@supabase-cache-helpers/postgrest-filter

PostgREST Filter

This package provides a few utility classes around PostgREST queries.

Installation

pnpm install @supabase-cache-helpers/postgrest-filter

npm install @supabase-cache-helpers/postgrest-filter

yarn add @supabase-cache-helpers/postgrest-filter

PostgrestQueryParser and PostgrestParser

PostgrestQueryParser decompose the select and filter query parameters of a PostgREST query into JSON.

PostgrestParser extends PostgrestQueryParser and extracts all relevant information from a PostrestFilterBuilder instance (schema, table, body, count, head, ...) and parse them into definite keys.

Here is an example:

const p = new PostgrestParser(
      c
        .from("test")
        .select(
          `name,
           city:cities (
            test:name
          ),
          countries (
            capital,
            population,
            some_ref (
              test:first,
              second
            )
          )`,
          { head: false, count: "exact" }
        )
        .or(
          "full_name.eq.20,test.neq.true,and(full_name.eq.Test Name,[e-mail])"
        )
        .eq("id", "123")
        .contains("id", "456")
    );
    console.log(p.bodyKey); // undefined
    console.log(p.count); // exact
    console.log(p.isHead); // false
    console.log(p.queryKey); // id=cs.456&id=eq.123&or=%28full_name.eq.20%2Ctest.neq.true%2Cand%28full_name.eq.Test+Name%2Cemail.eq.test%40mail.com%29%29&select=name%2Ccity%3Acities%28test%3Aname%29%2Ccountries%28capital%2Cpopulation%2Csome_ref%28test%3Afirst%2Csecond%29%29
    console.log(p.schema); // undefined --> default schema
    console.log(p.table); // test
    console.log(p.paths);
    //  [
    //    { alias: undefined, path: "name" },
    //    { alias: "city.test", path: "cities.name" },
    //    { alias: undefined, path: "countries.capital" },
    //    { alias: undefined, path: "countries.population" },
    //    {
    //      alias: "countries.some_ref.test",
    //      path: "countries.some_ref.first",
    //    },
    //    { alias: undefined, path: "countries.some_ref.second" },
    //  ];
    console.log(JSON.stringify(p.filters, null, 2)); 
    // [
    //   {
    //     or: [
    //       {
    //         path: "full_name",
    //         negate: false,
    //         operator: "eq",
    //         value: 20,
    //       },
    //       {
    //         path: "test",
    //         negate: false,
    //         operator: "neq",
    //         value: true,
    //       },
    //       {
    //         and: [
    //           {
    //             path: "full_name",
    //             negate: false,
    //             operator: "eq",
    //             value: "Test Name",
    //           },
    //           {
    //             path: "email",
    //             negate: false,
    //             operator: "eq",
    //             value: "[e-mail]",
    //           },
    //         ],
    //       },
    //     ],
    //   },
    //   {
    //     path: "id",
    //     negate: false,
    //     operator: "eq",
    //     value: 123,
    //   },
    //   {
    //     path: "id",
    //     negate: false,
    //     operator: "cs",
    //     value: 456,
    //   },
    // ];

PostgrestFilter

Use the filters and selected paths extracted from PostgrestQueryParser to build a filter function.

• .hasPaths(input): boolean checks that the input has a value (not undefined) for all .paths
• .applyFilters(input): boolean applies all .filters to the input
• .apply(input): boolean applies both of the above

Here is an example:

const filter = PostgrestFilter.fromFilterBuilder(
    supabase
      .from("contact")
      .select(
        "id,username,ticket_number,golden_ticket,tags,country!inner(code,name,full_name)"
      )
      .or(`username.eq.unknown,and(ticket_number.eq.2,golden_ticket.is.true)`)
      .is("golden_ticket", true)
      .in("username", ["thorwebdev"])
      .contains("tags", ["supateam"])
      .or("name.eq.unknown,and(name.eq.Singapore,code.eq.SG)", {
        foreignTable: "country",
      })
  );
console.log(
  filter.apply({
    id: "68d2e5ef-d117-4f0c-abc7-60891a643571",
    username: "thorwebdev",
    ticket_number: 2,
    golden_ticket: false,
    tags: ["supateam", "investor"],
    country: {
      code: "SG",
      name: "Singapore",
      full_name: "Republic of Singapore",
    },
  })
); // --> false
console.log(
  filter.apply({
    id: "68d2e5ef-d117-4f0c-abc7-60891a643571",
    created_at: "2022-08-19T15:30:33.072441+00:00",
    username: "thorwebdev",
    ticket_number: 2,
    golden_ticket: true,
    tags: ["supateam", "investor"],
    country: {
      code: "SG",
      name: "Singapore",
      full_name: "Republic of Singapore",
    },
  })
); // --> true

Limitations

• When mutating data, we oftentimes do not use the same mapped paths despite it being the same object. Hence, the .hasPath() function should try to transform the input object using the knowledge it has about paths and aliases of the expected obejct.