Initial commit

vendor/github.com/hyperhq/hypercli/daemon/links/links.go

@@ -0,0 +1,141 @@
+package links
+
+import (
+	"fmt"
+	"path"
+	"strings"
+
+	"github.com/docker/go-connections/nat"
+)
+
+// Link struct holds informations about parent/child linked container
+type Link struct {
+	// Parent container IP address
+	ParentIP string
+	// Child container IP address
+	ChildIP string
+	// Link name
+	Name string
+	// Child environments variables
+	ChildEnvironment []string
+	// Child exposed ports
+	Ports []nat.Port
+}
+
+// NewLink initializes a new Link struct with the provided options.
+func NewLink(parentIP, childIP, name string, env []string, exposedPorts map[nat.Port]struct{}) *Link {
+	var (
+		i     int
+		ports = make([]nat.Port, len(exposedPorts))
+	)
+
+	for p := range exposedPorts {
+		ports[i] = p
+		i++
+	}
+
+	return &Link{
+		Name:             name,
+		ChildIP:          childIP,
+		ParentIP:         parentIP,
+		ChildEnvironment: env,
+		Ports:            ports,
+	}
+}
+
+// ToEnv creates a string's slice containing child container informations in
+// the form of environment variables which will be later exported on container
+// startup.
+func (l *Link) ToEnv() []string {
+	env := []string{}
+
+	_, n := path.Split(l.Name)
+	alias := strings.Replace(strings.ToUpper(n), "-", "_", -1)
+
+	if p := l.getDefaultPort(); p != nil {
+		env = append(env, fmt.Sprintf("%s_PORT=%s://%s:%s", alias, p.Proto(), l.ChildIP, p.Port()))
+	}
+
+	//sort the ports so that we can bulk the continuous ports together
+	nat.Sort(l.Ports, func(ip, jp nat.Port) bool {
+		// If the two ports have the same number, tcp takes priority
+		// Sort in desc order
+		return ip.Int() < jp.Int() || (ip.Int() == jp.Int() && strings.ToLower(ip.Proto()) == "tcp")
+	})
+
+	for i := 0; i < len(l.Ports); {
+		p := l.Ports[i]
+		j := nextContiguous(l.Ports, p.Int(), i)
+		if j > i+1 {
+			env = append(env, fmt.Sprintf("%s_PORT_%s_%s_START=%s://%s:%s", alias, p.Port(), strings.ToUpper(p.Proto()), p.Proto(), l.ChildIP, p.Port()))
+			env = append(env, fmt.Sprintf("%s_PORT_%s_%s_ADDR=%s", alias, p.Port(), strings.ToUpper(p.Proto()), l.ChildIP))
+			env = append(env, fmt.Sprintf("%s_PORT_%s_%s_PROTO=%s", alias, p.Port(), strings.ToUpper(p.Proto()), p.Proto()))
+			env = append(env, fmt.Sprintf("%s_PORT_%s_%s_PORT_START=%s", alias, p.Port(), strings.ToUpper(p.Proto()), p.Port()))
+
+			q := l.Ports[j]
+			env = append(env, fmt.Sprintf("%s_PORT_%s_%s_END=%s://%s:%s", alias, p.Port(), strings.ToUpper(q.Proto()), q.Proto(), l.ChildIP, q.Port()))
+			env = append(env, fmt.Sprintf("%s_PORT_%s_%s_PORT_END=%s", alias, p.Port(), strings.ToUpper(q.Proto()), q.Port()))
+
+			i = j + 1
+			continue
+		} else {
+			i++
+		}
+	}
+	for _, p := range l.Ports {
+		env = append(env, fmt.Sprintf("%s_PORT_%s_%s=%s://%s:%s", alias, p.Port(), strings.ToUpper(p.Proto()), p.Proto(), l.ChildIP, p.Port()))
+		env = append(env, fmt.Sprintf("%s_PORT_%s_%s_ADDR=%s", alias, p.Port(), strings.ToUpper(p.Proto()), l.ChildIP))
+		env = append(env, fmt.Sprintf("%s_PORT_%s_%s_PORT=%s", alias, p.Port(), strings.ToUpper(p.Proto()), p.Port()))
+		env = append(env, fmt.Sprintf("%s_PORT_%s_%s_PROTO=%s", alias, p.Port(), strings.ToUpper(p.Proto()), p.Proto()))
+	}
+
+	// Load the linked container's name into the environment
+	env = append(env, fmt.Sprintf("%s_NAME=%s", alias, l.Name))
+
+	if l.ChildEnvironment != nil {
+		for _, v := range l.ChildEnvironment {
+			parts := strings.SplitN(v, "=", 2)
+			if len(parts) < 2 {
+				continue
+			}
+			// Ignore a few variables that are added during docker build (and not really relevant to linked containers)
+			if parts[0] == "HOME" || parts[0] == "PATH" {
+				continue
+			}
+			env = append(env, fmt.Sprintf("%s_ENV_%s=%s", alias, parts[0], parts[1]))
+		}
+	}
+	return env
+}
+
+func nextContiguous(ports []nat.Port, value int, index int) int {
+	if index+1 == len(ports) {
+		return index
+	}
+	for i := index + 1; i < len(ports); i++ {
+		if ports[i].Int() > value+1 {
+			return i - 1
+		}
+
+		value++
+	}
+	return len(ports) - 1
+}
+
+// Default port rules
+func (l *Link) getDefaultPort() *nat.Port {
+	var p nat.Port
+	i := len(l.Ports)
+
+	if i == 0 {
+		return nil
+	} else if i > 1 {
+		nat.Sort(l.Ports, func(ip, jp nat.Port) bool {
+			// If the two ports have the same number, tcp takes priority
+			// Sort in desc order
+			return ip.Int() < jp.Int() || (ip.Int() == jp.Int() && strings.ToLower(ip.Proto()) == "tcp")
+		})
+	}
+	p = l.Ports[0]
+	return &p
+}