cli: fetch extended evet types from contract config

The user should specify it via parameter's `extendedtype` field and
via upper-level `namedtypes` field of the contract configuration YAML.

Also, as we have proper event structure source, make the `--guess-eventtype`
compilation option and make event types guess optional.

Signed-off-by: Anna Shaleva <shaleva.ann@nspcc.ru>

cli/smartcontract/smart_contract.go

@@ -24,6 +24,7 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/rpcclient/invoker"
 	"github.com/nspcc-dev/neo-go/pkg/rpcclient/management"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract"
+	"github.com/nspcc-dev/neo-go/pkg/smartcontract/binding"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract/manifest"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract/nef"
 	"github.com/nspcc-dev/neo-go/pkg/util"
@@ -125,7 +126,7 @@ func NewCommands() []cli.Command {
 			{
 				Name:      "compile",
 				Usage:     "compile a smart contract to a .nef file",
-				UsageText: "neo-go contract compile -i path [-o nef] [-v] [-d] [-m manifest] [-c yaml] [--bindings file] [--no-standards] [--no-events] [--no-permissions]",
+				UsageText: "neo-go contract compile -i path [-o nef] [-v] [-d] [-m manifest] [-c yaml] [--bindings file] [--no-standards] [--no-events] [--no-permissions] [--guess-eventtypes]",
 				Description: `Compiles given smart contract to a .nef file and emits other associated
    information (manifest, bindings configuration, debug information files) if
    asked to. If none of --out, --manifest, --config, --bindings flags are specified,
@@ -171,6 +172,10 @@ func NewCommands() []cli.Command {
 						Name:  "no-permissions",
 						Usage: "do not check if invoked contracts are allowed in manifest",
 					},
+					cli.BoolFlag{
+						Name:  "guess-eventtypes",
+						Usage: "guess event types for smart-contract bindings configuration from the code usages",
+					},
 					cli.StringFlag{
 						Name:  "bindings",
 						Usage: "output file for smart-contract bindings configuration",
@@ -352,13 +357,15 @@ func initSmartContract(ctx *cli.Context) error {
 		SourceURL:          "http://example.com/",
 		SupportedStandards: []string{},
 		SafeMethods:        []string{},
-		Events: []manifest.Event{
+		Events: []compiler.HybridEvent{
 			{
 				Name: "Hello world!",
-				Parameters: []manifest.Parameter{
+				Parameters: []compiler.HybridParameter{
 					{
-						Name: "args",
+						Parameter: manifest.Parameter{
-						Type: smartcontract.ArrayType,
+							Name: "args",
+							Type: smartcontract.ArrayType,
+						},
 					},
 				},
 			},
@@ -447,6 +454,8 @@ func contractCompile(ctx *cli.Context) error {
 		NoStandardCheck:    ctx.Bool("no-standards"),
 		NoEventsCheck:      ctx.Bool("no-events"),
 		NoPermissionsCheck: ctx.Bool("no-permissions"),
+
+		GuessEventTypes: ctx.Bool("guess-eventtypes"),
 	}
 
 	if len(confFile) != 0 {
@@ -457,6 +466,7 @@ func contractCompile(ctx *cli.Context) error {
 		o.Name = conf.Name
 		o.SourceURL = conf.SourceURL
 		o.ContractEvents = conf.Events
+		o.DeclaredNamedTypes = conf.NamedTypes
 		o.ContractSupportedStandards = conf.SupportedStandards
 		o.Permissions = make([]manifest.Permission, len(conf.Permissions))
 		for i := range conf.Permissions {
@@ -705,9 +715,10 @@ type ProjectConfig struct {
 	SourceURL          string
 	SafeMethods        []string
 	SupportedStandards []string
-	Events             []manifest.Event
+	Events             []compiler.HybridEvent
 	Permissions        []permission
-	Overloads          map[string]string `yaml:"overloads,omitempty"`
+	Overloads          map[string]string               `yaml:"overloads,omitempty"`
+	NamedTypes         map[string]binding.ExtendedType `yaml:"namedtypes,omitempty"`
 }
 
 func inspect(ctx *cli.Context) error {

docs/compiler.md

@@ -472,10 +472,113 @@ and structures. Notice that structured types returned by methods can't be Null
 at the moment (see #2795).
 
 ```
-$ ./bin/neo-go contract compile -i contract.go --config contract.yml -o contract.nef --manifest manifest.json --bindings contract.bindings.yml
+$ ./bin/neo-go contract compile -i contract.go --config contract.yml -o contract.nef --manifest manifest.json --bindings contract.bindings.yml --guess-eventtypes
 $ ./bin/neo-go contract generate-rpcwrapper --manifest manifest.json --config contract.bindings.yml --out rpcwrapper.go --hash 0x1b4357bff5a01bdf2a6581247cf9ed1e24629176
 ```
 
+Contract-specific RPC-bindings generated by "generate-rpcwrapper" command include
+structure wrappers for each event declared in the contract manifest as far as the
+set of helpers that allow to retrieve emitted event from the application log or
+from stackitem. By default, event wrappers builder use event structure that was
+described in the manifest. Since the type data available in the manifest is
+limited, in some cases the resulting generated event structure may use generic
+go types. Go contracts can make use of additional type data from bindings
+configuration file generated during compilation. Like for any other contract
+types, this can cover arrays, maps and structures. To reach the maximum
+resemblance between the emitted events and the generated event wrappers, we
+recommend either to fill in the extended events type information in the contract
+configuration file before the compilation or to use `--guess-eventtypes`
+compilation option.
+
+If using `--guess-eventtypes` compilation option, event parameter types will be
+guessed from the arguments of `runtime.Notify` calls for each emitted event. If
+multiple calls of `runtime.Notify` are found, then argument types will be checked
+for matching (guessed types must be the same across the particular event usages).
+After that, the extended types binding configuration will be generated according
+to the emitted events parameter types. `--guess-eventtypes` compilation option
+is able to recognize those events that has a constant name known at a compilation
+time and do not include variadic arguments usage. Thus, use this option if your
+contract suites these requirements. Otherwise, we recommend to manually specify
+extended event parameter types information in the contract configuration file.
+
+Extended event parameter type information can be provided manually via contract
+configuration file under the `events` section. Each event parameter specified in
+this section may be supplied with additional parameter type information specified
+under `extendedtype` subsection. The extended type information (`ExtendedType`)
+has the following structure:
+
+| Field       | Type                                                                                                                                  | Required                                                                             | Meaning                                                                                                                                          |
+|-------------|---------------------------------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------|
+| `base`      | Any valid [NEP-14 parameter type](https://github.com/neo-project/proposals/blob/master/nep-14.mediawiki#parametertype) except `Void`. | Always required.                                                                              | The base type of a parameter, e.g. `Array` for go structures and any nested arrays, `Map` for nested maps, `Hash160` for 160-bits integers, etc. |
+| `name`      | `string`                                                                                                                              | Required for structures, omitted for arrays, interfaces and maps.                    | Name of a structure that will be used in the resulting RPC binding.                                                                              |
+| `interface` | `string`                                                                                                                              | Required for `InteropInterface`-based types, currently `iterator` only is supported. | Underlying value of the `InteropInterface`.                                                                                                      |
+| `key`       | Any simple [NEP-14 parameter type](https://github.com/neo-project/proposals/blob/master/nep-14.mediawiki#parametertype).              | Required for `Map`-based types.                                                      | Key type for maps.                                                                                                                               |
+| `value`     | `ExtendedType`.                                                        | Required for iterators, arrays and maps.                                             | Value type of iterators, arrays and maps.                                                                                                        |
+| `fields`    | Array of `FieldExtendedType`.                                                                                                         | Required for structures.                                                             | Ordered type data for structure fields.                                                                                                          |
+
+The structure's field extended information (`FieldExtendedType`) has the following structure:
+
+| Field                  | Type           | Required         | Meaning                                                                     |
+|------------------------|----------------|------------------|-----------------------------------------------------------------------------|
+| `field`                | `string`       | Always required. | Name of the structure field that will be used in the resulting RPC binding. |
+| Inlined `ExtendedType` | `ExtendedType` | Always required. | The extended type information about structure field.                        |
+
+
+Any named structures used in the `ExtendedType` description must be manually
+specified in the contract configuration file under top-level `namedtypes` section
+in the form of `map[string]ExtendedType`, where the map key is a name of the
+described named structure that matches the one provided in the `name` field of
+the event parameter's extended type.
+
+Here's the example of manually-created contract configuration file that uses
+extended types for event parameters description:
+
+```
+name: "HelloWorld contract"
+supportedstandards: []
+events:
+  - name: Some simple notification
+    parameters:
+      - name: intP
+        type: Integer
+      - name: boolP
+        type: Boolean
+      - name: stringP
+        type: String
+  - name: Structure notification
+    parameters:
+      - name: structure parameter
+        type: Array
+        extendedtype:
+          base: Array
+          name: transferData
+  - name: Map of structures notification
+    parameters:
+      - name: map parameter
+        type: Map
+        extendedtype:
+          base: Map
+          key: Integer
+          value:
+            base: Array
+            name: transferData
+  - name: Iterator notification
+    parameters:
+      - name: data
+        type: InteropInterface
+        extendedtype:
+          base: InteropInterface
+          interface: iterator
+namedtypes:
+  transferData:
+    base: Array
+    fields:
+      - field: IntField
+        base: Integer
+      - field: BoolField
+        base: Boolean
+```
+
 ## Smart contract examples
 
 Some examples are provided in the [examples directory](../examples). For more

internal/testchain/transaction.go

@@ -76,6 +76,7 @@ func NewDeployTx(bc Ledger, name string, sender util.Uint160, r gio.Reader, conf
 		o.Name = conf.Name
 		o.SourceURL = conf.SourceURL
 		o.ContractEvents = conf.Events
+		o.DeclaredNamedTypes = conf.NamedTypes
 		o.ContractSupportedStandards = conf.SupportedStandards
 		o.Permissions = make([]manifest.Permission, len(conf.Permissions))
 		for i := range conf.Permissions {

pkg/compiler/compiler.go

@@ -52,14 +52,26 @@ type Options struct {
 	// This setting has effect only if manifest is emitted.
 	NoPermissionsCheck bool
 
+	// GuessEventTypes specifies if types of runtime notifications need to be guessed
+	// from the usage context. These types are used for RPC binding generation only and
+	// can be defined for events with name known at the compilation time and without
+	// variadic args usages. If some type is specified via config file, then the config's
+	// one is preferable. Currently, event's parameter type is defined from the first
+	// occurrence of event call.
+	GuessEventTypes bool
+
 	// Name is a contract's name to be written to manifest.
 	Name string
 
 	// SourceURL is a contract's source URL to be written to manifest.
 	SourceURL string
 
-	// Runtime notifications.
+	// Runtime notifications declared in the contract configuration file.
-	ContractEvents []manifest.Event
+	ContractEvents []HybridEvent
+
+	// DeclaredNamedTypes is the set of named types that were declared in the
+	// contract configuration type and are the part of manifest events.
+	DeclaredNamedTypes map[string]binding.ExtendedType
 
 	// The list of standards supported by the contract.
 	ContractSupportedStandards []string
@@ -78,6 +90,23 @@ type Options struct {
 	BindingsFile string
 }
 
+// HybridEvent represents the description of event emitted by the contract squashed
+// with extended event's parameters description. We have it as a separate type for
+// the user's convenience. It is applied for the smart contract configuration file
+// only.
+type HybridEvent struct {
+	Name       string            `json:"name"`
+	Parameters []HybridParameter `json:"parameters"`
+}
+
+// HybridParameter contains the manifest's event parameter description united with
+// the extended type description for this parameter. It is applied for the smart
+// contract configuration file only.
+type HybridParameter struct {
+	manifest.Parameter `yaml:",inline"`
+	ExtendedType       *binding.ExtendedType `yaml:"extendedtype,omitempty"`
+}
+
 type buildInfo struct {
 	config  *packages.Config
 	program []*packages.Package
@@ -309,18 +338,42 @@ func CompileAndSave(src string, o *Options) ([]byte, error) {
 		if len(di.NamedTypes) > 0 {
 			cfg.NamedTypes = di.NamedTypes
 		}
-		if len(di.EmittedEvents) > 0 {
+		for name, et := range o.DeclaredNamedTypes {
-			for eventName, eventUsages := range di.EmittedEvents {
+			// TODO: handle name conflict
-				for typeName, extType := range eventUsages[0].ExtTypes {
+			cfg.NamedTypes[name] = et
-					cfg.NamedTypes[typeName] = extType
+		}
+		for _, e := range o.ContractEvents {
+			for _, p := range e.Parameters {
+				// TODO: proper imports handling during bindings generation (see utf8 example).
+				if p.ExtendedType != nil {
+					pName := e.Name + "." + p.Name
+					cfg.Types[pName] = *p.ExtendedType
 				}
-				for _, p := range eventUsages[0].Params {
+			}
-					pname := eventName + "." + p.Name
+		}
-					if p.RealType.TypeName != "" {
+		if o.GuessEventTypes {
-						cfg.Overrides[pname] = p.RealType
+			if len(di.EmittedEvents) > 0 {
+				for eventName, eventUsages := range di.EmittedEvents {
+					// Take into account the first usage only.
+					// TODO: extend it to the rest of invocations.
+					for typeName, extType := range eventUsages[0].ExtTypes {
+						if _, ok := cfg.NamedTypes[typeName]; !ok {
+							cfg.NamedTypes[typeName] = extType
+						}
 					}
-					if p.ExtendedType != nil {
+					for _, p := range eventUsages[0].Params {
-						cfg.Types[pname] = *p.ExtendedType
+						// TODO: prettify notification name in-place.
+						pname := eventName + "." + p.Name
+						if p.RealType.TypeName != "" {
+							if _, ok := cfg.Overrides[pname]; !ok {
+								cfg.Overrides[pname] = p.RealType
+							}
+						}
+						if p.ExtendedType != nil {
+							if _, ok := cfg.Types[pname]; !ok {
+								cfg.Types[pname] = *p.ExtendedType
+							}
+						}
 					}
 				}
 			}

pkg/compiler/compiler_test.go

@@ -159,16 +159,16 @@ func TestEventWarnings(t *testing.T) {
 	})
 	t.Run("wrong parameter number", func(t *testing.T) {
 		_, err = compiler.CreateManifest(di, &compiler.Options{
-			ContractEvents: []manifest.Event{{Name: "Event"}},
+			ContractEvents: []compiler.HybridEvent{{Name: "Event"}},
 			Name:           "payable",
 		})
 		require.Error(t, err)
 	})
 	t.Run("wrong parameter type", func(t *testing.T) {
 		_, err = compiler.CreateManifest(di, &compiler.Options{
-			ContractEvents: []manifest.Event{{
+			ContractEvents: []compiler.HybridEvent{{
 				Name:       "Event",
-				Parameters: []manifest.Parameter{manifest.NewParameter("number", smartcontract.StringType)},
+				Parameters: []compiler.HybridParameter{{Parameter: manifest.NewParameter("number", smartcontract.StringType)}},
 			}},
 			Name: "payable",
 		})
@@ -176,9 +176,9 @@ func TestEventWarnings(t *testing.T) {
 	})
 	t.Run("any parameter type", func(t *testing.T) {
 		_, err = compiler.CreateManifest(di, &compiler.Options{
-			ContractEvents: []manifest.Event{{
+			ContractEvents: []compiler.HybridEvent{{
 				Name:       "Event",
-				Parameters: []manifest.Parameter{manifest.NewParameter("number", smartcontract.AnyType)},
+				Parameters: []compiler.HybridParameter{{Parameter: manifest.NewParameter("number", smartcontract.AnyType)}},
 			}},
 			Name: "payable",
 		})
@@ -186,9 +186,9 @@ func TestEventWarnings(t *testing.T) {
 	})
 	t.Run("good", func(t *testing.T) {
 		_, err = compiler.CreateManifest(di, &compiler.Options{
-			ContractEvents: []manifest.Event{{
+			ContractEvents: []compiler.HybridEvent{{
 				Name:       "Event",
-				Parameters: []manifest.Parameter{manifest.NewParameter("number", smartcontract.IntegerType)},
+				Parameters: []compiler.HybridParameter{{Parameter: manifest.NewParameter("number", smartcontract.IntegerType)}},
 			}},
 			Name: "payable",
 		})
@@ -224,7 +224,7 @@ func TestEventWarnings(t *testing.T) {
 			require.Error(t, err)
 
 			_, err = compiler.CreateManifest(di, &compiler.Options{
-				ContractEvents: []manifest.Event{{Name: "Event"}},
+				ContractEvents: []compiler.HybridEvent{{Name: "Event"}},
 				Name:           "eventTest",
 			})
 			require.NoError(t, err)
@@ -242,9 +242,9 @@ func TestEventWarnings(t *testing.T) {
 
 		_, err = compiler.CreateManifest(di, &compiler.Options{
 			Name: "eventTest",
-			ContractEvents: []manifest.Event{{
+			ContractEvents: []compiler.HybridEvent{{
 				Name:       "Event",
-				Parameters: []manifest.Parameter{manifest.NewParameter("number", smartcontract.IntegerType)},
+				Parameters: []compiler.HybridParameter{{Parameter: manifest.NewParameter("number", smartcontract.IntegerType)}},
 			}},
 		})
 		require.NoError(t, err)
@@ -260,7 +260,7 @@ func TestNotifyInVerify(t *testing.T) {
 		t.Run(name, func(t *testing.T) {
 			src := fmt.Sprintf(srcTmpl, name)
 			_, _, err := compiler.CompileWithOptions("eventTest.go", strings.NewReader(src),
-				&compiler.Options{ContractEvents: []manifest.Event{{Name: "Event"}}})
+				&compiler.Options{ContractEvents: []compiler.HybridEvent{{Name: "Event"}}})
 			require.Error(t, err)
 
 			t.Run("suppress", func(t *testing.T) {

pkg/compiler/debug.go

@@ -593,9 +593,20 @@ func (di *DebugInfo) ConvertToManifest(o *Options) (*manifest.Manifest, error) {
 	if o.ContractSupportedStandards != nil {
 		result.SupportedStandards = o.ContractSupportedStandards
 	}
+	events := make([]manifest.Event, len(o.ContractEvents))
+	for i, e := range o.ContractEvents {
+		params := make([]manifest.Parameter, len(e.Parameters))
+		for j, p := range e.Parameters {
+			params[j] = p.Parameter
+		}
+		events[i] = manifest.Event{
+			Name:       o.ContractEvents[i].Name,
+			Parameters: params,
+		}
+	}
 	result.ABI = manifest.ABI{
 		Methods: methods,
-		Events:  o.ContractEvents,
+		Events:  events,
 	}
 	if result.ABI.Events == nil {
 		result.ABI.Events = make([]manifest.Event, 0)

pkg/compiler/interop_test.go

@@ -542,13 +542,13 @@ func TestForcedNotifyArgumentsConversion(t *testing.T) {
 		if count != len(expectedVMParamTypes) {
 			t.Fatalf("parameters count mismatch: %d vs %d", count, len(expectedVMParamTypes))
 		}
-		scParams := make([]manifest.Parameter, len(targetSCParamTypes))
+		scParams := make([]compiler.HybridParameter, len(targetSCParamTypes))
 		vmParams := make([]stackitem.Item, len(expectedVMParamTypes))
 		for i := range scParams {
-			scParams[i] = manifest.Parameter{
+			scParams[i] = compiler.HybridParameter{Parameter: manifest.Parameter{
 				Name: strconv.Itoa(i),
 				Type: targetSCParamTypes[i],
-			}
+			}}
 			defaultValue := stackitem.NewBigInteger(big.NewInt(int64(i)))
 			var (
 				val stackitem.Item
@@ -564,7 +564,7 @@ func TestForcedNotifyArgumentsConversion(t *testing.T) {
 		}
 		ctr := neotest.CompileSource(t, e.CommitteeHash, strings.NewReader(src), &compiler.Options{
 			Name: "Helper",
-			ContractEvents: []manifest.Event{
+			ContractEvents: []compiler.HybridEvent{
 				{
 					Name:       methodWithoutEllipsis,
 					Parameters: scParams,

pkg/neotest/compile.go

@@ -60,6 +60,7 @@ func CompileFile(t testing.TB, sender util.Uint160, srcPath string, configPath s
 	o := &compiler.Options{}
 	o.Name = conf.Name
 	o.ContractEvents = conf.Events
+	o.DeclaredNamedTypes = conf.NamedTypes
 	o.ContractSupportedStandards = conf.SupportedStandards
 	o.Permissions = make([]manifest.Permission, len(conf.Permissions))
 	for i := range conf.Permissions {