Module documentation for 0.1.0.7

• Database
  • Database.Persist
    • Database.Persist.Discover
      • Database.Persist.Discover.Exe

persistent-discover

Supports automatic discovery of yourpersistent models.

As an executable

Let’s say you’ve got a ton ofpersistent database models, all defined in amodule hierarchy like this:

src/  Models/    Foo.hs    Bar.hs    Baz.hs    Blargh.hs    What.hs    OhNo.hs

If you’re usingpersistent to automatically generate migrations, you’ll wantto have all the[EntityDef] in scope from each module. You can do that byimporting each module that defines models and calling$(discoverEntities),introduced inpersistent-2.13.

But you may forget to import a module.

This utility importsall the modules defined in the current directory andsub-directories, and then it calls$(discoverEntities) for you.

To use it, place the following command in a file, located in the same directorythat your Haskell modules are in:

{-# OPTIONS_GHC -F -pgmF persistent-discover #-}

Let’s say we put that insrc/Models/All.hs.This generates a moduleModels.All that exports a single item:allEntities,which is a[EntityDef] and can be used bymigrateModels to properly performmigrations.

You’ll need to addpersistent-discover to thebuild-tool-depends on your cabal filefor this to work.

Changelog for persistent-discover

Unreleased changes

0.1.0.7

• Support mtl-2.3#9

0.1.0.6

• Support GHC 9.4#7

0.1.0.5

• Fix a bug whereTemplateHaskell pragma was not added.#6

0.1.0.4

• Fix a bug where non-Haskell files would be picked up and imported in thegenerated file.#4

0.1.0.3

• Remove embarrasing lib module.

0.1.0.2

• Support GHC 9#3

0.1.0.1

• Fix behavior where uppercase directories (eg on Mac OS) would cause incorrectmodule names.#2

0.1.0.0

• Initial Release