new(pkg): create a library to manage index configs

Signed-off-by: Lorenzo Susini <[email protected]>

Author: loresuso

pkg/index/config.go

@@ -0,0 +1,105 @@
+// Copyright 2022 The Falco Authors
+//
+// Licensed 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.
+
+package index
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"gopkg.in/yaml.v3"
+)
+
+// ConfigEntry contains information about one of the index that were cached locally.
+// TODO: add support for all the other fields.
+type ConfigEntry struct {
+	AddedTimestamp string `yaml:"added_timestamp"`
+	// CaFile                string `yaml:"caFile"`
+	// CertFile              string `yaml:"certFile"`
+	// InsecureSkipTLSVerify string `yaml:"insecure_skip_tls_verify"`
+	// KeyFile               string `yaml:"keyFile"`
+	Name string `yaml:"name"`
+	// PassCredentialsAll    string `yaml:"pass_credentials_all"`
+	// Password              string `yaml:"password"`
+	UpdatedTimestamp string `yaml:"updated_timestamp"`
+	URL              string `yaml:"url"`
+	// Username              string `yaml:"username"`
+}
+
+// Config aggregates the info about ConfigEntries.
+type Config struct {
+	Configs []ConfigEntry `yaml:"configs"`
+}
+
+// NewConfig loads an index config from a file.
+func NewConfig(path string) (*Config, error) {
+	var config Config
+	file, err := os.ReadFile(filepath.Clean(path))
+	if os.IsNotExist(err) {
+		return &config, nil
+	} else if err != nil {
+		return nil, err
+	}
+
+	err = yaml.Unmarshal(file, &config)
+	if err != nil {
+		return nil, err
+	}
+
+	return &config, nil
+}
+
+// Add adds a new config to Config.
+func (c *Config) Add(entry ConfigEntry) {
+	c.Configs = append(c.Configs, entry)
+}
+
+// Remove removes a config by name from an Config.
+func (c *Config) Remove(name string) error {
+	for k, conf := range c.Configs {
+		if conf.Name == name {
+			c.Configs = append(c.Configs[:k], c.Configs[k+1:]...)
+			return nil
+		}
+	}
+
+	return fmt.Errorf("cannot remove index %s: not found", name)
+}
+
+// Get returns a pointer to an entry in a Config.
+func (c *Config) Get(name string) (*ConfigEntry, error) {
+	for k, conf := range c.Configs {
+		if conf.Name == name {
+			return &c.Configs[k], nil
+		}
+	}
+
+	return nil, fmt.Errorf("not found")
+}
+
+// Write writes an Config to disk.
+func (c *Config) Write(path string) error {
+	data, err := yaml.Marshal(c)
+	if err != nil {
+		return err
+	}
+
+	err = os.WriteFile(path, data, writePermissions)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}

pkg/index/constants.go

@@ -0,0 +1,19 @@
+// Copyright 2022 The Falco Authors
+//
+// Licensed 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.
+
+package index
+
+const (
+	writePermissions = 0o600
+)

pkg/index/doc.go

@@ -0,0 +1,16 @@
+// Copyright 2022 The Falco Authors
+//
+// Licensed 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.
+
+// Package index implements all the logic for handling indexes.
+package index