jschoubben
12a5e7be73
build-agent
The mesh's build machine as a role every machine can hold (novox/hq ADR 0190). It holds the node seat
node-build-agent: every holder pulls one build at a time from the role's one work queue when it is
idle, so a tier of many images is built by as many machines as hold the seat and are online, and a
machine that is off builds nothing and blocks nothing. The controller asks the role, never a machine;
the outcome names the machine that built it.
What a holding machine needs is what the builder always needed, said here once: a container runtime
(the socket is mounted), the artifact store and the package registry as provisions, a workspace, and
the bus credential. The code is cmd/mesh-builder in the mesh-controller repository, compiled from
that repository's main (build.artifacts[].context); this module ships the packaging.
Assign it to every machine with a container runtime. It replaces builder, the one-holder form of the
same thing; retire that once this is assigned where it was.
A send that replaces the agent's container does not throw away the build it runs: the container declares
busy as /usr/local/bin/mesh-builder busy (novox/hq ADR 0335). The node-engine asks it before replacing it; from that
ask the agent takes no new build, the node-engine leaves it running while it says a build is in hand, and
replaces it once it says idle, or after 15 minutes at the latest.