Files
mesh-catalog/modules/mesh-build-go/buildstep/capacity.go
T
jschoubben 9c57f7afb3 mesh-build-go publishes the build runner as its own package, so the other build modules share it without mesh-sdk (ADR 0593 §1)
The runner, the toolchain guard, the fetch, the parsers, buildcpu, the conformance kit and mesh-pack move from mesh-sdk's
buildstep into modules/mesh-build-go/buildstep (own go.mod). mesh-build-go, mesh-build-node and mesh-build-image require it
by a same-repository replace; what the delivery parts read (the failure contract, the fetch request, the stale sweep, the
module tree shape, NewID, CapacitySetting) stays imported from mesh-sdk as sdkstep.

Claude-Session: https://claude.ai/code/session_01NcbgfJ9Gum47zkFKWRaovL
2026-11-02 18:22:41 +01:00

58 lines
1.7 KiB
Go

package buildstep
import (
sdkstep "git.novox.be/novox/mesh-sdk/go/buildstep"
"encoding/json"
"fmt"
"os"
)
// NodeCapacity is the node's build capacity, read from the module's settings file at path at every call, so a change
// takes effect at the next pull. No path, no file value, or a value that is not a whole number of at least 0 gives 0 and
// a value that cannot be read says why: pulling on a setting nobody can read could build on a node that must not.
func NodeCapacity(path, node string, logf func(string, ...any)) func() int {
say := func(format string, args ...any) {
if logf != nil {
logf(format, args...)
}
}
return func() int {
n, err := ReadCapacity(path)
if err != nil {
say("%v, so %s pulls nothing", err, node)
return 0
}
return n
}
}
// ReadCapacity is the capacity the settings file at path holds, and why it cannot be read when it cannot (then 0).
func ReadCapacity(path string) (int, error) {
if path == "" {
return 0, nil
}
raw, err := os.ReadFile(path)
if err != nil {
return 0, fmt.Errorf("the build capacity cannot be read: %w", err)
}
var s map[string]json.RawMessage
if err := json.Unmarshal(raw, &s); err != nil {
return 0, fmt.Errorf("the settings file %s is not JSON: %w", path, err)
}
return capacityOf(s[sdkstep.CapacitySetting])
}
// capacityOf is the capacity a config value holds: absent or null is 0; anything but a whole number of at least 0 is
// refused, naming it.
func capacityOf(value json.RawMessage) (int, error) {
if len(value) == 0 || string(value) == "null" {
return 0, nil
}
var n int
if err := json.Unmarshal(value, &n); err != nil || n < 0 {
return 0, fmt.Errorf("the build capacity %s is not a whole number of asks at once, 0 or more", value)
}
return n, nil
}