roryqi commented on code in PR #10883: URL: https://github.com/apache/gravitino/pull/10883#discussion_r3154267324
########## design-docs/gravitino-local-idp.md: ########## @@ -0,0 +1,574 @@ +<!-- + Licensed to the Apache Software Foundation (ASF) under one + or more contributor license agreements. See the NOTICE file + distributed with this work for additional information + regarding copyright ownership. The ASF licenses this file + to you 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. +--> + +# Design of Local IDP Support in Gravitino + +## 1. Background + +Apache Gravitino already has mature support for OAuth 2.0 authentication. Today, Gravitino acts as +an OAuth 2.0 client and delegates authentication to an external identity provider (IdP), typically +using the Client Credentials flow together with Bearer JWT. + +This model works well in enterprise deployments where an external IdP such as Okta, Azure AD, or +Keycloak already exists. However, it introduces friction in several important scenarios: + +- **POC and demo environments**: users want to start Gravitino in minutes, without first deploying + and configuring a dedicated IdP. +- **Offline or isolated environments**: air-gapped, edge, or embedded deployments may not have + access to an external identity service. +- **Data sovereignty requirements**: some organizations do not allow identity information to be + managed by an external service. +- **Operational simplicity**: small deployments may not want the cost and maintenance burden of a + separate OAuth server. + +To address these cases, Gravitino should provide an optional built-in local IdP mode with a simple +username/password authentication flow. + +--- + +## 2. Goals + +1. **Lower the barrier to entry**: allow users to evaluate and use Gravitino without deploying an + external IdP. + +2. **Support self-contained deployments**: provide a fully local authentication mechanism for + offline, air-gapped, and privacy-sensitive environments. + +3. **Keep the design intentionally simple**: optimize for POC and small deployment scenarios rather + than building a full-featured general-purpose identity platform. + +4. **Avoid vendor lock-in**: let users run Gravitino in environments where third-party IdPs are + impractical, undesirable, or cost-prohibitive. + +--- + +## 3. Proposal + +### 3.1 Authentication Model + +The local IdP is introduced as a new Gravitino authenticator mode: **basic**. + +When enabled, Gravitino authenticates incoming requests through HTTP Basic authentication: + +```text +Authorization: Basic <base64(username:password)> +``` + +This mode is intended for quick-start deployments and isolated environments. It should work out of +the box with a minimal configuration and without any dependency on an external identity system. + +### 3.2 Why Basic Authentication + +The surveyed systems show that local authentication support typically converges on +username/password-based flows. For Gravitino, simplicity matters more than protocol richness: + +- it shortens time-to-first-use, +- it is easy to explain and operate, +- it fits POC and offline scenarios well, +- and it avoids introducing token lifecycle complexity into the server. + +For these reasons, the initial local IdP implementation uses: + +| Item | Decision | +|---|---| +| Credential type | Username / password | +| Password storage | Database | +| Local token support | No | +| Recommended deployment scope | POC, offline, and isolated scenarios | + +### 3.3 Why Database Storage + +Passwords and user/group metadata should be stored in the Gravitino relational store rather than in +files: + +- **File-based storage** requires a server restart to add users or rotate passwords. +- **Database storage** supports normal metadata-style CRUD operations and matches Gravitino's + existing persistence model. + +Database-backed storage is the most practical choice for a built-in local IdP. + +--- + +## 4. Password Hashing + +User credentials must never be stored in plaintext. Passwords are stored as password hashes in the +database. + +Among the common password hashing algorithms, **Argon2id** is the recommended choice for +Gravitino. + +| Algorithm | Status | +|---|---| +| Argon2id | Recommended default | + +The initial design uses **Argon2id** as the only supported algorithm, which keeps the +implementation simple while aligning with modern password storage recommendations. + +To make this implementable, the password hashing design should also define the storage and +dependency model explicitly: + +- introduce one dedicated server-side password-hashing dependency that supports Argon2id +- store the full Argon2id hash string in `password_hash`, including algorithm marker, parameters, + salt, and hash output +- use a self-describing format so future parameter tuning does not require schema changes + +For example, `password_hash` should store a PHC-style string such as: + +```text +$argon2id$v=19$m=65536,t=3,p=1$<salt>$<hash> +``` + +This keeps verification logic simple and allows future upgrades of Argon2id cost parameters without +introducing additional columns. + +--- + +## 5. Data Model + +The local IdP requires three new tables: + +1. `local_user_meta` — local user records +2. `local_group_meta` — local group records +3. `local_group_user_rel` — user/group membership mapping + +These tables follow Gravitino's existing metadata table conventions: + +- numeric primary keys, +- `audit_info`, +- optimistic version fields, +- and `deleted_at` for soft deletion. + +Unlike Gravitino's existing `user_meta` and `group_meta` tables, `local_user_meta` and +`local_group_meta` are intentionally designed as **global identity tables** and therefore **do not +contain `metalake_id`**. The purpose of these tables is to store local authentication identities +and credentials once at the server level, instead of duplicating the same login identity in every +metalake. + +### 5.1 `local_user_meta` + +```sql +CREATE TABLE IF NOT EXISTS `local_user_meta` ( + `user_id` BIGINT(20) UNSIGNED NOT NULL COMMENT 'user id', + `user_name` VARCHAR(128) NOT NULL COMMENT 'username', + `password_hash` VARCHAR(256) NOT NULL COMMENT 'hashed password', + `audit_info` MEDIUMTEXT NOT NULL COMMENT 'user audit info', + `current_version` INT UNSIGNED NOT NULL DEFAULT 1 COMMENT 'user current version', + `last_version` INT UNSIGNED NOT NULL DEFAULT 1 COMMENT 'user last version', + `deleted_at` BIGINT(20) UNSIGNED NOT NULL DEFAULT 0 COMMENT 'user deleted at', + PRIMARY KEY (`user_id`), + UNIQUE KEY `uk_un_del` (`user_name`, `deleted_at`) +) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin COMMENT 'local user metadata'; +``` + +### 5.2 `local_group_meta` + +```sql +CREATE TABLE IF NOT EXISTS `local_group_meta` ( + `group_id` BIGINT(20) UNSIGNED NOT NULL COMMENT 'group id', + `group_name` VARCHAR(128) NOT NULL COMMENT 'group name', + `audit_info` MEDIUMTEXT NOT NULL COMMENT 'group audit info', + `current_version` INT UNSIGNED NOT NULL DEFAULT 1 COMMENT 'group current version', + `last_version` INT UNSIGNED NOT NULL DEFAULT 1 COMMENT 'group last version', + `deleted_at` BIGINT(20) UNSIGNED NOT NULL DEFAULT 0 COMMENT 'group deleted at', + PRIMARY KEY (`group_id`), + UNIQUE KEY `uk_gn_del` (`group_name`, `deleted_at`) +) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin COMMENT 'local group metadata'; +``` + +### 5.3 `local_group_user_rel` + +```sql +CREATE TABLE IF NOT EXISTS `local_group_user_rel` ( + `id` BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT COMMENT 'auto increment id', + `group_id` BIGINT(20) UNSIGNED NOT NULL COMMENT 'local group id', + `user_id` BIGINT(20) UNSIGNED NOT NULL COMMENT 'local user id', + `audit_info` MEDIUMTEXT NOT NULL COMMENT 'relation audit info', + `current_version` INT UNSIGNED NOT NULL DEFAULT 1 COMMENT 'relation current version', + `last_version` INT UNSIGNED NOT NULL DEFAULT 1 COMMENT 'relation last version', + `deleted_at` BIGINT(20) UNSIGNED NOT NULL DEFAULT 0 COMMENT 'relation deleted at', Review Comment: Could u point out which you added to the document? -- This is an automated message from the Apache Git Service. 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