Add yarn for no lorry-controller.conf

4 files changed, 79 insertions, 2 deletions

diff --git a/lorry-controller-webapp b/lorry-controller-webapp
index a8c7fdd..6a3b0e2 100755
--- a/lorry-controller-webapp
+++ b/lorry-controller-webapp
@@ -16,6 +16,7 @@
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 
 
+import errno
 import logging
 import json
 import os
@@ -206,8 +207,14 @@ class ReadConfiguration(LorryControllerRoute):
         filename = os.path.join(
             self.app_settings['configuration-directory'],
             'lorry-controller.conf')
-        with open(filename) as f:
-            return json.load(f)
+        try:
+            with open(filename) as f:
+                return json.load(f)
+        except IOError as e:
+            if e.errno == errno.ENOENT:
+                # File doesn't exist. Return an empty configuration.
+                return []
+            bottle.abort(500, 'Error reading %s: %s' % (filename, e))
 
 
 class ListQueue(LorryControllerRoute):
diff --git a/yarns.webapp/030-queue-management.yarn b/yarns.webapp/030-queue-management.yarn
index b58a63f..32ad7cd 100644
--- a/yarns.webapp/030-queue-management.yarn
+++ b/yarns.webapp/030-queue-management.yarn
@@ -33,3 +33,36 @@ new one, and verify that the `running-queue` status is still `true`.
 Finally, clean up.
 
     FINALLY WEBAPP terminates
+
+
+Read CONFGIT
+------------
+
+We need to be able to get Lorry Controller, specifically WEBAPP, to
+update its configuration and run-queue from CONFGIT using the
+`/1.0/read-configuration` HTTP API request.
+
+First, set up WEBAPP.
+
+    SCENARIO WEBAPP updates its configuration from CONFGIT
+    GIVEN a new git repository in CONFGIT
+    AND WEBAPP uses CONFGIT as its configuration directory
+    AND a running WEBAPP
+
+We'll start with an empty configuration. This is the default state
+when WEBAPP has never read its configuration.
+
+    WHEN admin makes request GET /1.0/list-queue
+    THEN response has queue set to []
+    
+Make WEBAPP read an empty configuration. Or rather, a configuration
+that does not match any existing `.lorry` files.
+
+    GIVEN an empty lorry-controller.conf in CONFGIT
+    WHEN admin makes request GET /1.0/read-configuration
+    AND admin makes request GET /1.0/list-queue
+    THEN response has queue set to []
+
+Finally, clean up.
+
+    FINALLY WEBAPP terminates
diff --git a/yarns.webapp/900-implementations.yarn b/yarns.webapp/900-implementations.yarn
index 01c6fbe..003096f 100644
--- a/yarns.webapp/900-implementations.yarn
+++ b/yarns.webapp/900-implementations.yarn
@@ -30,6 +30,7 @@ be running until it crashes or is explicitly killed.
     start-stop-daemon -S -x "$SRCDIR/lorry-controller-webapp" \
         -b -p "$DATADIR/webapp.pid" -m --verbose \
         -- \
+        --configuration-directory "$DATADIR/confgit" \
         --statedb "$DATADIR/webapp.db" \
         --status-html "$DATADIR/lc-status.html" \
         --log-level debug \
@@ -64,6 +65,30 @@ Also test that WEBAPP isn't running.
         exit 1
     fi
 
+Managing Lorry Controller configuration
+---------------------------------------
+
+We need to be able to create, and change, the `lorry-controller.conf`
+file, and other files, in CONFGIT. First of all, we need to create
+CONFGIT.
+
+    IMPLEMENTS GIVEN a new git repository in (\S+)
+    git init "$DATADIR/$MATCH_1"
+
+Then we need to create an empty `lorry-controller.conf` file there.
+This is not just an empty file, it must be a JSON file that contains
+an empty list object.
+
+    IMPLEMENTS GIVEN an empty lorry-controller.conf in (\S+)
+    printf '[]\n' > "$DATADIR/$MATCH_1/lorry-controller.conf"
+
+Further, we need to be able to tell WEBAPP, when it runs, where the
+configuration directory is.
+
+    IMPLEMENTS GIVEN WEBAPP uses (\S+) as its configuration directory
+    add_to_config_file "$DATADIR/webapp.conf" \
+        configuration-directory "$DATADIR/$MATCH_1"
+
 Making and analysing GET requests
 ---------------------------------
 
diff --git a/yarns.webapp/yarn.sh b/yarns.webapp/yarn.sh
index 58af354..a5f22b5 100644
--- a/yarns.webapp/yarn.sh
+++ b/yarns.webapp/yarn.sh
@@ -30,3 +30,15 @@ kill_daemon_using_pid_file()
         echo "Error killing daemon running as pid $pid"
     fi
 }
+
+
+# Add a configuration item to a cliapp-style configuration file.
+
+add_to_config_file()
+{
+    if [ ! -e "$1" ]
+    then
+        printf '[config]\n' > "$1"
+    fi
+    printf '%s = %s\n' "$2" "$3" >> "$1"
+}