Hexists

README.md

@@ -142,6 +142,12 @@ SELECT CLUSTER_COUNTKEYSINSLOT(<key_id>)
 SELECT DBSIZE()
 ```
 
+### HEXISTS
+
+```sql
+SELECT HEXISTS('some-key','some-field')
+```
+
 ### LLEN
 
 ```sql

commands.md

@@ -108,7 +108,7 @@
 | GETSET                        | 🚧
 | HDEL                          | 🚧
 | HELLO                         | 🚧
-| HEXISTS                       | 🚧
+| HEXISTS                       | [`HEXISTS`](https://github.com/augmentable-dev/reqlite/tree/main/internal/redis/hexists)
 | HGET                          | 🚧
 | HGETALL                       | ✅ [`HGETALL`](https://github.com/augmentable-dev/reqlite/tree/main/internal/redis/hgetall)
 | HINCRBY                       | 🚧

internal/redis/hexists/hexists.go

@@ -0,0 +1,39 @@
+package hexists
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/go-redis/redis/v8"
+	"go.riyazali.net/sqlite"
+)
+
+type hexists struct {
+	rdb *redis.Client
+}
+
+func (f *hexists) Args() int           { return -1 }
+func (f *hexists) Deterministic() bool { return false }
+func (f *hexists) Apply(ctx *sqlite.Context, values ...sqlite.Value) {
+	var (
+		key   string
+		field string
+	)
+
+	if len(values) >= 2 {
+		key = values[0].Text()
+		field = values[1].Text()
+	} else {
+		ctx.ResultError(fmt.Errorf("must supply argument to redis hexists command (key,field) "))
+		return
+	}
+
+	result := f.rdb.HExists(context.TODO(), key, field)
+
+	ctx.ResultText(fmt.Sprintf("%+q", result))
+}
+
+// New returns a sqlite function for reading the contents of a file
+func New(rdb *redis.Client) sqlite.Function {
+	return &hexists{rdb}
+}

internal/redis/hexists/hexists_test.go

@@ -0,0 +1,46 @@
+package hexists_test
+
+import (
+	"testing"
+
+	"github.com/augmentable-dev/reqlite/internal/redis/hexists"
+	_ "github.com/augmentable-dev/reqlite/internal/sqlite"
+	"github.com/go-redis/redismock/v8"
+	"github.com/jmoiron/sqlx"
+	_ "github.com/mattn/go-sqlite3"
+	"go.riyazali.net/sqlite"
+)
+
+func TestHExists(t *testing.T) {
+	rdb, mock := redismock.NewClientMock()
+
+	sqlite.Register(func(api *sqlite.ExtensionApi) (sqlite.ErrorCode, error) {
+		if err := api.CreateFunction("hexists", hexists.New(rdb)); err != nil {
+			return sqlite.SQLITE_ERROR, err
+		}
+		return sqlite.SQLITE_OK, nil
+	})
+
+	mock.ExpectHExists("mykey", "myfield").SetVal(true)
+	db, err := sqlx.Open("sqlite3", ":memory:")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+
+	row := db.QueryRow("SELECT hexists('mykey','myfield')")
+	err = row.Err()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var s string
+	err = row.Scan(&s)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if err := mock.ExpectationsWereMet(); err != nil {
+		t.Error(err)
+	}
+}

pkg/ext/ext.go

@@ -16,6 +16,7 @@ import (
 	"github.com/augmentable-dev/reqlite/internal/redis/dbsize"
 	"github.com/augmentable-dev/reqlite/internal/redis/dump"
 	"github.com/augmentable-dev/reqlite/internal/redis/echo"
+	"github.com/augmentable-dev/reqlite/internal/redis/hexists"
 	"github.com/augmentable-dev/reqlite/internal/redis/hgetall"
 	"github.com/augmentable-dev/reqlite/internal/redis/llen"
 	"github.com/augmentable-dev/reqlite/internal/redis/lrange"
@@ -98,6 +99,10 @@ func init() {
 			return sqlite.SQLITE_ERROR, err
 		}
 
+		if err := api.CreateFunction("hexists", hexists.New(rdb)); err != nil {
+			return sqlite.SQLITE_ERROR, err
+		}
+
 		if err := api.CreateFunction("llen", llen.New(rdb)); err != nil {
 			return sqlite.SQLITE_ERROR, err
 		}