Larger restructuring

6 files changed, 637 insertions, 0 deletions

diff --git a/pkg/config/config.go b/pkg/config/config.go
new file mode 100644
index 0000000..83c952f
--- /dev/null
+++ b/pkg/config/config.go
@@ -0,0 +1,137 @@
+package config
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"os/user"
+	"runtime"
+	"runtime/debug"
+	"strings"
+
+	"github.com/Necoro/feed2imap-go/pkg/log"
+	"github.com/Necoro/feed2imap-go/pkg/util"
+)
+
+// Convenience type for the non-mapped configuration options
+// Mostly used for legacy options
+type Map map[string]interface{}
+
+// Global options, not feed specific
+type GlobalOptions struct {
+	Timeout      int      `yaml:"timeout"`
+	DefaultEmail string   `yaml:"default-email"`
+	Target       string   `yaml:"target"`
+	Parts        []string `yaml:"parts"`
+}
+
+// Default global options
+var DefaultGlobalOptions = GlobalOptions{
+	Timeout:      30,
+	DefaultEmail: username() + "@" + hostname(),
+	Target:       "",
+	Parts:        []string{"text", "html"},
+}
+
+// Per feed options
+type Options struct {
+	MinFreq    *int  `yaml:"min-frequency"`
+	InclImages *bool `yaml:"include-images"`
+}
+
+// Default feed options
+var DefaultFeedOptions Options
+
+func init() {
+	one := 1
+	fal := false
+	DefaultFeedOptions = Options{
+		MinFreq:    &one,
+		InclImages: &fal,
+	}
+}
+
+// Config holds the global configuration options and the configured feeds
+type Config struct {
+	GlobalOptions `yaml:",inline"`
+	GlobalConfig  Map     `yaml:",inline"`
+	FeedOptions   Options `yaml:"options"`
+	Feeds         Feeds   `yaml:"-"`
+}
+
+// WithDefault returns a configuration initialized with default values.
+func WithDefault() *Config {
+	return &Config{
+		GlobalOptions: DefaultGlobalOptions,
+		FeedOptions:   DefaultFeedOptions,
+		GlobalConfig:  Map{},
+		Feeds:         Feeds{},
+	}
+}
+
+// Validates the configuration against common mistakes
+func (cfg *Config) Validate() error {
+	if cfg.Target == "" {
+		return fmt.Errorf("No target set!")
+	}
+
+	return nil
+}
+
+// Marks whether 'text' part should be included in mails
+func (cfg *Config) WithPartText() bool {
+	return util.StrContains(cfg.Parts, "text")
+}
+
+// Marks whether 'html' part should be included in mails
+func (cfg *Config) WithPartHtml() bool {
+	return util.StrContains(cfg.Parts, "html")
+}
+
+// Current feed2imap version
+func Version() string {
+	bi, ok := debug.ReadBuildInfo()
+	if !ok {
+		return "(unknown)"
+	}
+	return bi.Main.Version
+}
+
+// Load configuration from file
+func Load(path string) (*Config, error) {
+	log.Printf("Reading configuration file '%s'", path)
+
+	buf, err := ioutil.ReadFile(path)
+	if err != nil {
+		return nil, fmt.Errorf("while reading '%s': %w", path, err)
+	}
+
+	cfg := WithDefault()
+	if err = cfg.parse(buf); err != nil {
+		return nil, fmt.Errorf("while parsing: %w", err)
+	}
+
+	return cfg, nil
+}
+
+func hostname() (hostname string) {
+	hostname, err := os.Hostname()
+	if err != nil {
+		hostname = "localhost"
+	}
+	return
+}
+
+func username() string {
+	u, err := user.Current()
+	switch {
+	case err != nil:
+		return "user"
+	case runtime.GOOS == "windows":
+		// the domain is attached -- remove it again
+		split := strings.Split(u.Username, "\\")
+		return split[len(split)-1]
+	default:
+		return u.Username
+	}
+}
diff --git a/pkg/config/feed.go b/pkg/config/feed.go
new file mode 100644
index 0000000..03494d3
--- /dev/null
+++ b/pkg/config/feed.go
@@ -0,0 +1,38 @@
+package config
+
+import (
+	"fmt"
+	"strings"
+)
+
+// One stored feed
+type Feed struct {
+	Name    string
+	Target  []string `yaml:"-"`
+	Url     string
+	Options `yaml:",inline"`
+}
+
+// Convenience type for all feeds
+type Feeds map[string]Feed
+
+func (feeds Feeds) String() string {
+	var b strings.Builder
+	app := func(a ...interface{}) {
+		_, _ = fmt.Fprint(&b, a...)
+	}
+	app("Feeds [")
+
+	first := true
+	for k, v := range feeds {
+		if !first {
+			app(", ")
+		}
+		app(`"`, k, `"`, ": ")
+		_, _ = fmt.Fprintf(&b, "%+v", v)
+		first = false
+	}
+	app("]")
+
+	return b.String()
+}
diff --git a/pkg/config/yaml.go b/pkg/config/yaml.go
new file mode 100644
index 0000000..53d4d98
--- /dev/null
+++ b/pkg/config/yaml.go
@@ -0,0 +1,120 @@
+package config
+
+import (
+	"fmt"
+
+	"gopkg.in/yaml.v3"
+)
+
+type config struct {
+	*Config      `yaml:",inline"`
+	GlobalConfig Map `yaml:",inline"` // need to be duplicated, because the Map in Config is not filled
+	Feeds        []configGroupFeed
+}
+
+type group struct {
+	Group string
+	Feeds []configGroupFeed
+}
+
+type configGroupFeed struct {
+	Target *string
+	Feed   Feed  `yaml:",inline"`
+	Group  group `yaml:",inline"`
+}
+
+func (grpFeed *configGroupFeed) isGroup() bool {
+	return grpFeed.Group.Group != ""
+}
+
+func (grpFeed *configGroupFeed) isFeed() bool {
+	return grpFeed.Feed.Name != "" || grpFeed.Feed.Url != ""
+}
+
+func (grpFeed *configGroupFeed) target() string {
+	if grpFeed.Target != nil {
+		return *grpFeed.Target
+	}
+	if grpFeed.Feed.Name != "" {
+		return grpFeed.Feed.Name
+	}
+
+	return grpFeed.Group.Group
+}
+
+func unmarshal(buf []byte, cfg *Config) (config, error) {
+	parsedCfg := config{Config: cfg}
+
+	if err := yaml.Unmarshal(buf, &parsedCfg); err != nil {
+		return config{}, err
+	}
+	//fmt.Printf("--- parsedCfg:\n%+v\n\n", parsedCfg)
+
+	if parsedCfg.GlobalConfig == nil {
+		cfg.GlobalConfig = Map{}
+	} else {
+		cfg.GlobalConfig = parsedCfg.GlobalConfig // need to copy the map explicitly
+	}
+
+	return parsedCfg, nil
+}
+
+func (cfg *Config) parse(buf []byte) error {
+	var (
+		err       error
+		parsedCfg config
+	)
+
+	if parsedCfg, err = unmarshal(buf, cfg); err != nil {
+		return fmt.Errorf("while unmarshalling: %w", err)
+	}
+
+	if err := buildFeeds(parsedCfg.Feeds, []string{}, cfg.Feeds); err != nil {
+		return fmt.Errorf("while parsing: %w", err)
+	}
+
+	return nil
+}
+
+func appTarget(target []string, app string) []string {
+	switch {
+	case len(target) == 0 && app == "":
+		return []string{}
+	case len(target) == 0:
+		return []string{app}
+	case app == "":
+		return target
+	default:
+		return append(target, app)
+	}
+}
+
+// Fetch the group structure and populate the `Target` fields in the feeds
+func buildFeeds(cfg []configGroupFeed, target []string, feeds Feeds) error {
+	for _, f := range cfg {
+		target := appTarget(target, f.target())
+		switch {
+		case f.isFeed() && f.isGroup():
+			return fmt.Errorf("Entry with Target %s is both a Feed and a group", target)
+
+		case f.isFeed():
+			name := f.Feed.Name
+			if name == "" {
+				return fmt.Errorf("Unnamed feed")
+			}
+
+			if _, ok := feeds[name]; ok {
+				return fmt.Errorf("Duplicate Feed Name '%s'", name)
+			}
+			f.Feed.Target = target
+			feeds[name] = f.Feed
+
+		case f.isGroup():
+			if err := buildFeeds(f.Group.Feeds, target, feeds); err != nil {
+				return err
+			}
+		}
+	}
+
+	return nil
+}
diff --git a/pkg/config/yaml_test.go b/pkg/config/yaml_test.go
new file mode 100644
index 0000000..501ead3
--- /dev/null
+++ b/pkg/config/yaml_test.go
@@ -0,0 +1,284 @@
+package config
+
+import (
+	"reflect"
+	"strings"
+	"testing"
+
+	"github.com/davecgh/go-spew/spew"
+)
+
+func i(i int) *int       { return &i }
+func s(s string) *string { return &s }
+func b(b bool) *bool     { return &b }
+func t(s string) []string {
+	if s == "" {
+		return []string{}
+	}
+	return strings.Split(s, ".")
+}
+
+func TestBuildFeeds(tst *testing.T) {
+	tests := []struct {
+		name    string
+		wantErr bool
+		target  string
+		feeds   []configGroupFeed
+		result  Feeds
+	}{
+		{name: "Empty input", wantErr: false, target: "", feeds: nil, result: Feeds{}},
+		{name: "Empty Feed", wantErr: true, target: "",
+			feeds: []configGroupFeed{
+				{Target: s("foo"), Feed: Feed{Url: "google.de"}},
+			}, result: Feeds{}},
+		{name: "Empty Feed", wantErr: true, target: "",
+			feeds: []configGroupFeed{
+				{Target: nil, Feed: Feed{Url: "google.de"}},
+			}, result: Feeds{}},
+		{name: "Duplicate Feed Name", wantErr: true, target: "",
+			feeds: []configGroupFeed{
+				{Target: nil, Feed: Feed{Name: "Dup"}},
+				{Target: nil, Feed: Feed{Name: "Dup"}},
+			}, result: Feeds{}},
+		{name: "Simple", wantErr: false, target: "",
+			feeds: []configGroupFeed{
+				{Target: s("foo"), Feed: Feed{Name: "muh"}},
+			},
+			result: Feeds{"muh": Feed{Name: "muh", Target: t("foo")}},
+		},
+		{name: "Simple With Target", wantErr: false, target: "moep",
+			feeds: []configGroupFeed{
+				{Target: s("foo"), Feed: Feed{Name: "muh"}},
+			},
+			result: Feeds{"muh": Feed{Name: "muh", Target: t("moep.foo")}},
+		},
+		{name: "Simple With Nil Target", wantErr: false, target: "moep",
+			feeds: []configGroupFeed{
+				{Target: nil, Feed: Feed{Name: "muh"}},
+			},
+			result: Feeds{"muh": Feed{Name: "muh", Target: t("moep.muh")}},
+		},
+		{name: "Simple With Empty Target", wantErr: false, target: "moep",
+			feeds: []configGroupFeed{
+				{Target: s(""), Feed: Feed{Name: "muh"}},
+			},
+			result: Feeds{"muh": Feed{Name: "muh", Target: t("moep")}},
+		},
+		{name: "Multiple Feeds", wantErr: false, target: "moep",
+			feeds: []configGroupFeed{
+				{Target: s("foo"), Feed: Feed{Name: "muh"}},
+				{Target: nil, Feed: Feed{Name: "bar"}},
+			},
+			result: Feeds{
+				"muh": Feed{Name: "muh", Target: t("moep.foo")},
+				"bar": Feed{Name: "bar", Target: t("moep.bar")},
+			},
+		},
+		{name: "Empty Group", wantErr: false, target: "",
+			feeds: []configGroupFeed{
+				{Target: nil, Group: group{Group: "G1"}},
+			},
+			result: Feeds{},
+		},
+		{name: "Simple Group", wantErr: false, target: "",
+			feeds: []configGroupFeed{
+				{Target: nil, Group: group{Group: "G1", Feeds: []configGroupFeed{
+					{Target: s("bar"), Feed: Feed{Name: "F1"}},
+					{Target: s(""), Feed: Feed{Name: "F2"}},
+					{Target: nil, Feed: Feed{Name: "F3"}},
+				}}},
+			},
+			result: Feeds{
+				"F1": Feed{Name: "F1", Target: t("G1.bar")},
+				"F2": Feed{Name: "F2", Target: t("G1")},
+				"F3": Feed{Name: "F3", Target: t("G1.F3")},
+			},
+		},
+		{name: "Nested Groups", wantErr: false, target: "",
+			feeds: []configGroupFeed{
+				{Target: nil, Group: group{Group: "G1", Feeds: []configGroupFeed{
+					{Target: nil, Feed: Feed{Name: "F0"}},
+					{Target: s("bar"), Group: group{Group: "G2",
+						Feeds: []configGroupFeed{{Target: nil, Feed: Feed{Name: "F1"}}}}},
+					{Target: s(""), Group: group{Group: "G3",
+						Feeds: []configGroupFeed{{Target: s("baz"), Feed: Feed{Name: "F2"}}}}},
+					{Target: nil, Group: group{Group: "G4",
+						Feeds: []configGroupFeed{{Target: nil, Feed: Feed{Name: "F3"}}}}},
+				}}},
+			},
+			result: Feeds{
+				"F0": Feed{Name: "F0", Target: t("G1.F0")},
+				"F1": Feed{Name: "F1", Target: t("G1.bar.F1")},
+				"F2": Feed{Name: "F2", Target: t("G1.baz")},
+				"F3": Feed{Name: "F3", Target: t("G1.G4.F3")},
+			},
+		},
+	}
+	for _, tt := range tests {
+		tst.Run(tt.name, func(tst *testing.T) {
+			var feeds = Feeds{}
+			err := buildFeeds(tt.feeds, t(tt.target), feeds)
+			if (err != nil) != tt.wantErr {
+				tst.Errorf("buildFeeds() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if !tt.wantErr && !reflect.DeepEqual(feeds, tt.result) {
+				tst.Errorf("buildFeeds() got: %s\nwant: %s", spew.Sdump(feeds), spew.Sdump(tt.result))
+			}
+		})
+	}
+}
+
+func defaultConfig(feeds []configGroupFeed, global Map) config {
+	defCfg := WithDefault()
+	if global != nil {
+		defCfg.GlobalConfig = global
+	}
+	return config{
+		Config:       defCfg,
+		Feeds:        feeds,
+		GlobalConfig: global,
+	}
+}
+
+//noinspection GoNilness,GoNilness
+func TestUnmarshal(tst *testing.T) {
+	tests := []struct {
+		name    string
+		inp     string
+		wantErr bool
+		config  config
+	}{
+		{name: "Empty",
+			inp: "", wantErr: false, config: defaultConfig(nil, nil)},
+		{name: "Trash", inp: "Something", wantErr: true},
+		{name: "Simple config",
+			inp: "something: 1\nsomething_else: 2", wantErr: false, config: defaultConfig(nil, Map{"something": 1, "something_else": 2})},
+		{name: "Known config",
+			inp: "whatever: 2\ndefault-email: foo@foobar.de\ntimeout: 60\nsomething: 1", wantErr: false, config: func() config {
+				c := defaultConfig(nil, Map{"something": 1, "whatever": 2})
+				c.Timeout = 60
+				c.DefaultEmail = "foo@foobar.de"
+				return c
+			}()},
+		{name: "Known config with feed-options",
+			inp: "whatever: 2\ntimeout: 60\noptions:\n  min-frequency: 6", wantErr: false, config: func() config {
+				c := defaultConfig(nil, Map{"whatever": 2})
+				c.Timeout = 60
+				c.FeedOptions.MinFreq = i(6)
+				return c
+			}()},
+		{name: "Config with feed",
+			inp: `
+something: 1
+feeds:
+   - name: Foo
+     url: whatever
+     target: bar
+     include-images: true
+     unknown-option: foo
+`,
+			wantErr: false,
+			config: defaultConfig([]configGroupFeed{
+				{Target: s("bar"), Feed: Feed{
+					Name: "Foo",
+					Url:  "whatever",
+					Options: Options{
+						MinFreq:    nil,
+						InclImages: b(true),
+					},
+				}}}, Map{"something": 1})},
+
+		{name: "Feeds",
+			inp: `
+feeds:
+   - name: Foo
+     url: whatever
+     min-frequency: 2
+   - name: Shrubbery
+     url: google.de
+     target: bla
+     include-images: false
+`,
+			wantErr: false,
+			config: defaultConfig([]configGroupFeed{
+				{Target: nil, Feed: Feed{
+					Name: "Foo",
+					Url:  "whatever",
+					Options: Options{
+						MinFreq:    i(2),
+						InclImages: nil,
+					},
+				}},
+				{Target: s("bla"), Feed: Feed{
+					Name: "Shrubbery",
+					Url:  "google.de",
+					Options: Options{
+						MinFreq:    nil,
+						InclImages: b(false),
+					},
+				}},
+			}, nil),
+		},
+		{name: "Empty Group",
+			inp: `
+feeds:
+   - group: Foo
+     target: bla
+`,
+			wantErr: false,
+			config:  defaultConfig([]configGroupFeed{{Target: s("bla"), Group: group{"Foo", nil}}}, nil),
+		},
+		{name: "Feeds and Groups",
+			inp: `
+feeds:
+   - name: Foo
+     url: whatever
+   - group: G1
+     target: target
+     feeds:
+      - group: G2
+        target: ""
+        feeds: 
+         - name: F1
+           url: google.de
+      - name: F2
+      - group: G3
+`,
+			wantErr: false,
+			config: defaultConfig([]configGroupFeed{
+				{Target: nil, Feed: Feed{
+					Name: "Foo",
+					Url:  "whatever",
+				}},
+				{Target: s("target"), Group: group{
+					Group: "G1",
+					Feeds: []configGroupFeed{
+						{Target: s(""), Group: group{
+							Group: "G2",
+							Feeds: []configGroupFeed{
+								{Target: nil, Feed: Feed{Name: "F1", Url: "google.de"}},
+							}},
+						},
+						{Target: nil, Feed: Feed{Name: "F2"}},
+						{Target: nil, Group: group{Group: "G3"}},
+					}},
+				},
+			}, nil),
+		},
+	}
+
+	for _, tt := range tests {
+		tst.Run(tt.name, func(tst *testing.T) {
+			var buf = []byte(tt.inp)
+			got, err := unmarshal(buf, WithDefault())
+			if (err != nil) != tt.wantErr {
+				tst.Errorf("parse() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if err == nil && !reflect.DeepEqual(got, tt.config) {
+				tst.Errorf("parse() got: %s\nwant: %s", spew.Sdump(got), spew.Sdump(tt.config))
+			}
+		})
+	}
+}
diff --git a/pkg/log/log.go b/pkg/log/log.go
new file mode 100644
index 0000000..0238c7e
--- /dev/null
+++ b/pkg/log/log.go
@@ -0,0 +1,47 @@
+package log
+
+import (
+	"fmt"
+	"log"
+	"os"
+)
+
+var debugLogger = log.New(os.Stdout, "", log.LstdFlags)
+var errorLogger = log.New(os.Stderr, "ERROR ", log.LstdFlags|log.Lmsgprefix)
+var warnLogger = log.New(os.Stdout, "WARN ", log.LstdFlags|log.Lmsgprefix)
+var enableDebug = false
+
+func SetDebug(state bool) {
+	enableDebug = state
+}
+
+func Print(v ...interface{}) {
+	if enableDebug {
+		_ = debugLogger.Output(2, fmt.Sprint(v...))
+	}
+}
+
+func Printf(format string, v ...interface{}) {
+	if enableDebug {
+		_ = debugLogger.Output(2, fmt.Sprintf(format, v...))
+	}
+}
+
+func Error(v ...interface{}) {
+	_ = errorLogger.Output(2, fmt.Sprint(v...))
+}
+
+//noinspection GoUnusedExportedFunction
+func Errorf(format string, a ...interface{}) {
+	_ = errorLogger.Output(2, fmt.Sprintf(format, a...))
+}
+
+//noinspection GoUnusedExportedFunction
+func Warn(v ...interface{}) {
+	_ = warnLogger.Output(2, fmt.Sprint(v...))
+}
+
+//noinspection GoUnusedExportedFunction
+func Warnf(format string, a ...interface{}) {
+	_ = warnLogger.Output(2, fmt.Sprintf(format, a...))
+}
diff --git a/pkg/util/util.go b/pkg/util/util.go
new file mode 100644
index 0000000..c5472ab
--- /dev/null
+++ b/pkg/util/util.go
@@ -0,0 +1,11 @@
+package util
+
+func StrContains(haystack []string, needle string) bool {
+	for _, s := range haystack {
+		if s == needle {
+			return true
+		}
+	}
+
+	return false
+}