\#S:EXTERNAL=rust=hello_world.rs \#S:MODE=test,INCLUDE \#S:EXTERNAL=javascript=hello_world.js=test # Hello World The goal of this tutorial is to add an entry in Alice's instance and then retrieve that same entry in Bob's instance. ## Make your entry public So far the only entry you have had has been private. But this isn't that useful if you want your users to be able to share entries on the same network. Open up your `zomes/hello/code/src/lib.rs` file. Change the entry sharing to `Sharing::Public`: [![asciicast](https://asciinema.org/a/K0Vj50CIVNSYWr5RIbbrc6V3s.svg)](https://asciinema.org/a/K0Vj50CIVNSYWr5RIbbrc6V3s) ## Add Bob to the test Previously you made a test where Alice made a few zome calls and verified the results. Now, to test that the entries can be shared between agents on the same DNA, you can use Bob in your tests to interact with Alice. Open up your `test/index.js` file and add/update the following lines: Add `bob` to the scenario: ```diff - diorama.registerScenario("Test Hello Holo", async (s, t, { alice }) => { + diorama.registerScenario("Test Hello Holo", async (s, t, { alice, bob }) => { ``` Make the `retrieve_person` call with the result from `create_person`: \#S:HIDE,SKIP ```javascript console.log(create_result); ``` ```javascript const bob_retrieve_result = await bob.call("hello", "retrieve_person", {"address": create_result.Ok}); ``` Check that the result was Ok: ```javascript t.ok(bob_retrieve_result.Ok); ``` Check that the result does indeed match the person entry that Alice created: ```javascript t.deepEqual(bob_retrieve_result, { Ok: { App: [ 'person', '{"name":"Alice"}' ] }}) ``` \#S:HIDE ```javascript }) diorama.run() ``` Your test should look like this: \#S:CHECK=javascript=test ### Run the test Enter the nix-shell if you don't have it open already: ```bash nix-shell https://holochain.love ``` Now run the test and make sure it passes: ```bash nix-shell] hc test ``` ``` 1..7 # tests 7 # pass 7 # ok ``` ## Conductor Now it would be cool to see this happen for real outside of a test. Up till now you have only used `hc run` to run a single instance of a node. However, in order to have two separate instances communicate on one machine, we need to run `holochain` directly and pass it a config file. > #### Note > `hc` and `holochain` are both conductors that host your apps on your users' machines. `hc run` is for testing and development, and `holochain` is for end-users. It can host multiple instances of multiple DNAs for multiple users. Normally Alice and Bob would be running instances of your app in their own conductors on their own machines. But for the purposes of this tutorial, it'll be a lot more convenient to try this on one machine, so you don't have to worry about network setup. Before you can create the config file, you will need to generate some keys for your agents. Use `hc keygen` in your nix-shell to generate a key for each agent: ``` nix-shell] hc keygen -n ``` This will output something similar to the following: ``` Generating keystore (this will take a few moments)... Succesfully created new agent keystore. Public address: HcSCJhRioEqzvx9sooOfw6ANditrqdcxwfV7p7KP6extmnmzJIs83uKmfO9b8kz Keystore written to: /Users/user/Library/Preferences/org.holochain.holochain/keys/HcSCJhRioEqzvx9sooOfw6ANditrqdcxwfV7p7KP6extmnmzJIs83uKmfO9b8kz You can set this file in a conductor config as keystore_file for an agent. ``` Take note of the `Public address`; you will need it later. Copy the newly generated keystore to your working folder (replace the path with the one in the `Keystore written to: ` line from the output of the previous command): ```bash cp <path_of_generated_keystore> agent1.key ``` Now run `hc keygen` again but copy the key store to agent2.key: ```bash cp <path_of_generated_keystore> agent2.key ``` ### Config file Create a new file in the root directory of your project called `conductor-config.toml`. Add an agent with ID `test_agent1` and name it `Agent 1`: ```toml # ----------- Agents ----------- [[agents]] id = "test_agent1" name = "Agent 1" ``` Use the public address and keystore from `hc keygen` that you made for agent 1 before here: ```toml public_address = "<public_address_of_agent_1>" keystore_file = "./agent1.key" ``` Add an agent with ID `test_agent2` and name it `Agent 2`: ```toml [[agents]] id = "test_agent2" name = "Agent 2" ``` Use the public address and keystore from `hc keygen` that you made for agent 2 before here: ```toml public_address = "<public_address_of_agent_2>" keystore_file = "./agent2.key" ``` Package your DNA and take note of its hash: ``` nix-shell] hc package ``` You will see something similar to this: ``` DNA hash: QmS7wUJj6XZR1SBVk1idGh6bK8gN6RNSFXP2GoC8yCJUzn ``` Add the DNA to your config file with ID `hello` and the hash you just saw above: ```toml # ----------- DNAs ----------- [[dnas]] id = "hello" file = "dist/hello_holo.dna.json" hash = "<dna_hash>" ``` Connect agent 1 to the `hello` DNA to create an instance for Alice: ```toml [[instances]] id = "Alice" dna = "hello" agent = "test_agent1" [instances.storage] type = "memory" ``` Add the Bob instance with the same `hello` dna: ```toml [[instances]] id = "Bob" dna = "hello" agent = "test_agent2" [instances.storage] type = "memory" ``` Setup the WebSocket interface on socket `3041`: ```toml [[interfaces]] id = "websocket_interface" [interfaces.driver] type = "websocket" port = 3401 ``` Add your instances to this interface so you can call their zome functions: ```toml [[interfaces.instances]] id = "Alice" [[interfaces.instances]] id = "Bob" ``` > #### Note > Again, in real life Alice and Bob would each have their own conductor, so they wouldn't be listening on the same WebSocket interface. ## Allow the users to choose their instance Before you can use two agents, you need a way for the UI to specify which instance the user wants to use. You can do this by setting the instance ID in the zome call. You can think of an instance as a running version of a DNA, in the same way that a variable is an instance of a struct. Open the `gui/index.html` file. Add a text box for your users to set the agent ID: ```html <input type="text" id="instance" placeholder="Enter your instance ID"><br> ``` Open the `gui/index.js` and do the following for every `callZome` call: [![asciicast](https://asciinema.org/a/Tp2xSDERlohFXy90LP7Yu4HQR.svg)](https://asciinema.org/a/Tp2xSDERlohFXy90LP7Yu4HQR) ## Run the app and two UIs Now the fun part, where you get to play with what you just wrote. Open up three terminal windows and enter the nix-shell in each one: ```bash nix-shell https://holochain.love ``` #### Terminal one Go to the root folder of your app: ``` nix-shell] cd /path/to/my/app ``` Start by running the conductor. It's a bit different this time; instead of `hc run` you will use `holochain` directly: ``` nix-shell] holochain -c conductor-config.toml ``` #### Terminal two Go to the root folder of your GUI: ``` nix-shell] cd /path/to/my/gui ``` Run a GUI on port `8000`: ``` nix-shell] python -m SimpleHTTPServer 8000 ``` #### Terminal three Go to the root folder of your GUI: ``` nix-shell] cd /path/to/my/gui ``` Run a GUI on port `8001`: ``` nix-shell] python -m SimpleHTTPServer 8001 ``` ### Open up the browser Open two tabs. #### Tab one Go to ``. Enter `Alice` into the `Enter your instance ID` text box. #### Tab two Go to ``. Enter `Bob` into the `Enter your instance ID` text box. #### Tab one --- Alice Create a person entry with your name: ![](https://i.imgur.com/6PEDn6y.png) #### Tab two --- Bob Copy the address from the Alice tab and retrieve the person entry: ![](https://i.imgur.com/ps9RBr2.png) Hooray! Alice and Bob are now able to find each other's information on the DHT