Build-in-container instructions missing mariner-repos directory (and other notes)

[dagood]

https://github.com/microsoft/CBL-MarinerTutorials/tree/main/build-in-container

I tried running ./build-in-container/mariner-docker-builder.sh -c then ./build-in-container/mariner-docker-builder.sh -b from the root of the repo. It wasn't clear to me where you're meant to run it from (somewhere outside the repo?) based on this:

# Setup the container for 1st use
./CBL-MarinerTutorials/build-in-container/mariner-docker-builder.sh -t

After that, I got an error in the middle of the build, but it was a bit hard to understand what was going on from the end of the output because there's a lot of Go output to scroll through:

------------ Building Mariner toolkit ------------
++ echo '------------ Building Mariner toolkit ------------'
+++ nproc
++ make -j8 -C CBL-Mariner/toolkit package-toolkit BUILD_DIR=/mariner/build CHROOT_DIR=/temp/DockerStage/ CONCURRENT_PACKAGE_BUILDS=12 CONFIG_FILE= LOG_LEVEL=info OUT_DIR=/mariner/out REBUILD_TOOLS=y
make: Entering directory '/mariner/CBL-Mariner/toolkit'
SUDO_USER is not set, running 'go get' as user ''
echo "mariner-official-base.repo mariner-microsoft.repo" | sed -E 's:([^ ]+[.]repo):/mariner/SPECS/mariner-repos/\1:g' | xargs cat > /mariner/CBL-Mariner/toolkit/scripts/sodiff/sodiff.repo
cat: /mariner/SPECS/mariner-repos/mariner-official-base.repo: No such file or directory
cat: /mariner/SPECS/mariner-repos/mariner-microsoft.repo: No such file or directory
make: *** [/mariner/CBL-Mariner/toolkit/scripts/analysis.mk:73: /mariner/CBL-Mariner/toolkit/scripts/sodiff/sodiff.repo] Error 123
...
go: downloading github.com/google/uuid v1.3.0
go: downloading github.com/pkg/browser v0.0.0-20210911075715-681adbf594b8
go: downloading golang.org/x/net v0.18.0
go: downloading github.com/golang-jwt/jwt/v5 v5.0.0
make: Leaving directory '/mariner/CBL-Mariner/toolkit'

I randomly guessed at adding this line to build-in-container/scripts/setup.sh to get a bit further:

         echo "------------ Building Mariner toolkit ------------"
+        cp -r CBL-Mariner/SPECS/mariner-repos SPECS/ && \
         make -j$(nproc) \

Then I got through Adding RPM to worker chroot and eventually it seemed not to find any specs. I left the hello_world_demo in place and thought it would build:

INFO[0003][rpmssnapshot] Generating RPMs snapshot from specs inside (/mariner/SPECS). 
INFO[0003][rpmssnapshot] Found 0 compatible specs.                    
INFO[0003][rpmssnapshot] The specs build 0 packages in total.         

(I was getting this working to have a local dev loop for microsoft/azurelinux#7446, but for the time being the buddy build seems fine.)

[dagood]

A step that might also be nice to include is docker pull mcr.microsoft.com/cbl-mariner/base/core:2.0. I was on a version where running tdnf install -y curl would cause any future tdnf calls to fail due to a symbol mismatch.