Let projects configure their artifacts pull/push options

With this commit, we first look at the artifacts options in the project
configuration, then fall back on the user configuration if necessary.

Relates to #87

4 files changed, 36 insertions, 5 deletions

diff --git a/buildstream/_artifactcache/artifactcache.py b/buildstream/_artifactcache/artifactcache.py
index 1f643ca45..41625b655 100644
--- a/buildstream/_artifactcache/artifactcache.py
+++ b/buildstream/_artifactcache/artifactcache.py
@@ -52,9 +52,10 @@ def buildref(element, key):
 #
 # Args:
 #     context (Context): The BuildStream context
+#     project (Project): The BuildStream project
 #
 class ArtifactCache():
-    def __init__(self, context):
+    def __init__(self, context, project):
 
         self.context = context
 
@@ -66,9 +67,15 @@ class ArtifactCache():
         self.__pull_local = False
         self.__push_local = False
 
-        self.artifact_pull = context.artifact_pull
-        self.artifact_push = context.artifact_push
-        self.artifact_push_port = context.artifact_push_port
+        if any((project.artifact_pull, project.artifact_push)):
+            self.artifact_pull = project.artifact_pull
+            self.artifact_push = project.artifact_push
+            self.artifact_push_port = project.artifact_push_port
+
+        else:
+            self.artifact_pull = context.artifact_pull
+            self.artifact_push = context.artifact_push
+            self.artifact_push_port = context.artifact_push_port
 
         if self.artifact_push:
             if self.artifact_push.startswith("/") or \
diff --git a/buildstream/_pipeline.py b/buildstream/_pipeline.py
index 6359f1012..07f72bdc9 100644
--- a/buildstream/_pipeline.py
+++ b/buildstream/_pipeline.py
@@ -133,7 +133,7 @@ class Pipeline():
                  cache_ticker=None):
         self.context = context
         self.project = project
-        self.artifacts = ArtifactCache(self.context)
+        self.artifacts = ArtifactCache(self.context, self.project)
         self.session_elements = 0
         self.total_elements = 0
         self.unused_workspaces = []
diff --git a/buildstream/data/projectconfig.yaml b/buildstream/data/projectconfig.yaml
index aa9605358..6406f1609 100644
--- a/buildstream/data/projectconfig.yaml
+++ b/buildstream/data/projectconfig.yaml
@@ -229,6 +229,22 @@ split-rules:
   - |
     %{datadir}/zoneinfo/**
 
+#
+#    Artifacts
+#
+artifacts:
+
+  # A url from which to download prebuilt artifacts
+  pull-url: ''
+
+  # A url to upload built artifacts to
+  # (must point to the same repository as pull-url)
+  push-url: ''
+
+  # Specify the port number for pushing artifacts, if it's
+  # not the default port 22
+  push-port: 22
+
 # Element Overrides
 #
 # Base attributes declared by element default yaml files
diff --git a/buildstream/project.py b/buildstream/project.py
index a1e111e52..f44ca4605 100644
--- a/buildstream/project.py
+++ b/buildstream/project.py
@@ -165,6 +165,7 @@ class Project():
             'split-rules', 'elements', 'plugins',
             'aliases', 'name',
             'arches', 'host-arches',
+            'artifacts',
         ])
 
         # Resolve arches keyword, project may have arch conditionals
@@ -195,6 +196,13 @@ class Project():
         # Workspace configurations
         self.__workspaces = self._load_workspace_config()
 
+        # Load artifacts pull/push configuration for this project
+        artifacts = _yaml.node_get(config, Mapping, 'artifacts')
+        _yaml.validate_node(artifacts, ['pull-url', 'push-url', 'push-port'])
+        self.artifact_pull = _yaml.node_get(artifacts, str, 'pull-url', default_value='') or None
+        self.artifact_push = _yaml.node_get(artifacts, str, 'push-url', default_value='') or None
+        self.artifact_push_port = _yaml.node_get(artifacts, int, 'push-port', default_value=22)
+
         return config
 
     # _resolve():