Use case of --enclave-file in running CCF host

[Chintan Rajvir (chintanr97)]

While running a new CCF host manually, using the cchost or cchost.virtual binaries, the --enclave-file option is required. Currently, I am little confused about its use case based on the explanation in command-line help. I would like to identify the difference between the "user application" which is deployed in the CCF network (for e.g., a sample JavaScript application) and the value passed to this argument.

IMO, if both of these imply the same property, i.e., the user application to be run on CCF, then how can we effectively build a library file for a JavaScript application using cmake? For example, I was attempting to use the forum application at ./samples/apps/forum to be deployed by manually creating a node. For this, initially I tested the CCF node creation functionality using the command:

sudo /opt/ccf/bin/cchost.virtual  \
--enclave-file /opt/ccf/lib/libjs_generic.virtual.so \
--enclave-type virtual \
--consensus cft \
--rpc-address 127.0.0.1:<p1> \
--node-address 127.0.0.1:<p1> \
--ledger-dir ... \
--node-cert-file ... \
start \
--network-cert-file ... \
--member-info ... \
--constitution ...

The above command correctly started a CCF node with the specified enclave file or sample user application. However, I am missing out steps to run, let's say, the Forum JavaScript application on this node directly instead of /opt/ccf/lib/libjs_generic.virtual.so.

For understanding a little deeper, I followed the README.md file here, to deploy the Forum Application as is. The app was deployed correctly with following logs in the shell:

 Starting 1 CCF node...
 Virtual mode enabled
 Started CCF network with the following nodes:
   Node [0] = https://127.0.0.1:8000
 You can now issue business transactions to the libjs_generic application
 Loaded JS application: dist
 Keys and certificates have been copied to the common folder: .workspace_ccf/sandbox_common
 See https://microsoft.github.io/CCF/main/use_apps/issue_commands.html for more information
 Press Ctrl+C to shutdown the network

I went over the sandbox.sh code, followed by start_network.py code in /opt/ccf/bin folder. But, I could not understand the difference between logging of You can now issue business transactions to the libjs_generic application and Loaded JS application: dist. Also, I could not locate a code snippet that would suggest that the JavaScript application was built as shared object and deployed to the network!

Please let me know if I have misunderstood something here, or if I am missing out something.

[Amaury Chamayou (achamayou)]

js_generic is an enclave shared object that contains a reference javascript runtime. The idea is that all JavaScript applications use that, and upload their application code to the KV store, using a governance proposal (see https://microsoft.github.io/CCF/main/build_apps/js_app_bundle.html#deployment for details).

You may find the tutorial helpful (https://microsoft.github.io/CCF/main/build_apps/js_app_ts.html), but please do feel free to ask (or suggest improvements!) if anything is unclear.

[iqsarv]

Amaury Chamayou (@achamayou) Eddy Ashton (@eddyashton) It will be good to callout in the docs that the proposal-based Deployment step should be done after the js_generic app is started using cchost for the app to be run in CCF network.

[ebo1981-cyber]

dear eddyashton
dear achamayou
Is it possible for you to provide me with a video tutorial on installing and running the ccf environment and application ?

[M. Lammers (martijnlammers)]

I happen to have written some shellscripts to automate the process of installation/setting up app development/config files. You still would have to change some of the configs as some things can't be assigned generically, like your DNS/san.
you can find it here. By no means is it professional, but it might help you out. I'll put a manual in the repo.
You can install CCF by running:

$ cd ~
$ git clone https://github.com/martijnlammers/ccfsetup
$ bash ./ccfsetup/ccf_install.sh

[ebo1981-cyber]

At first I am grateful to Mr. mAlyanak
Your guide is great, but during implementation I had a problem and I am unable to solve it ,when install npm

[M. Lammers (martijnlammers)]

Sorry for the late response. I hope you managed to figure it out in the time I haven't responded. When I tested all of the scripts on my own virtual machine nothing seemed to be running into any errors.

The reason this might have occurred is due to you perhaps using the shellscript more than just once, which would append multiple json bodies to thesame file. That would explain the sudden extra bracket. This is something I should've taken into consideration. My apologies.

You can resolve this by either removing all the shell script files and starting over (Cause you might have appended to different files as well) or by checking each file and removing the duplicates.

} <--- remove anything above this
{
"private":true,...'

Since my reply, I've changed the original script, so it should now only append the json just one time, as it deletes any pre-existing file with thesame name before appending/creating package.json ensuring this error doesn't replicate itself anymore.