Vendor integration dependencies.

integration/vendor/github.com/docker/libcompose/config/interpolation.go

@@ -0,0 +1,169 @@
+package config
+
+import (
+	"bytes"
+	"fmt"
+	"strings"
+
+	"github.com/Sirupsen/logrus"
+)
+
+func isNum(c uint8) bool {
+	return c >= '0' && c <= '9'
+}
+
+func validVariableNameChar(c uint8) bool {
+	return c == '_' ||
+		c >= 'A' && c <= 'Z' ||
+		c >= 'a' && c <= 'z' ||
+		isNum(c)
+}
+
+func parseVariable(line string, pos int, mapping func(string) string) (string, int, bool) {
+	var buffer bytes.Buffer
+
+	for ; pos < len(line); pos++ {
+		c := line[pos]
+
+		switch {
+		case validVariableNameChar(c):
+			buffer.WriteByte(c)
+		default:
+			return mapping(buffer.String()), pos - 1, true
+		}
+	}
+
+	return mapping(buffer.String()), pos, true
+}
+
+func parseVariableWithBraces(line string, pos int, mapping func(string) string) (string, int, bool) {
+	var buffer bytes.Buffer
+
+	for ; pos < len(line); pos++ {
+		c := line[pos]
+
+		switch {
+		case c == '}':
+			bufferString := buffer.String()
+
+			if bufferString == "" {
+				return "", 0, false
+			}
+
+			return mapping(buffer.String()), pos, true
+		case validVariableNameChar(c):
+			buffer.WriteByte(c)
+		default:
+			return "", 0, false
+		}
+	}
+
+	return "", 0, false
+}
+
+func parseInterpolationExpression(line string, pos int, mapping func(string) string) (string, int, bool) {
+	c := line[pos]
+
+	switch {
+	case c == '$':
+		return "$", pos, true
+	case c == '{':
+		return parseVariableWithBraces(line, pos+1, mapping)
+	case !isNum(c) && validVariableNameChar(c):
+		// Variables can't start with a number
+		return parseVariable(line, pos, mapping)
+	default:
+		return "", 0, false
+	}
+}
+
+func parseLine(line string, mapping func(string) string) (string, bool) {
+	var buffer bytes.Buffer
+
+	for pos := 0; pos < len(line); pos++ {
+		c := line[pos]
+		switch {
+		case c == '$':
+			var replaced string
+			var success bool
+
+			replaced, pos, success = parseInterpolationExpression(line, pos+1, mapping)
+
+			if !success {
+				return "", false
+			}
+
+			buffer.WriteString(replaced)
+		default:
+			buffer.WriteByte(c)
+		}
+	}
+
+	return buffer.String(), true
+}
+
+func parseConfig(option, service string, data *interface{}, mapping func(string) string) error {
+	switch typedData := (*data).(type) {
+	case string:
+		var success bool
+
+		*data, success = parseLine(typedData, mapping)
+
+		if !success {
+			return fmt.Errorf("Invalid interpolation format for \"%s\" option in service \"%s\": \"%s\"", option, service, typedData)
+		}
+	case []interface{}:
+		for k, v := range typedData {
+			err := parseConfig(option, service, &v, mapping)
+
+			if err != nil {
+				return err
+			}
+
+			typedData[k] = v
+		}
+	case map[interface{}]interface{}:
+		for k, v := range typedData {
+			err := parseConfig(option, service, &v, mapping)
+
+			if err != nil {
+				return err
+			}
+
+			typedData[k] = v
+		}
+	}
+
+	return nil
+}
+
+// Interpolate replaces variables in the raw map representation of the project file
+func Interpolate(environmentLookup EnvironmentLookup, config *RawServiceMap) error {
+	for k, v := range *config {
+		for k2, v2 := range v {
+			err := parseConfig(k2, k, &v2, func(s string) string {
+				values := environmentLookup.Lookup(s, k, nil)
+
+				if len(values) == 0 {
+					logrus.Warnf("The %s variable is not set. Substituting a blank string.", s)
+					return ""
+				}
+
+				// Use first result if many are given
+				value := values[0]
+
+				// Environment variables come in key=value format
+				// Return everything past first '='
+				return strings.SplitN(value, "=", 2)[1]
+			})
+
+			if err != nil {
+				return err
+			}
+
+			(*config)[k][k2] = v2
+		}
+	}
+
+	return nil
+}