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@graphile-contrib/pg-omit-archived

This Graphile Engine plugin can be used to give your schema support for "soft-deletes" - where you set an is_archived or is_deleted column to true and expect the record to be omitted by default (but it's still available to be recovered should you need to). It's also useful for hiding certain other classes of records by default, but allowing them to be shown by passing a parameter; for example you could hide drafts via a published_at column and require an explicit includeDrafts: YES setting to show them.

It's possible (and common) to use this plugin multiple times (for different column names/meanings) - when you do so you must use a different keyword for each plugin invocation.

Installing

This requires postgraphile@^4.5.5.

yarn add postgraphile @graphile-contrib/pg-omit-archived

(Or replace yarn add with npm install --save if you use npm.)

Usage

Add a column to your table to indicate whether the record should be skipped over by default or not, and then append this plugin to your PostGraphile options. CLI usage is more restrictive than library usage, so if you want more powerful integration we recommend you use PostGraphile in library (middleware) mode.

Usage - CLI

If you're using the CLI then you must use a boolean is_archived column:

alter table my_table add column is_archived boolean not null default false;

Then append this plugin with --append-plugins:

postgraphile --append-plugins @graphile-contrib/pg-omit-archived -c postgres:///my_db

Usage - Library

IMPORTANT: if a nullable or boolean column is not suitable for your needs, please see the section on expressions below.

If you're using PostGraphile in library (middleware) mode then you have more configuration options and you can specify a column that's either boolean or nullable. A nullable timestamptz column is a popular choice:

alter table my_table add column archived_at timestamptz;

If you're not using a boolean is_archived column then you must specify the column name, which you can do via the pgArchivedColumnName option.

You can also tell the plugin to invert the include/exclude logic with the pgArchivedColumnImpliesVisible option (e.g. if you're using is_published you'd set pgArchivedColumnImpliesVisible: true rather than the default pgArchivedColumnImpliesVisible: false which would be appropriate for is_draft). More information on this below.

Another option is to have the plugin apply to related records with the pgArchivedRelations: true option - more on this below.

When the plugin detects that inheritance is possible, the default for the argument will be set to INHERIT; to disable this behavior, use pgArchivedDefaultInherit: false.

When the default is not INHERIT you can also change the default for includeArchived from NO to YES via pgArchivedDefault: "YES" (another option is EXCLUSIVELY).

Example:

const express = require("express");
const { postgraphile } = require("postgraphile");
const {
  default: PgOmitArchived,
} = require("@graphile-contrib/pg-omit-archived");

const app = express();

app.use(
  postgraphile(process.env.DATABASE_URL, "app_public", {
    /* 👇👇👇 */
    appendPlugins: [PgOmitArchived],
    graphileBuildOptions: {
      pgArchivedColumnName: "is_archived",
      pgArchivedColumnImpliesVisible: false,
      pgArchivedRelations: false,
      pgArchivedDefaultInherit: true,
      pgArchivedDefault: "NO",
    },
    /* ☝️☝️☝️ */
  }),
);

app.listen(process.env.PORT || 3000);

You can also use the plugin multiple times for different columns using the custom(keyword) plugin factory. When you do this you supply a keyword and all of the options are based on this keyword so you can configure each plugin individually (we also look for the column is_${keyword}). For example:

const express = require("express");
const { postgraphile } = require("postgraphile");
const {
  custom: customPgOmitArchived,
} = require("@graphile-contrib/pg-omit-archived");

const app = express();

app.use(
  postgraphile(process.env.DATABASE_URL, "app_public", {
    /* 👇👇👇 */
    appendPlugins: [
      customPgOmitArchived("archived"),
      customPgOmitArchived("deleted"),
      customPgOmitArchived("template"),
      customPgOmitArchived("draft"), // e.g. draft vs published
    ],
    graphileBuildOptions: {
      /* -------- Options for 'archived' -------- */
      // Boolean column -> checked as "IS NOT TRUE":
      pgArchivedColumnName: "is_archived",
      // When true, hide; when false, visible:
      pgArchivedColumnImpliesVisible: false,
      // Only add includeArchived to tables with is_archived column:
      pgArchivedRelations: false,
      // Exclude archived by default
      pgArchivedDefault: "NO",

      /* -------- Options for 'deleted' -------- */
      // Non-boolean column -> checked as "IS NULL":
      pgDeletedColumnName: "deleted_at",
      // Also add includeDeleted to tables which belong to a table with
      // deleted_at column:
      pgArchivedRelations: true,

      /* -------- Options for 'template' -------- */
      pgTemplateColumnName: "is_template",
      // Include templates by default
      pgTemplateDefault: "YES",
      // Don't default to INHERIT even if we could
      pgTemplateDefaultInherit: false,

      /* -------- Options for 'draft' -------- */
      // Column name doesn't have to match keyword name:
      pgDraftColumnName: "is_published",
      // When true -> published -> visible; when false -> unpublished -> hidden
      pgDraftColumnImpliesVisible: true,
    },
    /* ☝️☝️☝️ */
  }),
);

app.listen(process.env.PORT || 3000);

Usage - advanced options

By default we'll look for a column named after your keyword (e.g. if you use the 'deleted' keyword, we'll look for an is_deleted column). You may override the column adding the pg<Keyword>ColumnName: 'my_column_name_here' (e.g. pgDeletedColumnName: 'deleted_at') setting to graphileBuildOptions, where <Keyword> is your keyword with the first character uppercased (see above for examples).

This plugin was built expecting to hide things when true (boolean) or non-null (e.g. nullable timestamp) - this works well for things like is_archived, deleted_at, and is_template. However sometimes you want this inverse of this behaviour; e.g. if your column is published_at you'd want it visible when non-null and hidden when null. To invert the behaviour, add the pg<Keyword>ColumnImpliesVisible: true (e.g. pgDraftColumnImpliesVisible: true) setting to graphileBuildOptions, where <Keyword> is your keyword with the first character uppercased (see above for examples).

By default this plugin only adds the include<Keyword> (e.g. includeArchived) argument to collections for tables that have the relevant (e.g. is_archived) column. Sometimes however you want to expand this behaviour to tables that "belong to" this table. To achieve this, use the pg<Keyword>Relations: true (e.g. pgArchivedRelations: true) option (or for more granular control use the @<keyword>Relation (e.g. @archivedRelation) smart comment/smart tag on the relevant foreign key constraint), and we'll add an argument like includeWhen<Relation><Keyword> (e.g. includeWhenParentByParentIdArchived). You should use this sparingly as it's not implemented particularly efficiently, and it also will make your schema somewhat larger/more complex.

Usage - advanced expressions

If a boolean or nullable column is not sufficient for your needs then since v3.0.0 you can use an expression instead. This allows you to write queries such as my_table.status = 'archived' or my_table.archived_at is not null or my_table.deleted_at is not null or my_table.published_at is null or even my_computed_column(my_table) is true (but be careful with that one; performance would likely be poor!).

To use this, instead of setting pgArchivedColumnName you can specify both:

  • pgArchivedExpression (or pg<Keyword>Expression): a function that accepts sql and tableAlias and returns a pg-sql2 fragment that should resolve to a boolean indicating that the row should be omitted
  • pgArchivedTables (or pg<Keyword>Tables): an array of tables that this expression applies to (since we can't determine this automatically)
app.use(
  postgraphile(process.env.DATABASE_URL, "app_public", {
    appendPlugins: [customPgOmitArchived("archived")],
    graphileBuildOptions: {
      /* 👇👇👇 */
      // What tables does the expression apply to?
      pgArchivedTables: ["my_schema.my_table"],

      // SQL expression that returns true if the row should be omitted
      pgArchivedExpression: (sql, tableAlias) =>
        sql.fragment`${tableAlias}.status = 'archived'`,
      /* ☝️☝️☝️ */
    },
  }),
);

Behaviour

Root level query fields will omit archived records by default.

Plural relation fields on an object will by default be set to INHERIT, which means that if the parent record is archived then all child records will be included; otherwise (if the parent record is NOT archived) only the non-archived child records will be available.

Singular relations and lookups ignore the is_archived column - it's assumed that if you know the exact ID then you're deliberately opting to view the archived record.

This plugin does not prevent people from seeing archived records, it merely prevents them being included by default by various collections so you must opt to see the excluded content.

Assumptions

It's assumed that if a record is archived then all of its children will also be archived. We don't actually care if this is the case or not, and will work regardless, but it's an assumption that we have. It's up to you to enforce this if it makes sense to do so ─ database triggers are a good solution to this.

Thanks

🙏 This plugin was sponsored by https://sprout.io and is used in production.