From: sgf <sgf.dma@gmail.com>
Date: Tue, 1 Nov 2022 16:11:24 +0000 (+0300)
Subject: chg(balancer): Move Requester implementation to separate package too.
X-Git-Url: https://gitweb.sgf-dma.tk/?a=commitdiff_plain;h=e5fcbefbbd565815468f7fffab8438cb1e8d4ea8;p=go.git

chg(balancer): Move Requester implementation to separate package too.
---

diff --git a/concurrency-is-not-parallelism/balancer_v2/balancer/balancer.go b/concurrency-is-not-parallelism/balancer_v2/balancer/balancer.go
index cc295d9..a09a776 100644
--- a/concurrency-is-not-parallelism/balancer_v2/balancer/balancer.go
+++ b/concurrency-is-not-parallelism/balancer_v2/balancer/balancer.go
@@ -8,7 +8,12 @@ import (
 )
 
 // Requester is an interface to requester.
-// It's used by WorkRunner's implementation, not by balancer itself.
+// It's used by WorkRunner's implementation in 'balancer/worker' package, not
+// by balancer itself. But i can't move this definition to 'balancer/worker',
+// because that'll create cyclic package dependencies: balancer needs
+// 'Requester' interface in various places, thus needs to import
+// 'balancer/worker', but worker needs 'WorkRunner' interface for implementing
+// it, thus needs to import 'balancer'.
 type Requester interface {
     Fn() interface{}
     Send(interface{}) // Send result of Fn() back to requester.
diff --git a/concurrency-is-not-parallelism/balancer_v2/balancer/requester/go.mod b/concurrency-is-not-parallelism/balancer_v2/balancer/requester/go.mod
new file mode 100644
index 0000000..398bbc2
--- /dev/null
+++ b/concurrency-is-not-parallelism/balancer_v2/balancer/requester/go.mod
@@ -0,0 +1,7 @@
+module balancer/requester
+
+go 1.15
+
+replace balancer => ../../balancer
+
+require balancer v0.0.0-00010101000000-000000000000
diff --git a/concurrency-is-not-parallelism/balancer_v2/balancer/requester/requester.go b/concurrency-is-not-parallelism/balancer_v2/balancer/requester/requester.go
new file mode 100644
index 0000000..593b98a
--- /dev/null
+++ b/concurrency-is-not-parallelism/balancer_v2/balancer/requester/requester.go
@@ -0,0 +1,54 @@
+
+package requester
+
+import (
+    "fmt"
+    "time"
+    "math/rand"
+    "balancer"
+)
+
+type request struct {
+    reqFn func() int    // what to compute for this particular request.
+    num int             // Used for request identification.
+    c chan int          // channel for obtaining results back from worker.
+}
+
+func (r request) String() string {
+    return fmt.Sprintf("R %.2d", r.num)
+}
+
+var _ balancer.Requester = (*request)(nil)
+
+func (r *request) Fn() interface{} {
+    fmt.Printf("%v: Fn()..\n", r)
+    return interface{}(r.reqFn())
+}
+
+func (r *request) Send(res interface{}) {
+    r.c <- res.(int)
+}
+
+func furtherProcess(r *request, result int) {
+    fmt.Printf("%v: further processing result %v..\n", r, result)
+}
+
+func Generate(work chan<- balancer.Requester) {
+    c := make(chan int)
+    reqNum := 0
+    for {
+        t := rand.Intn(5)
+        fmt.Printf("Generate(): sleeping for %v secs\n", t)
+        time.Sleep(time.Duration(t) * time.Second)
+
+        f := func () int { fmt.Printf("... computing req num %v\n", reqNum); return reqNum }
+        req := &request{reqFn: f, num: reqNum, c: c}
+        fmt.Printf("Generate() '%v': sending\n", req)
+        work <- req
+        result := <-c
+        fmt.Printf("Generate() '%v': received result %v\n", req, result)
+        furtherProcess(req, result)
+        reqNum++
+    }
+}
+
diff --git a/concurrency-is-not-parallelism/balancer_v2/balancer_v2.go b/concurrency-is-not-parallelism/balancer_v2/balancer_v2.go
index a2f3ecd..d92d138 100644
--- a/concurrency-is-not-parallelism/balancer_v2/balancer_v2.go
+++ b/concurrency-is-not-parallelism/balancer_v2/balancer_v2.go
@@ -2,59 +2,13 @@
 package main
 
 import (
-    "fmt"
-    "time"
-    "math/rand"
     "balancer"
     "balancer/worker"
+    "balancer/requester"
 )
 
 // FIXME: Add buffers to channels. What changes?
 
-type request struct {
-    reqFn func() int    // what to compute for this particular request.
-    num int             // Used for request identification.
-    c chan int          // channel for obtaining results back from worker.
-}
-
-func (r request) String() string {
-    return fmt.Sprintf("R %.2d", r.num)
-}
-
-var _ balancer.Requester = (*request)(nil)
-
-func (r *request) Fn() interface{} {
-    fmt.Printf("%v: Fn()..\n", r)
-    return interface{}(r.reqFn())
-}
-
-func (r *request) Send(res interface{}) {
-    r.c <- res.(int)
-}
-
-func furtherProcess(r *request, result int) {
-    fmt.Printf("%v: further processing result %v..\n", r, result)
-}
-
-func requester(work chan<- balancer.Requester) {
-    c := make(chan int)
-    reqNum := 0
-    for {
-        t := rand.Intn(5)
-        fmt.Printf("requester(): sleeping for %v secs\n", t)
-        time.Sleep(time.Duration(t) * time.Second)
-
-        f := func () int { fmt.Printf("... computing req num %v\n", reqNum); return reqNum }
-        req := &request{reqFn: f, num: reqNum, c: c}
-        fmt.Printf("requester() '%v': sending\n", req)
-        work <- req
-        result := <-c
-        fmt.Printf("requester() '%v': received result %v\n", req, result)
-        furtherProcess(req, result)
-        reqNum++
-    }
-}
-
 var nWorker int = 4
 
 func main() {
@@ -66,7 +20,7 @@ func main() {
         workers[i] = &worker.Runner{Requests: c}
     }
     b := balancer.InitBalancer(workers)
-    go requester(work)
+    go requester.Generate(work)
     b.Balance(work)
 }
 
diff --git a/concurrency-is-not-parallelism/balancer_v2/go.mod b/concurrency-is-not-parallelism/balancer_v2/go.mod
index 9a4e6e1..efdfb32 100644
--- a/concurrency-is-not-parallelism/balancer_v2/go.mod
+++ b/concurrency-is-not-parallelism/balancer_v2/go.mod
@@ -8,5 +8,8 @@ replace balancer/worker => ./balancer/worker
 
 require (
 	balancer v0.0.0-00010101000000-000000000000
+	balancer/requester v0.0.0-00010101000000-000000000000
 	balancer/worker v0.0.0-00010101000000-000000000000
 )
+
+replace balancer/requester => ./balancer/requester