doc: Build the docs without Buildstream installed

.gitlab-ci.yml

@@ -143,7 +143,6 @@ docs:
   - pip3 install sphinx-click
   - pip3 install sphinx_rtd_theme
   - cd dist && ./unpack.sh && cd buildstream
-  - pip3 install .
   - make BST_FORCE_SESSION_REBUILD=1 -C doc
   - cd ../..
   - mv dist/buildstream/doc/build/html public

doc/Makefile

@@ -31,6 +31,9 @@ ifneq ($(strip $(BST_FORCE_SESSION_REBUILD)),)
 BST2HTMLOPTS = --force
 endif
 
+# Help Python find buildstream and its plugins
+PYTHONPATH=$(CURDIR)/..:$(CURDIR)/../buildstream/plugins
+
 
 .PHONY: all clean templates templates-clean sessions sessions-prep sessions-clean html devhelp
 
@@ -65,7 +68,6 @@ define plugin-doc-skeleton
 endef
 
 
-# We set PYTHONPATH here because source/conf.py sys.modules hacks dont seem to help sphinx-build import the plugins
 all: html devhelp
 
 clean: templates-clean sessions-clean
@@ -103,7 +105,7 @@ sessions-prep:
 #
 sessions: sessions-prep
 	for file in $(wildcard sessions/*.run); do		\
-	    $(BST2HTML) $(BST2HTMLOPTS) --description $$file;	\
+	    PYTHONPATH=$(PYTHONPATH) $(BST2HTML) $(BST2HTMLOPTS) --description $$file;	\
 	done
 
 sessions-clean:
@@ -114,7 +116,7 @@ sessions-clean:
 #
 html devhelp: templates sessions
 	@echo "Building $@..."
-	PYTHONPATH=$(CURDIR)/../buildstream/plugins \
+	PYTHONPATH=$(PYTHONPATH) \
 	    $(SPHINXBUILD) -b $@ $(ALLSPHINXOPTS) "$(BUILDDIR)/$@" \
 	    $(wildcard source/*.rst) \
 	    $(wildcard source/tutorial/*.rst) \

doc/bst2html.py

@@ -37,6 +37,7 @@ import click
 
 from buildstream import _yaml
 from buildstream import utils
+from buildstream._frontend import cli as bst_cli
 from buildstream._exceptions import BstError
 
 
@@ -175,6 +176,19 @@ def ansi2html(text, palette='solarized'):
     return sub
 
 
+@contextmanager
+def capture_stdout_stderr():
+    from io import StringIO
+
+    oldstdout, sys.stdout = sys.stdout, StringIO()
+    oldstderr, sys.stderr = sys.stderr, StringIO()
+
+    yield sys.stdout, sys.stderr
+
+    sys.stdout = oldstdout
+    sys.stderr = oldstderr
+
+
 # workdir()
 #
 # Sets up a new temp directory with a config file
@@ -219,9 +233,11 @@ def workdir(source_cache=None):
 def run_command(config_file, directory, command):
     click.echo("Running command in directory '{}': bst {}".format(directory, command), err=True)
 
-    argv = ['bst', '--colors', '--config', config_file] + shlex.split(command)
-    p = subprocess.Popen(argv, cwd=directory, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
-    out, _ = p.communicate()
+    args = ['--colors', '--config', config_file, '--directory', directory] + shlex.split(command)
+
+    with capture_stdout_stderr() as (out, _):
+        bst_cli.main(args=args, prog_name=bst_cli.name)
+
     return out.decode('utf-8').strip()