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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
use crate::error::*;
use rusqlite::{Connection, Transaction};
use serde::{ser::SerializeMap, Serialize, Serializer};
use serde_json::{Map, Value as JsonValue};
use sql_support::{self, ConnExt};
// These constants are defined by the chrome.storage.sync spec. We export them
// publicly from this module, then from the crate, so they wind up in the
// clients.
// Note the limits for `chrome.storage.sync` and `chrome.storage.local` are
// different, and these are from `.sync` - we'll have work to do if we end up
// wanting this to be used for `.local` too!
pub const SYNC_QUOTA_BYTES: usize = 102_400;
pub const SYNC_QUOTA_BYTES_PER_ITEM: usize = 8_192;
pub const SYNC_MAX_ITEMS: usize = 512;
// Note there are also constants for "operations per minute" etc, which aren't
// enforced here.
type JsonMap = Map<String, JsonValue>;
enum StorageChangeOp {
Clear,
Set(JsonValue),
SetWithoutQuota(JsonValue),
}
fn get_from_db(conn: &Connection, ext_id: &str) -> Result<Option<JsonMap>> {
Ok(
match conn.try_query_one::<String, _>(
"SELECT data FROM storage_sync_data
WHERE ext_id = :ext_id",
&[(":ext_id", &ext_id)],
true,
)? {
Some(s) => match serde_json::from_str(&s)? {
JsonValue::Object(m) => Some(m),
// we could panic here as it's theoretically impossible, but we
// might as well treat it as not existing...
_ => None,
},
None => None,
},
)
}
fn save_to_db(tx: &Transaction<'_>, ext_id: &str, val: &StorageChangeOp) -> Result<()> {
// This function also handles removals. Either an empty map or explicit null
// is a removal. If there's a mirror record for this extension ID, then we
// must leave a tombstone behind for syncing.
let is_delete = match val {
StorageChangeOp::Clear => true,
StorageChangeOp::Set(JsonValue::Object(v)) => v.is_empty(),
StorageChangeOp::SetWithoutQuota(JsonValue::Object(v)) => v.is_empty(),
_ => false,
};
if is_delete {
let in_mirror = tx
.try_query_one(
"SELECT EXISTS(SELECT 1 FROM storage_sync_mirror WHERE ext_id = :ext_id);",
rusqlite::named_params! {
":ext_id": ext_id,
},
true,
)?
.unwrap_or_default();
if in_mirror {
log::trace!("saving data for '{}': leaving a tombstone", ext_id);
tx.execute_cached(
"
INSERT INTO storage_sync_data(ext_id, data, sync_change_counter)
VALUES (:ext_id, NULL, 1)
ON CONFLICT (ext_id) DO UPDATE
SET data = NULL, sync_change_counter = sync_change_counter + 1",
rusqlite::named_params! {
":ext_id": ext_id,
},
)?;
} else {
log::trace!("saving data for '{}': removing the row", ext_id);
tx.execute_cached(
"
DELETE FROM storage_sync_data WHERE ext_id = :ext_id",
rusqlite::named_params! {
":ext_id": ext_id,
},
)?;
}
} else {
// Convert to bytes so we can enforce the quota if necessary.
let sval = match val {
StorageChangeOp::Set(v) => {
let sv = v.to_string();
if sv.len() > SYNC_QUOTA_BYTES {
return Err(Error::QuotaError(QuotaReason::TotalBytes));
}
sv
}
StorageChangeOp::SetWithoutQuota(v) => v.to_string(),
StorageChangeOp::Clear => unreachable!(),
};
log::trace!("saving data for '{}': writing", ext_id);
tx.execute_cached(
"INSERT INTO storage_sync_data(ext_id, data, sync_change_counter)
VALUES (:ext_id, :data, 1)
ON CONFLICT (ext_id) DO UPDATE
set data=:data, sync_change_counter = sync_change_counter + 1",
rusqlite::named_params! {
":ext_id": ext_id,
":data": &sval,
},
)?;
}
Ok(())
}
fn remove_from_db(tx: &Transaction<'_>, ext_id: &str) -> Result<()> {
save_to_db(tx, ext_id, &StorageChangeOp::Clear)
}
// This is a "helper struct" for the callback part of the chrome.storage spec,
// but shaped in a way to make it more convenient from the rust side of the
// world.
#[derive(Debug, Clone, PartialEq, Eq, Serialize)]
#[serde(rename_all = "camelCase")]
pub struct StorageValueChange {
#[serde(skip_serializing)]
pub key: String,
#[serde(skip_serializing_if = "Option::is_none")]
pub old_value: Option<JsonValue>,
#[serde(skip_serializing_if = "Option::is_none")]
pub new_value: Option<JsonValue>,
}
// This is, largely, a helper so that this serializes correctly as per the
// chrome.storage.sync spec. If not for custom serialization it should just
// be a plain vec
#[derive(Debug, Default, Clone, PartialEq, Eq)]
pub struct StorageChanges {
pub changes: Vec<StorageValueChange>,
}
impl StorageChanges {
pub fn new() -> Self {
Self::default()
}
pub fn with_capacity(n: usize) -> Self {
Self {
changes: Vec::with_capacity(n),
}
}
pub fn is_empty(&self) -> bool {
self.changes.is_empty()
}
pub fn push(&mut self, change: StorageValueChange) {
self.changes.push(change)
}
}
// and it serializes as a map.
impl Serialize for StorageChanges {
fn serialize<S>(&self, serializer: S) -> std::result::Result<S::Ok, S::Error>
where
S: Serializer,
{
let mut map = serializer.serialize_map(Some(self.changes.len()))?;
for change in &self.changes {
map.serialize_entry(&change.key, change)?;
}
map.end()
}
}
// A helper to determine the size of a key/value combination from the
// perspective of quota and getBytesInUse().
pub fn get_quota_size_of(key: &str, v: &JsonValue) -> usize {
// Reading the chrome docs literally re the quota, the length of the key
// is just the string len, but the value is the json val, as bytes.
key.len() + v.to_string().len()
}
/// The implementation of `storage[.sync].set()`. On success this returns the
/// StorageChanges defined by the chrome API - it's assumed the caller will
/// arrange to deliver this to observers as defined in that API.
pub fn set(tx: &Transaction<'_>, ext_id: &str, val: JsonValue) -> Result<StorageChanges> {
let val_map = match val {
JsonValue::Object(m) => m,
// Not clear what the error semantics should be yet. For now, pretend an empty map.
_ => Map::new(),
};
let mut current = get_from_db(tx, ext_id)?.unwrap_or_default();
let mut changes = StorageChanges::with_capacity(val_map.len());
// iterate over the value we are adding/updating.
for (k, v) in val_map.into_iter() {
let old_value = current.remove(&k);
if current.len() >= SYNC_MAX_ITEMS {
return Err(Error::QuotaError(QuotaReason::MaxItems));
}
// Reading the chrome docs literally re the quota, the length of the key
// is just the string len, but the value is the json val, as bytes
if get_quota_size_of(&k, &v) > SYNC_QUOTA_BYTES_PER_ITEM {
return Err(Error::QuotaError(QuotaReason::ItemBytes));
}
let change = StorageValueChange {
key: k.clone(),
old_value,
new_value: Some(v.clone()),
};
changes.push(change);
current.insert(k, v);
}
save_to_db(
tx,
ext_id,
&StorageChangeOp::Set(JsonValue::Object(current)),
)?;
Ok(changes)
}
// A helper which takes a param indicating what keys should be returned and
// converts that to a vec of real strings. Also returns "default" values to
// be used if no item exists for that key.
fn get_keys(keys: JsonValue) -> Vec<(String, Option<JsonValue>)> {
match keys {
JsonValue::String(s) => vec![(s, None)],
JsonValue::Array(keys) => {
// because nothing with json is ever simple, each key may not be
// a string. We ignore any which aren't.
keys.iter()
.filter_map(|v| v.as_str().map(|s| (s.to_string(), None)))
.collect()
}
JsonValue::Object(m) => m.into_iter().map(|(k, d)| (k, Some(d))).collect(),
_ => vec![],
}
}
/// The implementation of `storage[.sync].get()` - on success this always
/// returns a Json object.
pub fn get(conn: &Connection, ext_id: &str, keys: JsonValue) -> Result<JsonValue> {
// key is optional, or string or array of string or object keys
let maybe_existing = get_from_db(conn, ext_id)?;
let mut existing = match (maybe_existing, keys.is_object()) {
(None, true) => return Ok(keys),
(None, false) => return Ok(JsonValue::Object(Map::new())),
(Some(v), _) => v,
};
// take the quick path for null, where we just return the entire object.
if keys.is_null() {
return Ok(JsonValue::Object(existing));
}
// OK, so we need to build a list of keys to get.
let keys_and_defaults = get_keys(keys);
let mut result = Map::with_capacity(keys_and_defaults.len());
for (key, maybe_default) in keys_and_defaults {
if let Some(v) = existing.remove(&key) {
result.insert(key, v);
} else if let Some(def) = maybe_default {
result.insert(key, def);
}
// else |keys| is a string/array instead of an object with defaults.
// Don't include keys without default values.
}
Ok(JsonValue::Object(result))
}
/// The implementation of `storage[.sync].remove()`. On success this returns the
/// StorageChanges defined by the chrome API - it's assumed the caller will
/// arrange to deliver this to observers as defined in that API.
pub fn remove(tx: &Transaction<'_>, ext_id: &str, keys: JsonValue) -> Result<StorageChanges> {
let mut existing = match get_from_db(tx, ext_id)? {
None => return Ok(StorageChanges::new()),
Some(v) => v,
};
// Note: get_keys parses strings, arrays and objects, but remove()
// is expected to only be passed a string or array of strings.
let keys_and_defs = get_keys(keys);
let mut result = StorageChanges::with_capacity(keys_and_defs.len());
for (key, _) in keys_and_defs {
if let Some(v) = existing.remove(&key) {
result.push(StorageValueChange {
key,
old_value: Some(v),
new_value: None,
});
}
}
if !result.is_empty() {
save_to_db(
tx,
ext_id,
&StorageChangeOp::SetWithoutQuota(JsonValue::Object(existing)),
)?;
}
Ok(result)
}
/// The implementation of `storage[.sync].clear()`. On success this returns the
/// StorageChanges defined by the chrome API - it's assumed the caller will
/// arrange to deliver this to observers as defined in that API.
pub fn clear(tx: &Transaction<'_>, ext_id: &str) -> Result<StorageChanges> {
let existing = match get_from_db(tx, ext_id)? {
None => return Ok(StorageChanges::new()),
Some(v) => v,
};
let mut result = StorageChanges::with_capacity(existing.len());
for (key, val) in existing.into_iter() {
result.push(StorageValueChange {
key: key.to_string(),
new_value: None,
old_value: Some(val),
});
}
remove_from_db(tx, ext_id)?;
Ok(result)
}
/// The implementation of `storage[.sync].getBytesInUse()`.
pub fn get_bytes_in_use(conn: &Connection, ext_id: &str, keys: JsonValue) -> Result<usize> {
let maybe_existing = get_from_db(conn, ext_id)?;
let existing = match maybe_existing {
None => return Ok(0),
Some(v) => v,
};
// Make an array of all the keys we we are going to count.
let keys: Vec<&str> = match &keys {
JsonValue::Null => existing.keys().map(|v| v.as_str()).collect(),
JsonValue::String(name) => vec![name.as_str()],
JsonValue::Array(names) => names.iter().filter_map(|v| v.as_str()).collect(),
// in the spirit of json-based APIs, silently ignore strange things.
_ => return Ok(0),
};
// We must use the same way of counting as our quota enforcement.
let mut size = 0;
for key in keys.into_iter() {
if let Some(v) = existing.get(key) {
size += get_quota_size_of(key, v);
}
}
Ok(size)
}
/// Information about the usage of a single extension.
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct UsageInfo {
/// The extension id.
pub ext_id: String,
/// The number of keys the extension uses.
pub num_keys: usize,
/// The number of bytes used by the extension. This result is somewhat rough
/// -- it doesn't bother counting the size of the extension ID, or data in
/// the mirror, and favors returning the exact number of bytes used by the
/// column (that is, the size of the JSON object) rather than replicating
/// the `get_bytes_in_use` return value for all keys.
pub num_bytes: usize,
}
/// Exposes information about per-collection usage for the purpose of telemetry.
/// (Doesn't map to an actual `chrome.storage.sync` API).
pub fn usage(db: &Connection) -> Result<Vec<UsageInfo>> {
type JsonObject = Map<String, JsonValue>;
let sql = "
SELECT ext_id, data
FROM storage_sync_data
WHERE data IS NOT NULL
-- for tests and determinism
ORDER BY ext_id
";
db.query_rows_into(sql, [], |row| {
let ext_id: String = row.get("ext_id")?;
let data: String = row.get("data")?;
let num_bytes = data.len();
let num_keys = serde_json::from_str::<JsonObject>(&data)?.len();
Ok(UsageInfo {
ext_id,
num_keys,
num_bytes,
})
})
}
#[cfg(test)]
mod tests {
use super::*;
use crate::db::test::new_mem_db;
use serde_json::json;
#[test]
fn test_serialize_storage_changes() -> Result<()> {
let c = StorageChanges {
changes: vec![StorageValueChange {
key: "key".to_string(),
old_value: Some(json!("old")),
new_value: None,
}],
};
assert_eq!(serde_json::to_string(&c)?, r#"{"key":{"oldValue":"old"}}"#);
let c = StorageChanges {
changes: vec![StorageValueChange {
key: "key".to_string(),
old_value: None,
new_value: Some(json!({"foo": "bar"})),
}],
};
assert_eq!(
serde_json::to_string(&c)?,
r#"{"key":{"newValue":{"foo":"bar"}}}"#
);
Ok(())
}
fn make_changes(changes: &[(&str, Option<JsonValue>, Option<JsonValue>)]) -> StorageChanges {
let mut r = StorageChanges::with_capacity(changes.len());
for (name, old_value, new_value) in changes {
r.push(StorageValueChange {
key: (*name).to_string(),
old_value: old_value.clone(),
new_value: new_value.clone(),
});
}
r
}
#[test]
fn test_simple() -> Result<()> {
let ext_id = "x";
let mut db = new_mem_db();
let tx = db.transaction()?;
// an empty store.
for q in vec![JsonValue::Null, json!("foo"), json!(["foo"])].into_iter() {
assert_eq!(get(&tx, ext_id, q)?, json!({}));
}
// Default values in an empty store.
for q in vec![json!({ "foo": null }), json!({"foo": "default"})].into_iter() {
assert_eq!(get(&tx, ext_id, q.clone())?, q.clone());
}
// Single item in the store.
set(&tx, ext_id, json!({"foo": "bar" }))?;
for q in vec![
JsonValue::Null,
json!("foo"),
json!(["foo"]),
json!({ "foo": null }),
json!({"foo": "default"}),
]
.into_iter()
{
assert_eq!(get(&tx, ext_id, q)?, json!({"foo": "bar" }));
}
// Default values in a non-empty store.
for q in vec![
json!({ "non_existing_key": null }),
json!({"non_existing_key": 0}),
json!({"non_existing_key": false}),
json!({"non_existing_key": "default"}),
json!({"non_existing_key": ["array"]}),
json!({"non_existing_key": {"objectkey": "value"}}),
]
.into_iter()
{
assert_eq!(get(&tx, ext_id, q.clone())?, q.clone());
}
// more complex stuff, including changes checking.
assert_eq!(
set(&tx, ext_id, json!({"foo": "new", "other": "also new" }))?,
make_changes(&[
("foo", Some(json!("bar")), Some(json!("new"))),
("other", None, Some(json!("also new")))
])
);
assert_eq!(
get(&tx, ext_id, JsonValue::Null)?,
json!({"foo": "new", "other": "also new"})
);
assert_eq!(get(&tx, ext_id, json!("foo"))?, json!({"foo": "new"}));
assert_eq!(
get(&tx, ext_id, json!(["foo", "other"]))?,
json!({"foo": "new", "other": "also new"})
);
assert_eq!(
get(&tx, ext_id, json!({"foo": null, "default": "yo"}))?,
json!({"foo": "new", "default": "yo"})
);
assert_eq!(
remove(&tx, ext_id, json!("foo"))?,
make_changes(&[("foo", Some(json!("new")), None)]),
);
assert_eq!(
set(&tx, ext_id, json!({"foo": {"sub-object": "sub-value"}}))?,
make_changes(&[("foo", None, Some(json!({"sub-object": "sub-value"}))),])
);
// XXX - other variants.
assert_eq!(
clear(&tx, ext_id)?,
make_changes(&[
("foo", Some(json!({"sub-object": "sub-value"})), None),
("other", Some(json!("also new")), None),
]),
);
assert_eq!(get(&tx, ext_id, JsonValue::Null)?, json!({}));
Ok(())
}
#[test]
fn test_check_get_impl() -> Result<()> {
// This is a port of checkGetImpl in test_ext_storage.js in Desktop.
let ext_id = "x";
let mut db = new_mem_db();
let tx = db.transaction()?;
let prop = "test-prop";
let value = "test-value";
set(&tx, ext_id, json!({ prop: value }))?;
// this is the checkGetImpl part!
let mut data = get(&tx, ext_id, json!(null))?;
assert_eq!(value, json!(data[prop]), "null getter worked for {}", prop);
data = get(&tx, ext_id, json!(prop))?;
assert_eq!(
value,
json!(data[prop]),
"string getter worked for {}",
prop
);
assert_eq!(
data.as_object().unwrap().len(),
1,
"string getter should return an object with a single property"
);
data = get(&tx, ext_id, json!([prop]))?;
assert_eq!(value, json!(data[prop]), "array getter worked for {}", prop);
assert_eq!(
data.as_object().unwrap().len(),
1,
"array getter with a single key should return an object with a single property"
);
// checkGetImpl() uses `{ [prop]: undefined }` - but json!() can't do that :(
// Hopefully it's just testing a simple object, so we use `{ prop: null }`
data = get(&tx, ext_id, json!({ prop: null }))?;
assert_eq!(
value,
json!(data[prop]),
"object getter worked for {}",
prop
);
assert_eq!(
data.as_object().unwrap().len(),
1,
"object getter with a single key should return an object with a single property"
);
Ok(())
}
#[test]
fn test_bug_1621162() -> Result<()> {
// apparently Firefox, unlike Chrome, will not optimize the changes.
let mut db = new_mem_db();
let tx = db.transaction()?;
let ext_id = "xyz";
set(&tx, ext_id, json!({"foo": "bar" }))?;
assert_eq!(
set(&tx, ext_id, json!({"foo": "bar" }))?,
make_changes(&[("foo", Some(json!("bar")), Some(json!("bar")))]),
);
Ok(())
}
#[test]
fn test_quota_maxitems() -> Result<()> {
let mut db = new_mem_db();
let tx = db.transaction()?;
let ext_id = "xyz";
for i in 1..SYNC_MAX_ITEMS + 1 {
set(
&tx,
ext_id,
json!({ format!("key-{}", i): format!("value-{}", i) }),
)?;
}
let e = set(&tx, ext_id, json!({"another": "another"})).unwrap_err();
match e {
Error::QuotaError(QuotaReason::MaxItems) => {}
_ => panic!("unexpected error type"),
};
Ok(())
}
#[test]
fn test_quota_bytesperitem() -> Result<()> {
let mut db = new_mem_db();
let tx = db.transaction()?;
let ext_id = "xyz";
// A string 5 bytes less than the max. This should be counted as being
// 3 bytes less than the max as the quotes are counted. Plus the length
// of the key (no quotes) means we should come in 2 bytes under.
let val = "x".repeat(SYNC_QUOTA_BYTES_PER_ITEM - 5);
// Key length doesn't push it over.
set(&tx, ext_id, json!({ "x": val }))?;
assert_eq!(
get_bytes_in_use(&tx, ext_id, json!("x"))?,
SYNC_QUOTA_BYTES_PER_ITEM - 2
);
// Key length does push it over.
let e = set(&tx, ext_id, json!({ "xxxx": val })).unwrap_err();
match e {
Error::QuotaError(QuotaReason::ItemBytes) => {}
_ => panic!("unexpected error type"),
};
Ok(())
}
#[test]
fn test_quota_bytes() -> Result<()> {
let mut db = new_mem_db();
let tx = db.transaction()?;
let ext_id = "xyz";
let val = "x".repeat(SYNC_QUOTA_BYTES + 1);
// Init an over quota db with a single key.
save_to_db(
&tx,
ext_id,
&StorageChangeOp::SetWithoutQuota(json!({ "x": val })),
)?;
// Adding more data fails.
let e = set(&tx, ext_id, json!({ "y": "newvalue" })).unwrap_err();
match e {
Error::QuotaError(QuotaReason::TotalBytes) => {}
_ => panic!("unexpected error type"),
};
// Remove data does not fails.
remove(&tx, ext_id, json!["x"])?;
// Restore the over quota data.
save_to_db(
&tx,
ext_id,
&StorageChangeOp::SetWithoutQuota(json!({ "y": val })),
)?;
// Overwrite with less data does not fail.
set(&tx, ext_id, json!({ "y": "lessdata" }))?;
Ok(())
}
#[test]
fn test_get_bytes_in_use() -> Result<()> {
let mut db = new_mem_db();
let tx = db.transaction()?;
let ext_id = "xyz";
assert_eq!(get_bytes_in_use(&tx, ext_id, json!(null))?, 0);
set(&tx, ext_id, json!({ "a": "a" }))?; // should be 4
set(&tx, ext_id, json!({ "b": "bb" }))?; // should be 5
set(&tx, ext_id, json!({ "c": "ccc" }))?; // should be 6
set(&tx, ext_id, json!({ "n": 999_999 }))?; // should be 7
assert_eq!(get_bytes_in_use(&tx, ext_id, json!("x"))?, 0);
assert_eq!(get_bytes_in_use(&tx, ext_id, json!("a"))?, 4);
assert_eq!(get_bytes_in_use(&tx, ext_id, json!("b"))?, 5);
assert_eq!(get_bytes_in_use(&tx, ext_id, json!("c"))?, 6);
assert_eq!(get_bytes_in_use(&tx, ext_id, json!("n"))?, 7);
assert_eq!(get_bytes_in_use(&tx, ext_id, json!(["a"]))?, 4);
assert_eq!(get_bytes_in_use(&tx, ext_id, json!(["a", "x"]))?, 4);
assert_eq!(get_bytes_in_use(&tx, ext_id, json!(["a", "b"]))?, 9);
assert_eq!(get_bytes_in_use(&tx, ext_id, json!(["a", "c"]))?, 10);
assert_eq!(
get_bytes_in_use(&tx, ext_id, json!(["a", "b", "c", "n"]))?,
22
);
assert_eq!(get_bytes_in_use(&tx, ext_id, json!(null))?, 22);
Ok(())
}
#[test]
fn test_usage() {
let mut db = new_mem_db();
let tx = db.transaction().unwrap();
// '{"a":"a","b":"bb","c":"ccc","n":999999}': 39 bytes
set(&tx, "xyz", json!({ "a": "a" })).unwrap();
set(&tx, "xyz", json!({ "b": "bb" })).unwrap();
set(&tx, "xyz", json!({ "c": "ccc" })).unwrap();
set(&tx, "xyz", json!({ "n": 999_999 })).unwrap();
// '{"a":"a"}': 9 bytes
set(&tx, "abc", json!({ "a": "a" })).unwrap();
tx.commit().unwrap();
let usage = usage(&db).unwrap();
let expect = [
UsageInfo {
ext_id: "abc".to_string(),
num_keys: 1,
num_bytes: 9,
},
UsageInfo {
ext_id: "xyz".to_string(),
num_keys: 4,
num_bytes: 39,
},
];
assert_eq!(&usage, &expect);
}
}