repository_memory.go

// Copyright © 2023 Ory Corp
// SPDX-License-Identifier: Apache-2.0

package rule

import (
	"context"
	"net/http"
	"net/url"
	"sync"

	"github.com/pkg/errors"

	"github.com/ory/oathkeeper/driver/configuration"
	"github.com/ory/oathkeeper/helper"
	"github.com/ory/oathkeeper/x"

	"github.com/ory/x/pagination"
)

var _ Repository = new(RepositoryMemory)

type repositoryMemoryRegistry interface {
	RuleValidator() Validator
	x.RegistryLogger
}

type RepositoryMemory struct {
	sync.RWMutex
	rules            []Rule
	invalidRules     []Rule
	matchingStrategy configuration.MatchingStrategy
	r                repositoryMemoryRegistry
}

// MatchingStrategy returns current MatchingStrategy.
func (m *RepositoryMemory) MatchingStrategy(_ context.Context) (configuration.MatchingStrategy, error) {
	m.RLock()
	defer m.RUnlock()
	return m.matchingStrategy, nil
}

// SetMatchingStrategy updates MatchingStrategy.
func (m *RepositoryMemory) SetMatchingStrategy(_ context.Context, ms configuration.MatchingStrategy) error {
	m.Lock()
	defer m.Unlock()
	m.matchingStrategy = ms
	return nil
}

func NewRepositoryMemory(r repositoryMemoryRegistry) *RepositoryMemory {
	return &RepositoryMemory{
		r:     r,
		rules: make([]Rule, 0),
	}
}

// WithRules sets rules without validation. For testing only.
func (m *RepositoryMemory) WithRules(rules []Rule) {
	m.Lock()
	m.rules = rules
	m.Unlock()
}

func (m *RepositoryMemory) Count(ctx context.Context) (int, error) {
	m.RLock()
	defer m.RUnlock()

	return len(m.rules), nil
}

func (m *RepositoryMemory) List(ctx context.Context, limit, offset int) ([]Rule, error) {
	m.RLock()
	defer m.RUnlock()

	start, end := pagination.Index(limit, offset, len(m.rules))
	return m.rules[start:end], nil
}

func (m *RepositoryMemory) Get(ctx context.Context, id string) (*Rule, error) {
	m.RLock()
	defer m.RUnlock()

	for _, r := range m.rules {
		if r.ID == id {
			return &r, nil
		}
	}

	return nil, errors.WithStack(helper.ErrResourceNotFound)
}

func (m *RepositoryMemory) Set(ctx context.Context, rules []Rule) error {
	m.Lock()
	defer m.Unlock()

	m.rules = make([]Rule, 0, len(rules))
	m.invalidRules = make([]Rule, 0)

	for _, check := range rules {
		if err := m.r.RuleValidator().Validate(&check); err != nil {
			m.r.Logger().WithError(err).WithField("rule_id", check.ID).
				Errorf("A Rule uses a malformed configuration and all URLs matching this rule will not work. You should resolve this issue now.")
			m.invalidRules = append(m.invalidRules, check)
		} else {
			m.rules = append(m.rules, check)
		}
	}

	return nil
}

func (m *RepositoryMemory) Match(ctx context.Context, method string, u *url.URL, headers http.Header, protocol Protocol) (*Rule, error) {
	if u == nil {
		return nil, errors.WithStack(errors.New("nil URL provided"))
	}

	m.Lock()
	defer m.Unlock()

	var rules []*Rule
	for k := range m.rules {
		r := &m.rules[k]
		if matched, err := r.IsMatching(m.matchingStrategy, method, u, headers, protocol); err != nil {
			return nil, errors.WithStack(err)
		} else if matched {
			rules = append(rules, r)
		}
	}
	for k := range m.invalidRules {
		r := &m.invalidRules[k]
		if matched, err := r.IsMatching(m.matchingStrategy, method, u, headers, protocol); err != nil {
			return nil, errors.WithStack(err)
		} else if matched {
			rules = append(rules, r)
		}
	}

	if len(rules) == 0 {
		return nil, errors.WithStack(helper.ErrMatchesNoRule)
	} else if len(rules) != 1 {
		return nil, errors.WithStack(helper.ErrMatchesMoreThanOneRule)
	}

	return rules[0], nil
}

func (m *RepositoryMemory) ReadyChecker(r *http.Request) error {
	c, err := m.Count(r.Context())
	if err != nil {
		return err
	}
	if c == 0 {
		return errors.WithStack(helper.ErrResourceNotFound.WithReason("No rules found."))
	}
	return nil
}