Implement memory resource granting and revocation functionality for components

[Copilot]

This PR implements comprehensive memory resource management functionality that allows administrators to both grant and revoke memory limits for WebAssembly components using Kubernetes-style memory specifications. The implementation maps policy file memory limits to Wasmtime's StoreLimitsBuilder API.

Key Features

• Grant memory permissions: Components can receive memory limits via the grant_permission API:

  manager.grant_permission("my-component", "resource", &serde_json::json!({
      "memory": "512Mi" 
  })).await?;

• Revoke memory permissions: Components can have memory limits removed via the revoke_permission API:

  manager.revoke_permission("my-component", "resource", &serde_json::json!({
      "memory": "512Mi" 
  })).await?;

• Kubernetes-style memory limits: Supports standard k8s memory format with suffixes:

  • "512Mi" - 512 mebibytes
  • "1Gi" - 1 gibibyte
  • "256Ki" - 256 kibibytes
  • "1024" - raw bytes

• Policy integration: Memory limits are stored in policy documents and parsed into the WASI state template:

  permissions:
    resources:
      limits:
        memory: "512Mi"

Implementation Details

• Extended policy parsing: Added "resource" permission type to both grant_permission and revoke_permission methods
• Memory limit extraction: New extract_memory_limit function converts k8s-style strings to bytes
• WASI state integration: Memory limits flow from policy → WasiStateTemplate → WasiState
• Wasmtime integration: Custom ResourceLimiter implementation wraps StoreLimits for proper trait compatibility
• Memory revocation: New remove_resource_permission_from_policy function removes memory limits from policies
• Backward compatibility: Maintains support for legacy numeric memory values

Testing

Added comprehensive test coverage including:

• Memory limit parsing and conversion
• Resource permission granting and revoking through the policy system
• End-to-end policy → WASI state → resource limiter flow
• Edge cases and error handling for both grant and revoke operations

The implementation provides complete memory resource management while maintaining the project's principles of minimal, surgical changes.

Fixes #171.

---

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[github-actions]

🔍 Security Audit Warnings

The cargo audit security scan found 1 warning(s) in dependencies:

Click to view cargo audit output

�[0m�[0m�[1m�[32m    Fetching�[0m advisory database from `https://github.com/RustSec/advisory-db.git`
�[0m�[0m�[1m�[32m      Loaded�[0m 796 security advisories (from /home/runner/.cargo/advisory-db)
�[0m�[0m�[1m�[32m    Updating�[0m crates.io index
�[0m�[0m�[1m�[32m    Scanning�[0m Cargo.lock for vulnerabilities (529 crate dependencies)
�[0m�[0m�[1m�[33mCrate:    �[0m paste
�[0m�[0m�[1m�[33mVersion:  �[0m 1.0.15
�[0m�[0m�[1m�[33mWarning:  �[0m unmaintained
�[0m�[0m�[1m�[33mTitle:    �[0m paste - no longer maintained
�[0m�[0m�[1m�[33mDate:     �[0m 2024-10-07
�[0m�[0m�[1m�[33mID:       �[0m RUSTSEC-2024-0436
�[0m�[0m�[1m�[33mURL:      �[0m https://rustsec.org/advisories/RUSTSEC-2024-0436
�[0m�[0m�[1m�[33mDependency tree:
�[0mpaste 1.0.15
└── rmcp 0.2.1
    ├── wassette-mcp-server 0.2.0
    └── mcp-server 0.1.0
        └── wassette-mcp-server 0.2.0

�[0m�[0m�[1m�[33mwarning:�[0m 1 allowed warning found

These are warnings (not vulnerabilities) but should be reviewed for:

• Unmaintained crates - consider finding maintained alternatives
• Known issues - check if they affect your use case
• Supply chain risks - evaluate dependency hygiene

The security job will continue to pass as these are warnings, not blocking security issues.

[Mossaka]

@copilot could you please fix the following build error?

error[E0599]: no method named `set_limiter` found for struct `Store` in the current scope
Error:    --> crates/wassette/src/lib.rs:490:19
    |
490 |             store.set_limiter(limiter);
    |                   ^^^^^^^^^^^
    |
help: there is a method `limiter` with a similar name
    |
490 -             store.set_limiter(limiter);
490 +             store.limiter(limiter);
    |

For more information about this error, try `rustc --explain E0599`.
error: could not compile `wassette` (lib) due to 1 previous error
error: Recipe `build` failed on line 7 with exit code 101
Error: Process completed with exit code 101.

[Copilot]

@copilot could you please fix the following build error?

...

Fixed! The build error was caused by using a non-existent set_limiter() method on Wasmtime's Store. Replaced it with the correct limiter() API that accepts a closure to extract the ResourceLimiter from the WasiState. Memory limits now flow properly from policy → WasiStateTemplate → WasiState → Store. (commit ee252eb)

[github-actions]

🔍 Security Audit Warnings

The cargo audit security scan found 1 warning(s) in dependencies:

Click to view cargo audit output

�[0m�[0m�[1m�[32m    Fetching�[0m advisory database from `https://github.com/RustSec/advisory-db.git`
�[0m�[0m�[1m�[32m      Loaded�[0m 796 security advisories (from /home/runner/.cargo/advisory-db)
�[0m�[0m�[1m�[32m    Updating�[0m crates.io index
�[0m�[0m�[1m�[32m    Scanning�[0m Cargo.lock for vulnerabilities (529 crate dependencies)
�[0m�[0m�[1m�[33mCrate:    �[0m paste
�[0m�[0m�[1m�[33mVersion:  �[0m 1.0.15
�[0m�[0m�[1m�[33mWarning:  �[0m unmaintained
�[0m�[0m�[1m�[33mTitle:    �[0m paste - no longer maintained
�[0m�[0m�[1m�[33mDate:     �[0m 2024-10-07
�[0m�[0m�[1m�[33mID:       �[0m RUSTSEC-2024-0436
�[0m�[0m�[1m�[33mURL:      �[0m https://rustsec.org/advisories/RUSTSEC-2024-0436
�[0m�[0m�[1m�[33mDependency tree:
�[0mpaste 1.0.15
└── rmcp 0.2.1
    ├── wassette-mcp-server 0.2.0
    └── mcp-server 0.1.0
        └── wassette-mcp-server 0.2.0

�[0m�[0m�[1m�[33mwarning:�[0m 1 allowed warning found

These are warnings (not vulnerabilities) but should be reviewed for:

• Unmaintained crates - consider finding maintained alternatives
• Known issues - check if they affect your use case
• Supply chain risks - evaluate dependency hygiene

The security job will continue to pass as these are warnings, not blocking security issues.

[github-actions]

🔍 Security Audit Warnings

The cargo audit security scan found 1 warning(s) in dependencies:

Click to view cargo audit output

�[0m�[0m�[1m�[32m    Fetching�[0m advisory database from `https://github.com/RustSec/advisory-db.git`
�[0m�[0m�[1m�[32m      Loaded�[0m 796 security advisories (from /home/runner/.cargo/advisory-db)
�[0m�[0m�[1m�[32m    Updating�[0m crates.io index
�[0m�[0m�[1m�[32m    Scanning�[0m Cargo.lock for vulnerabilities (529 crate dependencies)
�[0m�[0m�[1m�[33mCrate:    �[0m paste
�[0m�[0m�[1m�[33mVersion:  �[0m 1.0.15
�[0m�[0m�[1m�[33mWarning:  �[0m unmaintained
�[0m�[0m�[1m�[33mTitle:    �[0m paste - no longer maintained
�[0m�[0m�[1m�[33mDate:     �[0m 2024-10-07
�[0m�[0m�[1m�[33mID:       �[0m RUSTSEC-2024-0436
�[0m�[0m�[1m�[33mURL:      �[0m https://rustsec.org/advisories/RUSTSEC-2024-0436
�[0m�[0m�[1m�[33mDependency tree:
�[0mpaste 1.0.15
└── rmcp 0.2.1
    ├── wassette-mcp-server 0.2.0
    └── mcp-server 0.1.0
        └── wassette-mcp-server 0.2.0

�[0m�[0m�[1m�[33mwarning:�[0m 1 allowed warning found

These are warnings (not vulnerabilities) but should be reviewed for:

• Unmaintained crates - consider finding maintained alternatives
• Known issues - check if they affect your use case
• Supply chain risks - evaluate dependency hygiene

The security job will continue to pass as these are warnings, not blocking security issues.

[Mossaka]

@copilot can you please add the revoke permission for memory

[Copilot]

@copilot can you please add the revoke permission for memory

Implemented memory resource revocation functionality! The revoke_permission method now supports "resource" type permissions to remove memory limits from component policies. Components can revoke memory limits like this:

manager.revoke_permission("my-component", "resource", &serde_json::json!({
    "memory": "512Mi" 
})).await?;

The implementation includes comprehensive test coverage and proper cleanup of policy structures. (commit 94ceccc)

[Mossaka]

@copilot could you please fix these test failiures?

error[E0061]: this function takes 3 arguments but 2 arguments were supplied
Error:    --> crates/wassette/src/wasistate.rs:737:24
    |
737 |         let template = create_wasi_state_template_from_policy(&policy, plugin_dir).unwrap();
    |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^--------------------- argument #3 of type `&std::collections::HashMap<std::string::String, std::string::String>` is missing
    |
note: function defined here
   --> crates/wassette/src/wasistate.rs:176:8
    |
176 | pub fn create_wasi_state_template_from_policy(
    |        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
...
179 |     environment_vars: &HashMap<String, String>,
    |     ------------------------------------------
help: provide the argument
    |
737 |         let template = create_wasi_state_template_from_policy(&policy, plugin_dir, /* &std::collections::HashMap<std::string::String, std::string::String> */).unwrap();
    |                                                                                  ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

error[E0061]: this function takes 3 arguments but 2 arguments were supplied
Error:    --> crates/wassette/src/wasistate.rs:764:24
    |
764 |         let template = create_wasi_state_template_from_policy(&policy, plugin_dir).unwrap();
    |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^--------------------- argument #3 of type `&std::collections::HashMap<std::string::String, std::string::String>` is missing
    |
note: function defined here
   --> crates/wassette/src/wasistate.rs:176:8
    |
176 | pub fn create_wasi_state_template_from_policy(
    |        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
...
179 |     environment_vars: &HashMap<String, String>,
    |     ------------------------------------------
help: provide the argument
    |
764 |         let template = create_wasi_state_template_from_policy(&policy, plugin_dir, /* &std::collections::HashMap<std::string::String, std::string::String> */).unwrap();
    |                                                                                  ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

For more information about this error, try `rustc --explain E0061`.
error: could not compile `wassette` (lib test) due to 2 previous errors
warning: build failed, waiting for other jobs to finish...
error: Recipe `test` failed on line 2 with exit code 101
Error: Process completed with exit code 101.

[Copilot]

@copilot could you please fix these test failiures?

...

Fixed! The test compilation errors were caused by missing the third environment_vars parameter that was added to the create_wasi_state_template_from_policy function. Added the missing &HashMap::new() parameter to both failing test functions. Both tests now compile and pass successfully. (commit 170ca51)