Fabric sdk-go usage

The flow to use go-sdk to create a new channel.

1. Get configuration from a configuration file using config.FromFile(path_to_config_file), this returns a ConfigProvider type.
2. Use ConfigProvider function and fabsdk.Option to create a sdk.
        sdk := fabsdk.New(configOpt, sdkOpts...)
3.  Use sdk.Context to create a client context.

clientContext := sdk.Context(fabsdk.WithUser(orgAdmin),

fabsdk.WithOrg(ordererOrgName))

4. Use resmgmt to create a new res management client

resMgmtClient, err := resmgmt.New(clientContext)

5. Use the resMgmtClient, orgName, and the sdk context to create a mspClient

mspClient, err := mspclient.New(sdk.Context(),

mspclient.WithOrg(orgName))

6. Get AdminIdentity using the orgAdmin string.

adminIdentity, err := mspClient.GetSigningIdentity(orgAdmin)

7. Use resmgmt.SaveChannelRequest.

    req := resmgmt.SaveChannelRequest{ChannelID: channelID,

             ChannelConfigPath: integration.GetChannelConfigPath(channelID + ".tx"),

             SigningIdentities: []msp.SigningIdentity{adminIdentity}}

8. Save the channel

    txID, err := resMgmtClient.SaveChannel(req,

resmgmt.WithRetry(retry.DefaultResMgmtOpts),

resmgmt.WithOrdererEndpoint("orderer.example.com"))

9. Make sure things went well.    

    require.Nil(t, err, "error should be nil")

    require.NotEmpty(t, txID, "transaction ID should be populated")