REFACTOR: Add coinmarketcap data, add normalization, and rename from …

…tickerproxy to ticker since we do more than proxy now.

.travis.yml

@@ -3,12 +3,12 @@ go:
 - "1.10"
 script:
 - go test -v *.go
-- go build -o tickerproxyd ./bin/*.go
+- go build -o tickerfetcher ./fetch/*.go
 deploy:
   provider: releases
   api_key:
     secure: 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
-  file: tickerproxyd
+  file: tickerfetcher
   skip_cleanup: true
   on:
     tags: true

Dockerfile

@@ -1,10 +1,10 @@
 FROM golang:1.10
 WORKDIR /go/src/github.com/OpenBazaar/tickerproxy
 COPY . .
-RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build --ldflags '-extldflags "-static"' -o /opt/tickerproxy ./bin/*.go
+RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build --ldflags '-extldflags "-static"' -o /opt/tickerfetcher ./fetch/*.go
 
 FROM scratch
-VOLUME /var/lib/tickerproxy
-COPY --from=0 /opt/tickerproxy /opt/tickerproxy
-COPY --from=0 /etc/ssl/certs/ /etc/ssl/certs/
-CMD ["/opt/tickerproxy"]
+WORKDIR /var/lib/ticker
+COPY --from=0 /opt/tickerfetcher /opt/tickerfetcher
+COPY --from=0 /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/ca-certificates.crt
+CMD ["/opt/tickerfetcher"]

btcavg.go

@@ -0,0 +1,161 @@
+package ticker
+
+import (
+	"crypto/hmac"
+	"crypto/sha256"
+	"encoding/hex"
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"strings"
+	"sync"
+	"time"
+)
+
+const (
+	btcavgFiatEndpoint   = "https://apiv2.bitcoinaverage.com/indices/global/ticker/all?crypto=BTC"
+	btcavgCryptoEndpoint = "https://apiv2.bitcoinaverage.com/indices/crypto/ticker/all"
+)
+
+type btcavgFetcher struct {
+	pubkey  string
+	privkey string
+}
+
+func NewBTCAVGFetcher(pubkey string, privkey string) fetchFn {
+	return func() (exchangeRates, error) {
+		output := exchangeRates{}
+		errCh := make(chan error, 2)
+
+		// Request both endpoints and save their responses
+		wg := sync.WaitGroup{}
+		wg.Add(2)
+		go func() {
+			defer wg.Done()
+			rates, err := fetchBTCAVGResource(btcavgFiatEndpoint, pubkey, privkey)
+			if err != nil {
+				errCh <- err
+				return
+			}
+
+			formatBTCAVGFiatOutput(output, rates)
+		}()
+
+		go func() {
+			defer wg.Done()
+			rates, err := fetchBTCAVGResource(btcavgCryptoEndpoint, pubkey, privkey)
+			if err != nil {
+				errCh <- err
+				return
+			}
+
+			err = formatBTCAVGCryptoOutput(output, rates)
+			if err != nil {
+				errCh <- err
+				return
+			}
+		}()
+		wg.Wait()
+		close(errCh)
+
+		for err := range errCh {
+			return nil, err
+		}
+
+		return output, nil
+	}
+}
+
+// fetchBTCAVGResource gets the response for a given BitcoinAverage endpoint
+func fetchBTCAVGResource(url string, pubkey string, privkey string) (exchangeRates, error) {
+	// Create signed request
+	req, err := http.NewRequest("GET", url, nil)
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Add("X-signature", createBTCAVGSignature(pubkey, privkey))
+
+	// Send the requests
+	resp, err := httpClient.Do(req)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	// Read the response body
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	// Return an error if no success, otherwise deserialize and return our body
+	if resp.StatusCode != 200 {
+		return nil, err
+	}
+
+	rates := make(exchangeRates)
+	err = json.Unmarshal(body, &rates)
+	if err != nil {
+		return nil, err
+	}
+
+	return rates, nil
+}
+
+// formatBTCAVGFiatOutput formats BTC->fiat pairs
+func formatBTCAVGFiatOutput(outgoing exchangeRates, incoming exchangeRates) {
+	for k, v := range incoming {
+		if strings.HasPrefix(k, "BTC") {
+			outgoing[strings.TrimPrefix(k, "BTC")] = v
+		}
+	}
+}
+
+// formatBTCAVGCryptoOutput formats BTC->crypto pairs
+func formatBTCAVGCryptoOutput(outgoing exchangeRates, incoming exchangeRates) error {
+	for symbol, entry := range incoming {
+		trimmedSymbol := strings.TrimSuffix(symbol, "BTC")
+		if symbol == trimmedSymbol {
+			continue
+		}
+		symbol := CanonicalizeSymbol(trimmedSymbol)
+
+		if !IsCorrectIDForSymbol(symbol, entry.ID) {
+			continue
+		}
+
+		if entry.Ask == "" || entry.Bid == "" || entry.Last == "" {
+			continue
+		}
+
+		ask, err := invertAndFormatPrice(entry.Ask)
+		if err != nil {
+			return err
+		}
+		bid, err := invertAndFormatPrice(entry.Bid)
+		if err != nil {
+			return err
+		}
+		last, err := invertAndFormatPrice(entry.Last)
+		if err != nil {
+			return err
+		}
+
+		outgoing[symbol] = exchangeRate{Ask: ask, Bid: bid, Last: last}
+	}
+	return nil
+}
+
+func createBTCAVGSignature(pubkey string, privkey string) string {
+	// Build payload
+	payload := fmt.Sprintf("%d.%s", time.Now().Unix(), pubkey)
+
+	// Generate the HMAC-sha256 signature
+	mac := hmac.New(sha256.New, []byte(privkey))
+	mac.Write([]byte(payload))
+	signature := hex.EncodeToString(mac.Sum(nil))
+
+	// Return the final payload
+	return fmt.Sprintf("%s.%s", payload, signature)
+}

cmc.go

@@ -0,0 +1,95 @@
+package ticker
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+)
+
+const (
+	cmcQueryEndpointTempalte = "https://api.coinmarketcap.com/v2/ticker?convert=BTC&start=%d&limit=%d"
+	cmcQueryFirstID          = 1
+	defaultCMCQueryLimit     = 100
+)
+
+type cmcCoinData struct {
+	ID     int64  `json:"id"`
+	Symbol string `json:"symbol"`
+	Name   string `json:"name"`
+	Quotes struct {
+		BTC struct {
+			Price     json.Number `json:"price"`
+			MarketCap float64     `json:"market_cap"`
+		} `json:"BTC"`
+	} `json:"quotes"`
+}
+
+type cmcResponse struct {
+	Data map[json.Number]cmcCoinData `json:"data"`
+
+	Metadata struct {
+		Count int `json:"num_cryptocurrencies"`
+	} `json:"metadata"`
+}
+
+func FetchCMC() (exchangeRates, error) {
+	output := exchangeRates{}
+
+	resp, err := fetchCMCResource(cmcQueryFirstID, output)
+	if err != nil {
+		return nil, err
+	}
+
+	for i := defaultCMCQueryLimit + cmcQueryFirstID; i < resp.Metadata.Count; i += defaultCMCQueryLimit {
+		_, err = fetchCMCResource(i, output)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return output, nil
+}
+
+func fetchCMCResource(start int, output exchangeRates) (*cmcResponse, error) {
+	resp, err := httpClient.Get(buildCMCQueryEndpoint(start, defaultCMCQueryLimit))
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	payload := &cmcResponse{}
+	err = json.Unmarshal(body, payload)
+	if err != nil {
+		return nil, err
+	}
+
+	for _, entry := range payload.Data {
+		entry.Symbol = CanonicalizeSymbol(entry.Symbol)
+
+		if !IsCorrectIDForSymbol(entry.Symbol, entry.ID) {
+			continue
+		}
+
+		if entry.Quotes.BTC.Price == "" {
+			continue
+		}
+
+		price, err := invertAndFormatPrice(entry.Quotes.BTC.Price)
+		if err != nil {
+			return nil, err
+		}
+
+		output[entry.Symbol] = exchangeRate{Ask: price, Bid: price, Last: price}
+	}
+
+	return payload, nil
+}
+
+func buildCMCQueryEndpoint(start int, limit int) string {
+	return fmt.Sprintf(cmcQueryEndpointTempalte, start, limit)
+}