From c83387652b2bc12064ca56de01db76b24a27fac1 Mon Sep 17 00:00:00 2001
From: Tigor Hutasuhut <tigor.hutasuhut@gmail.com>
Date: Thu, 15 Aug 2024 15:07:17 +0700
Subject: [PATCH] api: implemented CountSubreddits API endpoint

---
 go/api/subreddits_count.go                   | 50 ++++++++++++++++++++
 go/converts/subreddit.go                     | 15 ++++++
 go/converts/utils.go                         |  4 ++
 go/server/subreddit_handlers.go              | 14 ++++++
 schemas/proto/subreddits/v1/subreddits.proto |  6 +++
 5 files changed, 89 insertions(+)
 create mode 100644 go/api/subreddits_count.go

diff --git a/go/api/subreddits_count.go b/go/api/subreddits_count.go
new file mode 100644
index 0000000..d73cda8
--- /dev/null
+++ b/go/api/subreddits_count.go
@@ -0,0 +1,50 @@
+package api
+
+import (
+	"context"
+
+	. "github.com/go-jet/jet/v2/sqlite"
+	. "github.com/tigorlazuardi/bluemage/go/gen/jet/table"
+	"github.com/tigorlazuardi/bluemage/go/pkg/errs"
+	"github.com/tigorlazuardi/bluemage/go/pkg/telemetry"
+)
+
+type CountSubredditsRequest struct {
+	Search   string
+	Disabled *bool
+}
+
+func (c CountSubredditsRequest) Statement() SelectStatement {
+	cond := Bool(true)
+	if c.Search != "" {
+		cond.AND(Subreddits.Name.LIKE(String("%" + c.Search + "%")))
+	}
+	if c.Disabled != nil {
+		disabled := *c.Disabled
+		if disabled {
+			cond.AND(Subreddits.Disabled.EQ(Int(1)))
+		} else {
+			cond.AND(Subreddits.Disabled.EQ(Int(0)))
+		}
+	}
+
+	return SELECT(COUNT(Subreddits.Name)).WHERE(cond)
+}
+
+func (api *API) CountSubreddits(ctx context.Context, request CountSubredditsRequest) (count int64, err error) {
+	ctx, span := tracer.Start(ctx, "CountSubreddits")
+	defer func() { telemetry.EndWithStatus(span, err) }()
+
+	stmt := request.Statement()
+	query, args := stmt.Sql()
+	err = api.DB.QueryRowContext(ctx, query, args...).Scan(&count)
+	if err != nil {
+		err = errs.Wrapw(err, "failed to count subreddits",
+			"request", request,
+			"query", stmt.DebugSql(),
+		)
+		return count, err
+	}
+
+	return count, err
+}
diff --git a/go/converts/subreddit.go b/go/converts/subreddit.go
index ba09b11..871cf8c 100644
--- a/go/converts/subreddit.go
+++ b/go/converts/subreddit.go
@@ -2,6 +2,7 @@ package converts
 
 import (
 	"github.com/aarondl/opt/omit"
+	"github.com/tigorlazuardi/bluemage/go/api"
 	"github.com/tigorlazuardi/bluemage/go/gen/models"
 	subreddits "github.com/tigorlazuardi/bluemage/go/gen/proto/subreddits/v1"
 )
@@ -25,9 +26,13 @@ import (
 // goverter:extend StringToOmitString
 // goverter:extend SubredditTypeToString
 // goverter:extend SubredditTypeToOmitString
+// goverter:extend SubredditsDisabledFilterToPtrBool
 type SubredditConverter interface {
 	// goverter:ignore CreatedAt UpdatedAt CoverImageID
 	CreateSubredditRequestToModelsSubredditSetter(*subreddits.CreateSubredditRequest) *models.SubredditSetter
+
+	// goverter:useZeroValueOnPointerInconsistency
+	ProtoCountSubredditsRequestToAPICountSubredditsRequest(*subreddits.CountSubredditsRequest) api.CountSubredditsRequest
 }
 
 func SubredditTypeToString(subType subreddits.SubredditType) string {
@@ -43,3 +48,13 @@ func SubredditTypeToOmitString(subType subreddits.SubredditType) omit.Val[string
 	}
 	return omit.From("r")
 }
+
+func SubredditsDisabledFilterToPtrBool(filter subreddits.DisabledFilter) *bool {
+	switch filter {
+	case subreddits.DisabledFilter_DISABLED_FILTER_TRUE:
+		return boolPtr(true)
+	case subreddits.DisabledFilter_DISABLED_FILTER_FALSE:
+		return boolPtr(false)
+	}
+	return nil
+}
diff --git a/go/converts/utils.go b/go/converts/utils.go
index 500c339..b5d1d2e 100644
--- a/go/converts/utils.go
+++ b/go/converts/utils.go
@@ -78,3 +78,7 @@ func BoolToOmitInt8(b bool) omit.Val[int8] {
 func Int8ToBool(i int8) bool {
 	return i > 0
 }
+
+func boolPtr(b bool) *bool {
+	return &b
+}
diff --git a/go/server/subreddit_handlers.go b/go/server/subreddit_handlers.go
index 6ba1ebe..7fae7f1 100644
--- a/go/server/subreddit_handlers.go
+++ b/go/server/subreddit_handlers.go
@@ -19,6 +19,20 @@ type SubredditHandler struct {
 	v1connect.UnimplementedSubredditsServiceHandler
 }
 
+// Count the existing subreddits using given filter.
+// Default values count all.
+func (su *SubredditHandler) CountSubreddits(ctx context.Context, request *connect.Request[subreddits.CountSubredditsRequest]) (*connect.Response[subreddits.CountSubredditsResponse], error) {
+	countRequest := subredditConverter.ProtoCountSubredditsRequestToAPICountSubredditsRequest(request.Msg)
+	count, err := su.API.CountSubreddits(ctx, countRequest)
+	if err != nil {
+		return nil, errs.IntoConnectError(err)
+	}
+	resp := &subreddits.CountSubredditsResponse{
+		Count: count,
+	}
+	return connect.NewResponse(resp), nil
+}
+
 // CreateSubreddit creates a new subreddit
 // Returns the subreddit name.
 //
diff --git a/schemas/proto/subreddits/v1/subreddits.proto b/schemas/proto/subreddits/v1/subreddits.proto
index f2950ee..0fbecaa 100644
--- a/schemas/proto/subreddits/v1/subreddits.proto
+++ b/schemas/proto/subreddits/v1/subreddits.proto
@@ -2,6 +2,7 @@ syntax = "proto3";
 
 package subreddits.v1;
 
+import "subreddits/v1/count.proto";
 import "subreddits/v1/create.proto";
 import "subreddits/v1/delete.proto";
 import "subreddits/v1/get.proto";
@@ -50,4 +51,9 @@ service SubredditsService {
   // Returns error with connect.CodeNotFound if subreddit does not exist.
   // So this rpc endpoint also acts to check subreddit's existence.
   rpc ResolveSubredditName(ResolveSubredditNameRequest) returns (ResolveSubredditNameResponse);
+
+  // Count the existing subreddits using given filter.
+  //
+  // Default values count all.
+  rpc CountSubreddits(CountSubredditsRequest) returns (CountSubredditsResponse);
 }