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-rw-r--r--vendor/github.com/garyburd/redigo/redis/script.go86
1 files changed, 86 insertions, 0 deletions
diff --git a/vendor/github.com/garyburd/redigo/redis/script.go b/vendor/github.com/garyburd/redigo/redis/script.go
new file mode 100644
index 000000000..78605a90a
--- /dev/null
+++ b/vendor/github.com/garyburd/redigo/redis/script.go
@@ -0,0 +1,86 @@
+// Copyright 2012 Gary Burd
+//
+// Licensed under the Apache License, Version 2.0 (the "License"): you may
+// not use this file except in compliance with the License. You may obtain
+// a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+// License for the specific language governing permissions and limitations
+// under the License.
+
+package redis
+
+import (
+ "crypto/sha1"
+ "encoding/hex"
+ "io"
+ "strings"
+)
+
+// Script encapsulates the source, hash and key count for a Lua script. See
+// http://redis.io/commands/eval for information on scripts in Redis.
+type Script struct {
+ keyCount int
+ src string
+ hash string
+}
+
+// NewScript returns a new script object. If keyCount is greater than or equal
+// to zero, then the count is automatically inserted in the EVAL command
+// argument list. If keyCount is less than zero, then the application supplies
+// the count as the first value in the keysAndArgs argument to the Do, Send and
+// SendHash methods.
+func NewScript(keyCount int, src string) *Script {
+ h := sha1.New()
+ io.WriteString(h, src)
+ return &Script{keyCount, src, hex.EncodeToString(h.Sum(nil))}
+}
+
+func (s *Script) args(spec string, keysAndArgs []interface{}) []interface{} {
+ var args []interface{}
+ if s.keyCount < 0 {
+ args = make([]interface{}, 1+len(keysAndArgs))
+ args[0] = spec
+ copy(args[1:], keysAndArgs)
+ } else {
+ args = make([]interface{}, 2+len(keysAndArgs))
+ args[0] = spec
+ args[1] = s.keyCount
+ copy(args[2:], keysAndArgs)
+ }
+ return args
+}
+
+// Do evaluates the script. Under the covers, Do optimistically evaluates the
+// script using the EVALSHA command. If the command fails because the script is
+// not loaded, then Do evaluates the script using the EVAL command (thus
+// causing the script to load).
+func (s *Script) Do(c Conn, keysAndArgs ...interface{}) (interface{}, error) {
+ v, err := c.Do("EVALSHA", s.args(s.hash, keysAndArgs)...)
+ if e, ok := err.(Error); ok && strings.HasPrefix(string(e), "NOSCRIPT ") {
+ v, err = c.Do("EVAL", s.args(s.src, keysAndArgs)...)
+ }
+ return v, err
+}
+
+// SendHash evaluates the script without waiting for the reply. The script is
+// evaluated with the EVALSHA command. The application must ensure that the
+// script is loaded by a previous call to Send, Do or Load methods.
+func (s *Script) SendHash(c Conn, keysAndArgs ...interface{}) error {
+ return c.Send("EVALSHA", s.args(s.hash, keysAndArgs)...)
+}
+
+// Send evaluates the script without waiting for the reply.
+func (s *Script) Send(c Conn, keysAndArgs ...interface{}) error {
+ return c.Send("EVAL", s.args(s.src, keysAndArgs)...)
+}
+
+// Load loads the script without evaluating it.
+func (s *Script) Load(c Conn) error {
+ _, err := c.Do("SCRIPT", "LOAD", s.src)
+ return err
+}