# Fabric 1.1源代碼分析之 Chaincode（鏈碼）初始化 #ChaincodeSupport（鏈碼支持服務端）
## 1、Endorser概述
1、Endorser相關代碼分佈在protos/peer/peer.pb.go和core/endorser目錄。
* 在peer/node/start.go的serve（） 方法中註冊了 endoser服務
serverEndorser := endorser.NewEndorserServer(privDataDist, &endorser.SupportImpl{})
libConf := library.Config{}
if err = viperutil.EnhancedExactUnmarshalKey("peer.handlers", &libConf); err != nil {
return errors.WithMessage(err, "could not load YAML config")
}
authFilters := library.InitRegistry(libConf).Lookup(library.Auth).([]authHandler.Filter)
auth := authHandler.ChainFilters(serverEndorser, authFilters...)
// Register the Endorser server
pb.RegisterEndorserServer(peerServer.Server(), auth)
* protos/peer/peer.pb.go，EndorserServer接口定義。
type EndorserServer interface {
ProcessProposal(context.Context, *SignedProposal) (*ProposalResponse, error)
}
* core/endorser目錄：
* endorser.go，EndorserServer接口實現，即Endorser結構體及方法，以及EndorserServer服務端 ProcessProposal處理流程。
* endorser.go，Support接口定義及實現 type SupportImpl struct(support.go)。
## 2、endorser中的EndorserServer接口實現方法
* // ProcessProposal process the Proposal 處理客戶端傳過來的提案。peer chaincode instantiate初始化合約命令也是一種提案，最終服務端此處是入口
```go
func (e *Endorser) ProcessProposal(ctx context.Context, signedProp *pb.SignedProposal) (*pb.ProposalResponse, error) {
addr := util.ExtractRemoteAddress(ctx)
endorserLogger.Debug("Entering: Got request from", addr)
defer endorserLogger.Debugf("Exit: request from", addr)
//0 -- check and validate 對提案進行預處理，檢查消息有校性及其權限
vr, err := e.preProcess(signedProp)
if err != nil {
resp := vr.resp
return resp, err
}
prop, hdrExt, chainID, txid := vr.prop, vr.hdrExt, vr.chainID, vr.txid
// obtaining once the tx simulator for this proposal. This will be nil
// for chainless proposals
// Also obtain a history query executor for history queries, since tx simulator does not cover history
var txsim ledger.TxSimulator
var historyQueryExecutor ledger.HistoryQueryExecutor
if chainID != "" {
if txsim, err = e.s.GetTxSimulator(chainID, txid); err != nil {
return &pb.ProposalResponse{Response: &pb.Response{Status: 500, Message: err.Error()}}, err
}
if historyQueryExecutor, err = e.s.GetHistoryQueryExecutor(chainID); err != nil {
return &pb.ProposalResponse{Response: &pb.Response{Status: 500, Message: err.Error()}}, err
}
// Add the historyQueryExecutor to context
// TODO shouldn't we also add txsim to context here as well? Rather than passing txsim parameter
// around separately, since eventually it gets added to context anyways
ctx = context.WithValue(ctx, chaincode.HistoryQueryExecutorKey, historyQueryExecutor)
defer txsim.Done()
}
//this could be a request to a chainless SysCC
// TODO: if the proposal has an extension, it will be of type ChaincodeAction;
// if it's present it means that no simulation is to be performed because
// we're trying to emulate a submitting peer. On the other hand, we need
// to validate the supplied action before endorsing it
/*1 -- simulate //如果是擴展提案，可能是一個鏈碼操作 調用本文件中的simulateProposal()->callChaincode()->Execute()(core/endorser/support.go switch spec.(type) { case *pb.ChaincodeDeploymentSpec:return chaincode.Execute(ctxt, cccid, spec))
support.go中的邏輯判斷如果是初始化合約命令最終執行 core/chaincode/chaincode_support.go中的 Execute方法
*/
cd, res, simulationResult, ccevent, err := e.simulateProposal(ctx, chainID, txid, signedProp, prop, hdrExt.ChaincodeId, txsim)
if err != nil {
return &pb.ProposalResponse{Response: &pb.Response{Status: 500, Message: err.Error()}}, err
}
if res != nil {
if res.Status >= shim.ERROR {
endorserLogger.Errorf("[%s][%s] simulateProposal() resulted in chaincode %s response status %d for txid: %s", chainID, shorttxid(txid), hdrExt.ChaincodeId, res.Status, txid)
var cceventBytes []byte
if ccevent != nil {
cceventBytes, err = putils.GetBytesChaincodeEvent(ccevent)
if err != nil {
return nil, errors.Wrap(err, "failed to marshal event bytes")
}
}
pResp, err := putils.CreateProposalResponseFailure(prop.Header, prop.Payload, res, simulationResult, cceventBytes, hdrExt.ChaincodeId, hdrExt.PayloadVisibility)
if err != nil {
return &pb.ProposalResponse{Response: &pb.Response{Status: 500, Message: err.Error()}}, err
}
return pResp, &chaincodeError{res.Status, res.Message}
}
}
//2 -- endorse and get a marshalled ProposalResponse message
var pResp *pb.ProposalResponse
//TODO till we implement global ESCC, CSCC for system chaincodes
//chainless proposals (such as CSCC) don't have to be endorsed
if chainID == "" {
pResp = &pb.ProposalResponse{Response: res}
} else {
pResp, err = e.endorseProposal(ctx, chainID, txid, signedProp, prop, res, simulationResult, ccevent, hdrExt.PayloadVisibility, hdrExt.ChaincodeId, txsim, cd)
if err != nil {
return &pb.ProposalResponse{Response: &pb.Response{Status: 500, Message: err.Error()}}, err
}
if pResp != nil {
if res.Status >= shim.ERRORTHRESHOLD {
endorserLogger.Debugf("[%s][%s] endorseProposal() resulted in chaincode %s error for txid: %s", chainID, shorttxid(txid), hdrExt.ChaincodeId, txid)
return pResp, &chaincodeError{res.Status, res.Message}
}
}
}
// Set the proposal response payload - it
// contains the "return value" from the
// chaincode invocation
pResp.Response.Payload = res.Payload
return pResp, nil
}
```
## 2、鏈碼相關處理
* 在core/endorser/support.go 文件中 Execute方法判斷是初始化還是執行合約。
```go
//Execute - execute proposal, return original response of chaincode
func (s *SupportImpl) Execute(ctxt context.Context, cid, name, version, txid string, syscc bool, signedProp *pb.SignedProposal, prop *pb.Proposal, spec interface{}) (*pb.Response, *pb.ChaincodeEvent, error) {
cccid := ccprovider.NewCCContext(cid, name, version, txid, syscc, signedProp, prop)
switch spec.(type) {
case *pb.ChaincodeDeploymentSpec:
//初始化 core/chaincode/exectransaction.go Execute()
return chaincode.Execute(ctxt, cccid, spec)
case *pb.ChaincodeInvocationSpec:
cis := spec.(*pb.ChaincodeInvocationSpec)
// decorate the chaincode input
decorators := library.InitRegistry(library.Config{}).Lookup(library.Decoration).([]decoration.Decorator)
cis.ChaincodeSpec.Input.Decorations = make(map[string][]byte)
cis.ChaincodeSpec.Input = decoration.Apply(prop, cis.ChaincodeSpec.Input, decorators...)
cccid.ProposalDecorations = cis.ChaincodeSpec.Input.Decorations
//執行合約 core/chaincode/chaincodeexec.go ExecuteChaincode
return chaincode.ExecuteChaincode(ctxt, cccid, cis.ChaincodeSpec.Input.Args)
default:
panic("programming error, unkwnown spec type")
}
}
```
## 3、初始化鏈碼方法 core/chaincode/exectransaction.go 文件中的Execute()
```go
//Execute - execute proposal, return original response of chaincode
func Execute(ctxt context.Context, cccid *ccprovider.CCContext, spec interface{}) (*pb.Response, *pb.ChaincodeEvent, error) {
var err error
var cds *pb.ChaincodeDeploymentSpec
var ci *pb.ChaincodeInvocationSpec
//init will call the Init method of a on a chain
cctyp := pb.ChaincodeMessage_INIT
if cds, _ = spec.(*pb.ChaincodeDeploymentSpec); cds == nil {
if ci, _ = spec.(*pb.ChaincodeInvocationSpec); ci == nil {
panic("Execute should be called with deployment or invocation spec")
}
cctyp = pb.ChaincodeMessage_TRANSACTION
}
//調用 core/chaincode/upchaincode_sport.go中的launch方法
_, cMsg, err := theChaincodeSupport.Launch(ctxt, cccid, spec)
if err != nil {
return nil, nil, err
}
cMsg.Decorations = cccid.ProposalDecorations
var ccMsg *pb.ChaincodeMessage
ccMsg, err = createCCMessage(cctyp, cccid.ChainID, cccid.TxID, cMsg)
if err != nil {
return nil, nil, errors.WithMessage(err, "failed to create chaincode message")
}
//判斷chaincode是否啓動，是否超時，返回結果給客戶端
resp, err := theChaincodeSupport.Execute(ctxt, cccid, ccMsg, theChaincodeSupport.executetimeout)
if err != nil {
// Rollback transaction
return nil, nil, errors.WithMessage(err, "failed to execute transaction")
} else if resp == nil {
// Rollback transaction
return nil, nil, errors.Errorf("failed to receive a response for txid (%s)", cccid.TxID)
}
if resp.ChaincodeEvent != nil {
resp.ChaincodeEvent.ChaincodeId = cccid.Name
resp.ChaincodeEvent.TxId = cccid.TxID
}
if resp.Type == pb.ChaincodeMessage_COMPLETED {
res := &pb.Response{}
unmarshalErr := proto.Unmarshal(resp.Payload, res)
if unmarshalErr != nil {
return nil, nil, errors.Wrap(unmarshalErr, fmt.Sprintf("failed to unmarshal response for txid (%s)", cccid.TxID))
}
// Success
return res, resp.ChaincodeEvent, nil
} else if resp.Type == pb.ChaincodeMessage_ERROR {
// Rollback transaction
return nil, resp.ChaincodeEvent, errors.Errorf("transaction returned with failure: %s", string(resp.Payload))
}
//TODO - this should never happen ... a panic is more appropriate but will save that for future
return nil, nil, errors.Errorf("receive a response for txid (%s) but in invalid state (%d)", cccid.TxID, resp.Type)
}
```
## 4、 core/chaincode/upchaincode_sport.go 的Launch()
```go
// Launch will launch the chaincode if not running (if running return nil) and will wait for handler of the chaincode to get into FSM ready state. 啓動鏈碼成功後FSM狀態機推到ready狀態
func (chaincodeSupport *ChaincodeSupport) Launch(context context.Context, cccid *ccprovider.CCContext, spec interface{}) (*pb.ChaincodeID, *pb.ChaincodeInput, error) {
//build the chaincode
var cID *pb.ChaincodeID
var cMsg *pb.ChaincodeInput
var cds *pb.ChaincodeDeploymentSpec
var ci *pb.ChaincodeInvocationSpec
if cds, _ = spec.(*pb.ChaincodeDeploymentSpec); cds == nil {
if ci, _ = spec.(*pb.ChaincodeInvocationSpec); ci == nil {
panic("Launch should be called with deployment or invocation spec")
}
}
if cds != nil {
cID = cds.ChaincodeSpec.ChaincodeId
cMsg = cds.ChaincodeSpec.Input
} else {
cID = ci.ChaincodeSpec.ChaincodeId
cMsg = ci.ChaincodeSpec.Input
}
canName := cccid.GetCanonicalName()
chaincodeSupport.runningChaincodes.Lock()
var chrte *chaincodeRTEnv
var ok bool
var err error
//if its in the map, there must be a connected stream...nothing to do
if chrte, ok = chaincodeSupport.chaincodeHasBeenLaunched(canName); ok {
if !chrte.handler.registered {
chaincodeSupport.runningChaincodes.Unlock()
err = errors.Errorf("premature execution - chaincode (%s) launched and waiting for registration", canName)
chaincodeLogger.Debugf("%+v", err)
return cID, cMsg, err
}
if chrte.handler.isRunning() {
if chaincodeLogger.IsEnabledFor(logging.DEBUG) {
chaincodeLogger.Debugf("chaincode is running(no need to launch) : %s", canName)
}
chaincodeSupport.runningChaincodes.Unlock()
return cID, cMsg, nil
}
chaincodeLogger.Debugf("Container not in READY state(%s)...send init/ready", chrte.handler.FSM.Current())
} else {
//chaincode is not up... but is the launch process underway? this is
//strictly not necessary as the actual launch process will catch this
//(in launchAndWaitForRegister), just a bit of optimization for thundering
//herds 判斷鏈碼是否啓動
if chaincodeSupport.launchStarted(canName) {
chaincodeSupport.runningChaincodes.Unlock()
err = errors.Errorf("premature execution - chaincode (%s) is being launched", canName)
return cID, cMsg, err
}
}
chaincodeSupport.runningChaincodes.Unlock()
if cds == nil {
if cccid.Syscc {
return cID, cMsg, errors.Errorf("a syscc should be running (it cannot be launched) %s", canName)
}
if chaincodeSupport.userRunsCC {
chaincodeLogger.Error("You are attempting to perform an action other than Deploy on Chaincode that is not ready and you are in developer mode. Did you forget to Deploy your chaincode?")
}
var depPayload []byte
//hopefully we are restarting from existing image and the deployed transaction exists
//(this will also validate the ID from the LSCC if we're not using the config-tree approach)
depPayload, err = GetCDS(context, cccid.TxID, cccid.SignedProposal, cccid.Proposal, cccid.ChainID, cID.Name)
if err != nil {
return cID, cMsg, errors.WithMessage(err, fmt.Sprintf("could not get ChaincodeDeploymentSpec for %s", canName))
}
if depPayload == nil {
return cID, cMsg, errors.WithMessage(err, fmt.Sprintf("nil ChaincodeDeploymentSpec for %s", canName))
}
cds = &pb.ChaincodeDeploymentSpec{}
//Get lang from original deployment
err = proto.Unmarshal(depPayload, cds)
if err != nil {
return cID, cMsg, errors.Wrap(err, fmt.Sprintf("failed to unmarshal deployment transactions for %s", canName))
}
}
//from here on : if we launch the container and get an error, we need to stop the container
//launch container if it is a System container or not in dev mode
if (!chaincodeSupport.userRunsCC || cds.ExecEnv == pb.ChaincodeDeploymentSpec_SYSTEM) && (chrte == nil || chrte.handler == nil) {
//NOTE-We need to streamline code a bit so the data from LSCC gets passed to this thus
//avoiding the need to go to the FS. In particular, we should use cdsfs completely. It is
//just a vestige of old protocol that we continue to use ChaincodeDeploymentSpec for
//anything other than Install. In particular, instantiate, invoke, upgrade should be using
//just some form of ChaincodeInvocationSpec.
//
//But for now, if we are invoking we have gone through the LSCC path above. If instantiating
//or upgrading currently we send a CDS with nil CodePackage. In this case the codepath
//in the endorser has gone through LSCC validation. Just get the code from the FS.
if cds.CodePackage == nil {
//no code bytes for these situations
if !(chaincodeSupport.userRunsCC || cds.ExecEnv == pb.ChaincodeDeploymentSpec_SYSTEM) {
ccpack, err := ccprovider.GetChaincodeFromFS(cID.Name, cID.Version)
if err != nil {
return cID, cMsg, err
}
cds = ccpack.GetDepSpec()
chaincodeLogger.Debugf("launchAndWaitForRegister fetched %d bytes from file system", len(cds.CodePackage))
}
}
//_platforms.go中的GenerateDockerBuild作爲返回值作爲core.go中的BuildSpecFactory()的實現_
builder := func() (io.Reader, error) { return platforms.GenerateDockerBuild(cds) }
err = chaincodeSupport.launchAndWaitForRegister(context, cccid, cds, &ccLauncherImpl{context, chaincodeSupport, cccid, cds, builder})
if err != nil {
chaincodeLogger.Errorf("launchAndWaitForRegister failed: %+v", err)
return cID, cMsg, err
}
}
if err == nil {
//launch will set the chaincode in Ready state
err = chaincodeSupport.sendReady(context, cccid, chaincodeSupport.ccStartupTimeout)
if err != nil {
err = errors.WithMessage(err, "failed to init chaincode")
chaincodeLogger.Errorf("%+v", err)
errIgnore := chaincodeSupport.Stop(context, cccid, cds)
if errIgnore != nil {
chaincodeLogger.Errorf("stop failed: %+v", errIgnore)
}
}
chaincodeLogger.Debug("sending init completed")
}
chaincodeLogger.Debug("LaunchChaincode complete")
return cID, cMsg, err
}
```
* 經過調用 launchAndWaitForRegister()->launch()->core/container/controller.go VMCProcess()
因爲controller.go中有好幾個 do() 但是在launch中傳進來的確是
```go
sir := container.StartImageReq{CCID: ccid, Builder: ccl.builder, Args: args, Env: env, FilesToUpload: filesToUpload, PrelaunchFunc: preLaunchFunc}
```
## 所以下面的VMCProcess中的 req.do 是執行的func (si StartImageReq) do(ctxt context.Context, v api.VM)VMCResp VMCReqIntf是接口定義
ccLauncherImpl結構體中的builder就是platforms.go中的GenerateDockerBuild()
func VMCProcess(ctxt context.Context, vmtype string, req VMCReqIntf) (interface{}, error)
VMCProcess中調用 了v.Start() //core.go中的接口vm中定義的方法，其實現在dockercontroller.go中
## 4、 core/container包
* core/container包提供了對容器的操作
core/container/api/core.go中提供接口及函數類型定義
```go
type BuildSpecFactory func() (io.Reader, error) //坑
type PrelaunchFunc func() error
type VM interface {
Deploy(ctxt context.Context, ccid ccintf.CCID, args []string, env []string, reader io.Reader) error
Start(ctxt context.Context, ccid ccintf.CCID, args []string, env []string, filesToUpload map[string][]byte, builder BuildSpecFactory, preLaunchFunc PrelaunchFunc) error
Stop(ctxt context.Context, ccid ccintf.CCID, timeout uint, dontkill bool, dontremove bool) error
Destroy(ctxt context.Context, ccid ccintf.CCID, force bool, noprune bool) error
GetVMName(ccID ccintf.CCID, format func(string) (string, error)) (string, error)
}
```
core/container/dockercontroller/dockercontroller.go提供了對上面接口的實現,並且定義如下接口
```go
type dockerClient interface {
// CreateContainer creates a docker container, returns an error in case of failure
CreateContainer(opts docker.CreateContainerOptions) (*docker.Container, error)
// UploadToContainer uploads a tar archive to be extracted to a path in the
// filesystem of the container.
UploadToContainer(id string, opts docker.UploadToContainerOptions) error
// StartContainer starts a docker container, returns an error in case of failure
StartContainer(id string, cfg *docker.HostConfig) error
// AttachToContainer attaches to a docker container, returns an error in case of
// failure
AttachToContainer(opts docker.AttachToContainerOptions) error
// BuildImage builds an image from a tarball's url or a Dockerfile in the input
// stream, returns an error in case of failure
BuildImage(opts docker.BuildImageOptions) error
// RemoveImageExtended removes a docker image by its name or ID, returns an
// error in case of failure
RemoveImageExtended(id string, opts docker.RemoveImageOptions) error
// StopContainer stops a docker container, killing it after the given timeout
// (in seconds). Returns an error in case of failure
StopContainer(id string, timeout uint) error
// KillContainer sends a signal to a docker container, returns an error in
// case of failure
KillContainer(opts docker.KillContainerOptions) error
// RemoveContainer removes a docker container, returns an error in case of failure
RemoveContainer(opts docker.RemoveContainerOptions) error
}
```
* 上面dockerClient接口實現類通過方法
// getClient returns an instance that implements dockerClient interface
type getClient func() (dockerClient, error) 返回其實現 類
* dockercontroller.go中的Start方法實現 Start方法控制了合約容器生成到啓動的過程
/Start starts a container using a previously created docker image
func (vm *DockerVM) Start(ctxt context.Context, ccid ccintf.CCID,
args []string, env []string, filesToUpload map[string][]byte, builder container.BuildSpecFactory, prelaunchFunc container.PrelaunchFunc) error {
imageID, err := vm.GetVMName(ccid, formatImageName)
if err != nil {
return err
}
client, err := vm.getClientFnc()
if err != nil {
dockerLogger.Debugf("start - cannot create client %s", err)
return err
}
//獲取容器名稱 規則 peer節點ID+domainname+合約名+隨機數
containerID, err := vm.GetVMName(ccid, nil)
if err != nil {
return err
}
attachStdout := viper.GetBool("vm.docker.attachStdout")
//stop,force remove if necessary
dockerLogger.Debugf("Cleanup container %s", containerID)
//根據最後兩位參數選擇調用 stopContainer或者killcontainer或者removecontainer
vm.stopInternal(ctxt, client, containerID, 0, false, false)
dockerLogger.Debugf("Start container %s", containerID)
//創建合約容器 第一次佈署合約創建容器都會失敗。err不會爲空因爲沒有合約容器鏡像
err = vm.createContainer(ctxt, client, imageID, containerID, args, env, attachStdout)
if err != nil {
//if image not found try to create image and
//如果鏡像沒找到則重新生成dockerfile文件
if err == docker.ErrNoSuchImage {
if builder != nil {
dockerLogger.Debugf("start-could not find image <%s> (container id <%s>), because of <%s>..."+
"attempt to recreate image", imageID, containerID, err)
//********此處builder()調用 的是core/chaincdoe/platforms/platforms.go中的GenerateDockerBuild()函數**********
//********產生一個DockerFile並寫到reader中
reader, err1 := builder()
if err1 != nil {
dockerLogger.Errorf("Error creating image builder for image <%s> (container id <%s>), "+
"because of <%s>", imageID, containerID, err1)
}
//根據builder()產生的DockerFile生成一個合約鏡像文件.但是在/platforms/node/platform.go中會先根據 ccenv鏡像先
//npm install 安裝鏈碼. 此處會從reader中的DockerFile 生成新的鏡像(繼承自fabric-baseimage)
if err1 = vm.deployImage(client, ccid, args, env, reader); err1 != nil {
return err1
}
dockerLogger.Debug("start-recreated image successfully")
//創建容器
if err1 = vm.createContainer(ctxt, client, imageID, containerID, args, env, attachStdout); err1 != nil {
dockerLogger.Errorf("start-could not recreate container post recreate image: %s", err1)
return err1
}
} else {
dockerLogger.Errorf("start-could not find image <%s>, because of %s", imageID, err)
return err
}
} else {
dockerLogger.Errorf("start-could not recreate container <%s>, because of %s", containerID, err)
return err
}
}
if attachStdout {
// Launch a few go-threads to manage output streams from the container.
// They will be automatically destroyed when the container exits
//core.yml配置文件如果vm.docker.attachStdout設置爲true 則會輸出合約docker容器的日誌信息,默認關閉
attached := make(chan struct{})
r, w := io.Pipe()
go func() {
// AttachToContainer will fire off a message on the "attached" channel once the
// attachment completes, and then block until the container is terminated.
// The returned error is not used outside the scope of this function. Assign the
// error to a local variable to prevent clobbering the function variable 'err'.
err := client.AttachToContainer(docker.AttachToContainerOptions{
Container: containerID,
OutputStream: w,
ErrorStream: w,
Logs: true,
Stdout: true,
Stderr: true,
Stream: true,
Success: attached,
})
// If we get here, the container has terminated. Send a signal on the pipe
// so that downstream may clean up appropriately
_ = w.CloseWithError(err)
}()
go func() {
// Block here until the attachment completes or we timeout
select {
case <-attached:
// successful attach
case <-time.After(10 * time.Second):
dockerLogger.Errorf("Timeout while attaching to IO channel in container %s", containerID)
return
}
// Acknowledge the attachment? This was included in the gist I followed
// (http://bit.ly/2jBrCtM). Not sure it's actually needed but it doesn't
// appear to hurt anything.
attached <- struct{}{}
// Establish a buffer for our IO channel so that we may do readline-style
// ingestion of the IO, one log entry per line
is := bufio.NewReader(r)
// Acquire a custom logger for our chaincode, inheriting the level from the peer
containerLogger := flogging.MustGetLogger(containerID)
logging.SetLevel(logging.GetLevel("peer"), containerID)
for {
// Loop forever dumping lines of text into the containerLogger
// until the pipe is closed
line, err2 := is.ReadString('\n')
if err2 != nil {
switch err2 {
case io.EOF:
dockerLogger.Infof("Container %s has closed its IO channel", containerID)
default:
dockerLogger.Errorf("Error reading container output: %s", err2)
}
return
}
containerLogger.Info(line)
}
}()
}
// upload specified files to the container before starting it
// this can be used for configurations such as TLS key and certs
//容器啓動前上傳指定文件到容器內部 如ca證書文件tls證書文件
if len(filesToUpload) != 0 {
// the docker upload API takes a tar file, so we need to first
// consolidate the file entries to a tar
payload := bytes.NewBuffer(nil)
gw := gzip.NewWriter(payload)
tw := tar.NewWriter(gw)
for path, fileToUpload := range filesToUpload {
cutil.WriteBytesToPackage(path, fileToUpload, tw)
}
// Write the tar file out
if err = tw.Close(); err != nil {
return fmt.Errorf("Error writing files to upload to Docker instance into a temporary tar blob: %s", err)
}
gw.Close()
err = client.UploadToContainer(containerID, docker.UploadToContainerOptions{
InputStream: bytes.NewReader(payload.Bytes()),
Path: "/",
NoOverwriteDirNonDir: false,
})
if err != nil {
return fmt.Errorf("Error uploading files to the container instance %s: %s", containerID, err)
}
}
//調用chaincode_support.go中preLaunchSetup()
if prelaunchFunc != nil {
if err = prelaunchFunc(); err != nil {
return err
}
}
// start container with HostConfig was deprecated since v1.10 and removed in v1.2
//啓動容器
err = client.StartContainer(containerID, nil)
if err != nil {
dockerLogger.Errorf("start-could not start container: %s", err)
return err
}
dockerLogger.Debugf("Started container %s", containerID)
return nil
}
##5、 core/chaincode/platforms包
* core/chaincode/platforms目錄，鏈碼的編寫語言平臺實現，如golang或java。
platforms.go，Platform接口定義，及platforms相關工具函數。
util目錄，Docker相關工具函數。
java目錄，java語言平臺實現。
node目錄，nodejs語言平臺實現。
* Platform接口定義
```go
type Platform interface {
//驗證ChaincodeSpec
ValidateSpec(spec *pb.ChaincodeSpec) error
//驗證ChaincodeDeploymentSpec
ValidateDeploymentSpec(spec *pb.ChaincodeDeploymentSpec) error
//獲取部署Payload
GetDeploymentPayload(spec *pb.ChaincodeSpec) ([]byte, error)
//生成Dockerfile
GenerateDockerfile(spec *pb.ChaincodeDeploymentSpec) (string, error)
//生成DockerBuild
GenerateDockerBuild(spec *pb.ChaincodeDeploymentSpec, tw *tar.Writer) error
}
//代碼在core/chaincode/platforms/platforms.go
```
### 5.1、platforms相關工具函數
```go
//按鏈碼類型構造Platform接口實例，如golang.Platform{}
func Find(chaincodeType pb.ChaincodeSpec_Type) (Platform, error)
//調取platform.GetDeploymentPayload(spec)，獲取部署Payload
func GetDeploymentPayload(spec *pb.ChaincodeSpec) ([]byte, error)
//優先獲取tls根證書，如無則獲取tls證書
func getPeerTLSCert() ([]byte, error)
//調取platform.GenerateDockerfile(cds)，創建Dockerfile
func generateDockerfile(platform Platform, cds *pb.ChaincodeDeploymentSpec, tls bool) ([]byte, error)
//調取platform.GenerateDockerBuild(cds, tw)，創建DockerBuild
func generateDockerBuild(platform Platform, cds *pb.ChaincodeDeploymentSpec, inputFiles InputFiles, tw *tar.Writer) error
//調取generateDockerfile(platform, cds, cert != nil)
func GenerateDockerBuild(cds *pb.ChaincodeDeploymentSpec) (io.Reader, error)
//代碼在core/chaincode/platforms/platforms.go
```
### 5.2 platforms介紹
* dockercontroller.go中的Start()裏有build()方法調用 ，前文介紹過會調用platforms.GenerateDockerBuild()
```go
func GenerateDockerBuild(cds *pb.ChaincodeDeploymentSpec) (io.Reader, error) {
inputFiles := make(InputFiles)
// ----------------------------------------------------------------------------------------------------
// Determine our platform driver from the spec
// ----------------------------------------------------------------------------------------------------
//查找平臺相關實現 Nodejs在 platforms/node/platform.go中 go在platforms/golang/platform.go中
platform, err := _Find(cds.ChaincodeSpec.Type)
if err != nil {
return nil, fmt.Errorf("Failed to determine platform type: %s", err)
}
// ----------------------------------------------------------------------------------------------------
// Generate the Dockerfile specific to our context
// ----------------------------------------------------------------------------------------------------
//生成各平臺DockerFile(nodejs java go)
dockerFile, err := _generateDockerfile(platform, cds)
if err != nil {
return nil, fmt.Errorf("Failed to generate a Dockerfile: %s", err)
}
inputFiles["Dockerfile"] = dockerFile
// ----------------------------------------------------------------------------------------------------
// Finally, launch an asynchronous process to stream all of the above into a docker build context
// ----------------------------------------------------------------------------------------------------
input, output := io.Pipe()
go func() {
gw := gzip.NewWriter(output)
tw := tar.NewWriter(gw)
//生成鏡像
err := _generateDockerBuild(platform, cds, inputFiles, tw)
if err != nil {
logger.Error(err)
}
tw.Close()
gw.Close()
output.CloseWithError(err)
}()
return input, nil
}
```
* platforms/node/platform.go GenerateDockerBuild函數
func (nodePlatform *Platform) GenerateDockerBuild(cds *pb.ChaincodeDeploymentSpec, tw *tar.Writer) error {
codepackage := bytes.NewReader(cds.CodePackage)
binpackage := bytes.NewBuffer(nil)
str :=""
//此處是自己修改過的代碼，目的是如果環境變量裏配置了 NODE_REGISTRY 則npm使用這個源
var cusRegisry = os.Getenv("NODE_REGISTRY")
if cusRegisry !=""{
str = "cp -R /chaincode/input/src/. /chaincode/output && cd /chaincode/output && npm config set registry "+cusRegisry+" && npm install --production"
} else {
str = "cp -R /chaincode/input/src/. /chaincode/output && cd /chaincode/output && npm install --production"
}
fmt.Println("cmd........"+str)
//把鏈碼傳到ccenv鏡像的容器裏啓動並安裝 nodejs合約模塊.網絡的原因，很慢。有些模塊還需要編譯二進制文件，可能失敗(composer 合約是這樣)
err := util.DockerBuild(util.DockerBuildOptions{
Cmd: fmt.Sprint(str),
InputStream: codepackage,
OutputStream: binpackage,
})
if err != nil {
return err
}
return cutil.WriteBytesToPackage("binpackage.tar", binpackage.Bytes(), tw)
}
### 5.3、nodejs合約容器啓動編譯流程圖
* nodejs寫合約的話會先啓動ccenv鏡像，並在這個容器裏編譯nodejs合約，完成後拿到編譯好的文件夾，再啓
動baseimage,並且把編譯好的文件放到usr/local/src下面.最後纔是 npm start ...命令啓動.流程圖如下
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