Use prepare script to setup public link-to-repo when available (open-…

…telemetry#1165)

Makefile

@@ -1,6 +1,7 @@
 HTMLTEST_DIR=tmp
 HTMLTEST?=htmltest # Specify as make arg if different
 HTMLTEST_ARGS?=--skip-external
+OTEL_GEN_REPO?=../$(shell basename $(shell pwd)).g
 
 # Use $(HTMLTEST) in PATH, if available; otherwise, we'll get a copy
 ifeq (, $(shell which $(HTMLTEST)))
@@ -19,3 +20,15 @@ clean:
 get-link-checker:
 	rm -Rf $(HTMLTEST_DIR)/bin
 	curl https://htmltest.wjdp.uk | bash -s -- -b $(HTMLTEST_DIR)/bin
+
+# For local development, create `public` as a symlink to a given git repo (if it
+# exists), for the purpose of tracking build changes:
+public:
+	@if [[ -e "$(OTEL_GEN_REPO)" ]]; then \
+		set -x && ln -s $(OTEL_GEN_REPO) public; \
+	elif [[ -z "$(CI)" ]]; then \
+		echo "WARNING: cannot link public to '$(OTEL_GEN_REPO)' since the directory doesn't exist"; \
+	fi
+
+ls-public:
+	if [[ -e public ]]; then ls -ld public; fi

package.json

@@ -11,6 +11,7 @@
     "_get:no": "echo SKIPPING get operation",
     "_get:submodule": "set -x && git submodule update --init ${DEPTH:- --depth 1}",
     "_get:submodule:non-lang": "npm run _get:submodule -- content-modules/opentelemetry-specification themes/docsy",
+    "_mkdir:public": "make public ls-public",
     "_prebuild": "run-s get:submodule cp:spec",
     "_prepare:docsy": "cd themes/docsy && npm install",
     "_serve:hugo": "hugo serve -DFE --minify",
@@ -31,7 +32,7 @@
     "prebuild": "npm run _prebuild",
     "precheck-links:all": "npm run build",
     "precheck-links": "npm run build",
-    "prepare": "run-s get:submodule _prepare:docsy",
+    "prepare": "run-s get:submodule _prepare:docsy _mkdir:public",
     "preserve:hugo": "npm run _prebuild",
     "preserve": "npm run _prebuild",
     "s": "run-s",