Report disk free status

4 files changed, 37 insertions, 3 deletions

diff --git a/ARCH b/ARCH
index fe62ce7..2a368b0 100644
--- a/ARCH
+++ b/ARCH
@@ -247,6 +247,10 @@ Requests for admins:
   filesystem Lorry Controller uses (in bytes). This information is
   included in the `/1.0/status` query as well, but this is easier to
   deal with for simple monitoring. (MON/DU)
+    - N.B.: It turns out it's not easy to return a JSON object that is
+      only an integer in bottle.py, so this helper method is skipped,
+      for now; the disk free status is added to the normal status in
+      any case
 * `POST /1.0/stop-queue` causes WEBAPP to stop scheduling new jobs to
   run. Any currently running jobs are not affected. (RT/QSTOP)
 * `POST /1.0/start-queue` causes WEBAPP to start scheduling jobs
diff --git a/lorry-controller-webapp b/lorry-controller-webapp
index 0e5fd5c..e37420b 100755
--- a/lorry-controller-webapp
+++ b/lorry-controller-webapp
@@ -39,6 +39,7 @@ STATUS_HTML_TEMPLATE = '''
     <h1>Status of Lorry Controller</h1>
 
     <p>Running queue: {running-queue}.</p>
+    <p>Free disk space: {disk-free-gib} GiB.</p>
 
     <hr>
 
@@ -113,7 +114,7 @@ class StatusRenderer(object):
 
     '''Helper class for rendering service status as JSON/HTML'''
 
-    def get_status_as_dict(self, statedb):
+    def get_status_as_dict(self, statedb, work_directory):
         quotes = [
             "Never get drunk unless you're willing to pay for it - "
             "the next day.",
@@ -125,6 +126,7 @@ class StatusRenderer(object):
             'running-queue': statedb.get_running_queue(),
             'timestamp': time.strftime('%Y-%m-%d %H:%M:%S'),
             }
+        status.update(self.get_free_disk_space(work_directory))
         return status
 
     def render_status_as_html(self, status):
@@ -135,6 +137,15 @@ class StatusRenderer(object):
         with open(filename, 'w') as f:
             f.write(html)
 
+    def get_free_disk_space(self, dirname):
+        result = os.statvfs(dirname)
+        free_bytes = result.f_bavail * result.f_bsize
+        return {
+            'disk-free': free_bytes,
+            'disk-free-mib': free_bytes / 1024**2,
+            'disk-free-gib': free_bytes / 1024**2,
+            }
+
 
 class Status(LorryControllerRoute):
 
@@ -143,7 +154,7 @@ class Status(LorryControllerRoute):
 
     def run(self, **kwargs):
         renderer = StatusRenderer()
-        status = renderer.get_status_as_dict(self.statedb)
+        status = renderer.get_status_as_dict(self.statedb, self.app_settings['statedb'])
         renderer.write_status_as_html(status, self.app_settings['status-html'])
         return status
 
@@ -155,7 +166,7 @@ class StatusHTML(LorryControllerRoute):
 
     def run(self, **kwargs):
         renderer = StatusRenderer()
-        status = renderer.get_status_as_dict(self.statedb)
+        status = renderer.get_status_as_dict(self.statedb, self.app_settings['statedb'])
         renderer.write_status_as_html(status, self.app_settings['status-html'])
         return renderer.render_status_as_html(status)
 
diff --git a/yarns.webapp/020-status.yarn b/yarns.webapp/020-status.yarn
index ae5a779..0a704e8 100644
--- a/yarns.webapp/020-status.yarn
+++ b/yarns.webapp/020-status.yarn
@@ -10,6 +10,9 @@ it has no Lorry or Trove specs.
     WHEN admin makes request GET /1.0/status
     THEN response is application/json
     AND response has running-queue set to false
+    AND response has disk-free set
+    AND response has disk-free-mib set
+    AND response has disk-free-gib set
     AND static status page got updated
     FINALLY WEBAPP terminates
 
diff --git a/yarns.webapp/900-implementations.yarn b/yarns.webapp/900-implementations.yarn
index 0e3aa9e..01c6fbe 100644
--- a/yarns.webapp/900-implementations.yarn
+++ b/yarns.webapp/900-implementations.yarn
@@ -122,6 +122,22 @@ value is expresssed as a JSON value in the step.
         sys.exit(1)
     ' < "$DATADIR/response.body"
 
+In some cases, such as free disk space, we don't care about the actual
+value, but we do care that it is there.
+
+    IMPLEMENTS THEN response has (\S+) set
+    cat "$DATADIR/response.body"
+    python -c '
+    import json, os, sys
+    data = json.load(sys.stdin)
+    key = os.environ["MATCH_1"]
+    if key not in data:
+        sys.stderr.write(
+            "Key {key} is not set, but was expected to be set".format (
+                key=key))
+        sys.exit(1)
+    ' < "$DATADIR/response.body"
+
 
 Status web page
 ---------------