decoupled log instance and info

Makes things a bit more modular.  As part of this process I also
replaced ct/x509 with crypto/x509, which already suits our needs.

1 files changed, 58 insertions, 30 deletions

diff --git a/instance.go b/instance.go
index c8aaca3..d4fc004 100644
--- a/instance.go
+++ b/instance.go
@@ -1,53 +1,81 @@
 package stfe
 
 import (
+	"crypto"
+	"crypto/x509"
+	"fmt"
 	"time"
 
+	"encoding/base64"
 	"net/http"
 
 	"github.com/golang/glog"
 	"github.com/google/trillian"
-
-	"github.com/google/certificate-transparency-go/trillian/ctfe"
-	ctutil "github.com/google/certificate-transparency-go/trillian/util"
 )
 
-// instance groups information about a specific STFE instance.
-type instance struct {
-	prefix      string
-	logID       int64
-	client      trillian.TrillianLogClient
-	deadline    time.Duration
-	anchors     ctfe.CertValidationOpts
-	anchorsPool ctfe.PEMCertPool // TODO: merge anchors and anchorsPool
-	timesource  ctutil.TimeSource
+// Instance is an instance of a particular log front-end
+type Instance struct {
+	LogParameters *LogParameters
+	Client        trillian.TrillianLogClient
+	Deadline      time.Duration
+}
+
+// LogParameters is a collection of log parameters
+type LogParameters struct {
+	LogId      []byte // used externally by everyone
+	TreeId     int64  // used internally by Trillian
+	Prefix     string
+	AnchorPool *x509.CertPool      // for chain verification
+	AnchorList []*x509.Certificate // for access to the raw certificates
+	Signer     crypto.Signer
+}
+
+// NewInstance returns an initialized Instance
+func NewInstance(lp *LogParameters, client trillian.TrillianLogClient, deadline time.Duration, mux *http.ServeMux) (*Instance, error) {
+	i := &Instance{
+		LogParameters: lp,
+		Client:        client,
+		Deadline:      deadline,
+	}
+	i.registerHandlers(mux)
+	return i, nil
 }
 
-// NewInstance returns a new STFE instance
-func NewInstance(prefix string, id int64, client trillian.TrillianLogClient, deadline time.Duration, timesource ctutil.TimeSource, anchors ctfe.CertValidationOpts, anchorsPool ctfe.PEMCertPool) *instance {
-	return &instance{
-		prefix:      prefix,
-		logID:       id,
-		client:      client,
-		deadline:    deadline,
-		timesource:  timesource,
-		anchors:     anchors,
-		anchorsPool: anchorsPool,
+// NewLogParameters returns an initialized LogParameters
+func NewLogParameters(logId []byte, treeId int64, prefix string, anchorPath string) (*LogParameters, error) {
+	anchorList, anchorPool, err := LoadTrustAnchors(anchorPath)
+	if err != nil {
+		return nil, err
 	}
+
+	return &LogParameters{
+		LogId:      logId,
+		TreeId:     treeId,
+		Prefix:     prefix,
+		AnchorPool: anchorPool,
+		AnchorList: anchorList,
+	}, nil
+}
+
+func (i *Instance) String() string {
+	return fmt.Sprintf("%s Deadline(%v)\n", i.LogParameters, i.Deadline)
+}
+
+func (p *LogParameters) String() string {
+	return fmt.Sprintf("LogId(%s) TreeId(%d) Prefix(%s) NumAnchors(%d)", base64.StdEncoding.EncodeToString(p.LogId), p.TreeId, p.Prefix, len(p.AnchorList))
 }
 
-// addEndpoints registers STFE handler functions for the respective HTTP paths
-func (i *instance) AddEndpoints(mux *http.ServeMux) {
+func (i *Instance) registerHandlers(mux *http.ServeMux) {
 	for _, endpoint := range []struct {
 		path    string
 		handler appHandler
 	}{
-		{i.prefix + "/add-entry", appHandler{instance: i, handler: addEntry, endpoint: "add-entry", method: http.MethodPost}},
-		{i.prefix + "/get-entries", appHandler{instance: i, handler: getEntries, endpoint: "get-entries", method: http.MethodGet}},
-		{i.prefix + "/get-anchors", appHandler{instance: i, handler: getAnchors, endpoint: "get-anchors", method: http.MethodGet}},
-		{i.prefix + "/get-proof-by-hash", appHandler{instance: i, handler: getProofByHash, endpoint: "get-proof-by-hash", method: http.MethodGet}},
-		{i.prefix + "/get-consistency-proof", appHandler{instance: i, handler: getConsistencyProof, endpoint: "get-consistency-proof", method: http.MethodGet}},
-		{i.prefix + "/get-sth", appHandler{instance: i, handler: getSth, endpoint: "get-sth", method: http.MethodGet}},
+		{i.LogParameters.Prefix + "/add-entry", appHandler{instance: i, handler: addEntry, endpoint: "add-entry", method: http.MethodPost}},
+		{i.LogParameters.Prefix + "/get-entries", appHandler{instance: i, handler: getEntries, endpoint: "get-entries", method: http.MethodGet}},
+		{i.LogParameters.Prefix + "/get-anchors", appHandler{instance: i, handler: getAnchors, endpoint: "get-anchors", method: http.MethodGet}},
+		{i.LogParameters.Prefix + "/get-proof-by-hash", appHandler{instance: i, handler: getProofByHash, endpoint: "get-proof-by-hash", method: http.MethodGet}},
+		{i.LogParameters.Prefix + "/get-consistency-proof", appHandler{instance: i, handler: getConsistencyProof, endpoint: "get-consistency-proof", method: http.MethodGet}},
+		{i.LogParameters.Prefix + "/get-sth", appHandler{instance: i, handler: getSth, endpoint: "get-sth", method: http.MethodGet}},
 	} {
 		glog.Infof("adding handler for %v", endpoint.path)
 		mux.Handle(endpoint.path, endpoint.handler)