Add basic auto-completion support (#4)

go.mod

@@ -3,22 +3,23 @@ module github.com/sneller-inc/sneller
 go 1.19
 
 require (
+	github.com/SnellerInc/sneller v0.0.0-20230505151417-5806cd3a42c7
 	github.com/grafana/grafana-plugin-sdk-go v0.159.0
+	github.com/patrickmn/go-cache v2.1.0+incompatible
 	go.opentelemetry.io/otel v1.14.0
 	go.opentelemetry.io/otel/trace v1.14.0
+	golang.org/x/exp v0.0.0-20230425010034-47ecfdc1ba53
 )
 
 require (
 	github.com/BurntSushi/toml v1.2.1 // indirect
-	github.com/SnellerInc/sneller v0.0.0-20230505151417-5806cd3a42c7 // indirect
 	github.com/apache/arrow/go/arrow v0.0.0-20211112161151-bc219186db40 // indirect
 	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/cenkalti/backoff/v4 v4.2.0 // indirect
 	github.com/cespare/xxhash/v2 v2.2.0 // indirect
 	github.com/cheekybits/genny v1.0.0 // indirect
 	github.com/chromedp/cdproto v0.0.0-20220208224320-6efb837e6bc2 // indirect
 	github.com/cpuguy83/go-md2man/v2 v2.0.2 // indirect
-	github.com/dchest/siphash v1.2.3 // indirect
 	github.com/elazarl/goproxy v0.0.0-20220115173737-adb46da277ac // indirect
 	github.com/fatih/color v1.7.0 // indirect
 	github.com/getkin/kin-openapi v0.112.0 // indirect
@@ -73,8 +74,6 @@ require (
 	go.opentelemetry.io/otel/metric v0.37.0 // indirect
 	go.opentelemetry.io/otel/sdk v1.14.0 // indirect
 	go.opentelemetry.io/proto/otlp v0.19.0 // indirect
-	golang.org/x/crypto v0.8.0 // indirect
-	golang.org/x/exp v0.0.0-20230425010034-47ecfdc1ba53 // indirect
 	golang.org/x/net v0.9.0 // indirect
 	golang.org/x/sys v0.7.0 // indirect
 	golang.org/x/text v0.9.0 // indirect

go.sum

@@ -43,8 +43,6 @@ github.com/OneOfOne/xxhash v1.2.2/go.mod h1:HSdplMjZKSmBqAxg5vPj2TmRDmfkzw+cTzAE
 github.com/SnellerInc/sneller v0.0.0-20230505151417-5806cd3a42c7 h1:3GAYAlEQoiW3q8x88cbi140EM1p3g8vBHxqWS75Oro8=
 github.com/SnellerInc/sneller v0.0.0-20230505151417-5806cd3a42c7/go.mod h1:BaisUxgu4MI9tL6dwYPccGKsXkBP7+BnMz8fL/F/TNk=
 github.com/ajstarks/svgo v0.0.0-20180226025133-644b8db467af/go.mod h1:K08gAheRH3/J6wwsYMMT4xOr94bZjxIelGM0+d/wbFw=
-github.com/amazon-ion/ion-go v1.2.0 h1:EgFy23/7gRxRYdUkJARh/7eZc8BYkFFDZZSqB3PwVqQ=
-github.com/amazon-ion/ion-go v1.2.0/go.mod h1:3ZEje8i20TiIPVZlN+KE3B2ppZ1B8d9F/KaT7Dtec+k=
 github.com/antihax/optional v1.0.0/go.mod h1:uupD/76wgC+ih3iEmQUL+0Ugr19nfwCT1kdvxnR2qWY=
 github.com/apache/arrow/go/arrow v0.0.0-20211112161151-bc219186db40 h1:q4dksr6ICHXqG5hm0ZW5IHyeEJXoIJSOZeBLmWPNeIQ=
 github.com/apache/arrow/go/arrow v0.0.0-20211112161151-bc219186db40/go.mod h1:Q7yQnSMnLvcXlZ8RV+jwz/6y1rQTqbX6C82SndT52Zs=
@@ -83,7 +81,6 @@ github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSs
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/dchest/siphash v1.2.3 h1:QXwFc8cFOR2dSa/gE6o/HokBMWtLUaNDVd+22aKHeEA=
-github.com/dchest/siphash v1.2.3/go.mod h1:0NvQU092bT0ipiFN++/rXm69QG9tVxLAlQHIXMPAkHc=
 github.com/elazarl/goproxy v0.0.0-20220115173737-adb46da277ac h1:XDAn206aIqKPdF5YczuuJXSQPx+WOen0Pxbxp5Fq8Pg=
 github.com/elazarl/goproxy v0.0.0-20220115173737-adb46da277ac/go.mod h1:Ro8st/ElPeALwNFlcTpWmkr6IoMFfkjXAvTHpevnDsM=
 github.com/elazarl/goproxy/ext v0.0.0-20190711103511-473e67f1d7d2/go.mod h1:gNh8nYJoAm43RfaxurUnxr+N1PwuFV3ZMl/efxlIlY8=
@@ -274,6 +271,8 @@ github.com/oklog/run v1.0.0/go.mod h1:dlhp/R75TPv97u0XWUtDeV/lRKWPKSdTuV0TZvrmrQ
 github.com/olekukonko/tablewriter v0.0.5 h1:P2Ga83D34wi1o9J6Wh1mRuqd4mF/x/lgBS7N7AbDhec=
 github.com/olekukonko/tablewriter v0.0.5/go.mod h1:hPp6KlRPjbx+hW8ykQs1w3UBbZlj6HuIJcUGPhkA7kY=
 github.com/opentracing/opentracing-go v1.1.0/go.mod h1:UkNAQd3GIcIGf0SeVgPpRdFStlNbqXla1AfSYxPUl2o=
+github.com/patrickmn/go-cache v2.1.0+incompatible h1:HRMgzkcYKYpi3C8ajMPV8OFXaaRUnok+kx1WdO15EQc=
+github.com/patrickmn/go-cache v2.1.0+incompatible/go.mod h1:3Qf8kWWT7OJRJbdiICTKqZju1ZixQ/KpMGzzAfe6+WQ=
 github.com/phpdave11/gofpdf v1.4.2/go.mod h1:zpO6xFn9yxo3YLyMvW8HcKWVdbNqgIfOOp2dXMnm1mY=
 github.com/phpdave11/gofpdi v1.0.12/go.mod h1:vBmVV0Do6hSBHC8uKUQ71JGW+ZGQq74llk/7bXwjDoI=
 github.com/pierrec/lz4/v4 v4.1.8 h1:ieHkV+i2BRzngO4Wd/3HGowuZStgq6QkPsD1eolNAO4=
@@ -372,7 +371,6 @@ golang.org/x/crypto v0.0.0-20190605123033-f99c8df09eb5/go.mod h1:yigFU9vqHzYiE8U
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/crypto v0.8.0 h1:pd9TJtTueMTVQXzk8E2XESSMQDj/U7OUu0PqJqPXQjQ=
-golang.org/x/crypto v0.8.0/go.mod h1:mRqEX+O9/h5TFCrQhkgjo2yKi0yYA+9ecGkdQoHrywE=
 golang.org/x/exp v0.0.0-20180321215751-8460e604b9de/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/exp v0.0.0-20180807140117-3d87b88a115f/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/exp v0.0.0-20190121172915-509febef88a4/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=

package.json

@@ -46,8 +46,8 @@
     "sass-loader": "13.2.0",
     "style-loader": "3.3.1",
     "swc-loader": "^0.2.3",
-    "tsconfig-paths": "^4.1.0",
     "ts-node": "^10.5.0",
+    "tsconfig-paths": "^4.1.0",
     "typescript": "^4.4.0",
     "webpack": "^5.69.1",
     "webpack-cli": "^4.9.2",
@@ -59,6 +59,7 @@
   "dependencies": {
     "@emotion/css": "^11.1.3",
     "@grafana/data": "9.3.8",
+    "@grafana/experimental": "^1.1.0",
     "@grafana/runtime": "9.3.8",
     "@grafana/ui": "9.3.8",
     "react": "17.0.2",

pkg/plugin/api.go

@@ -8,8 +8,11 @@ import (
 	"io"
 	"net/http"
 	"strings"
+	"time"
 
+	"github.com/SnellerInc/sneller/ion"
 	"github.com/grafana/grafana-plugin-sdk-go/backend/log"
+	"golang.org/x/exp/maps"
 )
 
 // executeQuery executes a Sneller query and returns the HTTP response.
@@ -21,6 +24,12 @@ func (d *Datasource) executeQuery(ctx context.Context, database, sql string) (*h
 
 // getDatabases returns a list of database names.
 func (d *Datasource) getDatabases(ctx context.Context) ([]string, int, error) {
+	key := "databases"
+	cached, found := d.cache.Get(key)
+	if found {
+		return cached.([]string), 0, nil
+	}
+
 	resp, err := d.executeRequest(ctx, http.MethodGet, "/databases", nil,
 		map[string]string{"Accept": "application/json"},
 		nil)
@@ -48,11 +57,19 @@ func (d *Datasource) getDatabases(ctx context.Context) ([]string, int, error) {
 		return t.Name
 	})
 
+	d.cache.Set(key, names, time.Minute*1)
+
 	return names, 0, nil
 }
 
 // getTables returns a list of table names for the given database.
 func (d *Datasource) getTables(ctx context.Context, database string) ([]string, int, error) {
+	key := fmt.Sprintf("tables_%s", database)
+	cached, found := d.cache.Get(key)
+	if found {
+		return cached.([]string), 0, nil
+	}
+
 	resp, err := d.executeRequest(ctx, http.MethodGet, "/tables", nil,
 		map[string]string{"Accept": "application/json"},
 		map[string]string{"database": database})
@@ -76,9 +93,57 @@ func (d *Datasource) getTables(ctx context.Context, database string) ([]string,
 		return nil, 500, err
 	}
 
+	d.cache.Set(key, result, time.Minute*1)
+
 	return result, 0, nil
 }
 
+// getColumns returns a list of column names for the given database and table.
+func (d *Datasource) getColumns(ctx context.Context, database, table string) ([]string, int, error) {
+	key := fmt.Sprintf("columns_%s_%s", database, table)
+	cached, found := d.cache.Get(key)
+	if found {
+		return cached.([]string), 0, nil
+	}
+
+	resp, err := d.executeQuery(ctx, database, fmt.Sprintf(`SELECT SNELLER_DATASHAPE(*) FROM (SELECT * FROM %q LIMIT 1000)`, table))
+	if err != nil {
+		if resp != nil {
+			return nil, resp.StatusCode, err
+		}
+		return nil, 500, err
+	}
+
+	defer func() {
+		if err := resp.Body.Close(); err != nil {
+			log.DefaultLogger.Error("failed to close response body", "err", err)
+		}
+	}()
+
+	payload := map[string]any{}
+
+	err = ion.NewDecoder(resp.Body, 1024*1024*10).Decode(&payload)
+	if err != nil {
+		return nil, 500, err
+	}
+
+	fields, ok := payload["fields"]
+	if !ok {
+		return []string{}, 0, nil
+	}
+
+	vals, ok := fields.(map[string]any)
+	if !ok {
+		return []string{}, 0, nil
+	}
+
+	cols := maps.Keys(vals)
+
+	d.cache.Set(key, cols, time.Minute*1)
+
+	return cols, 0, nil
+}
+
 // newRequest creates a new HTTP request and initializes the 'Authentication' header from the
 // configured Sneller authentication token in the 'Authentication' header.
 func (d *Datasource) newRequest(ctx context.Context, method, path string, body io.Reader) (*http.Request, error) {

pkg/plugin/datasource.go

@@ -18,6 +18,7 @@ import (
 	"github.com/grafana/grafana-plugin-sdk-go/backend/log"
 	"github.com/grafana/grafana-plugin-sdk-go/backend/tracing"
 	"github.com/grafana/grafana-plugin-sdk-go/data"
+	cache "github.com/patrickmn/go-cache"
 	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/trace"
 )
@@ -58,6 +59,7 @@ func NewDatasource(settings backend.DataSourceInstanceSettings) (instancemgmt.In
 		settings: settings,
 		endpoint: jsonData.Endpoint,
 		client:   client,
+		cache:    cache.New(5*time.Minute, 5*time.Minute),
 	}
 
 	mux := datasource.NewQueryTypeMux()
@@ -76,6 +78,7 @@ type Datasource struct {
 	handler  backend.QueryDataHandler
 	endpoint string
 	client   *http.Client
+	cache    *cache.Cache
 }
 
 // Dispose here tells plugin SDK that plugin wants to clean up resources when a new instance
@@ -154,6 +157,13 @@ func (d *Datasource) CallResource(ctx context.Context, req *backend.CallResource
 			})
 		}
 		return sender.Send(d.handleCallResourceTables(ctx, segments[1]))
+	case "columns":
+		if len(segments) != 3 {
+			return sender.Send(&backend.CallResourceResponse{
+				Status: http.StatusBadRequest,
+			})
+		}
+		return sender.Send(d.handleCallResourceColumns(ctx, segments[1], segments[2]))
 	default:
 		return sender.Send(&backend.CallResourceResponse{
 			Status: http.StatusNotFound,
@@ -203,6 +213,27 @@ func (d *Datasource) handleCallResourceTables(ctx context.Context, database stri
 	}
 }
 
+func (d *Datasource) handleCallResourceColumns(ctx context.Context, database, table string) *backend.CallResourceResponse {
+	databases, status, err := d.getColumns(ctx, database, table)
+	if err != nil {
+		return &backend.CallResourceResponse{
+			Status: status,
+			Body:   []byte(err.Error()),
+		}
+	}
+	result, err := json.Marshal(databases)
+	if err != nil {
+		return &backend.CallResourceResponse{
+			Status: status,
+			Body:   []byte(err.Error()),
+		}
+	}
+	return &backend.CallResourceResponse{
+		Status: http.StatusOK,
+		Body:   result,
+	}
+}
+
 func (d *Datasource) handleQuery(ctx context.Context, req *backend.QueryDataRequest) (*backend.QueryDataResponse, error) {
 	response := backend.NewQueryDataResponse()
 
@@ -274,6 +305,8 @@ func (d *Datasource) query(ctx context.Context, _ backend.PluginContext, query b
 			switch resp.StatusCode {
 			case http.StatusUnauthorized:
 				return backend.ErrDataResponse(backend.StatusUnauthorized, fmt.Sprintf("unauthorized: %s", err))
+			case http.StatusForbidden:
+				return backend.ErrDataResponse(backend.StatusForbidden, fmt.Sprintf("forbidden: %s", err))
 			case http.StatusBadRequest:
 				return backend.ErrDataResponse(backend.StatusValidationFailed, fmt.Sprintf("bad request: %s", err))
 			}