Make Google API keys available for the Java codebase

build/config/android/rules.gni

Index: build/config/android/rules.gni
diff --git a/build/config/android/rules.gni b/build/config/android/rules.gni
index 76f57dd73758fced358cfcbdb9ca90f6d11362fb..60d0fff1b70b0dc3ab990400757706f8b759a596 100644
--- a/build/config/android/rules.gni
+++ b/build/config/android/rules.gni
@@ -397,6 +397,63 @@ template("java_cpp_enum") {
   }
 }
 
+# Declare a target for generating Java constants from Google API Keys.
+#
+# This target will create a single .srcjar. Adding this target to an
+# android_library target's srcjar_deps will make the generated java files be
+# included in that library's final outputs.
+#
+# Example
+#   java_google_api_keys("foo_generated_keys") {
+#   }
+template("java_google_api_keys") {

[agrieve, 2015/10/30 00:55:13]

This is not really a general-purpose template (given that it takes no
parameters), so it should either be defined in the file that uses it, or just
skip defining it as a template and add in the two rules (action+zip) directly.

[dvh, 2015/10/30 20:56:21]

Are there examples of non-general-purpose things I could use to create my rule?

[agrieve, 2015/10/31 02:09:37]

What I think would be best is to avoid declaring a template() altogether, and
just declare an action() and zip() within chrome/android/BUILD.gn

[brettw, 2015/11/02 05:29:18]

+1

+  set_sources_assignment_filter([])

[agrieve, 2015/10/30 00:55:14]

No need to do this since the template doesn't look for a sources parameter

[dvh, 2015/10/30 20:56:21]

Done.

+  forward_variables_from(invoker, [ "testonly" ])
+
+  generate_google_api_keys_target_name =

[agrieve, 2015/10/30 00:55:13]

nit: It has become customary to prefix all local variables with _ (that is,
those that are not used as parameters to rules)

[dvh, 2015/10/30 20:56:21]

Done.

+      "${target_name}__generate_google_api_keys"
+  zip_srcjar_target_name = "${target_name}__zip_srcjar"
+  final_target_name = target_name
+
+  action(generate_google_api_keys_target_name) {
+    visibility = [ ":$zip_srcjar_target_name" ]
+
+    # The sources aren't compiled so don't check their dependencies.
+    check_includes = false

[agrieve, 2015/10/30 00:55:13]

this isn't applicable since there are no sources

[dvh, 2015/10/30 20:56:21]

Done.

+
+    script = "//build/android/gyp/java_google_api_keys.py"
+    gen_dir = "${target_gen_dir}/${target_name}/java_google_api_keys"
+    outputs = [
+      get_path_info(rebase_path("GoogleAPIKeys.java", ".", gen_dir), "abspath"),

[agrieve, 2015/10/30 00:55:13]

Nit: I think rebase_path(foo, "", bar) will return an abspath, so you could use
that and remove get_path_info()

[dvh, 2015/10/30 20:56:21]

Done.

+    ]
+
+    args = [ rebase_path(gen_dir, root_build_dir) ]
+  }
+
+  generate_google_api_keys_outputs =

[agrieve, 2015/10/30 00:55:14]

nit: this is used only within zip(), so put it within zip()

[dvh, 2015/10/30 20:56:21]

Done.

+      get_target_outputs(":$generate_google_api_keys_target_name")
+  base_gen_dir =

[agrieve, 2015/10/30 00:55:14]

I believe this is equivalent to:
base_gen_dir = target_gen_dir

[dvh, 2015/10/30 20:56:21]

Could you tell me more about that?
I'm not even sure to understand what get_label_info() does eventually.
Is there some doc I could read?

[agrieve, 2015/10/31 02:09:37]

The command "gn help" has pretty exhaustive docs.

Try doing:
  print(target_gen_dir)

both inside of that action() and outside of the action(), and I think they'll
print the same value

+      get_label_info(":$generate_google_api_keys_target_name", "target_gen_dir")
+
+  srcjar_path = "${target_gen_dir}/${target_name}.srcjar"
+  zip(zip_srcjar_target_name) {
+    visibility = [ ":$final_target_name" ]
+    inputs = generate_google_api_keys_outputs
+    output = srcjar_path
+    base_dir = base_gen_dir
+    deps = [
+      ":$generate_google_api_keys_target_name",
+    ]
+  }
+
+  group(final_target_name) {
+    forward_variables_from(invoker, [ "visibility" ])
+    public_deps = [
+      ":$zip_srcjar_target_name",
+    ]
+  }
+}
+
 # Declare a target for processing a Jinja template.
 #
 # Variables