the-forest/client/node_modules/@libsql/hrana-client/lib-esm/batch.js
2024-09-17 20:35:18 -04:00

272 lines
9.8 KiB
JavaScript

import { ProtoError, MisuseError } from "./errors.js";
import { stmtResultFromProto, rowsResultFromProto, rowResultFromProto, valueResultFromProto, errorFromProto, } from "./result.js";
import { stmtToProto } from "./stmt.js";
import { impossible } from "./util.js";
/** A builder for creating a batch and executing it on the server. */
export class Batch {
/** @private */
_stream;
#useCursor;
/** @private */
_steps;
#executed;
/** @private */
constructor(stream, useCursor) {
this._stream = stream;
this.#useCursor = useCursor;
this._steps = [];
this.#executed = false;
}
/** Return a builder for adding a step to the batch. */
step() {
return new BatchStep(this);
}
/** Execute the batch. */
execute() {
if (this.#executed) {
throw new MisuseError("This batch has already been executed");
}
this.#executed = true;
const batch = {
steps: this._steps.map((step) => step.proto),
};
if (this.#useCursor) {
return executeCursor(this._stream, this._steps, batch);
}
else {
return executeRegular(this._stream, this._steps, batch);
}
}
}
function executeRegular(stream, steps, batch) {
return stream._batch(batch).then((result) => {
for (let step = 0; step < steps.length; ++step) {
const stepResult = result.stepResults.get(step);
const stepError = result.stepErrors.get(step);
steps[step].callback(stepResult, stepError);
}
});
}
async function executeCursor(stream, steps, batch) {
const cursor = await stream._openCursor(batch);
try {
let nextStep = 0;
let beginEntry = undefined;
let rows = [];
for (;;) {
const entry = await cursor.next();
if (entry === undefined) {
break;
}
if (entry.type === "step_begin") {
if (entry.step < nextStep || entry.step >= steps.length) {
throw new ProtoError("Server produced StepBeginEntry for unexpected step");
}
else if (beginEntry !== undefined) {
throw new ProtoError("Server produced StepBeginEntry before terminating previous step");
}
for (let step = nextStep; step < entry.step; ++step) {
steps[step].callback(undefined, undefined);
}
nextStep = entry.step + 1;
beginEntry = entry;
rows = [];
}
else if (entry.type === "step_end") {
if (beginEntry === undefined) {
throw new ProtoError("Server produced StepEndEntry but no step is active");
}
const stmtResult = {
cols: beginEntry.cols,
rows,
affectedRowCount: entry.affectedRowCount,
lastInsertRowid: entry.lastInsertRowid,
};
steps[beginEntry.step].callback(stmtResult, undefined);
beginEntry = undefined;
rows = [];
}
else if (entry.type === "step_error") {
if (beginEntry === undefined) {
if (entry.step >= steps.length) {
throw new ProtoError("Server produced StepErrorEntry for unexpected step");
}
for (let step = nextStep; step < entry.step; ++step) {
steps[step].callback(undefined, undefined);
}
}
else {
if (entry.step !== beginEntry.step) {
throw new ProtoError("Server produced StepErrorEntry for unexpected step");
}
beginEntry = undefined;
rows = [];
}
steps[entry.step].callback(undefined, entry.error);
nextStep = entry.step + 1;
}
else if (entry.type === "row") {
if (beginEntry === undefined) {
throw new ProtoError("Server produced RowEntry but no step is active");
}
rows.push(entry.row);
}
else if (entry.type === "error") {
throw errorFromProto(entry.error);
}
else if (entry.type === "none") {
throw new ProtoError("Server produced unrecognized CursorEntry");
}
else {
throw impossible(entry, "Impossible CursorEntry");
}
}
if (beginEntry !== undefined) {
throw new ProtoError("Server closed Cursor before terminating active step");
}
for (let step = nextStep; step < steps.length; ++step) {
steps[step].callback(undefined, undefined);
}
}
finally {
cursor.close();
}
}
/** A builder for adding a step to the batch. */
export class BatchStep {
/** @private */
_batch;
#conds;
/** @private */
_index;
/** @private */
constructor(batch) {
this._batch = batch;
this.#conds = [];
this._index = undefined;
}
/** Add the condition that needs to be satisfied to execute the statement. If you use this method multiple
* times, we join the conditions with a logical AND. */
condition(cond) {
this.#conds.push(cond._proto);
return this;
}
/** Add a statement that returns rows. */
query(stmt) {
return this.#add(stmt, true, rowsResultFromProto);
}
/** Add a statement that returns at most a single row. */
queryRow(stmt) {
return this.#add(stmt, true, rowResultFromProto);
}
/** Add a statement that returns at most a single value. */
queryValue(stmt) {
return this.#add(stmt, true, valueResultFromProto);
}
/** Add a statement without returning rows. */
run(stmt) {
return this.#add(stmt, false, stmtResultFromProto);
}
#add(inStmt, wantRows, fromProto) {
if (this._index !== undefined) {
throw new MisuseError("This BatchStep has already been added to the batch");
}
const stmt = stmtToProto(this._batch._stream._sqlOwner(), inStmt, wantRows);
let condition;
if (this.#conds.length === 0) {
condition = undefined;
}
else if (this.#conds.length === 1) {
condition = this.#conds[0];
}
else {
condition = { type: "and", conds: this.#conds.slice() };
}
const proto = { stmt, condition };
return new Promise((outputCallback, errorCallback) => {
const callback = (stepResult, stepError) => {
if (stepResult !== undefined && stepError !== undefined) {
errorCallback(new ProtoError("Server returned both result and error"));
}
else if (stepError !== undefined) {
errorCallback(errorFromProto(stepError));
}
else if (stepResult !== undefined) {
outputCallback(fromProto(stepResult, this._batch._stream.intMode));
}
else {
outputCallback(undefined);
}
};
this._index = this._batch._steps.length;
this._batch._steps.push({ proto, callback });
});
}
}
export class BatchCond {
/** @private */
_batch;
/** @private */
_proto;
/** @private */
constructor(batch, proto) {
this._batch = batch;
this._proto = proto;
}
/** Create a condition that evaluates to true when the given step executes successfully.
*
* If the given step fails error or is skipped because its condition evaluated to false, this
* condition evaluates to false.
*/
static ok(step) {
return new BatchCond(step._batch, { type: "ok", step: stepIndex(step) });
}
/** Create a condition that evaluates to true when the given step fails.
*
* If the given step succeeds or is skipped because its condition evaluated to false, this condition
* evaluates to false.
*/
static error(step) {
return new BatchCond(step._batch, { type: "error", step: stepIndex(step) });
}
/** Create a condition that is a logical negation of another condition.
*/
static not(cond) {
return new BatchCond(cond._batch, { type: "not", cond: cond._proto });
}
/** Create a condition that is a logical AND of other conditions.
*/
static and(batch, conds) {
for (const cond of conds) {
checkCondBatch(batch, cond);
}
return new BatchCond(batch, { type: "and", conds: conds.map(e => e._proto) });
}
/** Create a condition that is a logical OR of other conditions.
*/
static or(batch, conds) {
for (const cond of conds) {
checkCondBatch(batch, cond);
}
return new BatchCond(batch, { type: "or", conds: conds.map(e => e._proto) });
}
/** Create a condition that evaluates to true when the SQL connection is in autocommit mode (not inside an
* explicit transaction). This requires protocol version 3 or higher.
*/
static isAutocommit(batch) {
batch._stream.client()._ensureVersion(3, "BatchCond.isAutocommit()");
return new BatchCond(batch, { type: "is_autocommit" });
}
}
function stepIndex(step) {
if (step._index === undefined) {
throw new MisuseError("Cannot add a condition referencing a step that has not been added to the batch");
}
return step._index;
}
function checkCondBatch(expectedBatch, cond) {
if (cond._batch !== expectedBatch) {
throw new MisuseError("Cannot mix BatchCond objects for different Batch objects");
}
}