Allow optionally configuring git-annex with -fEKG to enable awesome remote monitoring interfaceat http://localhost:4242/

7 files changed, 48 insertions, 2 deletions

diff --git a/BuildFlags.hs b/BuildFlags.hs
index 40d5bb29b..1dba47eaf 100644
--- a/BuildFlags.hs
+++ b/BuildFlags.hs
@@ -60,4 +60,7 @@ buildFlags = filter (not . null)
 #ifdef WITH_CRYPTOHASH
 	, "CryptoHash"
 #endif
+#ifdef WITH_EKG
+	, "EKG"
+#endif
 	]
diff --git a/GitAnnex.hs b/GitAnnex.hs
index b73cd9416..d6de50d03 100644
--- a/GitAnnex.hs
+++ b/GitAnnex.hs
@@ -5,7 +5,7 @@
  - Licensed under the GNU GPL version 3 or higher.
  -}
 
-{-# LANGUAGE CPP #-}
+{-# LANGUAGE CPP, OverloadedStrings #-}
 
 module GitAnnex where
 
@@ -87,6 +87,9 @@ import qualified Command.XMPPGit
 import qualified Command.Test
 import qualified Command.FuzzTest
 #endif
+#ifdef WITH_EKG
+import System.Remote.Monitoring
+#endif
 
 cmds :: [Command]
 cmds = concat
@@ -169,4 +172,8 @@ header :: String
 header = "git-annex command [option ...]"
 
 run :: [String] -> IO ()
-run args = dispatch True args cmds options [] header Git.CurrentRepo.get
+run args = do
+#ifdef WITH_EKG
+	_ <- forkServer "localhost" 4242
+#endif
+	dispatch True args cmds options [] header Git.CurrentRepo.get
diff --git a/debian/changelog b/debian/changelog
index 17911cab5..b7a73d3a1 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,10 @@
+git-annex (4.20131107) UNRELEASED; urgency=low
+
+  * Allow optionally configuring git-annex with -fEKG to enable awesome
+    remote monitoring interfaceat http://localhost:4242/
+
+ -- Joey Hess <joeyh@debian.org>  Wed, 06 Nov 2013 16:14:14 -0400
+
 git-annex (4.20131106) unstable; urgency=low
 
   * Improve local pairing behavior when two computers both try to start
diff --git a/doc/ekg.mdwn b/doc/ekg.mdwn
new file mode 100644
index 000000000..3bbea8614
--- /dev/null
+++ b/doc/ekg.mdwn
@@ -0,0 +1,14 @@
+You can `cabal configure -fEKG` to build a git-annex that includes
+the EKG remote monitoring interface.
+
+To access the EKG control panel, go to
+<http://localhost:4242/> while a git-annex command is running.
+
+This EKG build is mostly useful for debugging resource usage problems.
+
+[[!img ekg.png caption="git-annex webapp startup, and assistant startup scan"]]
+
+Note that since only one process can open port 4242 at a time, running
+more than one git-annex process with EKG support at the same time can
+result in some "resource busy (Address already in use)" messages -- but
+git-annex will continue to work.
diff --git a/doc/ekg/ekg.png b/doc/ekg/ekg.png
new file mode 100644
index 000000000..a8d16a2d8
--- /dev/null
+++ b/doc/ekg/ekg.png
diff --git a/doc/install/cabal.mdwn b/doc/install/cabal.mdwn
index 4eac597f1..3270dd0f9 100644
--- a/doc/install/cabal.mdwn
+++ b/doc/install/cabal.mdwn
@@ -50,3 +50,9 @@ you want, and use cabal as follows inside its source tree:
 	cabal configure
 	cabal build
 	cabal install --bindir=$HOME/bin
+
+## EKG
+
+When building with cabal, you can optionally enable the 
+[[EKG monitoring interface|ekg]]. This is great for debugging resource
+usage problems.
diff --git a/git-annex.cabal b/git-annex.cabal
index ef0259e7a..848477c18 100644
--- a/git-annex.cabal
+++ b/git-annex.cabal
@@ -74,6 +74,10 @@ Flag Quvi
 Flag CryptoHash
   Description: Enable use of cryptohash for checksumming
 
+Flag EKG
+  Description: Enable use of EKG to monitor git-annex as it runs (at http://localhost:4242/)
+  Default: False
+
 Executable git-annex
   Main-Is: git-annex.hs
   Build-Depends: MissingH, hslogger, directory, filepath,
@@ -177,6 +181,11 @@ Executable git-annex
     Build-Depends: aeson
     CPP-Options: -DWITH_QUVI
 
+  if flag(EKG)
+    Build-Depends: ekg
+    GHC-Options: -with-rtsopts=-T
+    CPP-Options: -DWITH_EKG
+
 source-repository head
   type: git
   location: git://git-annex.branchable.com/