# HG changeset patch
# User Ludovic Chabant <ludovic@chabant.com>
# Date 1517018702 28800
# Node ID 971b4d67e82ab9e92ab818404f17be25aa3b3e90
# Parent  e0796761cdcc568720d3bcbdd5db0bfdeba0cd2e
serve: Fix problems with assets disappearing between servings.

When an asset file changes, its source's pipeline is re-run. But that created
a bake record that only had that pipeline's output, so the other outputs were
incorrectly considered empty and therefore any stray files were removed. Now we
copy over bake records for the pipelines we don't run.

diff -r e0796761cdcc -r 971b4d67e82a piecrust/baking/baker.py
--- a/piecrust/baking/baker.py	Fri Jan 26 18:02:07 2018 -0800
+++ b/piecrust/baking/baker.py	Fri Jan 26 18:05:02 2018 -0800
@@ -31,7 +31,8 @@
                  allowed_pipelines=None,
                  forbidden_pipelines=None,
                  allowed_sources=None,
-                 rotate_bake_records=True):
+                 rotate_bake_records=True,
+                 keep_unused_records=False):
         self.appfactory = appfactory
         self.app = app
         self.out_dir = out_dir
@@ -40,6 +41,7 @@
         self.forbidden_pipelines = forbidden_pipelines
         self.allowed_sources = allowed_sources
         self.rotate_bake_records = rotate_bake_records
+        self.keep_unused_records = keep_unused_records
 
     def bake(self):
         start_time = time.perf_counter()
@@ -108,7 +110,7 @@
         # Handle deletions, collapse records, etc.
         ppmngr.postJobRun()
         ppmngr.deleteStaleOutputs()
-        ppmngr.collapseRecords()
+        ppmngr.collapseRecords(self.keep_unused_records)
 
         # All done with the workers. Close the pool and get reports.
         pool_stats = pool.close()
diff -r e0796761cdcc -r 971b4d67e82a piecrust/pipelines/base.py
--- a/piecrust/pipelines/base.py	Fri Jan 26 18:02:07 2018 -0800
+++ b/piecrust/pipelines/base.py	Fri Jan 26 18:05:02 2018 -0800
@@ -283,10 +283,22 @@
                         pass
                     logger.info('[delete] %s' % path)
 
-    def collapseRecords(self):
+    def collapseRecords(self, keep_unused_records=False):
+        seen_records = []
         for ppinfo in self.getPipelineInfos():
             ctx = PipelineCollapseRecordContext(ppinfo.record_history)
             ppinfo.pipeline.collapseRecords(ctx)
+            seen_records.append(ppinfo.pipeline.record_name)
+
+        if keep_unused_records:
+            cur_recs = self.record_histories.current
+            prev_recs = self.record_histories.previous
+            for prev_rec in prev_recs.records:
+                if prev_rec.name in seen_records:
+                    continue
+
+                logger.debug("Keeping record: %s" % prev_rec.name)
+                cur_recs.records.append(prev_rec)
 
     def shutdownPipelines(self):
         for ppinfo in self.getPipelineInfos():
diff -r e0796761cdcc -r 971b4d67e82a piecrust/serving/procloop.py
--- a/piecrust/serving/procloop.py	Fri Jan 26 18:02:07 2018 -0800
+++ b/piecrust/serving/procloop.py	Fri Jan 26 18:05:02 2018 -0800
@@ -152,7 +152,8 @@
             self.appfactory, self._app, self.out_dir,
             allowed_pipelines=['asset'],
             allowed_sources=allowed_sources,
-            rotate_bake_records=False)
+            rotate_bake_records=False,
+            keep_unused_records=(allowed_sources is not None))
         records = baker.bake()
 
         self._onPipelinesRun(records)