Codebase server default ui path is relative to the executable now

To test, I added a script that downloads the latest UI release and puts it next to the executable.

dev-ui-install.sh

@@ -0,0 +1,10 @@
+echo "This script downloads the latest codebase UI release"
+echo "and puts it in the correct spot next to the unison"
+echo "executable built by stack."
+echo ""
+
+stack build
+curl -L https://github.com/unisonweb/codebase-ui/releases/download/latest/ucm.zip --output ucm.zip
+parent_dir="$(dirname -- $(stack exec which unison))"
+mkdir -p "$parent_dir/ui"
+unzip -o ucm.zip -d "$parent_dir/ui"

development.markdown

@@ -8,9 +8,13 @@ _Disclaimer_ If you have trouble getting started, please get in touch via [Slack
 
 To get cracking with Unison:
 
-* [Install `stack`](https://docs.haskellstack.org/en/stable/README/#how-to-install).
-* Build the project with `stack build`. This builds all executables.
-* After building, `stack exec unison` will fire up the codebase editor, create a codebase in the current directory, and watch for `.u` file changes.  If you want to run it in a different directory, just add `unison` to your `PATH`, after finding it with `find .stack-work -name unison -type f`.  (For me, this finds two, they both work, but have different contents.  ¯\\\_(ツ)\_/¯ )
+1. [Install `stack`](https://docs.haskellstack.org/en/stable/README/#how-to-install).
+2. Build the project with `stack build`. This builds all executables.
+3. (Optional) Run `./dev-ui-install.hs` to fetch the latest release of the codebase UI. If you don't care about running the codebase UI locally you can ignore this step.
+4. After building do `stack exec unison -- init` will initialize a codebase in your home directory (in `~/.unison`). This only needs to be done once.
+5. `stack exec unison` starts Unison and watches for `.u` file changes in the current directory. If you want to run it in a different directory, just add `unison` to your `PATH`, after finding it with `stack exec which unison`.
+
+On startup, Unison prints a url for the codebase UI. If you did step 3 above, then visiting that URL in a browser will give you a nice interface to your codebase.
 
 ## Running Tests
 

parser-typechecker/src/Unison/Server/CodebaseServer.hs

@@ -87,9 +87,10 @@ import Servant.Server
     err404,
   )
 import Servant.Server.StaticFiles (serveDirectoryWebApp)
-import System.Directory (doesFileExist)
-import System.Environment (getArgs, lookupEnv)
-import System.FilePath.Posix ((</>))
+import System.Directory (doesFileExist, canonicalizePath)
+import System.Environment (getArgs, lookupEnv, getExecutablePath)
+import System.FilePath ((</>))
+import qualified System.FilePath as FilePath
 import System.Random.Stateful (getStdGen, newAtomicGenM, uniformByteStringM)
 import Text.Read (readMaybe)
 import Unison.Codebase (Codebase)
@@ -165,7 +166,7 @@ serverAPI = Proxy
 app
   :: Var v
   => Codebase IO v Ann
-  -> Maybe FilePath
+  -> FilePath
   -> Strict.ByteString
   -> Application
 app codebase uiPath expectedToken =
@@ -263,7 +264,10 @@ startServer
   -> Maybe Port
   -> Maybe String
   -> IO ()
-startServer codebase k envToken envHost envPort envUI = do
+startServer codebase k envToken envHost envPort envUI0 = do
+  -- the `canonicalizePath` resolves symlinks
+  exePath <- canonicalizePath =<< getExecutablePath
+  envUI <- canonicalizePath $ fromMaybe (FilePath.takeDirectory exePath </> "ui") envUI0
   token <- case envToken of
     Just t -> return $ C8.pack t
     _      -> genToken
@@ -301,19 +305,17 @@ serveIndex path = do
       <> " environment variable to the directory where the UI is installed."
     }
 
-serveUI :: Handler () -> Maybe FilePath -> Server WebUI
-serveUI tryAuth p _ =
-  let path = fromMaybe "ui" p
-  in  tryAuth *> serveIndex path
+serveUI :: Handler () -> FilePath -> Server WebUI
+serveUI tryAuth path _ = tryAuth *> serveIndex path
 
 server
   :: Var v
   => Codebase IO v Ann
-  -> Maybe FilePath
+  -> FilePath
   -> Strict.ByteString
   -> Server AuthedServerAPI
 server codebase uiPath token =
-  serveDirectoryWebApp (fromMaybe "ui" uiPath </> "static")
+  serveDirectoryWebApp (uiPath </> "static")
     :<|> ((\t ->
             serveUI (tryAuth t) uiPath
               :<|> (    (    (serveNamespace (tryAuth t) codebase)