Add more packages: crypto, config, data/db, validation (#11)

**What**

- Added `crypto` for encryption helpers
- Added `config` package with common config section implementations
- Added `data/db` that contains all kinds of utils working with db and
its types
- Added `validation` with common validation rules
- Improved `testing` adding bytes helper
- Move `pkg/data/db` to `pkg/db`
- Fix floppy test

Author: rdner

go.mod

@@ -1,8 +1,12 @@
 module github.com/contiamo/go-base
 
 require (
+	github.com/Masterminds/squirrel v1.1.0
+	github.com/asaskevich/govalidator v0.0.0-20190424111038-f61b66f89f4a // indirect
 	github.com/bakins/net-http-recover v0.0.0-20141007104922-6cba69d01459
+	github.com/cenkalti/backoff v2.2.1+incompatible
 	github.com/codahale/hdrhistogram v0.0.0-20161010025455-3a0bb77429bd // indirect
+	github.com/dgrijalva/jwt-go v3.2.0+incompatible
 	github.com/go-chi/chi v4.0.2+incompatible
 	github.com/go-ozzo/ozzo-validation v3.6.0+incompatible
 	github.com/golang/protobuf v1.3.2
@@ -16,6 +20,7 @@ require (
 	github.com/opentracing/opentracing-go v1.1.0
 	github.com/pkg/errors v0.8.1
 	github.com/prometheus/client_golang v1.1.0
+	github.com/robfig/cron v1.2.0
 	github.com/rs/cors v1.7.0
 	github.com/satori/go.uuid v1.2.0
 	github.com/sirupsen/logrus v1.4.2

go.sum

@@ -1,19 +1,27 @@
 cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
+github.com/Masterminds/squirrel v1.1.0 h1:baP1qLdoQCeTw3ifCdOq2dkYc6vGcmRdaociKLbEJXs=
+github.com/Masterminds/squirrel v1.1.0/go.mod h1:yaPeOnPG5ZRwL9oKdTsO/prlkPbXWZlRVMQ/gGlzIuA=
 github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
 github.com/alecthomas/units v0.0.0-20151022065526-2efee857e7cf/go.mod h1:ybxpYRFXyAe+OPACYpWeL0wqObRcbAqCMya13uyzqw0=
+github.com/asaskevich/govalidator v0.0.0-20190424111038-f61b66f89f4a h1:idn718Q4B6AGu/h5Sxe66HYVdqdGu2l9Iebqhi/AEoA=
+github.com/asaskevich/govalidator v0.0.0-20190424111038-f61b66f89f4a/go.mod h1:lB+ZfQJz7igIIfQNfa7Ml4HSf2uFQQRzpGGRXenZAgY=
 github.com/bakins/net-http-recover v0.0.0-20141007104922-6cba69d01459 h1:EoeZjn5IKppnD1q/+SXExqb0DxBVEQMBHTVpHFZN258=
 github.com/bakins/net-http-recover v0.0.0-20141007104922-6cba69d01459/go.mod h1:QpFZUHntFabd1Oro3/Exapv58wgWN3Sej2NbOVYg/1E=
 github.com/beorn7/perks v0.0.0-20180321164747-3a771d992973/go.mod h1:Dwedo/Wpr24TaqPxmxbtue+5NUziq4I4S80YR8gNf3Q=
 github.com/beorn7/perks v1.0.0/go.mod h1:KWe93zE9D1o94FZ5RNwFwVgaQK1VOXiVxmqh+CedLV8=
 github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
 github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=
+github.com/cenkalti/backoff v2.2.1+incompatible h1:tNowT99t7UNflLxfYYSlKYsBpXdEet03Pg2g16Swow4=
+github.com/cenkalti/backoff v2.2.1+incompatible/go.mod h1:90ReRw6GdpyfrHakVjL/QHaoyV4aDUVVkXQJJJ3NXXM=
 github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
 github.com/codahale/hdrhistogram v0.0.0-20161010025455-3a0bb77429bd h1:qMd81Ts1T2OTKmB4acZcyKaMtRnY5Y44NuXGX2GFJ1w=
 github.com/codahale/hdrhistogram v0.0.0-20161010025455-3a0bb77429bd/go.mod h1:sE/e/2PUdi/liOCUjSTXgM1o87ZssimdTWN964YiIeI=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/dgrijalva/jwt-go v3.2.0+incompatible h1:7qlOGliEKZXTDg6OTjfoBKDXWrumCAMpl/TFQ4/5kLM=
+github.com/dgrijalva/jwt-go v3.2.0+incompatible/go.mod h1:E3ru+11k8xSBh+hMPgOLZmtrrCbhqsmaPHjLKYnJCaQ=
 github.com/go-chi/chi v4.0.2+incompatible h1:maB6vn6FqCxrpz4FqWdh4+lwpyZIQS7YEAUcHlgXVRs=
 github.com/go-chi/chi v4.0.2+incompatible/go.mod h1:eB3wogJHnLi3x/kFX2A+IbTBlXxmMeXJVKy9tTv1XzQ=
 github.com/go-kit/kit v0.8.0/go.mod h1:xBxKIO96dXMWWy0MnWVtmwkA9/13aqxPnvrjFYMA2as=
@@ -51,6 +59,10 @@ github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORN
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
+github.com/lann/builder v0.0.0-20180802200727-47ae307949d0 h1:SOEGU9fKiNWd/HOJuq6+3iTQz8KNCLtVX6idSoTLdUw=
+github.com/lann/builder v0.0.0-20180802200727-47ae307949d0/go.mod h1:dXGbAdH5GtBTC4WfIxhKZfyBF/HBFgRZSWwZ9g/He9o=
+github.com/lann/ps v0.0.0-20150810152359-62de8c46ede0 h1:P6pPBnrTSX3DEVR4fDembhRWSsG5rVo6hYhAB/ADZrk=
+github.com/lann/ps v0.0.0-20150810152359-62de8c46ede0/go.mod h1:vmVJ0l/dxyfGW6FmdpVm2joNMFikkuWg0EoCKLGUMNw=
 github.com/lib/pq v1.1.1 h1:sJZmqHoEaY7f+NPP8pgLB/WxulyR3fewgCM2qaSlBb4=
 github.com/lib/pq v1.1.1/go.mod h1:5WUZQaWbwv1U+lTReE5YruASi9Al49XbQIvNi/34Woo=
 github.com/matttproud/golang_protobuf_extensions v1.0.1 h1:4hp9jkHxhMHkqkrB3Ix0jegS5sx/RkqARlsWZ6pIwiU=
@@ -83,6 +95,8 @@ github.com/prometheus/procfs v0.0.0-20181005140218-185b4288413d/go.mod h1:c3At6R
 github.com/prometheus/procfs v0.0.2/go.mod h1:TjEm7ze935MbeOT/UhFTIMYKhuLP4wbCsTZCD3I8kEA=
 github.com/prometheus/procfs v0.0.3 h1:CTwfnzjQ+8dS6MhHHu4YswVAD99sL2wjPqP+VkURmKE=
 github.com/prometheus/procfs v0.0.3/go.mod h1:4A/X28fw3Fc593LaREMrKMqOKvUAntwMDaekg4FpcdQ=
+github.com/robfig/cron v1.2.0 h1:ZjScXvvxeQ63Dbyxy76Fj3AT3Ut0aKsyd2/tl3DTMuQ=
+github.com/robfig/cron v1.2.0/go.mod h1:JGuDeoQd7Z6yL4zQhZ3OPEVHB7fL6Ka6skscFHfmt2k=
 github.com/rs/cors v1.7.0 h1:+88SsELBHx5r+hZ8TCkggzSstaWNbDvThkVK8H6f9ik=
 github.com/rs/cors v1.7.0/go.mod h1:gFx+x8UowdsKA9AchylcLynDq+nNFfI8FkUZdN/jGCU=
 github.com/satori/go.uuid v1.2.0 h1:0uYX9dsZ2yD7q2RtLRtPSdGDWzjeM3TbMJP9utgA0ww=

pkg/config/authorization.go

@@ -0,0 +1,8 @@
+package config
+
+// Authorization contains all the authorization-related parameters
+type Authorization struct {
+	// HeaderName is the name of the header where the authorization middleware is supposed
+	// to be looking for a JWT token
+	HeaderName string `json:"headerName"`
+}

pkg/config/database.go

@@ -0,0 +1,95 @@
+package config
+
+import (
+	"fmt"
+	"io/ioutil"
+	"strings"
+
+	"github.com/pkg/errors"
+)
+
+var defaultPorts = map[string]uint32{
+	"postgres": 5432,
+}
+
+// Database contains all the configuration parameters for a database
+type Database struct {
+	// Host of the database server
+	Host string `json:"host"`
+	// Port of the database server, if empty, we will attempt to parse the port from the host value,
+	// if Host does not have a port value, then we will use the default value from the db driver
+	Port uint32 `json:"port"`
+	// Name is the name of the database on the host
+	Name string `json:"name"`
+	// Username to access the database
+	Username string `json:"username"`
+	// PasswordPath is a path to the file where the password is stored
+	PasswordPath string `json:"passwordPath"`
+	// PoolSize is the max number of concurrent connections to the database,
+	// <=0 is unlimited
+	PoolSize int `json:"poolSize"`
+	// DriverName is the database driver name e.g. postgres
+	DriverName string `json:"driverName"`
+}
+
+// GetPassword gets the database password from PasswordPath
+func (cfg *Database) GetPassword() (string, error) {
+	if cfg.PasswordPath == "" {
+		return "", nil
+	}
+	passwordBytes, err := ioutil.ReadFile(cfg.PasswordPath)
+	if err != nil {
+		return "", errors.Wrapf(err, "can not read the database password file `%s`", cfg.PasswordPath)
+	}
+
+	return strings.TrimSpace(string(passwordBytes)), nil
+}
+
+// GetHost returns the host name of the underlying db
+func (cfg *Database) GetHost() string {
+	if cfg.Host != "" {
+		return cfg.Host
+	}
+
+	return "localhost"
+}
+
+// GetPort returns the port of the underlying db
+func (cfg *Database) GetPort() uint32 {
+	if cfg.Port != 0 {
+		return cfg.Port
+	}
+
+	return defaultPorts[cfg.DriverName]
+}
+
+// GetConnectionString returns the formed connection string
+func (cfg *Database) GetConnectionString() (connStr string, err error) {
+	connStr = "sslmode=disable "
+
+	if cfg.Host != "" {
+		connStr += fmt.Sprintf("host=%v ", cfg.Host)
+	}
+
+	if cfg.Port != 0 {
+		connStr += fmt.Sprintf("port=%d ", cfg.Port)
+	}
+
+	if cfg.Name != "" {
+		connStr += fmt.Sprintf("dbname=%v ", cfg.Name)
+	}
+	if cfg.Username != "" {
+		connStr += fmt.Sprintf("user=%v ", cfg.Username)
+	}
+	if cfg.PasswordPath != "" {
+		pw, err := cfg.GetPassword()
+		if err != nil {
+			return "", err
+		}
+		if pw != "" {
+			connStr += fmt.Sprintf("password=%v ", pw)
+		}
+	}
+
+	return strings.TrimSpace(connStr), nil
+}

pkg/config/database_test.go

@@ -0,0 +1,153 @@
+package config
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestDatabaseGetPassword(t *testing.T) {
+	t.Run("Returns the password when it's found", func(t *testing.T) {
+		cfg := Database{PasswordPath: "./testdata/password"}
+		password, err := cfg.GetPassword()
+		require.NoError(t, err)
+		require.Equal(t, "password", password)
+	})
+	t.Run("Returns no password when it's not set", func(t *testing.T) {
+		cfg := Database{}
+		password, err := cfg.GetPassword()
+		require.NoError(t, err)
+		require.Empty(t, password)
+	})
+
+	t.Run("Returns the error when the password is not found", func(t *testing.T) {
+		cfg := Database{PasswordPath: "./testdata/invalid"}
+		password, err := cfg.GetPassword()
+		require.Error(t, err)
+		require.Empty(t, password)
+		require.Equal(t, "can not read the database password file `./testdata/invalid`: open ./testdata/invalid: no such file or directory", err.Error())
+	})
+}
+
+func TestDatabaseGetHost(t *testing.T) {
+	t.Run("Returns the host name when specified", func(t *testing.T) {
+		host := "some.host"
+		cfg := Database{Host: host}
+		require.Equal(t, host, cfg.GetHost())
+	})
+	t.Run("Returns `localhost` when name is not specified", func(t *testing.T) {
+		cfg := Database{}
+		require.Equal(t, "localhost", cfg.GetHost())
+	})
+}
+
+func TestDatabaseGetPort(t *testing.T) {
+	t.Run("Returns specified port when it's set", func(t *testing.T) {
+		var port uint32 = 80
+		cfg := Database{Port: port}
+		require.Equal(t, port, cfg.GetPort())
+	})
+	t.Run("Returns default port when it's not set", func(t *testing.T) {
+		cfg := Database{DriverName: "postgres"}
+		require.Equal(t, uint32(5432), cfg.GetPort())
+	})
+	t.Run("Returns 0 when the port is not set and the default value is not found", func(t *testing.T) {
+		cfg := Database{}
+		require.Equal(t, uint32(0), cfg.GetPort())
+	})
+}
+
+func TestDatabaseGetConnectionString(t *testing.T) {
+	cases := []struct {
+		name     string
+		cfg      Database
+		expected string
+		err      string
+	}{
+		{
+			name: "Returns the full connection string when all is set",
+			cfg: Database{
+				Host:         "example.com",
+				Port:         80,
+				Name:         "database",
+				Username:     "root",
+				PasswordPath: "./testdata/password",
+			},
+			expected: "sslmode=disable host=example.com port=80 dbname=database user=root password=password",
+		},
+		{
+			name: "Returns a connection string when Host is not set",
+			cfg: Database{
+				Port:         80,
+				Name:         "database",
+				Username:     "root",
+				PasswordPath: "./testdata/password",
+			},
+			expected: "sslmode=disable port=80 dbname=database user=root password=password",
+		},
+		{
+			name: "Returns a connection string when Port is not set",
+			cfg: Database{
+				Host:         "example.com",
+				Name:         "database",
+				Username:     "root",
+				PasswordPath: "./testdata/password",
+			},
+			expected: "sslmode=disable host=example.com dbname=database user=root password=password",
+		},
+		{
+			name: "Returns a connection string when Name is not set",
+			cfg: Database{
+				Host:         "example.com",
+				Port:         80,
+				Username:     "root",
+				PasswordPath: "./testdata/password",
+			},
+			expected: "sslmode=disable host=example.com port=80 user=root password=password",
+		},
+		{
+			name: "Returns a connection string when Username is not set",
+			cfg: Database{
+				Host:         "example.com",
+				Name:         "database",
+				Port:         80,
+				PasswordPath: "./testdata/password",
+			},
+			expected: "sslmode=disable host=example.com port=80 dbname=database password=password",
+		},
+		{
+			name: "Returns a connection string when PasswordPath is not set",
+			cfg: Database{
+				Host:     "example.com",
+				Name:     "database",
+				Port:     80,
+				Username: "root",
+			},
+			expected: "sslmode=disable host=example.com port=80 dbname=database user=root",
+		},
+		{
+			name: "Returns an error when PasswordPath is wrong",
+			cfg: Database{
+				Host:         "example.com",
+				Name:         "database",
+				Port:         80,
+				Username:     "root",
+				PasswordPath: "./testdata/invalid",
+			},
+			err: "can not read the database password file `./testdata/invalid`: open ./testdata/invalid: no such file or directory",
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			str, err := tc.cfg.GetConnectionString()
+			if tc.err != "" {
+				require.Error(t, err)
+				require.Equal(t, tc.err, err.Error())
+				return
+			}
+			require.NoError(t, err)
+			require.Equal(t, tc.expected, str)
+		})
+	}
+}

pkg/config/http.go

@@ -0,0 +1,7 @@
+package config
+
+// HTTP contains all configuration parameters for HTTP
+type HTTP struct {
+	// Address to listen for the HTTP server
+	Address string `json:"address"`
+}

pkg/config/jwt.go

@@ -0,0 +1,29 @@
+package config
+
+import (
+	"crypto/rsa"
+	"io/ioutil"
+
+	jwt "github.com/dgrijalva/jwt-go"
+	"github.com/pkg/errors"
+)
+
+// JWT contains all JWT related parameters
+type JWT struct {
+	// PublicKeyPath is a path to the public key for JWT signature verification
+	PublicKeyPath string `json:"publicKeyPath"`
+}
+
+// GetPublicKey gets the encryption key from a given path
+func (j *JWT) GetPublicKey() (publicKey *rsa.PublicKey, err error) {
+	if j.PublicKeyPath == "" {
+		return nil, errors.New("path to the public key file is empty")
+	}
+
+	keyBytes, err := ioutil.ReadFile(j.PublicKeyPath)
+	if err != nil {
+		return nil, errors.Wrapf(err, "can not read the public key file `%s`", j.PublicKeyPath)
+	}
+
+	return jwt.ParseRSAPublicKeyFromPEM(keyBytes)
+}