time.Format.parseTimeM
@Maybe
@UTCTime
{-no leading whitespace -} False
Time.Format.defaultTimeLocale
headerFormat
& annotate [fmt|Cannot parse header timestamp "{t}"|]
)
parseIfModifiedSince :: Parse Wai.Request (Maybe SecondTime)
parseIfModifiedSince =
lmap
( (.requestHeaders)
>>> findMaybe
( \(h, v) ->
if "If-Modified-Since" == CaseInsensitive.mk h then Just v else Nothing
)
)
(Parse.maybe $ Parse.fieldParser parseHeaderTime)
& rmap (fmap mkSecondTime)
-- | Extract the heatmap from https://mapall.space
heatmap :: AppT IO ByteString
heatmap = do
Http.httpBS [fmt|GET {mapallSpaceOla}|]
<&> (.responseBody)
<&> Soup.parseTags
<&> Soup.canonicalizeTags
<&> findHeatmap
<&> fromMaybe (htmlToTags [hsx|<p>Uh oh! could not fetch the table from <a href={mapallSpaceOla}>{mapallSpaceOla}</a></p>|])
<&> Soup.renderTags
where
firstSection f t = t & Soup.sections f & listToMaybe
match :: Soup.Tag ByteString -> Soup.Tag ByteString -> Bool
match x (t :: Soup.Tag ByteString) = (Soup.~==) @ByteString t x
findHeatmap t =
t
& firstSection (match (Soup.TagOpen ("") [("class", "heatmap")]))
>>= firstSection (match (Soup.TagOpen "table" []))
<&> getTable
<&> (<> htmlToTags [hsx|<figcaption>source: <a href={mapallSpaceOla} target="_blank">mapall.space</a></figcaption>|])
<&> wrapTagStream (T2 (label @"el" "figure") (label @"attrs" []))
-- get the table from opening tag to closing tag (allowing nested tables)
getTable = go 0
where
go _ [] = []
go d (el : els)
| match (Soup.TagOpen "table" []) el = el : go (d + 1) els
| match (Soup.TagClose "table") el = if d <= 1 then [el] else el : go (traceShowId $ d - 1) els
| otherwise = el : go d els
htmlToTags :: Html.Html -> [Soup.Tag ByteString]
htmlToTags h = h & Html.renderHtml & toStrictBytes & Soup.parseTags
-- TODO: this is dog-slow because of the whole list recreation!
wrapTagStream ::
T2 "el" ByteString "attrs" [Soup.Attribute ByteString] ->
[Soup.Tag ByteString] ->
[Soup.Tag ByteString]
wrapTagStream tag inner = (Soup.TagOpen (tag.el) tag.attrs : inner) <> [Soup.TagClose tag.el]
-- | Read the OpenLab wiki calendar from the wiki page and parse it into a list of events.
readOpenlabWikiCalendar :: AppT IO (T2 "err" ErrorTree "ical" Text)
readOpenlabWikiCalendar =
Http.httpBS @(AppT IO)
( [fmt|GET {openlabWikiCalendar}|]
& Http.setRequestHeader "User-Agent" ["curl/8.11.1"]
& Http.setRequestHeader "Accept" ["text/html"]
)
<&> (.responseBody)
<&> Soup.parseTags
<&> Soup.canonicalizeTags
<&> findCalendarEntries
<&> map
( \calendarEntry -> do
let getAttr attrName = mkParsePushContext attrName $
\as -> as & List.lookup (attrName & textToBytesUtf8) & annotate [fmt|Missing span attribute {attrName}|]
let getAttrs attrName = mkParsePushContext attrName $
\as -> as & mapMaybe (\(k, v) -> v & guarded (textToBytesUtf8 attrName == k)) & pure
let attrs = Parse.name "<span> attributes" $ do
dataSince <- getAttr "data-since" >>> Parse.fieldParser (Field.utf8 >>> Field.hyphenatedDay)
dataStableId <- getAttr "data-stable-id" >>> Parse.fieldParser Field.utf8
dataAdditional <- getAttrs "data-additional" >>> Parse.multiple (Parse.fieldParser (Field.utf8 >>> Field.hyphenatedDay))
dataExcept <- getAttrs "data-except" >>> Parse.multiple (Parse.fieldParser (Field.utf8 >>> Field.hyphenatedDay))
pure (t3 #since dataSince #stableId dataStableId #excepts (t2 #additional dataAdditional #excepts dataExcept))
let dateSpec = Parse.name "<span> date spec" $ Parse.withFrom $ \spec ->
Parse.fieldParser $ attoparsecBytes' [fmt|error parsing dateSpec from: {spec & bytesToTextUtf8Lenient}|] parseDateSpec
let headerText =
( (findTagOneOf ["h1", "h2", "h3", "h4", "h5", "h6"] <&> toList)
>>>
-- ignore the toc-anchor tag
firstDirectTagText
( \case
SoupTree.TagBranch _ attrs' _ -> not $ classContains "toc-anchor" attrs'
_ -> True
)
)
let parser = do
span <- Parse.name "datespec <span>" $ do
attrs' <- lmap (.attrsSet) attrs
dateSpec' <- lmap (.spanText) dateSpec
pure $ t2 #attrs attrs' #dateSpec dateSpec'
heading <- lmap (.sectionTags) $ Parse.name "section heading" headerText
body <- lmap (.sectionTags) identity <&> skipTag
pure $
OpenlabWikiCalendarIcal
{ since = span.attrs.since,
stableId = span.attrs.stableId,
dateSpec = span.dateSpec,
additional = span.attrs.excepts.additional,
excepts = span.attrs.excepts.excepts,
heading,
body
}
Parse.runParse "Parse error when getting span tag" parser calendarEntry
& first
( \err ->
nestedMultiError
"Cannot parse calendar event"
$ err
:| [ nestedError
"The calender section we tried to parse was"
( calendarEntry.sectionTags
& Soup.renderTags
& bytesToTextUtf8Lenient
& newError
& singleError
)
]
)
)
<&> partitionEithers
<&> \(errs, events) ->
t2
#err
( case errs of
IsEmpty -> "No errors! :)"
IsNonEmpty e -> nestedMultiError "Errors when parsing these events from the wiki" e
)
#ical
(mkOpenlabWikiCalendarIcal events)
-- | Whether the class is in the class attribute
classContains :: Text -> [Soup.Attribute ByteString] -> Bool
classContains className attrs =
attrs
& List.lookup "class"
<&> (\val -> className `Text.isInfixOf` (val & bytesToTextUtf8Lenient))
& fromMaybe False
-- | Skip a single tag (forward until its closing tag), ignore nested tags of the same kind
--
-- TODO: unify with the <table> find above
skipTag :: forall str. (Soup.StringLike str) => [Soup.Tag str] -> [Soup.Tag str]
skipTag [] = []
skipTag (Soup.TagOpen name _ : more) = go name 0 more
where
go :: str -> Int -> [Soup.Tag str] -> [Soup.Tag str]
go _ _ [] = []
go n d (el : els)
| match (Soup.TagOpen n []) el = go n (d + 1) els
| match (Soup.TagClose n) el = if d <= 1 then els else go n (traceShowId $ d - 1) els
| otherwise = go n d els
match :: Soup.Tag str -> Soup.Tag str -> Bool
match x (t :: Soup.Tag str) = (Soup.~==) @str t x
skipTag ts = ts
-- | Get the first TagText content in the given subtree.
--
-- The @useSubtree@ filter can be used to filter out unwanted subtags.
firstDirectTagText :: (SoupTree.TagTree ByteString -> Bool) -> Parse [Soup.Tag ByteString] Text
firstDirectTagText useSubtree =
mkParseNoContext $
( \ts -> runExcept $ do
ts
& SoupTree.tagTree
-- We should be in a surrounding element now
& ( \case
[] -> throwError [fmt|Cannot find a subtree|]
(SoupTree.TagBranch _ _ children : _) -> pure children
_ -> throwError [fmt|Cannot find a subtree|]
)
<&> List.filter useSubtree
>>= \case
IsEmpty -> throwError [fmt|Cannot find tags to extract text|]
IsNonEmpty ts' ->
ts'
& toList
-- flatten again, find the first tag text
& SoupTree.flattenTree
& mapMaybe Soup.maybeTagText
<&> bytesToTextUtf8Lenient
-- ignore all only-whitespace text
<&> Text.strip
& List.filter ("" /=)
& \case
IsEmpty -> throwError [fmt|Cannot find any plain text element|]
IsNonEmpty a -> pure (NonEmpty.head a)
)
-- | Find the first tag content that is one of the list of given tag names.
-- Includes the opening and closing element.
findTagOneOf :: [Text] -> Parse [Soup.Tag ByteString] (NonEmpty (Soup.Tag ByteString))
findTagOneOf names =
Parse.mkParsePushContext [fmt|findTag[{names & Text.intercalate ","}]|] $ \tags -> runExcept $ do
let namesB = names & map textToBytesUtf8
tags
& \case
IsEmpty -> throwError [fmt|Empty list of tags|]
IsNonEmpty t -> pure t
<&> NonEmpty.tails1
<&> findMaybe
( \hs ->
if
| (Soup.TagOpen name' _) <- NonEmpty.head hs,
name' `List.elem` namesB ->
Just $ t2 #tagName name' #tags hs
| otherwise -> Nothing
)
>>= maybe (throwError [fmt|No tag found that are any of "{names & Text.intercalate ", "}"|]) pure
>>= ( \sect -> do
sect.tags
& NonEmpty.break
(Soup.isTagCloseName sect.tagName)
& \case
(inner, IsNonEmpty (end :| _)) -> pure $ NonEmpty.prependList inner $ singleton end
-- no closing tag found
(_inner, IsEmpty) -> throwError [fmt|No closing tag found for "{sect.tagName}"|]
)
-- | Find all calendar entries by their <span> tag in the wiki page, and their corresponding section tags.
findCalendarEntries ::
[Soup.Tag ByteString] ->
[T3 "attrsSet" [Soup.Attribute ByteString] "spanText" ByteString "sectionTags" [Soup.Tag ByteString]]
findCalendarEntries tags =
tags
& headerSections
-- get everything till the end of this heading
& mapMaybe (\sect -> getFirstTagName sect <&> \name -> onlyThisHead name sect)
-- find the datespec
& mapMaybe
( \sect ->
sect
& overNonEmpty findDatespecSpan
<&> ( \t ->
t3
#attrsSet
t.attrsSet
#spanText
t.spanText
#sectionTags
sect
)
)
where
isHeader t =
any
($ t)
[ Soup.isTagOpenName "h1",
Soup.isTagOpenName "h2",
Soup.isTagOpenName "h3",
Soup.isTagOpenName "h4",
Soup.isTagOpenName "h5",
Soup.isTagOpenName "h6"
]
-- all sections that start with a header tag
headerSections = Soup.sections isHeader
-- everything until the next header that matches the given tag
onlyThisHead headerName ts =
ts
& Soup.partitions
-- break on any header that is on the same level or bigger
-- (e.g. if we are a h2, break on h2 and h1)
(\t -> any (\h -> Soup.isTagOpenName h t) (upperHeaders headerName))
& headMay
& maybeToList
& join
-- headers that have a bigger powerlevel than the given header
upperHeaders h = ["h6", "h5", "h4", "h3", "h2", "h1"] & List.dropWhile (/= h)
getFirstTagName =
findMaybe
( \case
(Soup.TagOpen name _) -> Just name
_ -> Nothing
)
-- find a <span>-tag like <span data-since="2025-01-01">Th[1] 19:00+</span>
findDatespecSpan ::
NonEmpty (Soup.Tag ByteString) ->
Maybe
(T2 "attrsSet" [Soup.Attribute ByteString] "spanText" ByteString)
findDatespecSpan ts =
ts
-- We need the info whether there is another header before the span
-- But ignore the first element since it’s always a header
& (\(t :| ts') -> t2 #acc mempty #dat t :| zipWithFold (Monoid.Any . isHeader) ts')
-- Get the first datespec span tag in this section
& NonEmpty.tails1
& findMaybe
( \ts'' -> do
let h = NonEmpty.head ts''
let headerTag = h.dat
let leadingHeader = h.acc
if
-- if we find another header before the datespec, this is not a datespec header section (prevents duplicates)
| Monoid.Any True <- leadingHeader -> Nothing
| Soup.TagOpen name attrsSet <- headerTag,
name == "span",
Just _ <- List.lookup "data-datespec" attrsSet ->
Just $
t2
#attrsSet
attrsSet
#tags
(headerTag :| NonEmpty.tail (ts'' <&> (.dat)))
| otherwise -> Nothing
)
<&> ( \sect ->
t2
#attrsSet
sect.attrsSet
#spanText
( sect.tags
& NonEmpty.tail
& List.takeWhile (not . Soup.isTagCloseName "span")
& Soup.innerText
)
)
-- \| Zip the given accumulation over the list along with the original list items
zipWithFold :: (Monoid m) => (a -> m) -> [a] -> [T2 "acc" m "dat" a]
zipWithFold f as =
zipWith
(\m a -> t2 #acc m #dat a)
(List.scanl' (\b a -> f a <> b) mempty as)
as
-- | Parse a dateSpec, which accepts a (very) small subset of the OpenStreetMap `opening_hours` tag,
-- see https://wiki.openstreetmap.org/wiki/Key:opening_hours
parseDateSpec :: Atto.Parser DateSpec
parseDateSpec = dayTime
where
-- wd weekday, available: Mo · Tu · We · Th · Fr · Sa · Su Fr 08:30-20:00
-- hh hour, always two digits number in 24 hour basis (no am/pm), in the format "hh:mm" · Fr 08:30-20:00
-- mm minute, always two digits number in the format "hh:mm" Fr 08:30-20:00
-- mo month, available: Jan · Feb · Mar · Apr · May · Jun · Jul · Aug · Sep · Oct · Nov · Dec · "mo md" Dec 25
-- md monthday, always two digits number in the format · "mo md" Dec 25
-- we week number, always a two digit number in range 01-53, in the format "week we" week 25 Mo 08:30-20:00
n = flip (Atto.<?>)
charLit c = Atto.word8 (charToWordUnsafe c) <|> fail [fmt|required char '{c}'|]
oneOfErr :: [(a, Text)] -> Atto.Parser a
oneOfErr ps =
Atto.choice (ps <&> (\(a, t) -> a <$ (Atto.string $ textToBytesUtf8 t)))
<|> fail [fmt|Must be one of {ps <&> snd & show}|]
weekday = n "weekday" $ oneOfErr $ (\t -> (t, t)) <$> ["Mo", "Tu", "We", "Th", "Fr", "Sa", "Su"]
optionalMonthOffset = n "optionalMonthOffset" $ do
starts <- Atto.option False (charLit '[' $> True)
if starts
then
Just <$> do
isNeg <- Atto.option False (True <$ charLit '-')
offset <-
Atto.choice $
( [1 .. 6 :: Int] <&> \i -> do
Atto.string (buildBytes intDecimalB i)
pure i
)
<|> fail "Must be between [-6] and [+6] (excluding 0)"
charLit ']'
pure $ if isNeg then -offset else offset
else pure Nothing
oneOfIntPadTwo ints = oneOfErr $ (\i -> (i, buildText (padPrefixT 2 '0' naturalDecimalT) i)) <$> ints
hour = n "hour" $ oneOfIntPadTwo [0 .. 23]
minute = n "minute" $ oneOfIntPadTwo [0 .. 59]
hhMm = n "hh:mm" $ do
h <- hour
Atto.word8 (charToWordUnsafe ':')
m <- minute
pure $ HhMm {hour = h, minute = m}
hhMmMinusHhMm = n "hh:mm-hh:mm" $ do
start <- hhMm
Atto.word8 (charToWordUnsafe '-')
end <- hhMm
pure (start, end)
startTime =
n "startTime" $
(n "startTimeEoD" $ StartTimeEoD <$> (hhMm <* charLit '+'))
<|> (StartTimeEndTime <$> hhMmMinusHhMm)
<|> fail "Must be in the format hh:mm-hh:mm or hh:mm+ (from time until end of day)"
dayTime :: Atto.Parser DateSpec
dayTime = n "dayTime" $ do
w <- weekday
offset <- optionalMonthOffset
charLit ' '
hhmm <- startTime
pure $ DateSpec {weekday = w, offset = offset, startTime = hhmm}
data DateSpec = DateSpec
{ -- | The weekday this events happens, @Mo@, @Tu@, @We@, @Th@, @Fr@, @Sa@, @Su@
weekday :: Text,
-- | If this is not set, the event happens every week; if set, it happens once per month in the given week (1 = first week, -1 = last week, 3 = third week, etc.)
offset :: Maybe Int,
-- | The start time of the event in the given day
startTime :: StartTime
}
deriving stock (Show, Eq)
-- | The start time of the event in the given day
data StartTime
= -- | has a start and end hour, formatted as @hh:mm-hh:mm@
StartTimeEndTime (HhMm, HhMm)
| -- | has a start hour and ends at the end of the day, formatted as @hh:mm@
StartTimeEoD HhMm
deriving stock (Show, Eq)
-- | Some examples of datespecs that should parse.
testParseDateSpec :: IO ()
testParseDateSpec = do
let specs =
[ "Mo[1] 19:00-23:00",
"Mo[-1] 19:00+",
"Mo 15:00"
]
for_ specs $ \dateSpec -> do
let result = Field.runFieldParser (attoparsecBytes' [fmt|error parsing dateSpec from: {dateSpec & bytesToTextUtf8Lenient}|] parseDateSpec) dateSpec
print result
-- | Turn Attoparsec parser into FieldParser, and keep the attoparsec error message.
attoparsecBytes' :: Text -> Atto.Parser a -> FieldParser' Error ByteString a
attoparsecBytes' err parser =
let parseAll = Atto.parseOnly (parser <* Atto.endOfInput)
in FieldParser $ \bytes -> case parseAll bytes of
Left attoErr -> Left $ attoErr & stringToText & newError & errorContext err
Right a -> Right a
-- | Ical data for one of our recurring events
data OpenlabWikiCalendarIcal = OpenlabWikiCalendarIcal
{ since :: Time.Day,
stableId :: Text,
dateSpec :: DateSpec,
excepts :: [Time.Day],
additional :: [Time.Day],
heading :: Text,
body :: [Soup.Tag ByteString]
}
-- | Generate an iCal file from the given list of events.
mkOpenlabWikiCalendarIcal ::
[OpenlabWikiCalendarIcal] ->
Text
mkOpenlabWikiCalendarIcal dat =
[fmt|{openlabWikiCalendarIcalHeader :: Text}
{icalEvents :: Text}
END:VCALENDAR
|]
where
icalEvents =
dat
& concatMap icalEvent
& Text.intercalate "\n"
icalEvent (d :: OpenlabWikiCalendarIcal) = do
let mkStarttime day = case d.dateSpec.startTime of
StartTimeEndTime (start, _) -> mkIcalDateTime day start
StartTimeEoD start -> mkIcalDateTime day start
let mkEndtime day = case d.dateSpec.startTime of
StartTimeEndTime (_, end) -> mkIcalDateTime day end
StartTimeEoD _ -> mkIcalDateTime day (HhMm {hour = 23, minute = 59})
let since = d.since & Time.showGregorian
let rrule = case d.dateSpec.offset of
-- every week per month
Nothing -> Just [fmt|FREQ=WEEKLY;BYDAY={d.dateSpec.weekday & Text.toUpper}|]
-- once per month on the offset week
Just offset -> Just [fmt|FREQ=MONTHLY;BYDAY={d.dateSpec.weekday & Text.toUpper};BYSETPOS={offset & buildText intDecimalT}|]
let summary = d.heading
-- We create a unique recurring event for the combination of identifier & since date
let uid = [fmt|{d.stableId :: Text}-since-{since}|]
let descriptionText = d.body & Soup.innerText & bytesToTextUtf8Lenient
let descriptionHtml =
d.body
& Soup.renderTags
& bytesToTextUtf8Lenient
let mkDtstamp day = mkIcalDateTime day hhMmZero
mkIcalEvent
<$> concat
[ pure $
IcalEvent
{ summary,
uid,
descriptionText,
descriptionHtml,
-- we use a DTSTAMP that corresponds to midnight of `since`, so clients should update if that changes? Although our UID also includes `since`, so unsure.
dtstamp = mkDtstamp d.since,
starttime = mkStarttime d.since,
recurrenceId = Nothing,
endtime = mkEndtime d.since,
rrule,
-- here we remove events in the chain that should not happen (has to be the exact start date & time of each event, so we use mkStarttime)
excepts = d.excepts <&> \e -> mkStarttime e
},
-- for each additional event we want to add to the chain, add a single event that references the original
d.additional
<&> \day ->
IcalEvent
{ summary,
-- same uid as the event chain
uid,
descriptionText,
descriptionHtml,
dtstamp = mkDtstamp day,
starttime = mkStarttime day,
-- \| We set the recurrence to the starttime of the original event
recurrenceId = Just (mkStarttime d.since),
endtime = mkEndtime day,
rrule = Nothing,
excepts = []
}
]
-- | An hour/minute timestamp
data HhMm = HhMm
{ hour :: Natural,
minute :: Natural
}
deriving stock (Show, Eq)
hhMmZero :: HhMm
hhMmZero = HhMm {hour = 0, minute = 0}
-- | Create an iCal date time in the format @yyyymmddThhmmss@
mkIcalDateTime :: Time.Day -> HhMm -> Text
mkIcalDateTime day hhmm =
day & Time.toGregorian & \(y, m, d) ->
[fmt|{y}{pad2 m}{pad2 d}T{hhmm & hhMmToIcalTime}|]
where
pad2 = buildText (padPrefixT 2 '0' intDecimalT)
-- | Convert a HhMm to the iCal time format @hhmmss@
hhMmToIcalTime :: HhMm -> Text
hhMmToIcalTime (HhMm h m) = do
let pad2 = buildText (padPrefixT 2 '0' naturalDecimalT)
[fmt|{h & pad2}{m & pad2}00|]
-- | escapes an ical TEXT value, also strips leading/trailing whitespace
escapeIcalText :: Text -> Text
escapeIcalText =
Text.strip
>>> Text.replace "\\" "\\\\"
>>> Text.replace ";" "\\;"
>>> Text.replace "," "\\,"
>>> Text.replace "\n" "\\n"
-- | A standard VCALENDAR header for our calendar file, including the timezone definition.
openlabWikiCalendarIcalHeader :: Text
openlabWikiCalendarIcalHeader =
[fmt|BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//openlab.augsburg.de/recurring-events//de-DE
NAME:Openlab Augsburg Wiederkehrende Events
X-WR-CALNAME:Openlab Augsburg Wiederkehrende Events
CALSCALE:GREGORIAN
X-WR-TIMEZONE:Europe/Berlin
X-PUBLISHED-TTL:P1H
BEGIN:VTIMEZONE
TZID:Europe/Berlin
X-LIC-LOCATION:Europe/Berlin
BEGIN:STANDARD
TZOFFSETFROM:+0200
TZOFFSETTO:+0100
TZNAME:CET
DTSTART:19701025T030000
RRULE:FREQ=YEARLY;BYMONTH=10;BYDAY=-1SU
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:+0100
TZOFFSETTO:+0200
TZNAME:CEST
DTSTART:19700329T020000
RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=-1SU
END:DAYLIGHT
END:VTIMEZONE|]
-- | Data to create a single iCal event
data IcalEvent = IcalEvent
{ summary :: Text,
uid :: Text,
descriptionText :: Text,
descriptionHtml :: Text,
dtstamp :: Text,
starttime :: Text,
-- | If this event is an override to a recurring event, this is the original start-time of the event in the series, see https://icalendar.org/iCalendar-RFC-5545/3-8-4-4-recurrence-id.html
recurrenceId :: Maybe Text,
endtime :: Text,
-- | if the event should repeat, and how
rrule :: Maybe Text,
-- | Dates when the (recurring) event should not happen
excepts :: [Text]
}
deriving stock (Show, Eq)
{-
BEGIN:VEVENT
UID:project-deadline-20240105@example.com
SUMMARY:Project Deadline
DTSTART;TZID=Europe/Berlin:20240105T235900
DTEND;TZID=Europe/Berlin:20240106T000000
DESCRIPTION:Final deadline for project submission
RRULE:FREQ=MONTHLY;BYMONTHDAY=5
END:VEVENT
-}
exampleIcalEvent :: Text
exampleIcalEvent =
mkIcalEvent $
IcalEvent
{ summary = "Project Deadline",
uid = "project-deadline-20240105@example.com",
descriptionText = "Final deadline for project submission",
descriptionHtml = "<p>Final deadline for project submission",
dtstamp = "20240105T000000",
starttime = "20240105T235900",
recurrenceId = Nothing,
endtime = "20240106T000000",
rrule = Just "FREQ=MONTHLY;BYMONTHDAY=5",
excepts = []
}
-- | Create an iCal event from the given data.
mkIcalEvent ::
IcalEvent ->
Text
mkIcalEvent dat =
[fmt|BEGIN:VEVENT
UID:{dat.uid :: Text}
SUMMARY:{escapeIcalText dat.summary :: Text}
DTSTAMP:{dat.dtstamp :: Text}
DTSTART;TZID=Europe/Berlin:{dat.starttime :: Text}
DTEND;TZID=Europe/Berlin:{dat.endtime :: Text}
DESCRIPTION:{escapeIcalText dat.descriptionText :: Text}
{optionalRules :: Text }
END:VEVENT|]
where
optionalRules =
mintersperse ("\n" :: Text) $
join $
[ dat.rrule & ifExists (\rrule -> [fmt|RRULE:{rrule :: Text}|] :: Text),
dat.excepts <&> \e -> [fmt|EXDATE;TZID=Europe/Berlin:{e :: Text}|],
dat.recurrenceId & ifExists (\recId -> [fmt|RECURRENCE-ID;TZID=Europe/Berlin:{recId :: Text}|])
]
-- X-ALT-DESC:{escapeIcalText dat.descriptionHtml :: Text}
data Handler m = Handler
{ path :: Text,
body :: Body m
}
-- | A request Body is a parser for the request object and a function that receives a parsed request
-- and a cache with potentially previously cached results.
data Body m
= forall a.
Body
(Parse Wai.Request a)
((a, TVar (Cache ByteString)) -> m Wai.Response)
-- | Turn a list of handlers into something that slots into a "Network.Wai" Application.
runHandlers ::
(Otel.MonadTracer m, MonadUnliftIO m, MonadThrow m) =>
( (Wai.Request -> (Wai.Response -> m a) -> m a) ->
m ()
) ->
[Handler m] ->
m ()
runHandlers runApplication handlers = do
withCaches ::
[ T2
"handler"
(Handler m)
"cache"
(TVar (Cache ByteString))
] <-
handlers
& traverse
( \h -> do
cache <- liftIO $ newCache h.path "nothing yet"
pure $ T2 (label @"handler" h) (label @"cache" cache)
)
runApplication $ \req respond -> do
let mHandler =
withCaches
& List.find
( \h ->
(h.handler.path)
== (req & Wai.pathInfo & Text.intercalate "/")
)
case mHandler of
Nothing -> respond $ Wai.responseLBS Http.status404 [] "nothing here (yet)"
Just handler -> do
inSpan' "TODO" $ \span -> do
case handler.handler.body of
Body parse runHandler -> do
req' <- req & parseRequest span parse
resp <- runHandler (req', handler.cache)
respond resp
where
parseRequest :: (MonadThrow f) => Otel.Span -> Parse from a -> from -> f a
parseRequest span parser req =
Parse.runParse "Unable to parse the HTTP request" parser req
& assertM span id
inSpan :: (MonadUnliftIO m, Otel.MonadTracer m) => Text -> m a -> m a
inSpan name = Otel.inSpan name Otel.defaultSpanArguments
inSpan' :: Text -> (Otel.Span -> m a) -> m a
-- inSpan' name = Otel.inSpan' name Otel.defaultSpanArguments
inSpan' _name act = act (error "todo telemetry disabled")
-- | Assert the given function returns Right, and throw the error if it fails.
assertM :: (MonadThrow f) => Otel.Span -> (t -> Either ErrorTree a) -> t -> f a
assertM span f v = case f v of
Right a -> pure a
Left err -> appThrowTree span err
-- | UTC time that is only specific to the second
newtype SecondTime = SecondTime {unSecondTime :: UTCTime}
deriving newtype (Show, Eq, Ord)
mkSecondTime :: UTCTime -> SecondTime
mkSecondTime utcTime = SecondTime utcTime {utctDayTime = Time.secondsToDiffTime $ floor utcTime.utctDayTime}
diffSecondTime :: SecondTime -> SecondTime -> NominalDiffTime
diffSecondTime (SecondTime a) (SecondTime b) = diffUTCTime a b
-- | A cache entry that contains the name of the cache,
-- the time until it is valid, the last modified time, and the cached result.
data Cache a = Cache
{ name :: !Text,
until :: !SecondTime,
lastModified :: !SecondTime,
result :: !a
}
deriving stock (Show)
-- | Create cache from a name and an initial result.
newCache :: Text -> a -> IO (TVar (Cache a))
newCache name result = do
let until = mkSecondTime $ Time.UTCTime {utctDay = Time.ModifiedJulianDay 1, utctDayTime = 1}
let lastModified = until
newTVarIO $ Cache {..}
-- | Update the cache with a new result, unconditionally.
updateCache :: (NFData a, Eq a) => SecondTime -> TVar (Cache a) -> a -> STM (Cache a)
updateCache now cache result' = do
-- make sure we don’t hold onto the world by deepseq-ing and evaluating to WHNF
let !result = deepseq result' result'
let until = mkSecondTime $ (5 * 60) `addUTCTime` now.unSecondTime
!toWrite <- do
old <- readTVar cache
let name = old.name
-- only update the lastModified time iff the content changed (this is helpful for HTTP caching with If-Modified-Since)
if old.result == result
then do
let lastModified = old.lastModified
pure $ Cache {..}
else do
let lastModified = now
pure $ Cache {..}
_ <- writeTVar cache $! toWrite
pure toWrite
-- | Run the given action iff the cache is stale, otherwise just return the item from the cache.
updateCacheIfNewer :: (MonadUnliftIO m, NFData b, Eq b) => SecondTime -> TVar (Cache b) -> m b -> m (Cache b)
updateCacheIfNewer now cache act = withRunInIO $ \runInIO -> do
old <- readTVarIO cache
if old.until < now
then do
res <- runInIO act
atomically $ updateCache now cache res
else pure old
-- | Setup the otel tracer
withTracer :: (Otel.Tracer -> IO c) -> IO c
withTracer f = do
setDefaultEnv "OTEL_SERVICE_NAME" "whatcd-resolver"
bracket
-- Install the SDK, pulling configuration from the environment
Otel.initializeGlobalTracerProvider
-- Ensure that any spans that haven't been exported yet are flushed
Otel.shutdownTracerProvider
-- Get a tracer so you can create spans
(\tracerProvider -> f $ Otel.makeTracer tracerProvider "whatcd-resolver" Otel.tracerOptions)
where
setDefaultEnv :: String -> String -> IO ()
setDefaultEnv envName defaultValue = do
Env.lookupEnv envName >>= \case
Just _env -> pure ()
Nothing -> Env.setEnv envName defaultValue
-- | App environment
data Context = Context
{ tracer :: Otel.Tracer
}
-- | A wrapper around our context environment
newtype AppT m a = AppT {unAppT :: ReaderT Context m a}
deriving newtype (Functor, Applicative, Monad, MonadIO, MonadUnliftIO, MonadThrow)
-- | Application exception, thrown by the @appThrow*@ functions
data AppException = AppException Text
deriving stock (Show)
deriving anyclass (Exception)
-- | A specialized variant of @addEvent@ that records attributes conforming to
-- the OpenTelemetry specification's
-- <https://github.com/open-telemetry/opentelemetry-specification/blob/49c2f56f3c0468ceb2b69518bcadadd96e0a5a8b/specification/trace/semantic_conventions/exceptions.md semantic conventions>
--
-- @since 0.0.1.0
recordException ::
( MonadIO m,
HasField "message" r Text,
HasField "type_" r Text
) =>
Otel.Span ->
r ->
m ()
recordException span dat = liftIO $ do
callStack <- GHC.Stack.whoCreated dat.message
newEventTimestamp <- Just <$> Otel.getTimestamp
Otel.addEvent span $
Otel.NewEvent
{ newEventName = "exception",
newEventAttributes =
HashMap.fromList
[ ("exception.type", Otel.toAttribute @Text dat.type_),
("exception.message", Otel.toAttribute @Text dat.message),
("exception.stacktrace", Otel.toAttribute @Text $ Text.unlines $ map stringToText callStack)
],
..
}
-- | Throw the given error tree as app exception, and record it in the span
appThrowTree :: (MonadThrow m) => Otel.Span -> ErrorTree -> m a
appThrowTree _span exc = do
let msg = prettyErrorTree exc
-- recordException
-- span
-- ( T2
-- (label @"type_" "AppException")
-- (label @"message" msg)
-- )
throwM $ AppException msg
-- | If Left, throw the given error tree as app exception, and record it in the span
orAppThrowTree :: (MonadThrow m) => Otel.Span -> Either ErrorTree a -> m a
orAppThrowTree span = \case
Left err -> appThrowTree span err
Right a -> pure a
instance (MonadIO m) => MonadLogger (AppT m) where
monadLoggerLog loc src lvl msg = liftIO $ Logger.defaultOutput IO.stderr loc src lvl (Logger.toLogStr msg)
instance (Monad m) => Otel.MonadTracer (AppT m) where
getTracer = AppT $ asks (.tracer)
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