summaryrefslogtreecommitdiff
path: root/pkg/bindings/connection.go
blob: 116af9709d6f40027804e4e03a1cc858d35b3c33 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
package bindings

import (
	"context"
	"fmt"
	"io"
	"net"
	"net/http"
	"net/url"
	"path/filepath"
	"strings"

	"github.com/containers/libpod/pkg/api/handlers"
	jsoniter "github.com/json-iterator/go"
	"github.com/pkg/errors"
)

var (
	defaultConnectionPath string = filepath.Join(fmt.Sprintf("v%s", handlers.MinimalApiVersion), "libpod")
)

type APIResponse struct {
	*http.Response
	Request *http.Request
}

type Connection struct {
	scheme  string
	address string
	client  *http.Client
}

// NewConnection takes a URI as a string and returns a context with the
// Connection embedded as a value.  This context needs to be passed to each
// endpoint to work correctly.
//
// A valid URI connection should be scheme://
// For example tcp://localhost:<port>
// or unix://run/podman/podman.sock
func NewConnection(uri string) (context.Context, error) {
	u, err := url.Parse(uri)
	if err != nil {
		return nil, err
	}
	// TODO once ssh is implemented, remove this block and
	// add it to the conditional beneath it
	if u.Scheme == "ssh" {
		return nil, ErrNotImplemented
	}
	if u.Scheme != "tcp" && u.Scheme != "unix" {
		return nil, errors.Errorf("%s is not a support schema", u.Scheme)
	}

	if u.Scheme == "tcp" && !strings.HasPrefix(uri, "tcp://") {
		return nil, errors.New("tcp URIs should begin with tcp://")
	}

	address := u.Path
	if u.Scheme == "tcp" {
		address = u.Host
	}
	newConn := newConnection(u.Scheme, address)
	ctx := context.WithValue(context.Background(), "conn", &newConn)
	if err := pingNewConnection(ctx); err != nil {
		return nil, err
	}
	return ctx, nil
}

// pingNewConnection pings to make sure the RESTFUL service is up
// and running. it should only be used where initializing a connection
func pingNewConnection(ctx context.Context) error {
	conn, err := GetConnectionFromContext(ctx)
	if err != nil {
		return err
	}
	// the ping endpoint sits at / in this case
	response, err := conn.DoRequest(nil, http.MethodGet, "../../../_ping", nil)
	if err != nil {
		return err
	}
	if response.StatusCode == http.StatusOK {
		return nil
	}
	return errors.Errorf("ping response was %q", response.StatusCode)
}

// newConnection takes a scheme and address and creates a connection from it
func newConnection(scheme, address string) Connection {
	client := http.Client{
		Transport: &http.Transport{
			DialContext: func(_ context.Context, _, _ string) (net.Conn, error) {
				return net.Dial(scheme, address)
			},
		},
	}
	newConn := Connection{
		client:  &client,
		address: address,
		scheme:  scheme,
	}
	return newConn
}

func (c *Connection) makeEndpoint(u string) string {
	// The d character in the url is discarded and is meaningless
	return fmt.Sprintf("http://d/%s%s", defaultConnectionPath, u)
}

// DoRequest assembles the http request and returns the response
func (c *Connection) DoRequest(httpBody io.Reader, httpMethod, endpoint string, queryParams map[string]string, pathValues ...string) (*APIResponse, error) {
	var (
		err      error
		response *http.Response
	)
	safePathValues := make([]interface{}, len(pathValues))
	// Make sure path values are http url safe
	for i, pv := range pathValues {
		safePathValues[i] = url.PathEscape(pv)
	}
	// Lets eventually use URL for this which might lead to safer
	// usage
	safeEndpoint := fmt.Sprintf(endpoint, safePathValues...)
	e := c.makeEndpoint(safeEndpoint)
	req, err := http.NewRequest(httpMethod, e, httpBody)
	if err != nil {
		return nil, err
	}
	if len(queryParams) > 0 {
		// if more desirable we could use url to form the encoded endpoint with params
		r := req.URL.Query()
		for k, v := range queryParams {
			r.Add(k, url.QueryEscape(v))
		}
		req.URL.RawQuery = r.Encode()
	}
	// Give the Do three chances in the case of a comm/service hiccup
	for i := 0; i < 3; i++ {
		response, err = c.client.Do(req) // nolint
		if err == nil {
			break
		}
	}
	return &APIResponse{response, req}, err
}

// GetConnectionFromContext returns a bindings connection from the context
// being passed into each method.
func GetConnectionFromContext(ctx context.Context) (*Connection, error) {
	c := ctx.Value("conn")
	if c == nil {
		return nil, errors.New("unable to get connection from context")
	}
	conn := c.(*Connection)
	return conn, nil
}

// FiltersToHTML converts our typical filter format of a
// map[string][]string to a query/html safe string.
func FiltersToHTML(filters map[string][]string) (string, error) {
	lowerCaseKeys := make(map[string][]string)
	for k, v := range filters {
		lowerCaseKeys[strings.ToLower(k)] = v
	}
	unsafeString, err := jsoniter.MarshalToString(lowerCaseKeys)
	if err != nil {
		return "", err
	}
	return url.QueryEscape(unsafeString), nil
}

// IsInformation returns true if the response code is 1xx
func (h *APIResponse) IsInformational() bool {
	return h.Response.StatusCode/100 == 1
}

// IsSuccess returns true if the response code is 2xx
func (h *APIResponse) IsSuccess() bool {
	return h.Response.StatusCode/100 == 2
}

// IsRedirection returns true if the response code is 3xx
func (h *APIResponse) IsRedirection() bool {
	return h.Response.StatusCode/100 == 3
}

// IsClientError returns true if the response code is 4xx
func (h *APIResponse) IsClientError() bool {
	return h.Response.StatusCode/100 == 4
}

// IsServerError returns true if the response code is 5xx
func (h *APIResponse) IsServerError() bool {
	return h.Response.StatusCode/100 == 5
}