Files
nana-story/crates/nana-store/src/lib.rs
T

1092 lines
36 KiB
Rust

use std::{
collections::BTreeMap,
path::Path,
sync::{Mutex, MutexGuard},
};
use nana_domain::{RuntimeState, StoryNode, stable_json_hash};
use rusqlite::{params, Connection, OptionalExtension, TransactionBehavior};
use thiserror::Error;
#[derive(Debug, Error, PartialEq, Eq)]
pub enum StoreError {
#[error("story not found: {0}")]
StoryNotFound(String),
#[error("branch not found: {story_id}/{branch_id}")]
BranchNotFound { story_id: String, branch_id: String },
#[error("node already exists: {0}")]
NodeAlreadyExists(String),
#[error("parent node not found: {0}")]
ParentNotFound(String),
#[error("branch head changed: expected {expected}, got {actual}")]
StaleBranchHead { expected: String, actual: String },
#[error("node and materialized state disagree: {0}")]
StateMismatch(&'static str),
#[error("materialized state hash does not match node: {node_id}")]
StateHashMismatch { node_id: String },
#[error("sqlite storage error: {0}")]
Sqlite(String),
#[error("JSON serialization error: {0}")]
Serialization(String),
#[error("storage lock is poisoned")]
Poisoned,
}
impl From<rusqlite::Error> for StoreError {
fn from(error: rusqlite::Error) -> Self {
Self::Sqlite(error.to_string())
}
}
impl From<serde_json::Error> for StoreError {
fn from(error: serde_json::Error) -> Self {
Self::Serialization(error.to_string())
}
}
pub trait StoryStore: Send + Sync {
fn append_node(&self, node: &StoryNode, state: &RuntimeState) -> Result<(), StoreError>;
fn load_state(&self, story_id: &str, branch_id: &str) -> Result<RuntimeState, StoreError>;
fn load_node(&self, story_id: &str, node_id: &str) -> Result<StoryNode, StoreError>;
}
#[derive(Debug, Default)]
struct MemoryData {
nodes: BTreeMap<(String, String), StoryNode>,
states: BTreeMap<(String, String), RuntimeState>,
branch_heads: BTreeMap<(String, String), String>,
}
/// Deterministic test and development store.
///
/// Production persistence will implement the same append-only semantics with
/// SQLite. Keeping this implementation in the crate lets the engine/runtime
/// integration tests exercise branch rules without depending on a database.
#[derive(Debug, Default)]
pub struct InMemoryStoryStore {
data: Mutex<MemoryData>,
}
impl InMemoryStoryStore {
#[must_use]
pub fn new() -> Self {
Self::default()
}
pub fn branch_head(
&self,
story_id: &str,
branch_id: &str,
) -> Result<Option<String>, StoreError> {
let data = self.lock()?;
Ok(data
.branch_heads
.get(&(story_id.to_owned(), branch_id.to_owned()))
.cloned())
}
pub fn load_state_at_node(
&self,
story_id: &str,
node_id: &str,
) -> Result<RuntimeState, StoreError> {
let data = self.lock()?;
data.states
.get(&(story_id.to_owned(), node_id.to_owned()))
.cloned()
.ok_or_else(|| StoreError::ParentNotFound(node_id.to_owned()))
}
fn lock(&self) -> Result<MutexGuard<'_, MemoryData>, StoreError> {
self.data.lock().map_err(|_| StoreError::Poisoned)
}
}
impl StoryStore for InMemoryStoryStore {
fn append_node(&self, node: &StoryNode, state: &RuntimeState) -> Result<(), StoreError> {
validate_materialized_state(node, state)?;
let node_key = (node.story_id.clone(), node.id.clone());
let branch_key = (node.story_id.clone(), node.branch_id.clone());
let mut data = self.lock()?;
if data.nodes.contains_key(&node_key) {
return Err(StoreError::NodeAlreadyExists(node.id.clone()));
}
if let Some(parent_id) = &node.parent_id {
if !data
.nodes
.contains_key(&(node.story_id.clone(), parent_id.clone()))
{
return Err(StoreError::ParentNotFound(parent_id.clone()));
}
} else if data
.nodes
.keys()
.any(|(story_id, _)| story_id == &node.story_id)
{
return Err(StoreError::ParentNotFound(
"a non-root node must name its parent".to_owned(),
));
}
if let Some(current_head) = data.branch_heads.get(&branch_key) {
let expected_parent = node.parent_id.as_deref().unwrap_or("<none>");
if current_head != expected_parent {
return Err(StoreError::StaleBranchHead {
expected: current_head.clone(),
actual: expected_parent.to_owned(),
});
}
}
// All validation happens before any map is changed. This mirrors the
// all-or-nothing transaction boundary required from the SQLite store.
data.nodes.insert(node_key.clone(), node.clone());
data.states.insert(node_key, state.clone());
data.branch_heads.insert(branch_key, node.id.clone());
Ok(())
}
fn load_state(&self, story_id: &str, branch_id: &str) -> Result<RuntimeState, StoreError> {
let data = self.lock()?;
let story_exists = data
.nodes
.keys()
.any(|(stored_story_id, _)| stored_story_id == story_id);
if !story_exists {
return Err(StoreError::StoryNotFound(story_id.to_owned()));
}
let head = data
.branch_heads
.get(&(story_id.to_owned(), branch_id.to_owned()))
.ok_or_else(|| StoreError::BranchNotFound {
story_id: story_id.to_owned(),
branch_id: branch_id.to_owned(),
})?;
data.states
.get(&(story_id.to_owned(), head.clone()))
.cloned()
.ok_or(StoreError::StateMismatch("branch head has no state"))
}
fn load_node(&self, story_id: &str, node_id: &str) -> Result<StoryNode, StoreError> {
let data = self.lock()?;
data.nodes
.get(&(story_id.to_owned(), node_id.to_owned()))
.cloned()
.ok_or_else(|| StoreError::ParentNotFound(node_id.to_owned()))
}
}
/// Durable SQLite implementation of the append-only story store.
///
/// A connection is kept behind a mutex so one store value preserves the same
/// `Send + Sync` contract as the in-memory implementation. SQLite still
/// provides the cross-connection transaction boundary when a database is
/// reopened or shared by multiple store values.
pub struct SqliteStoryStore {
connection: Mutex<Connection>,
}
impl SqliteStoryStore {
/// Opens or creates a story database at `path`.
pub fn open(path: impl AsRef<Path>) -> Result<Self, StoreError> {
let connection = Connection::open(path)?;
Self::from_connection(connection)
}
/// Opens a fresh in-memory story database.
pub fn open_in_memory() -> Result<Self, StoreError> {
let connection = Connection::open_in_memory()?;
Self::from_connection(connection)
}
/// Returns the current head node for a branch, if the branch exists.
pub fn branch_head(
&self,
story_id: &str,
branch_id: &str,
) -> Result<Option<String>, StoreError> {
let connection = self.lock()?;
connection
.query_row(
"SELECT head_node_id
FROM branch_heads
WHERE story_id = ?1 AND branch_id = ?2",
params![story_id, branch_id],
|row| row.get(0),
)
.optional()
.map_err(StoreError::from)
}
/// Loads the materialized state associated with a specific node.
pub fn load_state_at_node(
&self,
story_id: &str,
node_id: &str,
) -> Result<RuntimeState, StoreError> {
let connection = self.lock()?;
let stored = connection
.query_row(
"SELECT nodes.branch_id, nodes.parent_id, nodes.node_json,
materialized_states.state_json
FROM nodes
LEFT JOIN materialized_states
ON materialized_states.story_id = nodes.story_id
AND materialized_states.node_id = nodes.node_id
WHERE nodes.story_id = ?1 AND nodes.node_id = ?2",
params![story_id, node_id],
|row| {
Ok((
row.get::<_, String>(0)?,
row.get::<_, Option<String>>(1)?,
row.get::<_, String>(2)?,
row.get::<_, Option<String>>(3)?,
))
},
)
.optional()?
.ok_or_else(|| StoreError::ParentNotFound(node_id.to_owned()))?;
let node = deserialize_node(&stored.2)?;
validate_loaded_node(&node, story_id, node_id, &stored.0, stored.1.as_deref())?;
let state_json = stored
.3
.ok_or(StoreError::StateMismatch("node has no materialized state"))?;
let state = deserialize_state(&state_json)?;
validate_loaded_state(&state, story_id, node_id, &stored.0)?;
validate_state_hash(&node, &state)?;
Ok(state)
}
fn from_connection(connection: Connection) -> Result<Self, StoreError> {
initialize_schema(&connection)?;
Ok(Self {
connection: Mutex::new(connection),
})
}
fn lock(&self) -> Result<MutexGuard<'_, Connection>, StoreError> {
self.connection.lock().map_err(|_| StoreError::Poisoned)
}
}
impl StoryStore for SqliteStoryStore {
fn append_node(&self, node: &StoryNode, state: &RuntimeState) -> Result<(), StoreError> {
validate_materialized_state(node, state)?;
let node_json = serde_json::to_string(node)?;
let state_json = serde_json::to_string(state)?;
let mut connection = self.lock()?;
let transaction =
connection.transaction_with_behavior(TransactionBehavior::Immediate)?;
let node_exists = transaction.query_row(
"SELECT EXISTS(
SELECT 1 FROM nodes WHERE story_id = ?1 AND node_id = ?2
)",
params![node.story_id, node.id],
|row| row.get::<_, bool>(0),
)?;
if node_exists {
return Err(StoreError::NodeAlreadyExists(node.id.clone()));
}
if let Some(parent_id) = &node.parent_id {
let parent_exists = transaction.query_row(
"SELECT EXISTS(
SELECT 1 FROM nodes WHERE story_id = ?1 AND node_id = ?2
)",
params![node.story_id, parent_id],
|row| row.get::<_, bool>(0),
)?;
if !parent_exists {
return Err(StoreError::ParentNotFound(parent_id.clone()));
}
} else {
let story_exists = transaction.query_row(
"SELECT EXISTS(SELECT 1 FROM nodes WHERE story_id = ?1)",
params![node.story_id],
|row| row.get::<_, bool>(0),
)?;
if story_exists {
return Err(StoreError::ParentNotFound(
"a non-root node must name its parent".to_owned(),
));
}
}
let current_head = transaction
.query_row(
"SELECT head_node_id
FROM branch_heads
WHERE story_id = ?1 AND branch_id = ?2",
params![node.story_id, node.branch_id],
|row| row.get::<_, String>(0),
)
.optional()?;
if let Some(current_head) = current_head {
let expected_parent = node.parent_id.as_deref().unwrap_or("<none>");
if current_head != expected_parent {
return Err(StoreError::StaleBranchHead {
expected: current_head,
actual: expected_parent.to_owned(),
});
}
}
transaction.execute(
"INSERT INTO nodes (
story_id, node_id, branch_id, parent_id, node_json
) VALUES (?1, ?2, ?3, ?4, ?5)",
params![
node.story_id,
node.id,
node.branch_id,
node.parent_id,
node_json
],
)?;
transaction.execute(
"INSERT INTO materialized_states (story_id, node_id, state_json)
VALUES (?1, ?2, ?3)",
params![node.story_id, node.id, state_json],
)?;
transaction.execute(
"INSERT INTO branch_heads (story_id, branch_id, head_node_id)
VALUES (?1, ?2, ?3)
ON CONFLICT(story_id, branch_id)
DO UPDATE SET head_node_id = excluded.head_node_id",
params![node.story_id, node.branch_id, node.id],
)?;
transaction.commit()?;
Ok(())
}
fn load_state(&self, story_id: &str, branch_id: &str) -> Result<RuntimeState, StoreError> {
let connection = self.lock()?;
let story_exists = connection.query_row(
"SELECT EXISTS(SELECT 1 FROM nodes WHERE story_id = ?1)",
params![story_id],
|row| row.get::<_, bool>(0),
)?;
if !story_exists {
return Err(StoreError::StoryNotFound(story_id.to_owned()));
}
let stored = connection
.query_row(
"SELECT branch_heads.head_node_id, nodes.branch_id, nodes.parent_id,
nodes.node_json, materialized_states.state_json
FROM branch_heads
JOIN nodes
ON nodes.story_id = branch_heads.story_id
AND nodes.node_id = branch_heads.head_node_id
AND nodes.branch_id = branch_heads.branch_id
LEFT JOIN materialized_states
ON materialized_states.story_id = branch_heads.story_id
AND materialized_states.node_id = branch_heads.head_node_id
WHERE branch_heads.story_id = ?1
AND branch_heads.branch_id = ?2",
params![story_id, branch_id],
|row| {
Ok((
row.get::<_, String>(0)?,
row.get::<_, String>(1)?,
row.get::<_, Option<String>>(2)?,
row.get::<_, String>(3)?,
row.get::<_, Option<String>>(4)?,
))
},
)
.optional()?
.ok_or_else(|| StoreError::BranchNotFound {
story_id: story_id.to_owned(),
branch_id: branch_id.to_owned(),
})?;
let node = deserialize_node(&stored.3)?;
validate_loaded_node(
&node,
story_id,
&stored.0,
&stored.1,
stored.2.as_deref(),
)?;
let state_json = stored
.4
.ok_or(StoreError::StateMismatch("branch head has no state"))?;
let state = deserialize_state(&state_json)?;
validate_loaded_state(&state, story_id, &stored.0, branch_id)?;
validate_state_hash(&node, &state)?;
Ok(state)
}
fn load_node(&self, story_id: &str, node_id: &str) -> Result<StoryNode, StoreError> {
let connection = self.lock()?;
let stored = connection
.query_row(
"SELECT branch_id, parent_id, node_json
FROM nodes
WHERE story_id = ?1 AND node_id = ?2",
params![story_id, node_id],
|row| {
Ok((
row.get::<_, String>(0)?,
row.get::<_, Option<String>>(1)?,
row.get::<_, String>(2)?,
))
},
)
.optional()?
.ok_or_else(|| StoreError::ParentNotFound(node_id.to_owned()))?;
let node = deserialize_node(&stored.2)?;
validate_loaded_node(&node, story_id, node_id, &stored.0, stored.1.as_deref())?;
Ok(node)
}
}
fn initialize_schema(connection: &Connection) -> Result<(), StoreError> {
connection.execute_batch(
"PRAGMA foreign_keys = ON;
BEGIN IMMEDIATE;
CREATE TABLE IF NOT EXISTS nodes (
story_id TEXT NOT NULL,
node_id TEXT NOT NULL,
branch_id TEXT NOT NULL,
parent_id TEXT,
node_json TEXT NOT NULL,
PRIMARY KEY (story_id, node_id),
FOREIGN KEY (story_id, parent_id)
REFERENCES nodes (story_id, node_id)
ON DELETE RESTRICT
);
CREATE UNIQUE INDEX IF NOT EXISTS one_root_per_story
ON nodes (story_id)
WHERE parent_id IS NULL;
CREATE TABLE IF NOT EXISTS materialized_states (
story_id TEXT NOT NULL,
node_id TEXT NOT NULL,
state_json TEXT NOT NULL,
PRIMARY KEY (story_id, node_id),
FOREIGN KEY (story_id, node_id)
REFERENCES nodes (story_id, node_id)
ON DELETE RESTRICT
);
CREATE TABLE IF NOT EXISTS branch_heads (
story_id TEXT NOT NULL,
branch_id TEXT NOT NULL,
head_node_id TEXT NOT NULL,
PRIMARY KEY (story_id, branch_id),
FOREIGN KEY (story_id, head_node_id)
REFERENCES nodes (story_id, node_id)
ON DELETE RESTRICT
);
COMMIT;",
)?;
Ok(())
}
fn validate_materialized_state(
node: &StoryNode,
state: &RuntimeState,
) -> Result<(), StoreError> {
if node.story_id != state.story_id {
return Err(StoreError::StateMismatch("story_id"));
}
if node.id != state.current_node {
return Err(StoreError::StateMismatch("current_node"));
}
if node.branch_id != state.current_branch {
return Err(StoreError::StateMismatch("current_branch"));
}
validate_state_hash(node, state)?;
Ok(())
}
fn deserialize_node(node_json: &str) -> Result<StoryNode, StoreError> {
serde_json::from_str(node_json).map_err(StoreError::from)
}
fn deserialize_state(state_json: &str) -> Result<RuntimeState, StoreError> {
serde_json::from_str(state_json).map_err(StoreError::from)
}
fn validate_loaded_node(
node: &StoryNode,
story_id: &str,
node_id: &str,
branch_id: &str,
parent_id: Option<&str>,
) -> Result<(), StoreError> {
if node.story_id != story_id {
return Err(StoreError::StateMismatch("story_id"));
}
if node.id != node_id {
return Err(StoreError::StateMismatch("current_node"));
}
if node.branch_id != branch_id {
return Err(StoreError::StateMismatch("current_branch"));
}
if node.parent_id.as_deref() != parent_id {
return Err(StoreError::StateMismatch("parent_id"));
}
Ok(())
}
fn validate_loaded_state(
state: &RuntimeState,
story_id: &str,
node_id: &str,
branch_id: &str,
) -> Result<(), StoreError> {
if state.story_id != story_id {
return Err(StoreError::StateMismatch("story_id"));
}
if state.current_node != node_id {
return Err(StoreError::StateMismatch("current_node"));
}
if state.current_branch != branch_id {
return Err(StoreError::StateMismatch("current_branch"));
}
Ok(())
}
fn validate_state_hash(node: &StoryNode, state: &RuntimeState) -> Result<(), StoreError> {
let bytes = serde_json::to_vec(state)?;
if stable_json_hash(&bytes) != node.state_hash {
return Err(StoreError::StateHashMismatch {
node_id: node.id.clone(),
});
}
Ok(())
}
#[cfg(test)]
mod tests {
use std::{
collections::BTreeMap,
fs,
path::{Path, PathBuf},
time::{SystemTime, UNIX_EPOCH},
};
use nana_domain::{RuntimeState, StateDelta, StoryNode, stable_json_hash};
use rusqlite::params;
use super::{InMemoryStoryStore, SqliteStoryStore, StoreError, StoryStore};
fn state(node: &str, branch: &str) -> RuntimeState {
RuntimeState {
story_id: "story_demo".to_owned(),
current_node: node.to_owned(),
current_branch: branch.to_owned(),
world_flags: BTreeMap::new(),
relationships: BTreeMap::new(),
relationship_states: Vec::new(),
promises: Vec::new(),
knowledge: Vec::new(),
items: Vec::new(),
clocks: Vec::new(),
checks: Vec::new(),
}
}
fn node(id: &str, parent_id: Option<&str>, branch: &str) -> StoryNode {
let materialized = state(id, branch);
StoryNode {
id: id.to_owned(),
story_id: "story_demo".to_owned(),
branch_id: branch.to_owned(),
parent_id: parent_id.map(ToOwned::to_owned),
action_id: format!("action_{id}"),
user_input: String::new(),
beats: Vec::new(),
delta: StateDelta { ops: Vec::new() },
state_hash: stable_json_hash(
&serde_json::to_vec(&materialized).expect("serializable test state"),
),
}
}
trait InspectableStoryStore: StoryStore {
fn inspected_branch_head(
&self,
story_id: &str,
branch_id: &str,
) -> Result<Option<String>, StoreError>;
fn inspected_state_at_node(
&self,
story_id: &str,
node_id: &str,
) -> Result<RuntimeState, StoreError>;
}
impl InspectableStoryStore for InMemoryStoryStore {
fn inspected_branch_head(
&self,
story_id: &str,
branch_id: &str,
) -> Result<Option<String>, StoreError> {
self.branch_head(story_id, branch_id)
}
fn inspected_state_at_node(
&self,
story_id: &str,
node_id: &str,
) -> Result<RuntimeState, StoreError> {
self.load_state_at_node(story_id, node_id)
}
}
impl InspectableStoryStore for SqliteStoryStore {
fn inspected_branch_head(
&self,
story_id: &str,
branch_id: &str,
) -> Result<Option<String>, StoreError> {
self.branch_head(story_id, branch_id)
}
fn inspected_state_at_node(
&self,
story_id: &str,
node_id: &str,
) -> Result<RuntimeState, StoreError> {
self.load_state_at_node(story_id, node_id)
}
}
fn assert_appends_and_loads_the_branch_head(store: &impl InspectableStoryStore) {
store
.append_node(
&node("node_001", None, "branch_main"),
&state("node_001", "branch_main"),
)
.expect("root append");
store
.append_node(
&node("node_002", Some("node_001"), "branch_main"),
&state("node_002", "branch_main"),
)
.expect("child append");
assert_eq!(
store
.load_state("story_demo", "branch_main")
.expect("stored state")
.current_node,
"node_002"
);
assert_eq!(
store
.inspected_state_at_node("story_demo", "node_001")
.expect("root state")
.current_node,
"node_001"
);
assert_eq!(
store
.load_node("story_demo", "node_002")
.expect("stored node")
.parent_id
.as_deref(),
Some("node_001")
);
}
fn assert_forks_from_an_old_node(store: &impl InspectableStoryStore) {
store
.append_node(
&node("node_001", None, "branch_main"),
&state("node_001", "branch_main"),
)
.expect("root append");
store
.append_node(
&node("node_002", Some("node_001"), "branch_main"),
&state("node_002", "branch_main"),
)
.expect("main append");
store
.append_node(
&node("node_003", Some("node_001"), "branch_rewind"),
&state("node_003", "branch_rewind"),
)
.expect("fork append");
assert_eq!(
store
.inspected_branch_head("story_demo", "branch_main")
.expect("main head"),
Some("node_002".to_owned())
);
assert_eq!(
store
.inspected_branch_head("story_demo", "branch_rewind")
.expect("fork head"),
Some("node_003".to_owned())
);
}
fn assert_rejects_a_stale_append(store: &impl InspectableStoryStore) {
store
.append_node(
&node("node_001", None, "branch_main"),
&state("node_001", "branch_main"),
)
.expect("root append");
store
.append_node(
&node("node_002", Some("node_001"), "branch_main"),
&state("node_002", "branch_main"),
)
.expect("main append");
assert_eq!(
store.append_node(
&node("node_stale", Some("node_001"), "branch_main"),
&state("node_stale", "branch_main"),
),
Err(StoreError::StaleBranchHead {
expected: "node_002".to_owned(),
actual: "node_001".to_owned(),
})
);
assert_eq!(
store
.inspected_branch_head("story_demo", "branch_main")
.expect("main head"),
Some("node_002".to_owned())
);
assert_eq!(
store.inspected_state_at_node("story_demo", "node_stale"),
Err(StoreError::ParentNotFound("node_stale".to_owned()))
);
}
fn assert_rejects_state_mismatches(store: &impl InspectableStoryStore) {
let root = node("node_001", None, "branch_main");
let mut wrong_story = state("node_001", "branch_main");
wrong_story.story_id = "another_story".to_owned();
assert_eq!(
store.append_node(&root, &wrong_story),
Err(StoreError::StateMismatch("story_id"))
);
assert_eq!(
store.append_node(&root, &state("different_node", "branch_main")),
Err(StoreError::StateMismatch("current_node"))
);
assert_eq!(
store.append_node(&root, &state("node_001", "different_branch")),
Err(StoreError::StateMismatch("current_branch"))
);
assert_eq!(
store
.inspected_branch_head("story_demo", "branch_main")
.expect("empty store"),
None
);
}
#[test]
fn memory_appends_and_loads_the_branch_head() {
let store = InMemoryStoryStore::new();
assert_appends_and_loads_the_branch_head(&store);
}
#[test]
fn sqlite_appends_and_loads_the_branch_head() {
let store = SqliteStoryStore::open_in_memory().expect("in-memory SQLite store");
assert_appends_and_loads_the_branch_head(&store);
}
#[test]
fn memory_forks_from_an_old_node_without_moving_the_source_head() {
let store = InMemoryStoryStore::new();
assert_forks_from_an_old_node(&store);
}
#[test]
fn sqlite_forks_from_an_old_node_without_moving_the_source_head() {
let store = SqliteStoryStore::open_in_memory().expect("in-memory SQLite store");
assert_forks_from_an_old_node(&store);
}
#[test]
fn memory_rejects_a_stale_append_without_moving_the_head() {
let store = InMemoryStoryStore::new();
assert_rejects_a_stale_append(&store);
}
#[test]
fn sqlite_rejects_a_stale_append_without_moving_the_head() {
let store = SqliteStoryStore::open_in_memory().expect("in-memory SQLite store");
assert_rejects_a_stale_append(&store);
}
#[test]
fn memory_rejects_state_that_does_not_match_the_node() {
let store = InMemoryStoryStore::new();
assert_rejects_state_mismatches(&store);
}
#[test]
fn sqlite_rejects_state_that_does_not_match_the_node() {
let store = SqliteStoryStore::open_in_memory().expect("in-memory SQLite store");
assert_rejects_state_mismatches(&store);
}
#[test]
fn sqlite_enforces_node_and_parent_rules_atomically() {
let store = SqliteStoryStore::open_in_memory().expect("in-memory SQLite store");
let root = node("node_001", None, "branch_main");
let root_state = state("node_001", "branch_main");
store
.append_node(&root, &root_state)
.expect("root append");
assert_eq!(
store.append_node(&root, &root_state),
Err(StoreError::NodeAlreadyExists("node_001".to_owned()))
);
assert_eq!(
store.append_node(
&node("node_missing_parent", Some("unknown"), "branch_fork"),
&state("node_missing_parent", "branch_fork"),
),
Err(StoreError::ParentNotFound("unknown".to_owned()))
);
assert_eq!(
store.append_node(
&node("node_second_root", None, "branch_other"),
&state("node_second_root", "branch_other"),
),
Err(StoreError::ParentNotFound(
"a non-root node must name its parent".to_owned()
))
);
assert_eq!(
store
.branch_head("story_demo", "branch_main")
.expect("main head"),
Some("node_001".to_owned())
);
assert_eq!(
store
.branch_head("story_demo", "branch_fork")
.expect("failed fork"),
None
);
}
#[test]
fn sqlite_reports_corrupt_json_without_panicking() {
let store = SqliteStoryStore::open_in_memory().expect("in-memory SQLite store");
store
.append_node(
&node("node_001", None, "branch_main"),
&state("node_001", "branch_main"),
)
.expect("root append");
store
.connection
.lock()
.expect("SQLite connection lock")
.execute(
"UPDATE materialized_states SET state_json = ?1",
params!["{"],
)
.expect("corrupt test state");
assert!(matches!(
store.load_state("story_demo", "branch_main"),
Err(StoreError::Serialization(_))
));
}
#[test]
fn sqlite_rejects_valid_state_json_with_a_mismatched_hash() {
let store = SqliteStoryStore::open_in_memory().expect("in-memory SQLite store");
store
.append_node(
&node("node_001", None, "branch_main"),
&state("node_001", "branch_main"),
)
.expect("root append");
let mut corrupted = state("node_001", "branch_main");
corrupted
.world_flags
.insert("silently_changed".to_owned(), true);
let corrupted_json = serde_json::to_string(&corrupted).expect("corrupt test JSON");
store
.connection
.lock()
.expect("SQLite connection lock")
.execute(
"UPDATE materialized_states SET state_json = ?1",
params![corrupted_json],
)
.expect("corrupt test state");
assert_eq!(
store.load_state("story_demo", "branch_main"),
Err(StoreError::StateHashMismatch {
node_id: "node_001".to_owned()
})
);
}
#[test]
fn sqlite_rejects_node_json_that_disagrees_with_structure_columns() {
let store = SqliteStoryStore::open_in_memory().expect("in-memory SQLite store");
store
.append_node(
&node("node_001", None, "branch_main"),
&state("node_001", "branch_main"),
)
.expect("root append");
let mut corrupted = node("node_001", None, "branch_main");
corrupted.branch_id = "hidden_branch".to_owned();
let corrupted_json = serde_json::to_string(&corrupted).expect("corrupt node JSON");
store
.connection
.lock()
.expect("SQLite connection lock")
.execute(
"UPDATE nodes SET node_json = ?1",
params![corrupted_json],
)
.expect("corrupt test node");
assert_eq!(
store.load_node("story_demo", "node_001"),
Err(StoreError::StateMismatch("current_branch"))
);
}
#[test]
fn sqlite_rejects_a_branch_head_pointing_at_another_branch() {
let store = SqliteStoryStore::open_in_memory().expect("in-memory SQLite store");
store
.append_node(
&node("node_001", None, "branch_main"),
&state("node_001", "branch_main"),
)
.expect("root append");
store
.append_node(
&node("node_other", Some("node_001"), "branch_other"),
&state("node_other", "branch_other"),
)
.expect("other branch append");
store
.connection
.lock()
.expect("SQLite connection lock")
.execute(
"UPDATE branch_heads
SET head_node_id = 'node_other'
WHERE story_id = 'story_demo' AND branch_id = 'branch_main'",
[],
)
.expect("corrupt branch head");
assert_eq!(
store.load_state("story_demo", "branch_main"),
Err(StoreError::BranchNotFound {
story_id: "story_demo".to_owned(),
branch_id: "branch_main".to_owned()
})
);
}
struct TemporaryDatabase {
path: PathBuf,
}
impl TemporaryDatabase {
fn new() -> Self {
let nonce = SystemTime::now()
.duration_since(UNIX_EPOCH)
.unwrap_or_default()
.as_nanos();
Self {
path: std::env::temp_dir().join(format!(
"nana-store-{}-{nonce}.sqlite3",
std::process::id()
)),
}
}
fn path(&self) -> &Path {
&self.path
}
}
impl Drop for TemporaryDatabase {
fn drop(&mut self) {
if self.path.exists() {
fs::remove_file(&self.path).expect("remove temporary SQLite database");
}
}
}
#[test]
fn sqlite_reopens_and_preserves_nodes_states_and_heads() {
let database = TemporaryDatabase::new();
{
let store = SqliteStoryStore::open(database.path()).expect("file SQLite store");
store
.append_node(
&node("node_001", None, "branch_main"),
&state("node_001", "branch_main"),
)
.expect("root append");
store
.append_node(
&node("node_002", Some("node_001"), "branch_main"),
&state("node_002", "branch_main"),
)
.expect("child append");
}
let reopened = SqliteStoryStore::open(database.path()).expect("reopened SQLite store");
assert_eq!(
reopened
.branch_head("story_demo", "branch_main")
.expect("persisted head"),
Some("node_002".to_owned())
);
assert_eq!(
reopened
.load_state("story_demo", "branch_main")
.expect("persisted head state")
.current_node,
"node_002"
);
assert_eq!(
reopened
.load_state_at_node("story_demo", "node_001")
.expect("persisted root state")
.current_node,
"node_001"
);
}
}