Dunfell, nodejs and typescript - short experience report

Simon Vogl

I have some remarks and questions about the npm/nodejs support in dunfell that I wanted to share. We are creating nodejs-based IoT edge solutions and upgrading our build environments to Dunfell one by one. In the course of this, we are switching to the new npm-implementation and found a few small issues.

Firstly, the do_configure() task takes quite some time to complete. After a quick analysis, I saw that most of the time is being spent in creating the npmrc files while packing the dependent packages. I wrote a small workaround to directly create the file instead of calling 'npm config', which results in a 3x-4x speedup:

Signed-off-by: Simon Vogl <simon@...>
 lib/bb/fetch2/npm.py | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/lib/bb/fetch2/npm.py b/lib/bb/fetch2/npm.py
index 4789850..2720d87 100644
--- a/lib/bb/fetch2/npm.py
+++ b/lib/bb/fetch2/npm.py
@@ -97,13 +97,18 @@ class NpmEnvironment(object):
                 cmd = "NPM_CONFIG_GLOBALCONFIG=%s " % cfgfile + cmd
                 return runfetchcmd(cmd, d, workdir=workdir)
+            cfg = open(cfgfile, "a")
             if self.configs:
                 for key, value in self.configs:
-                    _run("npm config set %s %s" % (key, shlex.quote(value)))
+                    cfg.write("%s=%s\n" % (key, shlex.quote(value)))
+                    #_run("npm config set %s %s" % (key, shlex.quote(value)))
             if configs:
                 for key, value in configs:
-                    _run("npm config set %s %s" % (key, shlex.quote(value)))
+                    cfg.write("%s=%s\n" % (key, shlex.quote(value)))
+                    # _run("npm config set %s %s" % (key, shlex.quote(value)))
+            cfg.close()
             if args:
                 for key, value in args:
-- 2.7.4

Are there any side effects that I did not stumble over yet? And I'd LOVE to have these calls running in a thread-pool for better performance...

Secondly, our projects are based on typescript, so a native compile step is necessary to create a compiled version for packing. We experimented with a separate release branch to check in compiled versions, but this is not easy to handle. I played around with npm.bbclass and found a way to extend configure (!) with a call to our build script before packaging: 

diff --git a/meta/classes/npm.bbclass b/meta/classes/npm.bbclass
index 068032a1e5..31535098cf 100644
--- a/meta/classes/npm.bbclass
+++ b/meta/classes/npm.bbclass
@@ -170,6 +170,11 @@ python npm_do_configure() {
     # Configure the main package
     with tempfile.TemporaryDirectory() as tmpdir:
+        # install all (native) build dependencies, overrides npm cache:
+        ret = os.system("npm i")
+        # run build step:
+        env.run("npm run build", args=[], workdir=d.getVar("S"))
         tarball = npm_pack(env, d.getVar("S"), tmpdir)
         npm_unpack(tarball, d.getVar("NPM_PACKAGE"), d)

As we have plain JS packages as well, I put the modified configure() in a subclass and this works for us, but it does not look like a clean solution to me. How do you other IoT'ers address this situation?


VoXel Interaction Design  |  www.voxel.at
DI Dr.techn. Simon Vogl   |  simon@...
Tomaschekweg 46           |  +43 650 2323 555
A-4040 Linz - Austria     |  
Office address: Industriezeile 35, 4020 Linz (2nd floor)

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