agsamantha/node_modules/@langchain/community/dist/structured_query/supabase.js
2024-10-02 15:15:21 -05:00

267 lines
10 KiB
JavaScript

import { isFilterEmpty, isFloat, isInt, isObject, isString, BaseTranslator, Comparators, Operators, } from "@langchain/core/structured_query";
import { ProxyParamsDuplicator, convertObjectFilterToStructuredQuery, } from "./supabase_utils.js";
/**
* A specialized translator designed to work with Supabase, extending the
* BaseTranslator class. It translates structured queries into a format
* that can be understood by the Supabase database.
* @example
* ```typescript
* const selfQueryRetriever = new SelfQueryRetriever({
* llm: new ChatOpenAI(),
* vectorStore: new SupabaseVectorStore(),
* documentContents: "Brief summary of a movie",
* attributeInfo: [],
* structuredQueryTranslator: new SupabaseTranslator(),
* });
*
* const queryResult = await selfQueryRetriever.getRelevantDocuments(
* "Which movies are directed by Greta Gerwig?",
* );
* ```
*/
export class SupabaseTranslator extends BaseTranslator {
constructor() {
super(...arguments);
Object.defineProperty(this, "allowedOperators", {
enumerable: true,
configurable: true,
writable: true,
value: [Operators.and, Operators.or]
});
Object.defineProperty(this, "allowedComparators", {
enumerable: true,
configurable: true,
writable: true,
value: [
Comparators.eq,
Comparators.ne,
Comparators.gt,
Comparators.gte,
Comparators.lt,
Comparators.lte,
]
});
}
formatFunction() {
throw new Error("Not implemented");
}
/**
* Returns a function that applies the appropriate comparator operation on
* the attribute and value provided. The function returned is used to
* filter data in a Supabase database.
* @param comparator The comparator to be used in the operation.
* @returns A function that applies the comparator operation on the attribute and value provided.
*/
getComparatorFunction(comparator) {
switch (comparator) {
case Comparators.eq: {
return (attr, value) => (rpc) => rpc.eq(this.buildColumnName(attr, value), value);
}
case Comparators.ne: {
return (attr, value) => (rpc) => rpc.neq(this.buildColumnName(attr, value), value);
}
case Comparators.gt: {
return (attr, value) => (rpc) => rpc.gt(this.buildColumnName(attr, value), value);
}
case Comparators.gte: {
return (attr, value) => (rpc) => rpc.gte(this.buildColumnName(attr, value), value);
}
case Comparators.lt: {
return (attr, value) => (rpc) => rpc.lt(this.buildColumnName(attr, value), value);
}
case Comparators.lte: {
return (attr, value) => (rpc) => rpc.lte(this.buildColumnName(attr, value), value);
}
default: {
throw new Error("Unknown comparator");
}
}
}
/**
* Builds a column name based on the attribute and value provided. The
* column name is used in filtering data in a Supabase database.
* @param attr The attribute to be used in the column name.
* @param value The value to be used in the column name.
* @param includeType Whether to include the data type in the column name.
* @returns The built column name.
*/
buildColumnName(attr, value, includeType = true) {
let column = "";
if (isString(value)) {
column = `metadata->>${attr}`;
}
else if (isInt(value)) {
column = `metadata->${attr}${includeType ? "::int" : ""}`;
}
else if (isFloat(value)) {
column = `metadata->${attr}${includeType ? "::float" : ""}`;
}
else {
throw new Error("Data type not supported");
}
return column;
}
/**
* Visits an operation and returns a string representation of it. This is
* used in translating a structured query into a format that can be
* understood by Supabase.
* @param operation The operation to be visited.
* @returns A string representation of the operation.
*/
visitOperationAsString(operation) {
const { args } = operation;
if (!args) {
return "";
}
return args
?.reduce((acc, arg) => {
if (arg.exprName === "Comparison") {
acc.push(this.visitComparisonAsString(arg));
}
else if (arg.exprName === "Operation") {
const { operator: innerOperator } = arg;
acc.push(`${innerOperator}(${this.visitOperationAsString(arg)})`);
}
return acc;
}, [])
.join(",");
}
/**
* Visits an operation and returns a function that applies the operation
* on a Supabase database. This is used in translating a structured query
* into a format that can be understood by Supabase.
* @param operation The operation to be visited.
* @returns A function that applies the operation on a Supabase database.
*/
visitOperation(operation) {
const { operator, args } = operation;
if (this.allowedOperators.includes(operator)) {
if (operator === Operators.and) {
if (!args) {
return (rpc) => rpc;
}
const filter = (rpc) => args.reduce((acc, arg) => {
const filter = arg.accept(this);
return filter(acc);
}, rpc);
return filter;
}
else if (operator === Operators.or) {
return (rpc) => rpc.or(this.visitOperationAsString(operation));
}
else {
throw new Error("Unknown operator");
}
}
else {
throw new Error("Operator not allowed");
}
}
/**
* Visits a comparison and returns a string representation of it. This is
* used in translating a structured query into a format that can be
* understood by Supabase.
* @param comparison The comparison to be visited.
* @returns A string representation of the comparison.
*/
visitComparisonAsString(comparison) {
let { value } = comparison;
const { comparator: _comparator, attribute } = comparison;
let comparator = _comparator;
if (comparator === Comparators.ne) {
comparator = "neq";
}
if (Array.isArray(value)) {
value = `(${value
.map((v) => {
if (typeof v === "string" && /[,()]/.test(v))
return `"${v}"`;
return v;
})
.join(",")})`;
}
return `${this.buildColumnName(attribute, value, false)}.${comparator}.${value}}`;
}
/**
* Visits a comparison and returns a function that applies the comparison
* on a Supabase database. This is used in translating a structured query
* into a format that can be understood by Supabase.
* @param comparison The comparison to be visited.
* @returns A function that applies the comparison on a Supabase database.
*/
visitComparison(comparison) {
const { comparator, attribute, value } = comparison;
if (this.allowedComparators.includes(comparator)) {
const comparatorFunction = this.getComparatorFunction(comparator);
return comparatorFunction(attribute, value);
}
else {
throw new Error("Comparator not allowed");
}
}
/**
* Visits a structured query and returns a function that applies the query
* on a Supabase database. This is used in translating a structured query
* into a format that can be understood by Supabase.
* @param query The structured query to be visited.
* @returns A function that applies the query on a Supabase database.
*/
visitStructuredQuery(query) {
if (!query.filter) {
return {};
}
const filterFunction = query.filter?.accept(this);
return { filter: filterFunction ?? {} };
}
/**
* Merges two filters into one. The merged filter can be used to filter
* data in a Supabase database.
* @param defaultFilter The default filter to be merged.
* @param generatedFilter The generated filter to be merged.
* @param mergeType The type of merge to be performed. It can be 'and', 'or', or 'replace'.
* @returns The merged filter.
*/
mergeFilters(defaultFilter, generatedFilter, mergeType = "and") {
if (isFilterEmpty(defaultFilter) && isFilterEmpty(generatedFilter)) {
return undefined;
}
if (isFilterEmpty(defaultFilter) || mergeType === "replace") {
if (isFilterEmpty(generatedFilter)) {
return undefined;
}
return generatedFilter;
}
if (isFilterEmpty(generatedFilter)) {
if (mergeType === "and") {
return undefined;
}
return defaultFilter;
}
let myDefaultFilter = defaultFilter;
if (isObject(defaultFilter)) {
const { filter } = this.visitStructuredQuery(convertObjectFilterToStructuredQuery(defaultFilter));
// just in case the built filter is empty somehow
if (isFilterEmpty(filter)) {
if (isFilterEmpty(generatedFilter)) {
return undefined;
}
return generatedFilter;
}
myDefaultFilter = filter;
}
// After this point, myDefaultFilter will always be SupabaseFilterRPCCall
if (mergeType === "or") {
return (rpc) => {
const defaultFlattenedParams = ProxyParamsDuplicator.getFlattenedParams(rpc, myDefaultFilter);
const generatedFlattenedParams = ProxyParamsDuplicator.getFlattenedParams(rpc, generatedFilter);
return rpc.or(`${defaultFlattenedParams},${generatedFlattenedParams}`);
};
}
else if (mergeType === "and") {
return (rpc) => generatedFilter(myDefaultFilter(rpc));
}
else {
throw new Error("Unknown merge type");
}
}
}