feat: chat ffi (#5349)

Description
---
Create an FFI wrapper for a simple chat client


Motivation and Context
---
So we can chat on mobile and other non rust platforms.

How Has This Been Tested?
---
Cucumber

What process can a PR reviewer use to test or verify this change?
---
Review the cucumber tests as well

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Breaking Changes
---

- [x] None
- [ ] Requires data directory on base node to be deleted
- [ ] Requires hard fork
- [ ] Other - Please specify

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---------

Co-authored-by: SW van Heerden <swvheerden@gmail.com>

.github/workflows/integration_tests.yml

@@ -98,7 +98,7 @@ jobs:
             --all-features
             --release
             --package tari_integration_tests
-            -- -t "${{ env.CI_PROFILE }} and (not @wallet-ffi) and (not @broken)"
+            -- -t "${{ env.CI_PROFILE }} and (not @wallet-ffi) and (not @chat-ffi) and (not @broken)"
             -c 5
             --retry 2
 
@@ -167,6 +167,6 @@ jobs:
             --all-features
             --release
             --package tari_integration_tests
-            -- -t "@wallet-ffi and ${{ env.CI_PROFILE }} and (not @broken)"
+            -- -t "(@wallet-ffi or @chat-ffi) and ${{ env.CI_PROFILE }} and (not @broken)"
             -c 1
             --retry 2

Cargo.toml

@@ -1,6 +1,7 @@
 [workspace]
 
 members = [
+    "base_layer/chat_ffi",
     "base_layer/core",
     "base_layer/common_types",
     "base_layer/contacts",

base_layer/chat_ffi/Cargo.toml

@@ -0,0 +1,31 @@
+[package]
+name = "tari_chat_ffi"
+authors = ["The Tari Development Community"]
+description = "Tari cryptocurrency chat C FFI bindings"
+license = "BSD-3-Clause"
+version = "0.50.0-pre.0"
+edition = "2018"
+
+[dependencies]
+tari_chat_client = { path = "../contacts/examples/chat_client" }
+tari_common = { path = "../../common" }
+tari_common_types = { path = "../common_types" }
+tari_comms = { path = "../../comms/core" }
+tari_contacts = { path = "../contacts" }
+tari_p2p = { path = "../p2p" }
+
+libc = "0.2.65"
+log = "0.4.6"
+serde_json = "1.0.64"
+thiserror = "1.0.26"
+tokio = "1.23"
+
+[target.'cfg(target_os="android")'.dependencies]
+openssl = { version = "0.10.48", features = ["vendored"] }
+
+[lib]
+crate-type = ["staticlib","cdylib"]
+
+[build-dependencies]
+cbindgen = "0.24.3"
+tari_common = { path = "../../common", features = ["build", "static-application-info"] }

base_layer/chat_ffi/README.md

@@ -0,0 +1,7 @@
+# Tari Chat FFI
+
+Foreign Function interface for the Tari Android and Tari iOS Chat interface.
+
+This crate is part of the [Tari Cryptocurrency](https://tari.com) project.
+
+TODO

base_layer/chat_ffi/build.rs

@@ -0,0 +1,47 @@
+// Copyright 2023. The Tari Project
+// SPDX-License-Identifier: BSD-3-Clause
+
+use std::{env, path::PathBuf};
+
+use cbindgen::{Config, ExportConfig, Language, ParseConfig, Style};
+use tari_common::build::StaticApplicationInfo;
+
+fn main() {
+    let crate_dir = env::var("CARGO_MANIFEST_DIR").unwrap();
+
+    // generate version info
+    let gen = StaticApplicationInfo::initialize().unwrap();
+    gen.write_consts_to_outdir("consts.rs").unwrap();
+
+    // let package_name = env::var("CARGO_PKG_NAME").unwrap();
+    let output_file = PathBuf::from(&crate_dir).join("chat.h").display().to_string();
+
+    let config = Config {
+        language: Language::C,
+        header: Some("// Copyright 2023. The Tari Project\n// SPDX-License-Identifier: BSD-3-Clause".to_string()),
+        parse: ParseConfig {
+            parse_deps: true,
+            include: Some(vec![
+                "tari_core".to_string(),
+                "tari_common_types".to_string(),
+                "tari_crypto".to_string(),
+                "tari_p2p".to_string(),
+                "tari_wallet".to_string(),
+                "tari_contacts".to_string(),
+            ]),
+            ..Default::default()
+        },
+        autogen_warning: Some("// This file was generated by cargo-bindgen. Please do not edit manually.".to_string()),
+        style: Style::Tag,
+        cpp_compat: true,
+        export: ExportConfig {
+            include: vec!["TariUtxo".to_string()],
+            ..Default::default()
+        },
+        ..Default::default()
+    };
+
+    cbindgen::generate_with_config(&crate_dir, config)
+        .unwrap()
+        .write_to_file(output_file);
+}

base_layer/chat_ffi/chat.h

@@ -0,0 +1,186 @@
+// Copyright 2023. The Tari Project
+// SPDX-License-Identifier: BSD-3-Clause
+
+// This file was generated by cargo-bindgen. Please do not edit manually.
+
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+struct ChatMessages;
+
+struct ClientFFI;
+
+struct ClientPeers;
+
+/**
+ * Configuration for a comms node
+ */
+struct P2pConfig;
+
+struct TariAddress;
+
+#ifdef __cplusplus
+extern "C" {
+#endif // __cplusplus
+
+/**
+ * Creates a Chat Client
+ * TODO: This function takes a ptr to a collection of seed peers and this works fine in cucumber, or native rust but
+ * isn't at all ideal for a real FFI. We need to work with the mobile teams and come up with a better interface
+ * for supplying seed peers.
+ *
+ * ## Arguments
+ * `config` - The P2PConfig pointer
+ * `identity_file_path` - The path to the node identity file
+ * `db_path` - The path to the db file
+ * `seed_peers` - A ptr to a collection of seed peers
+ * `network_str` - The network to connect to
+ * `error_out` - Pointer to an int which will be modified
+ *
+ * ## Returns
+ * `*mut ChatClient` - Returns a pointer to a ChatClient, note that it returns ptr::null_mut()
+ * if any error was encountered or if the runtime could not be created.
+ *
+ * # Safety
+ * The ```destroy_client``` method must be called when finished with a ClientFFI to prevent a memory leak
+ */
+struct ClientFFI *create_chat_client(struct P2pConfig *config,
+                                     const char *identity_file_path,
+                                     const char *db_path,
+                                     struct ClientPeers *seed_peers,
+                                     const char *network_str,
+                                     int *error_out);
+
+/**
+ * Frees memory for a ClientFFI
+ *
+ * ## Arguments
+ * `client` - The pointer of a ClientFFI
+ *
+ * ## Returns
+ * `()` - Does not return a value, equivalent to void in C
+ *
+ * # Safety
+ * None
+ */
+void destroy_client_ffi(struct ClientFFI *client);
+
+/**
+ * Sends a message over a client
+ *
+ * ## Arguments
+ * `client` - The Client pointer
+ * `receiver` - A string containing a tari address
+ * `message` - The peer seeds config for the node
+ * `error_out` - Pointer to an int which will be modified
+ *
+ * ## Returns
+ * `()` - Does not return a value, equivalent to void in C
+ *
+ * # Safety
+ * The ```receiver``` should be destroyed after use
+ */
+void send_message(struct ClientFFI *client,
+                  struct TariAddress *receiver,
+                  const char *message_c_char,
+                  int *error_out);
+
+/**
+ * Add a contact
+ *
+ * ## Arguments
+ * `client` - The Client pointer
+ * `address` - A TariAddress ptr
+ * `error_out` - Pointer to an int which will be modified
+ *
+ * ## Returns
+ * `()` - Does not return a value, equivalent to void in C
+ *
+ * # Safety
+ * The ```address``` should be destroyed after use
+ */
+void add_contact(struct ClientFFI *client, struct TariAddress *receiver, int *error_out);
+
+/**
+ * Check the online status of a contact
+ *
+ * ## Arguments
+ * `client` - The Client pointer
+ * `address` - A TariAddress ptr
+ * `error_out` - Pointer to an int which will be modified
+ *
+ * ## Returns
+ * `()` - Does not return a value, equivalent to void in C
+ *
+ * # Safety
+ * The ```address``` should be destroyed after use
+ */
+int check_online_status(struct ClientFFI *client, struct TariAddress *receiver, int *error_out);
+
+/**
+ * Get a ptr to all messages from or to address
+ *
+ * ## Arguments
+ * `client` - The Client pointer
+ * `address` - A TariAddress ptr
+ * `error_out` - Pointer to an int which will be modified
+ *
+ * ## Returns
+ * `()` - Does not return a value, equivalent to void in C
+ *
+ * # Safety
+ * The ```address``` should be destroyed after use
+ * The returned pointer to ```*mut ChatMessages``` should be destroyed after use
+ */
+struct ChatMessages *get_all_messages(struct ClientFFI *client,
+                                      struct TariAddress *address,
+                                      int *error_out);
+
+/**
+ * Frees memory for messages
+ *
+ * ## Arguments
+ * `messages_ptr` - The pointer of a Vec<Message>
+ *
+ * ## Returns
+ * `()` - Does not return a value, equivalent to void in C
+ *
+ * # Safety
+ * None
+ */
+void destroy_messages(struct ChatMessages *messages_ptr);
+
+/**
+ * Creates a TariAddress and returns a ptr
+ *
+ * ## Arguments
+ * `receiver_c_char` - A string containing a tari address hex value
+ * `error_out` - Pointer to an int which will be modified
+ *
+ * ## Returns
+ * `*mut TariAddress` - A ptr to a TariAddress
+ *
+ * # Safety
+ * The ```destroy_tari_address``` function should be called when finished with the TariAddress
+ */
+struct TariAddress *create_tari_address(const char *receiver_c_char, int *error_out);
+
+/**
+ * Frees memory for a TariAddress
+ *
+ * ## Arguments
+ * `address` - The pointer of a TariAddress
+ *
+ * ## Returns
+ * `()` - Does not return a value, equivalent to void in C
+ *
+ * # Safety
+ * None
+ */
+void destroy_tari_address(struct TariAddress *address);
+
+#ifdef __cplusplus
+} // extern "C"
+#endif // __cplusplus