Merge branch 'spec-from-stdin' into 'master'

Add: Allow spec to be passed in via stdin

See merge request larswirzenius/vmdb2!8

3 files changed, 15 insertions, 6 deletions

diff --git a/vmdb/app.py b/vmdb/app.py
index 4da30a9..9db656b 100644
--- a/vmdb/app.py
+++ b/vmdb/app.py
@@ -68,9 +68,14 @@ class Vmdb2(cliapp.Application):
             sys.exit(1)
 
     def load_spec_file(self, filename):
-        vmdb.progress('Load spec file {}'.format(filename))
         spec = vmdb.Spec()
-        spec.load_file(filename)
+        if filename == "-":
+            vmdb.progress('Load spec from stdin')
+            spec.load_file(sys.stdin)
+        else:
+            vmdb.progress('Load spec file {}'.format(filename))
+            with open(filename) as f:
+                spec.load_file(f)
         return spec
 
     def run_steps(self, steps, state):
diff --git a/vmdb/spec.py b/vmdb/spec.py
index 44f4e66..98f5c56 100644
--- a/vmdb/spec.py
+++ b/vmdb/spec.py
@@ -25,9 +25,8 @@ class Spec:
     def __init__(self):
         self._dict = None
 
-    def load_file(self, filename):
-        with open(filename) as f:
-            self._dict = yaml.safe_load(f)
+    def load_file(self, f):
+        self._dict = yaml.safe_load(f)
 
     def as_dict(self):
         return dict(self._dict)
diff --git a/vmdb2.mdwn b/vmdb2.mdwn
index 9822143..4573605 100644
--- a/vmdb2.mdwn
+++ b/vmdb2.mdwn
@@ -108,7 +108,12 @@ buster onto it. It also installs a kernel, and a boot loader.
 To use this, save the specification into `test.vmdb`, and run the
 following command:
 
-    sudo vmdb2 test.vmdb --output test.img --verbose
+    sudo vmdb2 --output test.img --verbose test.vmdb
+
+Alternatively the specification can be passed in via stdin by setting the
+file name to `-`, lke so:
+
+    cat test.vmdb | sudo vmdb2 --output test.img --verbose -
 
 This will take a long time, mostly at the `debootstrap` step.