Use docker for _some_ testing?

Use docker for _some_ testing?

[Duy Nguyen]

The story started with my problem on Debian, which I didn't have and
didn't want to install a Debian VM just for that problem. So I made a
docker image with the following script.

Which makes me think, could we use something like this to make sure
people (on Linux) can test more obscure cases? Sometimes there are
featues that require some dependencies that are not always present on
the developer's machine (http server is a big one, locales come close
second, then there will be lmdb and watchman in future...). With this,
said developer can do a final test run in docker covering as much as
possible.

Of course it can't cover everything. Different compiler versions are
out. OS-specific changes are out (but wine would be still good to test
some aspect of Windows port, or at least make sure it builds)

Comments?

-- 8< --
diff --git a/contrib/docker/locale.gen b/contrib/docker/locale.gen
new file mode 100644
index 0000000..ef08e00
--- /dev/null
+++ b/contrib/docker/locale.gen
@@ -0,0 +1,2 @@
+is_IS.UTF-8 UTF-8
+is_IS ISO-8859-1
\ No newline at end of file
diff --git a/contrib/docker/run.sh b/contrib/docker/run.sh
new file mode 100755
index 0000000..83e5679
--- /dev/null
+++ b/contrib/docker/run.sh
@@ -0,0 +1,30 @@
+#!/bin/sh
+
+die() {
+	echo "$@" >&2
+	exit 1
+}
+
+build_debian() {
+	cat >Dockerfile <<-EOF
+	FROM debian:latest
+	RUN apt-get update && \
+		apt-get install -y libcurl4-gnutls-dev libexpat1-dev \
+		gettext libz-dev libssl-dev build-essential
+	RUN apt-get install -y locales
+	COPY locale.gen /etc/locale.gen
+	RUN locale-gen
+	RUN groupadd -r $(id -gn) -g $(id -g) && \
+		useradd -u $(id -u) -r -d "$HOME" -g $(id -g) -s /sbin/nologin $(id -un)
+	USER $(id -un)
+	EOF
+	docker build -t $IMAGE .  || die "failed to build docker image"
+}
+
+DISTRO=debian
+IMAGE=git-$DISTRO-$(id -un)
+ROOT="$(realpath $(git rev-parse --show-cdup))"
+
+test "$(docker images --format='{{.Repository}}' $IMAGE)" = $IMAGE || \
+	build_$DISTRO
+docker run -it --rm -v "$ROOT":"$ROOT" -w "$(pwd)" $IMAGE bash
-- 8< --
--
Duy

Re: Use docker for _some_ testing?

[Junio C Hamano]

Duy Nguyen <pclouds@gmail.com> writes:

> The story started with my problem on Debian, which I didn't have and
> didn't want to install a Debian VM just for that problem. So I made a
> docker image with the following script.
>
> Which makes me think, could we use something like this to make sure
> people (on Linux) can test more obscure cases? Sometimes there are
> featues that require some dependencies that are not always present on
> the developer's machine (http server is a big one, locales come close
> second, then there will be lmdb and watchman in future...). With this,
> said developer can do a final test run in docker covering as much as
> possible.
>
> Of course it can't cover everything. Different compiler versions are
> out. OS-specific changes are out (but wine would be still good to test
> some aspect of Windows port, or at least make sure it builds)
>
> Comments?

Nice.

> -- 8< --
> diff --git a/contrib/docker/locale.gen b/contrib/docker/locale.gen
> new file mode 100644
> index 0000000..ef08e00
> --- /dev/null
> +++ b/contrib/docker/locale.gen
> @@ -0,0 +1,2 @@
> +is_IS.UTF-8 UTF-8
> +is_IS ISO-8859-1
> \ No newline at end of file
> diff --git a/contrib/docker/run.sh b/contrib/docker/run.sh
> new file mode 100755
> index 0000000..83e5679
> --- /dev/null
> +++ b/contrib/docker/run.sh
> @@ -0,0 +1,30 @@
> +#!/bin/sh
> +
> +die() {
> +	echo "$@" >&2
> +	exit 1
> +}
> +
> +build_debian() {
> +	cat >Dockerfile <<-EOF
> +	FROM debian:latest
> +	RUN apt-get update && \
> +		apt-get install -y libcurl4-gnutls-dev libexpat1-dev \
> +		gettext libz-dev libssl-dev build-essential
> +	RUN apt-get install -y locales
> +	COPY locale.gen /etc/locale.gen
> +	RUN locale-gen
> +	RUN groupadd -r $(id -gn) -g $(id -g) && \
> +		useradd -u $(id -u) -r -d "$HOME" -g $(id -g) -s /sbin/nologin $(id -un)
> +	USER $(id -un)
> +	EOF
> +	docker build -t $IMAGE .  || die "failed to build docker image"
> +}
> +
> +DISTRO=debian
> +IMAGE=git-$DISTRO-$(id -un)
> +ROOT="$(realpath $(git rev-parse --show-cdup))"
> +
> +test "$(docker images --format='{{.Repository}}' $IMAGE)" = $IMAGE || \
> +	build_$DISTRO
> +docker run -it --rm -v "$ROOT":"$ROOT" -w "$(pwd)" $IMAGE bash
> -- 8< --
> --
> Duy

Re: Use docker for _some_ testing?

[Jeff King]

On Wed, Jun 22, 2016 at 09:01:55PM +0200, Duy Nguyen wrote:

> Which makes me think, could we use something like this to make sure
> people (on Linux) can test more obscure cases? Sometimes there are
> featues that require some dependencies that are not always present on
> the developer's machine (http server is a big one, locales come close
> second, then there will be lmdb and watchman in future...). With this,
> said developer can do a final test run in docker covering as much as
> possible.

Neat idea. This should also cover some other distro-specific issues like
"what's your /bin/sh look like", etc. It's a lighter-weight alternative
to testing alternate distros in a VM.

But I think most of the interesting cases are more exotic than
distro-to-distro. Things like HFS+ normalization, or weird shell
toolchains on proprietary Unixes (but maybe there are docker images for
those systems?).

So I dunno if it would prove that useful for day to day use or not.

> +ROOT="$(realpath $(git rev-parse --show-cdup))"

I tried running this as contrib/docker/run.sh, which complained here,
because --show-cdup is empty.

> +test "$(docker images --format='{{.Repository}}' $IMAGE)" = $IMAGE || \
> +	build_$DISTRO

My docker complained that it doesn't know --format. I guess I might just
have an old one (it's whatever is in Debian unstable, which is 1.8.3).

Not things you need to fix, but just comments for anybody else fiddling
with it.

-Peff

Re: Use docker for _some_ testing?

[Duy Nguyen]

On Wed, Jun 22, 2016 at 9:59 PM, Jeff King <peff@peff.net> wrote:
> On Wed, Jun 22, 2016 at 09:01:55PM +0200, Duy Nguyen wrote:
>
>> Which makes me think, could we use something like this to make sure
>> people (on Linux) can test more obscure cases? Sometimes there are
>> featues that require some dependencies that are not always present on
>> the developer's machine (http server is a big one, locales come close
>> second, then there will be lmdb and watchman in future...). With this,
>> said developer can do a final test run in docker covering as much as
>> possible.
>
> Neat idea. This should also cover some other distro-specific issues like
> "what's your /bin/sh look like", etc. It's a lighter-weight alternative
> to testing alternate distros in a VM.

It's lighter-weight and also helps skip preparation. Everything is
scripted, if you want distro X, it's just one command away. The VM way
would require you to go through installation process with lots of
clicking and typing (unless you go full cloud solution like OpenStack,
not really suited for single dev use).

It's not just distro-specific. Not every developer has enough stuff
installed to run all tests. My machine is svn-free for example so I
never run those tests. Same story for pcre (have it but not enable it
in git...). We can try to run both gettext and no-gettext
configuration... Devs still have to install docker this way, but at
least i could keep my laptop "clean" from unwanted stuff and still be
able to run lots of tests.

> But I think most of the interesting cases are more exotic than
> distro-to-distro. Things like HFS+ normalization, or weird shell
> toolchains on proprietary Unixes (but maybe there are docker images for
> those systems?).

I don't follow docker closely, but if it's still a container
technology (i.e. sharing host kernel) then different OSes are out of
question.

> So I dunno if it would prove that useful for day to day use or not.
-- 
Duy