More features (#8)

- envs: add Env type and Devnet, Testnet, Mainnet default envs
- accounts: add JSON support for ProductAccount
- query: add Client.GetMappingAccount
- query: add Client.GetAllProductKeys
- query: add Client.GetAllProducts
- README: add attributions

Author: Richard Patel

README.md

@@ -7,7 +7,6 @@
     <a href="https://pkg.go.dev/go.blockdaemon.com/pyth"><img src="https://pkg.go.dev/badge/go.blockdaemon.com/pyth.svg" alt="Go Reference"></a>
     <a href="https://github.com/Blockdaemon/pyth-go/actions/workflows/test.yml"><img src="https://github.com/Blockdaemon/pyth-go/actions/workflows/test.yml/badge.svg" alt="unit tests"></a>
   </p>
-  <sub>Built with 👿 at <a href="https://blockdaemon.com">Blockdaemon</a></sub>
 </div>
 
 ### Summary
@@ -27,3 +26,8 @@ go get go.blockdaemon.com/pyth@latest
 ```
 
 Find docs and usage examples on [pkg.go.dev](https://pkg.go.dev/go.blockdaemon.com/pyth).
+
+### Attributions
+
+- Built with 👿 at [Blockdaemon](https://blockdaemon.com)
+- Using [immaterial.ink's](https://twitter.com/immaterial_ink) awesome Solana [Go SDK](https://github.com/gagliardetto/solana-go)

accounts.go

@@ -15,7 +15,9 @@
 package pyth
 
 import (
+	"encoding/json"
 	"errors"
+	"fmt"
 
 	bin "github.com/gagliardetto/binary"
 	"github.com/gagliardetto/solana-go"
@@ -67,6 +69,9 @@ type ProductAccount struct {
 	AttrsData  [464]byte        // key-value string pairs of additional data
 }
 
+// ProductAccountAttrsDataOffset is the binary offset of the AttrsData field within ProductAccount.
+const ProductAccountAttrsDataOffset = 48
+
 // UnmarshalBinary decodes the product account from the on-chain format.
 func (p *ProductAccount) UnmarshalBinary(buf []byte) error {
 	decoder := bin.NewBinDecoder(buf)
@@ -86,7 +91,7 @@ func (p *ProductAccount) UnmarshalBinary(buf []byte) error {
 func (p *ProductAccount) GetAttrsMap() (AttrsMap, error) {
 	// Length of attrs is determined by size value in header.
 	data := p.AttrsData[:]
-	maxSize := int(p.Size) - 48
+	maxSize := int(p.Size) - ProductAccountAttrsDataOffset
 	if maxSize > 0 && len(data) > maxSize {
 		data = data[:maxSize]
 	}
@@ -96,6 +101,50 @@ func (p *ProductAccount) GetAttrsMap() (AttrsMap, error) {
 	return attrs, err
 }
 
+// UnmarshalJSON loads the product account's content from JSON.
+func (p *ProductAccount) UnmarshalJSON(data []byte) error {
+	// Decode JSON as strings map.
+	var content map[string]string
+	if err := json.Unmarshal(data, &content); err != nil {
+		return err
+	}
+	// Re-encode as binary data.
+	attrsMap, err := NewAttrsMap(content)
+	if err != nil {
+		return err
+	}
+	mapData, err := attrsMap.MarshalBinary()
+	if err != nil {
+		return err // unreachable
+	}
+	if len(mapData) > len(p.AttrsData) {
+		return fmt.Errorf("data does not fit in product account")
+	}
+	// Copy binary data into product account, zero remaining bytes.
+	p.AccountHeader = AccountHeader{
+		Magic:       Magic,
+		Version:     V2,
+		AccountType: AccountTypeProduct,
+		Size:        uint32(ProductAccountAttrsDataOffset + len(mapData)),
+	}
+	copy(p.AttrsData[:], mapData)
+	for i := len(mapData); i < len(p.AttrsData); i++ {
+		p.AttrsData[i] = 0
+	}
+	return nil
+}
+
+// MarshalJSON returns a JSON-representation of the product account contents.
+func (p *ProductAccount) MarshalJSON() ([]byte, error) {
+	// Decode binary data from product account.
+	content, err := p.GetAttrsMap()
+	if err != nil {
+		return nil, err
+	}
+	// Re-encode as JSON.
+	return json.Marshal(content.KVs())
+}
+
 // Ema is an exponentially-weighted moving average.
 type Ema struct {
 	Val   int64
@@ -179,9 +228,9 @@ func (p *PriceAccount) GetComponent(publisher *solana.PublicKey) *PriceComp {
 // MappingAccount is a piece of a singly linked-list of all products on Pyth.
 type MappingAccount struct {
 	AccountHeader
-	Num      uint32
-	Unused   uint32
-	Next     solana.PublicKey
+	Num      uint32           // number of keys
+	Pad1     uint32           // reserved field
+	Next     solana.PublicKey // pubkey of next mapping account
 	Products [640]solana.PublicKey
 }
 
@@ -199,3 +248,11 @@ func (m *MappingAccount) UnmarshalBinary(buf []byte) error {
 	}
 	return nil
 }
+
+// ProductKeys returns the slice of product keys referenced by this mapping, excluding empty entries.
+func (m *MappingAccount) ProductKeys() []solana.PublicKey {
+	if m.Num > uint32(len(m.Products)) {
+		return nil
+	}
+	return m.Products[:m.Num]
+}

accounts_test.go

@@ -16,6 +16,7 @@ package pyth
 
 import (
 	_ "embed"
+	"encoding/json"
 	"testing"
 
 	"github.com/gagliardetto/solana-go"
@@ -67,20 +68,50 @@ func TestProductAccount(t *testing.T) {
 	require.NoError(t, actual.UnmarshalBinary(caseProductAccount))
 	assert.Equal(t, &productAccount_EWxGfxoPQSNA2744AYdAKmsQZ8F9o9M7oKkvL3VM1dko, &actual)
 
+	expectedMap := map[string]string{
+		"asset_type":     "FX",
+		"base":           "EUR",
+		"description":    "EUR/USD",
+		"generic_symbol": "EURUSD",
+		"quote_currency": "USD",
+		"symbol":         "FX.EUR/USD",
+		"tenor":          "Spot",
+	}
+
 	t.Run("GetAttrsMap", func(t *testing.T) {
-		expected := map[string]string{
-			"asset_type":     "FX",
-			"base":           "EUR",
-			"description":    "EUR/USD",
-			"generic_symbol": "EURUSD",
-			"quote_currency": "USD",
-			"symbol":         "FX.EUR/USD",
-			"tenor":          "Spot",
-		}
 		actualList, err := actual.GetAttrsMap()
 		assert.NoError(t, err)
 		actual := actualList.KVs()
-		assert.Equal(t, expected, actual)
+		assert.Equal(t, expectedMap, actual)
+	})
+
+	t.Run("JSON", func(t *testing.T) {
+		jsonData, err := json.Marshal(&actual)
+		require.NoError(t, err)
+
+		expected := `{
+			"asset_type": "FX",
+			"base": "EUR",
+			"description": "EUR/USD",
+			"generic_symbol": "EURUSD",
+			"quote_currency": "USD",
+			"symbol": "FX.EUR/USD",
+			"tenor": "Spot"
+		}`
+		assert.JSONEq(t, expected, string(jsonData))
+
+		// Deserialize JSON again.
+		var actual2 ProductAccount
+		// Write junk into target, so we can ensure the entire account is written.
+		for i := range actual2.AttrsData {
+			actual2.AttrsData[i] = 0x41
+		}
+		require.NoError(t, json.Unmarshal(jsonData, &actual2))
+		assert.True(t, actual2.Valid())
+		assert.Equal(t, actual.Size, actual2.Size)
+		actual2Map, err := actual2.GetAttrsMap()
+		require.NoError(t, err)
+		assert.Equal(t, expectedMap, actual2Map.KVs())
 	})
 }
 

client.go

@@ -15,7 +15,6 @@
 package pyth
 
 import (
-	"github.com/gagliardetto/solana-go"
 	"github.com/gagliardetto/solana-go/rpc"
 	"go.uber.org/zap"
 )
@@ -24,18 +23,22 @@ import (
 //
 // Do not instantiate Client directly, use NewClient instead.
 type Client struct {
-	ProgramKey   solana.PublicKey
+	Env          Env
 	RPC          *rpc.Client
 	WebSocketURL string
 	Log          *zap.Logger
+
+	AccountsBatchSize int // number of accounts to get with getMultipleAccounts()
 }
 
 // NewClient creates a new client to the Pyth on-chain program.
-func NewClient(programKey solana.PublicKey, rpcURL string, wsURL string) *Client {
+func NewClient(env Env, rpcURL string, wsURL string) *Client {
 	return &Client{
-		ProgramKey:   programKey,
+		Env:          env,
 		RPC:          rpc.New(rpcURL),
 		WebSocketURL: wsURL,
 		Log:          zap.NewNop(),
+
+		AccountsBatchSize: 32,
 	}
 }

cmd/pythian/main.go

@@ -0,0 +1 @@
+package pythian

envs.go

@@ -0,0 +1,41 @@
+//  Copyright 2022 Blockdaemon Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package pyth
+
+import "github.com/gagliardetto/solana-go"
+
+// Env identifies deployment of the Pyth on-chain program.
+type Env struct {
+	Program solana.PublicKey // Program ID
+	Mapping solana.PublicKey // Root mapping key
+}
+
+// Devnet is the Pyth program on the Solana devnet cluster.
+var Devnet = Env{
+	Program: solana.MustPublicKeyFromBase58("gSbePebfvPy7tRqimPoVecS2UsBvYv46ynrzWocc92s"),
+	Mapping: solana.MustPublicKeyFromBase58("BmA9Z6FjioHJPpjT39QazZyhDRUdZy2ezwx4GiDdE2u2"),
+}
+
+// Testnet is the Pyth program on the Solana testnet cluster.
+var Testnet = Env{
+	Program: solana.MustPublicKeyFromBase58("8tfDNiaEyrV6Q1U4DEXrEigs9DoDtkugzFbybENEbCDz"),
+	Mapping: solana.MustPublicKeyFromBase58("AFmdnt9ng1uVxqCmqwQJDAYC5cKTkw8gJKSM5PnzuF6z"),
+}
+
+// Mainnet is the Pyth program on the Solana mainnet cluster.
+var Mainnet = Env{
+	Program: solana.MustPublicKeyFromBase58("FsJ3A3u2vn5cTVofAjvy6y5kwABJAqYWpe4975bi2epH"),
+	Mapping: solana.MustPublicKeyFromBase58("AHtgzX45WTKfkPG53L6WYhGEXwQkN1BVknET3sVsLL8J"),
+}

instructions.go

@@ -23,24 +23,10 @@ import (
 	"github.com/gagliardetto/solana-go"
 )
 
-// Program IDs of the Pyth oracle program.
-var (
-	ProgramIDDevnet  = solana.MustPublicKeyFromBase58("gSbePebfvPy7tRqimPoVecS2UsBvYv46ynrzWocc92s")
-	ProgramIDTestnet = solana.MustPublicKeyFromBase58("8tfDNiaEyrV6Q1U4DEXrEigs9DoDtkugzFbybENEbCDz")
-	ProgramIDMainnet = solana.MustPublicKeyFromBase58("FsJ3A3u2vn5cTVofAjvy6y5kwABJAqYWpe4975bi2epH")
-)
-
-// Root mapping account IDs listing the products in the Pyth oracle program.
-var (
-	MappingKeyDevnet  = solana.MustPublicKeyFromBase58("BmA9Z6FjioHJPpjT39QazZyhDRUdZy2ezwx4GiDdE2u2")
-	MappingKeyTestnet = solana.MustPublicKeyFromBase58("AFmdnt9ng1uVxqCmqwQJDAYC5cKTkw8gJKSM5PnzuF6z")
-	MappingKeyMainnet = solana.MustPublicKeyFromBase58("AHtgzX45WTKfkPG53L6WYhGEXwQkN1BVknET3sVsLL8J")
-)
-
 func init() {
-	solana.RegisterInstructionDecoder(ProgramIDDevnet, newInstructionDecoder(ProgramIDDevnet))
-	solana.RegisterInstructionDecoder(ProgramIDTestnet, newInstructionDecoder(ProgramIDTestnet))
-	solana.RegisterInstructionDecoder(ProgramIDMainnet, newInstructionDecoder(ProgramIDMainnet))
+	solana.RegisterInstructionDecoder(Devnet.Program, newInstructionDecoder(Devnet.Program))
+	solana.RegisterInstructionDecoder(Testnet.Program, newInstructionDecoder(Testnet.Program))
+	solana.RegisterInstructionDecoder(Mainnet.Program, newInstructionDecoder(Mainnet.Program))
 }
 
 // Pyth program instructions.