hcrolesmixin

Generic holochain mixin to include administrator and dynamic roles in any holochain application, using the progenitor pattern.

This mixin is built to target hc v0.0.42-alpha3. It also depends on the holochain_anchors to be present and configured.

Design

Here is the design for this mixin: https://hackmd.io/6xfwfSVYSGeZe3vQ_-1cWw?view.

Installation

Add the following to your zomes cargo toml.

holochain_anchors = "0.2.1" hc_roles_mixin = "0.1.1"

Usage

Setup

Add the anchor entry definition to your zome.

rust #[entry_def] fn anchor_def() -> ValidatingEntryType { holochain_anchors::anchor_definition() }

Add the roles entry definition to your zome.

rust #[entry_def] fn roles_def() -> ValidatingEntryType { hc_roles_mixin::role_entry_def() }

In your init function, create the Admin role:

```rust

[init]

fn init() { hcrolesmixin::handlers::createadminrole()?; Ok(()) } ```

Create a role

To create a role, simply call the create_role function:

```rust

[zomefn("hcpublic")]

fn somepublicfunction() { let myrolename = String::from("editor");

hc_roles_mixin::handlers::create_role(&my_role_name)?;
...

} ```

Assign a role

To assign a role, simply call the assign_role function:

```rust

[zomefn("hcpublic")]

fn someotherpublicfunction(agentaddress: Address) { let myrolename = String::from("editor");

hc_roles_mixin::handlers::assign_role(&my_role_name, &agent_address)?;
...

} ```

Check if user has a certain role

To check if a user has a certain role, you can use the validation has_agent_role function:

```rust validation: | validationdata: hdk::EntryValidationData| { match validationdata { hdk::EntryValidationData::Create { entry, validationdata } => { let agentaddress = &validationdata.sources()[0]; let isagentpermittedtocreatethisentry = hcrolesmixin::validaton::hasagentrole(&agentaddress, String::from("editor"))?;

        if !is_agent_permitted_to_create_this_entry {
            return Err(String::from("Only editors can create a new entry"));
        }
        ...

```

Unassign a role

To unassign a role, simply call the unassign_role function:

```rust

[zomefn("hcpublic")]

fn someotherpublicfunction(agentaddress: Address) { let myrolename = String::from("editor");

hc_roles_mixin::handlers::unassign_role(&my_role_name, &agent_address)?;
...

} ```