mentat/db/src/debug.rs
Nick Alexander 32ed56685e (tx) Replace :db/tx with (transaction-tx) transaction function and broaden support. (#664)
:db/tx (and Datomic's version, :datomic/tx) suffer from the same
ambiguities that [a v] lookup references do -- determining the type of
the result is context sensitive.  (In this case, is :db/tx a reference
to the current transaction ID, or is it a valid keyword?)  This commit
addresses the ambiguity by introducing a notion of a transaction
functions, and provides a little scaffolding for adding more (should
the need arise).  I left the scaffolding in place rather than handling
just (transaction-tx) because I started trying to
implement (transaction-instant) as well, which is more difficult --
see the comments.

It's worth noting that this approach generalizes more or less directly
to ?input variables, since those can be eagerly bound like the
implemented transaction function (transaction-tx).
2018-04-26 19:32:14 -07:00

253 lines
8.9 KiB
Rust

// Copyright 2016 Mozilla
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not use
// this file except in compliance with the License. You may obtain a copy of the
// License at http://www.apache.org/licenses/LICENSE-2.0
// Unless required by applicable law or agreed to in writing, software distributed
// under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
// CONDITIONS OF ANY KIND, either express or implied. See the License for the
// specific language governing permissions and limitations under the License.
#![allow(dead_code)]
/// Low-level functions for testing.
use std::borrow::Borrow;
use std::io::{Write};
use itertools::Itertools;
use rusqlite;
use rusqlite::types::{ToSql};
use tabwriter::TabWriter;
use bootstrap;
use db::TypedSQLValue;
use edn;
use entids;
use errors::Result;
use mentat_core::{
HasSchema,
SQLValueType,
TypedValue,
ValueType,
};
use mentat_tx::entities::{Entid};
use schema::{
SchemaBuilding,
};
use types::Schema;
/// Represents a *datom* (assertion) in the store.
#[derive(Clone,Debug,Eq,Hash,Ord,PartialOrd,PartialEq)]
pub(crate) struct Datom {
// TODO: generalize this.
e: Entid,
a: Entid,
v: edn::Value,
tx: i64,
added: Option<bool>,
}
/// Represents a set of datoms (assertions) in the store.
///
/// To make comparision easier, we deterministically order. The ordering is the ascending tuple
/// ordering determined by `(e, a, (value_type_tag, v), tx)`, where `value_type_tag` is an internal
/// value that is not exposed but is deterministic.
pub(crate) struct Datoms(pub Vec<Datom>);
/// Represents an ordered sequence of transactions in the store.
///
/// To make comparision easier, we deterministically order. The ordering is the ascending tuple
/// ordering determined by `(e, a, (value_type_tag, v), tx, added)`, where `value_type_tag` is an
/// internal value that is not exposed but is deterministic, and `added` is ordered such that
/// retracted assertions appear before added assertions.
pub(crate) struct Transactions(pub Vec<Datoms>);
/// Represents the fulltext values in the store.
pub(crate) struct FulltextValues(pub Vec<(i64, String)>);
impl Datom {
pub(crate) fn into_edn(&self) -> edn::Value {
let f = |entid: &Entid| -> edn::Value {
match *entid {
Entid::Entid(ref y) => edn::Value::Integer(y.clone()),
Entid::Ident(ref y) => edn::Value::NamespacedKeyword(y.clone()),
}
};
let mut v = vec![f(&self.e), f(&self.a), self.v.clone()];
if let Some(added) = self.added {
v.push(edn::Value::Integer(self.tx));
v.push(edn::Value::Boolean(added));
}
edn::Value::Vector(v)
}
}
impl Datoms {
pub(crate) fn into_edn(&self) -> edn::Value {
edn::Value::Vector((&self.0).into_iter().map(|x| x.into_edn()).collect())
}
}
impl Transactions {
pub(crate) fn into_edn(&self) -> edn::Value {
edn::Value::Vector((&self.0).into_iter().map(|x| x.into_edn()).collect())
}
}
impl FulltextValues {
pub(crate) fn into_edn(&self) -> edn::Value {
edn::Value::Vector((&self.0).into_iter().map(|&(x, ref y)| edn::Value::Vector(vec![edn::Value::Integer(x), edn::Value::Text(y.clone())])).collect())
}
}
/// Turn TypedValue::Ref into TypedValue::Keyword when it is possible.
trait ToIdent {
fn map_ident(self, schema: &Schema) -> Self;
}
impl ToIdent for TypedValue {
fn map_ident(self, schema: &Schema) -> Self {
if let TypedValue::Ref(e) = self {
schema.get_ident(e).cloned().map(|i| i.into()).unwrap_or(TypedValue::Ref(e))
} else {
self
}
}
}
/// Convert a numeric entid to an ident `Entid` if possible, otherwise a numeric `Entid`.
fn to_entid(schema: &Schema, entid: i64) -> Entid {
schema.get_ident(entid).map_or(Entid::Entid(entid), |ident| Entid::Ident(ident.clone()))
}
/// Return the set of datoms in the store, ordered by (e, a, v, tx), but not including any datoms of
/// the form [... :db/txInstant ...].
pub(crate) fn datoms<S: Borrow<Schema>>(conn: &rusqlite::Connection, schema: &S) -> Result<Datoms> {
datoms_after(conn, schema, bootstrap::TX0 - 1)
}
/// Return the set of datoms in the store with transaction ID strictly greater than the given `tx`,
/// ordered by (e, a, v, tx).
///
/// The datom set returned does not include any datoms of the form [... :db/txInstant ...].
pub(crate) fn datoms_after<S: Borrow<Schema>>(conn: &rusqlite::Connection, schema: &S, tx: i64) -> Result<Datoms> {
let borrowed_schema = schema.borrow();
let mut stmt: rusqlite::Statement = conn.prepare("SELECT e, a, v, value_type_tag, tx FROM datoms WHERE tx > ? ORDER BY e ASC, a ASC, value_type_tag ASC, v ASC, tx ASC")?;
let r: Result<Vec<_>> = stmt.query_and_then(&[&tx], |row| {
let e: i64 = row.get_checked(0)?;
let a: i64 = row.get_checked(1)?;
if a == entids::DB_TX_INSTANT {
return Ok(None);
}
let v: rusqlite::types::Value = row.get_checked(2)?;
let value_type_tag: i32 = row.get_checked(3)?;
let attribute = borrowed_schema.require_attribute_for_entid(a)?;
let value_type_tag = if !attribute.fulltext { value_type_tag } else { ValueType::Long.value_type_tag() };
let typed_value = TypedValue::from_sql_value_pair(v, value_type_tag)?.map_ident(borrowed_schema);
let (value, _) = typed_value.to_edn_value_pair();
let tx: i64 = row.get_checked(4)?;
Ok(Some(Datom {
e: Entid::Entid(e),
a: to_entid(borrowed_schema, a),
v: value,
tx: tx,
added: None,
}))
})?.collect();
Ok(Datoms(r?.into_iter().filter_map(|x| x).collect()))
}
/// Return the sequence of transactions in the store with transaction ID strictly greater than the
/// given `tx`, ordered by (tx, e, a, v).
///
/// Each transaction returned includes the [(transaction-tx) :db/txInstant ...] datom.
pub(crate) fn transactions_after<S: Borrow<Schema>>(conn: &rusqlite::Connection, schema: &S, tx: i64) -> Result<Transactions> {
let borrowed_schema = schema.borrow();
let mut stmt: rusqlite::Statement = conn.prepare("SELECT e, a, v, value_type_tag, tx, added FROM transactions WHERE tx > ? ORDER BY tx ASC, e ASC, a ASC, value_type_tag ASC, v ASC, added ASC")?;
let r: Result<Vec<_>> = stmt.query_and_then(&[&tx], |row| {
let e: i64 = row.get_checked(0)?;
let a: i64 = row.get_checked(1)?;
let v: rusqlite::types::Value = row.get_checked(2)?;
let value_type_tag: i32 = row.get_checked(3)?;
let attribute = borrowed_schema.require_attribute_for_entid(a)?;
let value_type_tag = if !attribute.fulltext { value_type_tag } else { ValueType::Long.value_type_tag() };
let typed_value = TypedValue::from_sql_value_pair(v, value_type_tag)?.map_ident(borrowed_schema);
let (value, _) = typed_value.to_edn_value_pair();
let tx: i64 = row.get_checked(4)?;
let added: bool = row.get_checked(5)?;
Ok(Datom {
e: Entid::Entid(e),
a: to_entid(borrowed_schema, a),
v: value,
tx: tx,
added: Some(added),
})
})?.collect();
// Group by tx.
let r: Vec<Datoms> = r?.into_iter().group_by(|x| x.tx).into_iter().map(|(_key, group)| Datoms(group.collect())).collect();
Ok(Transactions(r))
}
/// Return the set of fulltext values in the store, ordered by rowid.
pub(crate) fn fulltext_values(conn: &rusqlite::Connection) -> Result<FulltextValues> {
let mut stmt: rusqlite::Statement = conn.prepare("SELECT rowid, text FROM fulltext_values ORDER BY rowid")?;
let r: Result<Vec<_>> = stmt.query_and_then(&[], |row| {
let rowid: i64 = row.get_checked(0)?;
let text: String = row.get_checked(1)?;
Ok((rowid, text))
})?.collect();
r.map(FulltextValues)
}
/// Execute the given `sql` query with the given `params` and format the results as a
/// tab-and-newline formatted string suitable for debug printing.
///
/// The query is printed followed by a newline, then the returned columns followed by a newline, and
/// then the data rows and columns. All columns are aligned.
pub(crate) fn dump_sql_query(conn: &rusqlite::Connection, sql: &str, params: &[&ToSql]) -> Result<String> {
let mut stmt: rusqlite::Statement = conn.prepare(sql)?;
let mut tw = TabWriter::new(Vec::new()).padding(2);
write!(&mut tw, "{}\n", sql).unwrap();
for column_name in stmt.column_names() {
write!(&mut tw, "{}\t", column_name).unwrap();
}
write!(&mut tw, "\n").unwrap();
let r: Result<Vec<_>> = stmt.query_and_then(params, |row| {
for i in 0..row.column_count() {
let value: rusqlite::types::Value = row.get_checked(i)?;
write!(&mut tw, "{:?}\t", value).unwrap();
}
write!(&mut tw, "\n").unwrap();
Ok(())
})?.collect();
r?;
let dump = String::from_utf8(tw.into_inner().unwrap()).unwrap();
Ok(dump)
}