Php: Unable to build some extensions on php5.6-alpine

[solocommand]

Hey folks, I'm new to docker and trying to see if it's feasible to move our infrastructure to run in docker containers. I've created an image from the php5.6-alpine image, but I'm having trouble getting the date extension to build. Simple test case:

echo "FROM php:5.6-alpine" > Dockerfile
docker build . -t alpine
docker run alpine docker-php-ext-install date

nets the following output:

fetch http://dl-cdn.alpinelinux.org/alpine/v3.4/main/x86_64/APKINDEX.tar.gz
fetch http://dl-cdn.alpinelinux.org/alpine/v3.4/community/x86_64/APKINDEX.tar.gz
(1/31) Installing m4 (1.4.17-r1)
(2/31) Installing perl (5.22.2-r0)
(3/31) Installing autoconf (2.69-r0)
(4/31) Installing pkgconf (0.9.12-r0)
(5/31) Installing pkgconfig (0.25-r1)
(6/31) Installing dpkg-dev (1.18.7-r0)
(7/31) Installing libbz2 (1.0.6-r5)
(8/31) Installing dpkg (1.18.7-r0)
(9/31) Installing libmagic (5.27-r0)
(10/31) Installing file (5.27-r0)
(11/31) Installing libgcc (5.3.0-r0)
(12/31) Installing libstdc++ (5.3.0-r0)
(13/31) Installing binutils-libs (2.26-r1)
(14/31) Installing binutils (2.26-r1)
(15/31) Installing gmp (6.1.0-r0)
(16/31) Installing isl (0.14.1-r0)
(17/31) Installing libgomp (5.3.0-r0)
(18/31) Installing libatomic (5.3.0-r0)
(19/31) Installing mpfr3 (3.1.2-r0)
(20/31) Installing mpc1 (1.0.3-r0)
(21/31) Installing gcc (5.3.0-r0)
(22/31) Installing musl-dev (1.1.14-r14)
(23/31) Installing libc-dev (0.7-r0)
(24/31) Installing g++ (5.3.0-r0)
(25/31) Installing make (4.1-r1)
(26/31) Installing libpcre16 (8.38-r1)
(27/31) Installing libpcre32 (8.38-r1)
(28/31) Installing libpcrecpp (8.38-r1)
(29/31) Installing pcre-dev (8.38-r1)
(30/31) Installing re2c (0.14.3-r0)
(31/31) Installing .phpize-deps (0)
Executing busybox-1.24.2-r13.trigger
OK: 222 MiB in 57 packages
+ cd date
+ phpize
Cannot find config.m4.
Make sure that you run '/usr/local/bin/phpize' in the top level source directory of the module

Looking at the /usr/src/php/ext/date folder there is no config.m4 file, though there is a config0.m4. Any ideas?

[solocommand]

The same appears to be true of ereg, libxml, mysqlnd, openssl, pcre and zlib.

[yosifkit]

All 6 of those modules (ereg, libxml, mysqlnd, openssl, pcre and zlib) are enabled by default (docker run -it --rm php:5.6-alpine php -i). Even date shows up in php -i.

date

date/time support => enabled
"Olson" Timezone Database Version => 2016.10
Timezone Database => internal
Default timezone => UTC

We enable many of them since they can't be added after.

[Arkemlar]

All 6 of those modules (ereg, libxml, mysqlnd, openssl, pcre and zlib) are enabled by defaul

@yosifkit This is deffinetely should be mentioned in docker page! Wasted some hours trying to handle installation issues with openssl:

Cannot find config.m4. 
Make sure that you run '/usr/local/bin/phpize' in the top level source directory of the module