service: support init jobsv0.3.1

1 files changed, 28 insertions, 1 deletions

diff --git a/service/app_runner.go b/service/app_runner.go
index 99ae263..e1eb98b 100644
--- a/service/app_runner.go
+++ b/service/app_runner.go
@@ -2,6 +2,7 @@ package service
 
 import (
         "context"
+        "fmt"
         "os"
         "os/signal"
         "sync"
@@ -10,12 +11,15 @@ import (
 
 type AppRunnerLogger interface {
         Info(...interface{})
+        Error(...interface{})
 }
 
+type SyncRunnerFunc func() error
 type RunnerFunc func(context.Context, *sync.WaitGroup) error
 
 type AppRunner struct {
         Logger         AppRunnerLogger
+        initJobs       []SyncRunnerFunc
         jobs           []RunnerFunc
         backgroundJobs []RunnerFunc
         wg             *sync.WaitGroup
@@ -26,6 +30,7 @@ type AppRunner struct {
 
 func NewAppRunner(ctx context.Context, logger AppRunnerLogger) *AppRunner {
         r := &AppRunner{
+                initJobs:       []SyncRunnerFunc{},
                 jobs:           []RunnerFunc{},
                 backgroundJobs: []RunnerFunc{},
                 wg:             &sync.WaitGroup{},
@@ -42,6 +47,16 @@ func NewAppRunner(ctx context.Context, logger AppRunnerLogger) *AppRunner {
         return r
 }
 
+func (r *AppRunner) AddInitJob(f SyncRunnerFunc) {
+        r.initJobs = append(r.initJobs, f)
+}
+
+func (r *AppRunner) AddInitJobs(jobs []SyncRunnerFunc) {
+        for _, j := range jobs {
+                r.AddInitJob(j)
+        }
+}
+
 func (r *AppRunner) AddJob(f RunnerFunc) {
         r.jobs = append(r.jobs, f)
 }
@@ -56,7 +71,7 @@ func (r *AppRunner) AddBackgroundJob(f RunnerFunc) {
         r.backgroundJobs = append(r.backgroundJobs, f)
 }
 
-func (r *AppRunner) goRunPanic(f func(context.Context, *sync.WaitGroup) error) {
+func (r *AppRunner) goRunPanic(f RunnerFunc) {
         errs := make(chan error)
         go func() { errs <- f(r.ctx, r.wg) }()
         select {
@@ -67,6 +82,18 @@ func (r *AppRunner) goRunPanic(f func(context.Context, *sync.WaitGroup) error) {
 }
 
 func (r *AppRunner) RunForever(enableBg bool) {
+        // Init jobs must run before main jobs start, the should return on
+        // success but will panic on error
+        r.Logger.Info("Starting initialization jobs")
+        for _, f := range r.initJobs {
+                if err := f(); err != nil {
+                        r.Logger.Error(fmt.Sprintf("Init job failed: %s", err))
+                        return
+                }
+        }
+        r.Logger.Info("Initialization jobs finished")
+
+        r.Logger.Info("Starting main jobs")
         for _, f := range r.jobs {
                 r.goRunPanic(f)
         }