diff options
| -rw-r--r-- | .gitignore | 2 | ||||
| -rw-r--r-- | COPYING | 373 | ||||
| -rw-r--r-- | Makefile | 19 | ||||
| -rw-r--r-- | README.md | 19 | ||||
| -rw-r--r-- | app/Main.hs | 23 | ||||
| -rw-r--r-- | flake.lock | 80 | ||||
| -rw-r--r-- | flake.nix | 25 | ||||
| -rw-r--r-- | fourmolu.yaml | 5 | ||||
| -rw-r--r-- | src/Common.hs | 71 | ||||
| -rw-r--r-- | src/Cron.hs | 138 | ||||
| -rw-r--r-- | src/Cron/Expr.hs | 21 | ||||
| -rw-r--r-- | src/Cron/Parser.hs | 88 | ||||
| -rw-r--r-- | src/Cron/Schedule.hs | 72 | ||||
| -rw-r--r-- | src/Intro.hs | 64 | ||||
| -rw-r--r-- | uncron.cabal | 65 |
15 files changed, 1065 insertions, 0 deletions
diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..6d7e2df --- /dev/null +++ b/.gitignore @@ -0,0 +1,2 @@ +dist-newstyle/ +result @@ -0,0 +1,373 @@ +Mozilla Public License Version 2.0 +================================== + +1. Definitions +-------------- + +1.1. "Contributor" + means each individual or legal entity that creates, contributes to + the creation of, or owns Covered Software. + +1.2. "Contributor Version" + means the combination of the Contributions of others (if any) used + by a Contributor and that particular Contributor's Contribution. + +1.3. "Contribution" + means Covered Software of a particular Contributor. + +1.4. "Covered Software" + means Source Code Form to which the initial Contributor has attached + the notice in Exhibit A, the Executable Form of such Source Code + Form, and Modifications of such Source Code Form, in each case + including portions thereof. + +1.5. "Incompatible With Secondary Licenses" + means + + (a) that the initial Contributor has attached the notice described + in Exhibit B to the Covered Software; or + + (b) that the Covered Software was made available under the terms of + version 1.1 or earlier of the License, but not also under the + terms of a Secondary License. + +1.6. "Executable Form" + means any form of the work other than Source Code Form. + +1.7. "Larger Work" + means a work that combines Covered Software with other material, in + a separate file or files, that is not Covered Software. + +1.8. "License" + means this document. + +1.9. "Licensable" + means having the right to grant, to the maximum extent possible, + whether at the time of the initial grant or subsequently, any and + all of the rights conveyed by this License. + +1.10. "Modifications" + means any of the following: + + (a) any file in Source Code Form that results from an addition to, + deletion from, or modification of the contents of Covered + Software; or + + (b) any new file in Source Code Form that contains any Covered + Software. + +1.11. "Patent Claims" of a Contributor + means any patent claim(s), including without limitation, method, + process, and apparatus claims, in any patent Licensable by such + Contributor that would be infringed, but for the grant of the + License, by the making, using, selling, offering for sale, having + made, import, or transfer of either its Contributions or its + Contributor Version. + +1.12. "Secondary License" + means either the GNU General Public License, Version 2.0, the GNU + Lesser General Public License, Version 2.1, the GNU Affero General + Public License, Version 3.0, or any later versions of those + licenses. + +1.13. "Source Code Form" + means the form of the work preferred for making modifications. + +1.14. "You" (or "Your") + means an individual or a legal entity exercising rights under this + License. For legal entities, "You" includes any entity that + controls, is controlled by, or is under common control with You. For + purposes of this definition, "control" means (a) the power, direct + or indirect, to cause the direction or management of such entity, + whether by contract or otherwise, or (b) ownership of more than + fifty percent (50%) of the outstanding shares or beneficial + ownership of such entity. + +2. License Grants and Conditions +-------------------------------- + +2.1. Grants + +Each Contributor hereby grants You a world-wide, royalty-free, +non-exclusive license: + +(a) under intellectual property rights (other than patent or trademark) + Licensable by such Contributor to use, reproduce, make available, + modify, display, perform, distribute, and otherwise exploit its + Contributions, either on an unmodified basis, with Modifications, or + as part of a Larger Work; and + +(b) under Patent Claims of such Contributor to make, use, sell, offer + for sale, have made, import, and otherwise transfer either its + Contributions or its Contributor Version. + +2.2. Effective Date + +The licenses granted in Section 2.1 with respect to any Contribution +become effective for each Contribution on the date the Contributor first +distributes such Contribution. + +2.3. Limitations on Grant Scope + +The licenses granted in this Section 2 are the only rights granted under +this License. No additional rights or licenses will be implied from the +distribution or licensing of Covered Software under this License. +Notwithstanding Section 2.1(b) above, no patent license is granted by a +Contributor: + +(a) for any code that a Contributor has removed from Covered Software; + or + +(b) for infringements caused by: (i) Your and any other third party's + modifications of Covered Software, or (ii) the combination of its + Contributions with other software (except as part of its Contributor + Version); or + +(c) under Patent Claims infringed by Covered Software in the absence of + its Contributions. + +This License does not grant any rights in the trademarks, service marks, +or logos of any Contributor (except as may be necessary to comply with +the notice requirements in Section 3.4). + +2.4. Subsequent Licenses + +No Contributor makes additional grants as a result of Your choice to +distribute the Covered Software under a subsequent version of this +License (see Section 10.2) or under the terms of a Secondary License (if +permitted under the terms of Section 3.3). + +2.5. Representation + +Each Contributor represents that the Contributor believes its +Contributions are its original creation(s) or it has sufficient rights +to grant the rights to its Contributions conveyed by this License. + +2.6. Fair Use + +This License is not intended to limit any rights You have under +applicable copyright doctrines of fair use, fair dealing, or other +equivalents. + +2.7. Conditions + +Sections 3.1, 3.2, 3.3, and 3.4 are conditions of the licenses granted +in Section 2.1. + +3. Responsibilities +------------------- + +3.1. Distribution of Source Form + +All distribution of Covered Software in Source Code Form, including any +Modifications that You create or to which You contribute, must be under +the terms of this License. You must inform recipients that the Source +Code Form of the Covered Software is governed by the terms of this +License, and how they can obtain a copy of this License. You may not +attempt to alter or restrict the recipients' rights in the Source Code +Form. + +3.2. Distribution of Executable Form + +If You distribute Covered Software in Executable Form then: + +(a) such Covered Software must also be made available in Source Code + Form, as described in Section 3.1, and You must inform recipients of + the Executable Form how they can obtain a copy of such Source Code + Form by reasonable means in a timely manner, at a charge no more + than the cost of distribution to the recipient; and + +(b) You may distribute such Executable Form under the terms of this + License, or sublicense it under different terms, provided that the + license for the Executable Form does not attempt to limit or alter + the recipients' rights in the Source Code Form under this License. + +3.3. Distribution of a Larger Work + +You may create and distribute a Larger Work under terms of Your choice, +provided that You also comply with the requirements of this License for +the Covered Software. If the Larger Work is a combination of Covered +Software with a work governed by one or more Secondary Licenses, and the +Covered Software is not Incompatible With Secondary Licenses, this +License permits You to additionally distribute such Covered Software +under the terms of such Secondary License(s), so that the recipient of +the Larger Work may, at their option, further distribute the Covered +Software under the terms of either this License or such Secondary +License(s). + +3.4. Notices + +You may not remove or alter the substance of any license notices +(including copyright notices, patent notices, disclaimers of warranty, +or limitations of liability) contained within the Source Code Form of +the Covered Software, except that You may alter any license notices to +the extent required to remedy known factual inaccuracies. + +3.5. Application of Additional Terms + +You may choose to offer, and to charge a fee for, warranty, support, +indemnity or liability obligations to one or more recipients of Covered +Software. However, You may do so only on Your own behalf, and not on +behalf of any Contributor. You must make it absolutely clear that any +such warranty, support, indemnity, or liability obligation is offered by +You alone, and You hereby agree to indemnify every Contributor for any +liability incurred by such Contributor as a result of warranty, support, +indemnity or liability terms You offer. You may include additional +disclaimers of warranty and limitations of liability specific to any +jurisdiction. + +4. Inability to Comply Due to Statute or Regulation +--------------------------------------------------- + +If it is impossible for You to comply with any of the terms of this +License with respect to some or all of the Covered Software due to +statute, judicial order, or regulation then You must: (a) comply with +the terms of this License to the maximum extent possible; and (b) +describe the limitations and the code they affect. Such description must +be placed in a text file included with all distributions of the Covered +Software under this License. Except to the extent prohibited by statute +or regulation, such description must be sufficiently detailed for a +recipient of ordinary skill to be able to understand it. + +5. Termination +-------------- + +5.1. The rights granted under this License will terminate automatically +if You fail to comply with any of its terms. However, if You become +compliant, then the rights granted under this License from a particular +Contributor are reinstated (a) provisionally, unless and until such +Contributor explicitly and finally terminates Your grants, and (b) on an +ongoing basis, if such Contributor fails to notify You of the +non-compliance by some reasonable means prior to 60 days after You have +come back into compliance. Moreover, Your grants from a particular +Contributor are reinstated on an ongoing basis if such Contributor +notifies You of the non-compliance by some reasonable means, this is the +first time You have received notice of non-compliance with this License +from such Contributor, and You become compliant prior to 30 days after +Your receipt of the notice. + +5.2. If You initiate litigation against any entity by asserting a patent +infringement claim (excluding declaratory judgment actions, +counter-claims, and cross-claims) alleging that a Contributor Version +directly or indirectly infringes any patent, then the rights granted to +You by any and all Contributors for the Covered Software under Section +2.1 of this License shall terminate. + +5.3. In the event of termination under Sections 5.1 or 5.2 above, all +end user license agreements (excluding distributors and resellers) which +have been validly granted by You or Your distributors under this License +prior to termination shall survive termination. + +************************************************************************ +* * +* 6. Disclaimer of Warranty * +* ------------------------- * +* * +* Covered Software is provided under this License on an "as is" * +* basis, without warranty of any kind, either expressed, implied, or * +* statutory, including, without limitation, warranties that the * +* Covered Software is free of defects, merchantable, fit for a * +* particular purpose or non-infringing. The entire risk as to the * +* quality and performance of the Covered Software is with You. * +* Should any Covered Software prove defective in any respect, You * +* (not any Contributor) assume the cost of any necessary servicing, * +* repair, or correction. This disclaimer of warranty constitutes an * +* essential part of this License. No use of any Covered Software is * +* authorized under this License except under this disclaimer. * +* * +************************************************************************ + +************************************************************************ +* * +* 7. Limitation of Liability * +* -------------------------- * +* * +* Under no circumstances and under no legal theory, whether tort * +* (including negligence), contract, or otherwise, shall any * +* Contributor, or anyone who distributes Covered Software as * +* permitted above, be liable to You for any direct, indirect, * +* special, incidental, or consequential damages of any character * +* including, without limitation, damages for lost profits, loss of * +* goodwill, work stoppage, computer failure or malfunction, or any * +* and all other commercial damages or losses, even if such party * +* shall have been informed of the possibility of such damages. This * +* limitation of liability shall not apply to liability for death or * +* personal injury resulting from such party's negligence to the * +* extent applicable law prohibits such limitation. Some * +* jurisdictions do not allow the exclusion or limitation of * +* incidental or consequential damages, so this exclusion and * +* limitation may not apply to You. * +* * +************************************************************************ + +8. Litigation +------------- + +Any litigation relating to this License may be brought only in the +courts of a jurisdiction where the defendant maintains its principal +place of business and such litigation shall be governed by laws of that +jurisdiction, without reference to its conflict-of-law provisions. +Nothing in this Section shall prevent a party's ability to bring +cross-claims or counter-claims. + +9. Miscellaneous +---------------- + +This License represents the complete agreement concerning the subject +matter hereof. If any provision of this License is held to be +unenforceable, such provision shall be reformed only to the extent +necessary to make it enforceable. Any law or regulation which provides +that the language of a contract shall be construed against the drafter +shall not be used to construe this License against a Contributor. + +10. Versions of the License +--------------------------- + +10.1. New Versions + +Mozilla Foundation is the license steward. Except as provided in Section +10.3, no one other than the license steward has the right to modify or +publish new versions of this License. Each version will be given a +distinguishing version number. + +10.2. Effect of New Versions + +You may distribute the Covered Software under the terms of the version +of the License under which You originally received the Covered Software, +or under the terms of any subsequent version published by the license +steward. + +10.3. Modified Versions + +If you create software not governed by this License, and you want to +create a new license for such software, you may create and use a +modified version of this License if you rename the license and remove +any references to the name of the license steward (except to note that +such modified license differs from this License). + +10.4. Distributing Source Code Form that is Incompatible With Secondary +Licenses + +If You choose to distribute Source Code Form that is Incompatible With +Secondary Licenses under the terms of this version of the License, the +notice described in Exhibit B of this License must be attached. + +Exhibit A - Source Code Form License Notice +------------------------------------------- + + This Source Code Form is subject to the terms of the Mozilla Public + License, v. 2.0. If a copy of the MPL was not distributed with this + file, You can obtain one at https://mozilla.org/MPL/2.0/. + +If it is not possible or desirable to put the notice in a particular +file, then You may include the notice in a location (such as a LICENSE +file in a relevant directory) where a recipient would be likely to look +for such a notice. + +You may add additional accurate notices of copyright ownership. + +Exhibit B - "Incompatible With Secondary Licenses" Notice +--------------------------------------------------------- + + This Source Code Form is "Incompatible With Secondary Licenses", as + defined by the Mozilla Public License, v. 2.0. diff --git a/Makefile b/Makefile new file mode 100644 index 0000000..2db5bff --- /dev/null +++ b/Makefile @@ -0,0 +1,19 @@ +.PHONY: format +format: + fourmolu -i app/ src/ + +.PHONY: lint +lint: + find {app,src}/ | entr -c hlint src/ app/ + +.PHONY: run +run: + find {app,src}/ | entr -cr cabal new-run uncron -- "* * * * *" + +.PHONY: build +build: + find {app,src}/ | entr -c cabal new-build uncron + +.PHONY: repl +repl: + ghcid --allow-eval --lint --command "cabal repl uncron" diff --git a/README.md b/README.md new file mode 100644 index 0000000..93e3f58 --- /dev/null +++ b/README.md @@ -0,0 +1,19 @@ +# uncron + +Convert cron schedules into a human-readable form: + + > uncron "0 6 1 * *" + At 06:00, on the 1st of every month + > uncron "0 * 2 1-4 *" + At the top of every hour, on the 2nd from January to April + > uncron "10,30,50 * 1 1-6/3 *" + At minutes 10, 30 and 50 of every hour, on the 1st of every 3 months from January to June + +## Building & Running + +The recommended solution is to use `nix`: + +- Use `nix profile install http://git.k.mulga.net/julien/uncron/snapshot/uncron-main.tar.gz` to install uncron, +- Use `nix run http://git.k.mulga.net/julien/uncron/snapshot/uncron-main.tar.gz` to build and run the binary directly. + +If you have `cabal` installed, use `cabal build` or `cabal install`. diff --git a/app/Main.hs b/app/Main.hs new file mode 100644 index 0000000..0b1f81e --- /dev/null +++ b/app/Main.hs @@ -0,0 +1,23 @@ +module Main (main) where + +import Control.Arrow (left) +import qualified Cron +import Intro +import System.Environment (getArgs) +import System.IO (getLine) + +main :: IO () +main = do + cron <- getCron + putStrLn . showOrErr $ Cron.toProse <$> (Cron.parse =<< cron) + +getCron :: IO (Either String String) +getCron = do + args <- getArgs + case args of + [] -> Right <$> getLine + [x] -> pure $ Right x + xs -> pure $ Left ("Too many inputs or invalid option: " ++ show xs) + +showOrErr :: Either String String -> String +showOrErr = either id id . left ("Error. " ++) diff --git a/flake.lock b/flake.lock new file mode 100644 index 0000000..e2626d9 --- /dev/null +++ b/flake.lock @@ -0,0 +1,80 @@ +{ + "nodes": { + "flake-parts": { + "inputs": { + "nixpkgs-lib": "nixpkgs-lib" + }, + "locked": { + "lastModified": 1709336216, + "narHash": "sha256-Dt/wOWeW6Sqm11Yh+2+t0dfEWxoMxGBvv3JpIocFl9E=", + "owner": "hercules-ci", + "repo": "flake-parts", + "rev": "f7b3c975cf067e56e7cda6cb098ebe3fb4d74ca2", + "type": "github" + }, + "original": { + "owner": "hercules-ci", + "repo": "flake-parts", + "type": "github" + } + }, + "haskell-flake": { + "locked": { + "lastModified": 1711568381, + "narHash": "sha256-IvVqTNcbSNh6XgyS4ikBkQio1eMmLvKTl3vAvkVPn+0=", + "owner": "srid", + "repo": "haskell-flake", + "rev": "5dcb739e9cc4e0edf5267de665fa7a905a543baa", + "type": "github" + }, + "original": { + "owner": "srid", + "repo": "haskell-flake", + "type": "github" + } + }, + "nixpkgs": { + "locked": { + "lastModified": 1711593151, + "narHash": "sha256-/9NCoPI7fqJIN8viONsY9X0fAeq8jc3GslFCO0ky6TQ=", + "owner": "nixos", + "repo": "nixpkgs", + "rev": "bb2b73df7bcfbd2dd55ff39b944d70547d53c267", + "type": "github" + }, + "original": { + "owner": "nixos", + "ref": "nixpkgs-unstable", + "repo": "nixpkgs", + "type": "github" + } + }, + "nixpkgs-lib": { + "locked": { + "dir": "lib", + "lastModified": 1709237383, + "narHash": "sha256-cy6ArO4k5qTx+l5o+0mL9f5fa86tYUX3ozE1S+Txlds=", + "owner": "NixOS", + "repo": "nixpkgs", + "rev": "1536926ef5621b09bba54035ae2bb6d806d72ac8", + "type": "github" + }, + "original": { + "dir": "lib", + "owner": "NixOS", + "ref": "nixos-unstable", + "repo": "nixpkgs", + "type": "github" + } + }, + "root": { + "inputs": { + "flake-parts": "flake-parts", + "haskell-flake": "haskell-flake", + "nixpkgs": "nixpkgs" + } + } + }, + "root": "root", + "version": 7 +} diff --git a/flake.nix b/flake.nix new file mode 100644 index 0000000..cc733a1 --- /dev/null +++ b/flake.nix @@ -0,0 +1,25 @@ +{ + inputs = { + nixpkgs.url = "github:nixos/nixpkgs/nixpkgs-unstable"; + flake-parts.url = "github:hercules-ci/flake-parts"; + haskell-flake.url = "github:srid/haskell-flake"; + }; + outputs = inputs@{ self, nixpkgs, flake-parts, ... }: + flake-parts.lib.mkFlake { inherit inputs; } { + systems = nixpkgs.lib.systems.flakeExposed; + imports = [ inputs.haskell-flake.flakeModule ]; + + perSystem = { self', pkgs, ... }: { + + haskellProjects.default = { + devShell = { + enable = true; + tools = hp: { fourmolu = hp.fourmolu; ghcid = hp.ghcid; }; + hlsCheck.enable = true; + }; + }; + + packages.default = self'.packages.uncron; + }; + }; +} diff --git a/fourmolu.yaml b/fourmolu.yaml new file mode 100644 index 0000000..ce46be3 --- /dev/null +++ b/fourmolu.yaml @@ -0,0 +1,5 @@ +column-limit: 100 +comma-style: leading +import-export-style: leading +indentation: 2 +respectful: false diff --git a/src/Common.hs b/src/Common.hs new file mode 100644 index 0000000..a196527 --- /dev/null +++ b/src/Common.hs @@ -0,0 +1,71 @@ +module Common ((?), (?:), fromDigits, leftPad, listToProse, asOrdinal, showDayOfWeek, showMonth) where + +import Data.List (replicate, take) +import Data.List.NonEmpty (NonEmpty ((:|))) +import Data.Maybe (fromMaybe) +import Intro + +fromDigits :: [Int] -> Int +fromDigits = foldl (\n d -> 10 * n + d) 0 + +leftPad :: Int -> a -> [a] -> [a] +leftPad m x xs = replicate (m - length ys) x ++ ys + where + ys = take m xs + +(?) :: Bool -> a -> a -> a +(?) True x _ = x +(?) False _ y = y + +infixr 1 ? + +(?:) :: Maybe a -> a -> a +maybeA ?: b = fromMaybe b maybeA + +infixr 0 ?: + +listToProse :: NonEmpty String -> String +listToProse (x :| xs) = mconcat . reverse $ proseJoin xs [x] + where + proseJoin [] ys = ys + proseJoin [y] [] = [y] + proseJoin [y] zs = y : " and " : zs + proseJoin (y : ys) zs = proseJoin ys (y : ", " : zs) + +asOrdinal :: Int -> String +asOrdinal 11 = "11th" +asOrdinal 12 = "12th" +asOrdinal 13 = "13th" +asOrdinal n = + show n ++ case n `mod` 10 of + 1 -> "st" + 2 -> "nd" + 3 -> "rd" + _ -> "th" + +showDayOfWeek :: Int -> Maybe String +showDayOfWeek = \case + 0 -> Just "Sunday" + 1 -> Just "Monday" + 2 -> Just "Tuesday" + 3 -> Just "Wednesday" + 4 -> Just "Thursday" + 5 -> Just "Friday" + 6 -> Just "Saturday" + _ -> Nothing + +showMonth :: Int -> Maybe String +showMonth = \case + 1 -> Just "January" + 2 -> Just "February" + 3 -> Just "March" + 4 -> Just "April" + 5 -> Just "May" + 6 -> Just "June" + 7 -> Just "July" + 8 -> Just "August" + 9 -> Just "September" + 10 -> Just "October" + 11 -> Just "November" + 12 -> Just "December" + _ -> Nothing diff --git a/src/Cron.hs b/src/Cron.hs new file mode 100644 index 0000000..3cadac9 --- /dev/null +++ b/src/Cron.hs @@ -0,0 +1,138 @@ +module Cron (parse, toProse) where + +import Common (asOrdinal, leftPad, listToProse, showDayOfWeek, showMonth, (?:)) +import qualified Cron.Expr as E +import qualified Cron.Schedule as S +import Data.List.NonEmpty (NonEmpty ((:|))) +import Intro + +parse :: String -> Either String S.Schedule +parse s = case words s of + [mn, h, dom, m, dow] -> S.fromParts mn h dom m dow + xs -> + Left + $ "Invalid cron " + ++ s + ++ ": not enough qualifiers, expecting 5 but only got " + ++ (show . length) xs + +toProse :: S.Schedule -> String +toProse s = + mconcat + [ proseTime s.minute s.hour + , ", " + , proseDate s.dayOfMonth s.month s.dayOfWeek + ] + +proseDate :: E.Expr -> E.Expr -> E.Expr -> String +proseDate dom mt dow = case (dom, mt, dow) of + (E.Every, E.Every, E.Every) -> "daily" + (E.Every, _, E.Every) -> "daily " ++ proseMonth mt + (E.Every, E.Every, E.Multi ns) -> "every " ++ listToProse (dayOfWeek <$> ns) + (E.Every, E.Every, E.Range _ _) -> proseDayOfWeek dow + (E.Every, _, E.Multi ns) -> "every " ++ listToProse (dayOfWeek <$> ns) ++ " " ++ proseMonth mt + (_, _, _) -> mconcat [proseDayOfMonth dom, " ", proseMonth mt, " ", proseDayOfWeek dow] + where + dayOfWeek m = showDayOfWeek m ?: "?" + +proseDayOfWeek :: E.Expr -> String +proseDayOfWeek = \case + E.Every -> "" + E.Multi ns -> "on " ++ listToProse (dayOfWeek <$> ns) + E.Range n m -> mconcat ["from ", dayOfWeek n, " to ", dayOfWeek m] + E.Step E.StepLEvery 1 -> "" + E.Step E.StepLEvery n -> mconcat ["every ", show n, " days of the week"] + E.Step (E.StepLRange n m) j -> + mconcat + [ "every " + , show j + , " days of the week from " + , dayOfWeek n + , " to " + , dayOfWeek m + ] + where + dayOfWeek m = showDayOfWeek m ?: "?" + +proseMonth :: E.Expr -> String +proseMonth = \case + E.Every -> "of every month" + E.Multi ns -> "of " ++ listToProse (month <$> ns) + E.Range n m -> mconcat ["from ", month n, " to ", month m] + E.Step E.StepLEvery 1 -> "of every month" + E.Step E.StepLEvery n -> mconcat ["of every ", show n, " months"] + E.Step (E.StepLRange n m) j -> + mconcat + [ "of every " + , show j + , " months from " + , month n + , " to " + , month m + ] + where + month m = showMonth m ?: "?" + +proseDayOfMonth :: E.Expr -> String +proseDayOfMonth = \case + E.Every -> "daily" + E.Multi ns -> "on the " ++ listToProse (asOrdinal <$> ns) + E.Range n m -> mconcat ["daily from the ", asOrdinal n, " to the ", asOrdinal m] + E.Step E.StepLEvery 1 -> "daily" + E.Step E.StepLEvery n -> mconcat ["every ", show n, " days"] + E.Step (E.StepLRange n m) j -> + mconcat + [ "every " + , show j + , " days from the " + , asOrdinal n + , " to the " + , asOrdinal m + ] + +proseTime :: E.Expr -> E.Expr -> String +proseTime mn h = case (mn, h) of + (E.Multi (0 :| []), E.Every) -> "At the top of every hour" + (E.Multi (0 :| []), E.Step E.StepLEvery 1) -> "At the top of every hour" + (E.Multi (n :| []), E.Multi (m :| [])) -> mconcat ["At ", leftPad 2 '0' $ show m, ":", leftPad 2 '0' $ show n] + (E.Multi (0 :| []), E.Multi ns) -> mconcat ["At the top of the ", listToProse (asOrdinal <$> ns), " hours"] + (_, E.Every) -> mconcat [proseMinute mn, " of every hour"] + (_, E.Step E.StepLEvery 1) -> mconcat [proseMinute mn, " of every hour"] + (_, _) -> mconcat [proseMinute mn, " ", proseHour h] + +proseHour :: E.Expr -> String +proseHour = \case + E.Every -> "every hour" + E.Multi (n :| []) -> mconcat ["at hour ", leftPad 2 '0' $ show n] + E.Multi ns -> "at hours " ++ listToProse (show <$> ns) + E.Range n m -> mconcat ["every hour from ", leftPad 2 '0' $ show n, " to ", leftPad 2 '0' $ show m] + E.Step E.StepLEvery 1 -> "every hour" + E.Step E.StepLEvery n -> mconcat ["every ", show n, " hours"] + E.Step (E.StepLRange n m) j -> + mconcat + [ "every " + , show j + , " hours from " + , show n + , " to " + , show m + ] + +proseMinute :: E.Expr -> String +proseMinute = \case + E.Every -> "Every minute" + E.Multi (n :| []) -> mconcat ["At minute ", leftPad 2 '0' $ show n] + E.Multi ns -> "At minutes " ++ listToProse (show <$> ns) + E.Range n m -> mconcat ["Every minute from ", leftPad 2 '0' $ show n, " to ", leftPad 2 '0' $ show m] + E.Step E.StepLEvery 1 -> "Every minute" + E.Step E.StepLEvery n -> mconcat ["every ", show n, " minutes"] + E.Step (E.StepLRange n m) j -> + mconcat + [ "every " + , show j + , " minutes from the " + , asOrdinal n + , " minute to the " + , asOrdinal m + , " minute" + ] diff --git a/src/Cron/Expr.hs b/src/Cron/Expr.hs new file mode 100644 index 0000000..a6cb4ca --- /dev/null +++ b/src/Cron/Expr.hs @@ -0,0 +1,21 @@ +module Cron.Expr (Expr (..), StepLExpr (..), showExpr) where + +import Data.List.NonEmpty (NonEmpty, intersperse) +import Data.Semigroup (sconcat) +import Intro + +data Expr = Every | Multi (NonEmpty Int) | Range Int Int | Step StepLExpr Int deriving (Show) + +data StepLExpr = StepLEvery | StepLRange Int Int deriving (Show) + +showExpr :: Expr -> String +showExpr = \case + Every -> "*" + Multi ns -> sconcat $ intersperse "," (fmap show ns) + Range n m -> mconcat [show n, "-", show m] + Step n m -> mconcat [showStepLExpr n, "/", show m] + +showStepLExpr :: StepLExpr -> String +showStepLExpr = \case + StepLEvery -> "*" + StepLRange n m -> mconcat [show n, "-", show m] diff --git a/src/Cron/Parser.hs b/src/Cron/Parser.hs new file mode 100644 index 0000000..304a1e3 --- /dev/null +++ b/src/Cron/Parser.hs @@ -0,0 +1,88 @@ +module Cron.Parser (parse) where + +import Common (fromDigits) +import Control.Applicative (Alternative, empty, liftA2, many, some, (*>), (<$), (<|>)) +import Control.Arrow (first, (>>>)) +import qualified Cron.Expr as E +import Data.List.NonEmpty (NonEmpty ((:|))) +import Intro +import Text.Read (readMaybe) + +type Token = Char + +newtype Parser a = Parser {runParser :: [Token] -> Maybe (a, [Token])} + +instance Functor Parser where + fmap f (Parser p) = Parser (p >>> fmap (first f)) + +instance Applicative Parser where + pure a = Parser (\input -> Just (a, input)) + Parser pF <*> Parser pA = Parser $ \input -> do + (f, rest) <- pF input + (a, s) <- pA rest + pure (f a, s) + +instance Alternative Parser where + empty = Parser (const Nothing) + Parser pA <|> Parser pB = Parser $ \input -> case (pA input, pB input) of + (Nothing, expr) -> expr + (expr, _) -> expr + +match :: (Token -> Bool) -> Parser Token +match p = Parser $ \case + t : ts | p t -> Just (t, ts) + _ -> Nothing + +token :: Token -> Parser Token +token = (==) >>> match + +read :: (Token -> Maybe a) -> Parser a +read f = Parser $ \case + t : ts -> case f t of + Just x -> Just (x, ts) + _ -> Nothing + _ -> Nothing + +sepBy1 :: Parser a -> Parser b -> Parser (NonEmpty a) +sepBy1 p s = liftA2 (:|) p (many (s *> p)) + +pair :: Parser a -> Parser b -> Parser c -> Parser (a, b) +pair p1 p2 s = liftA2 (,) p1 (s *> p2) + +digit :: Parser Int +digit = read $ \case + x | x `elem` ['0' .. '9'] -> readMaybe [x] :: Maybe Int + _ -> Nothing + +number :: Parser Int +number = fromDigits <$> some digit + +-- +-- Cron Exprs +-- + +cRange :: Parser E.Expr +cRange = uncurry E.Range <$> pair number number (token '-') + +cStepL :: Parser E.StepLExpr +cStepL = + (E.StepLEvery <$ token '*') + <|> (uncurry E.StepLRange <$> pair number number (token '-')) + +cStep :: Parser E.Expr +cStep = uncurry E.Step <$> pair cStepL number (token '/') + +cMulti :: Parser E.Expr +cMulti = E.Multi <$> sepBy1 number (token ',') + +cEvery :: Parser E.Expr +cEvery = E.Every <$ token '*' + +cExpr :: Parser E.Expr +cExpr = cStep <|> cEvery <|> cRange <|> cMulti + +parse :: [Token] -> Either String E.Expr +parse xs = case runParser cExpr xs of + Nothing -> Left "Invalid cron expression" + Just (expr, []) -> Right expr + Just (_, rest) -> Left ("Invalid cron expression. Couldn't parse `" ++ rest ++ "`") diff --git a/src/Cron/Schedule.hs b/src/Cron/Schedule.hs new file mode 100644 index 0000000..2ea56ab --- /dev/null +++ b/src/Cron/Schedule.hs @@ -0,0 +1,72 @@ +module Cron.Schedule (Schedule (..), fromParts) where + +import Common ((?)) +import qualified Cron.Expr as E +import qualified Cron.Parser as P +import Intro + +data Schedule = Schedule + { minute :: E.Expr + , hour :: E.Expr + , dayOfMonth :: E.Expr + , month :: E.Expr + , dayOfWeek :: E.Expr + } + deriving (Show) + +fromParts :: String -> String -> String -> String -> String -> Either String Schedule +fromParts mn h d m wd = + Schedule + <$> parseMinute mn + <*> parseHour h + <*> parseDayOfMonth d + <*> parseMonth m + <*> parseDayOfWeek wd + +parseMinute :: String -> Either String E.Expr +parseMinute s = P.parse s >>= validateMinute + +parseHour :: String -> Either String E.Expr +parseHour s = P.parse s >>= validateHour + +parseDayOfMonth :: String -> Either String E.Expr +parseDayOfMonth s = P.parse s >>= validateDayOfMonth + +parseMonth :: String -> Either String E.Expr +parseMonth s = P.parse s >>= validateMonth + +parseDayOfWeek :: String -> Either String E.Expr +parseDayOfWeek s = P.parse s >>= validateDayOfWeek + +validateMinute :: E.Expr -> Either String E.Expr +validateMinute expr = validateExpr expr >>= flip validateInRange [0 .. 59] + +validateHour :: E.Expr -> Either String E.Expr +validateHour expr = validateExpr expr >>= flip validateInRange [0 .. 23] + +validateDayOfMonth :: E.Expr -> Either String E.Expr +validateDayOfMonth expr = validateExpr expr >>= flip validateInRange [1 .. 31] + +validateMonth :: E.Expr -> Either String E.Expr +validateMonth expr = validateExpr expr >>= flip validateInRange [1 .. 12] + +validateDayOfWeek :: E.Expr -> Either String E.Expr +validateDayOfWeek expr = validateExpr expr >>= flip validateInRange [0 .. 6] + +validateExpr :: E.Expr -> Either String E.Expr +validateExpr expr = validate expr $ \case + E.Range n m -> n < m + _ -> True + +validateInRange :: E.Expr -> [Int] -> Either String E.Expr +validateInRange expr range = validate expr $ \case + E.Multi ns -> all inRange ns + E.Range n m -> inRange n && inRange m + E.Step _ _ -> True + E.Every -> True + where + inRange :: Int -> Bool + inRange = flip elem range + +validate :: E.Expr -> (E.Expr -> Bool) -> Either String E.Expr +validate expr p = p expr ? Right expr $ Left ("Invalid cron expression " ++ E.showExpr expr) diff --git a/src/Intro.hs b/src/Intro.hs new file mode 100644 index 0000000..b6c76b7 --- /dev/null +++ b/src/Intro.hs @@ -0,0 +1,64 @@ +module Intro + ( ($) + , (&&) + , (*) + , (+) + , (++) + , (-) + , (.) + , (/=) + , (<$>) + , (<*>) + , (<) + , (=<<) + , (==) + , (>>=) + , (||) + , Applicative + , Bool (False, True) + , Char + , Eq + , IO + , Int + , Maybe (Just, Nothing) + , Either (Left, Right) + , Functor + , Show + , String + , all + , break + , concat + , const + , curry + , dropWhile + , either + , elem + , filter + , flip + , foldl + , foldr + , fst + , head + , init + , last + , length + , fmap + , id + , mconcat + , mod + , not + , otherwise + , pure + , putStrLn + , reverse + , show + , snd + , uncurry + , words + , zip + , zipWith + , null + ) +where + +import Prelude diff --git a/uncron.cabal b/uncron.cabal new file mode 100644 index 0000000..cbeec89 --- /dev/null +++ b/uncron.cabal @@ -0,0 +1,65 @@ +cabal-version: 3.0 +name: uncron +version: 0.1.0.0 +license: MPL-2.0 +license-file: COPYING +author: evuez +maintainer: julien@mulga.net +build-type: Simple + +common warnings + ghc-options: + -Wall + -- -Werror + -- -Wall-missed-specialisations + -Wcpp-undef + -Widentities + -Wimplicit-prelude + -Wincomplete-record-updates + -Wincomplete-uni-patterns + -Wmissed-specialisations + -- -Wmissing-deriving-strategies + -Wmissing-export-lists + -Wmissing-exported-signatures + -Wmissing-home-modules + -- -Wmissing-import-lists + -Wmissing-local-signatures + -Wmonomorphism-restriction + -Wpartial-fields + -Wredundant-constraints + -Wunused-packages + -Wunused-type-patterns + +common exe + default-extensions: + NoImplicitPrelude + DuplicateRecordFields + OverloadedRecordDot + LambdaCase + other-modules: + Intro + Common + Cron + Cron.Expr + Cron.Schedule + Cron.Parser + build-depends: base >=4.17.2.1 + hs-source-dirs: app,src + default-language: Haskell2010 + +executable uncron + import: warnings + import: exe + main-is: Main.hs + ghc-options: + -fno-expose-internal-symbols + -O2 + +executable uncron-dyn + import: warnings + import: exe + main-is: Main.hs + ghc-options: + -fno-expose-internal-symbols + -O2 + -dynamic |