diff options
Diffstat (limited to 'vendor/github.com/hashicorp/terraform/terraform/eval.go')
-rw-r--r-- | vendor/github.com/hashicorp/terraform/terraform/eval.go | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/vendor/github.com/hashicorp/terraform/terraform/eval.go b/vendor/github.com/hashicorp/terraform/terraform/eval.go new file mode 100644 index 0000000..3cb088a --- /dev/null +++ b/vendor/github.com/hashicorp/terraform/terraform/eval.go | |||
@@ -0,0 +1,63 @@ | |||
1 | package terraform | ||
2 | |||
3 | import ( | ||
4 | "log" | ||
5 | "strings" | ||
6 | ) | ||
7 | |||
8 | // EvalNode is the interface that must be implemented by graph nodes to | ||
9 | // evaluate/execute. | ||
10 | type EvalNode interface { | ||
11 | // Eval evaluates this node with the given context. The second parameter | ||
12 | // are the argument values. These will match in order and 1-1 with the | ||
13 | // results of the Args() return value. | ||
14 | Eval(EvalContext) (interface{}, error) | ||
15 | } | ||
16 | |||
17 | // GraphNodeEvalable is the interface that graph nodes must implement | ||
18 | // to enable valuation. | ||
19 | type GraphNodeEvalable interface { | ||
20 | EvalTree() EvalNode | ||
21 | } | ||
22 | |||
23 | // EvalEarlyExitError is a special error return value that can be returned | ||
24 | // by eval nodes that does an early exit. | ||
25 | type EvalEarlyExitError struct{} | ||
26 | |||
27 | func (EvalEarlyExitError) Error() string { return "early exit" } | ||
28 | |||
29 | // Eval evaluates the given EvalNode with the given context, properly | ||
30 | // evaluating all args in the correct order. | ||
31 | func Eval(n EvalNode, ctx EvalContext) (interface{}, error) { | ||
32 | // Call the lower level eval which doesn't understand early exit, | ||
33 | // and if we early exit, it isn't an error. | ||
34 | result, err := EvalRaw(n, ctx) | ||
35 | if err != nil { | ||
36 | if _, ok := err.(EvalEarlyExitError); ok { | ||
37 | return nil, nil | ||
38 | } | ||
39 | } | ||
40 | |||
41 | return result, err | ||
42 | } | ||
43 | |||
44 | // EvalRaw is like Eval except that it returns all errors, even if they | ||
45 | // signal something normal such as EvalEarlyExitError. | ||
46 | func EvalRaw(n EvalNode, ctx EvalContext) (interface{}, error) { | ||
47 | path := "unknown" | ||
48 | if ctx != nil { | ||
49 | path = strings.Join(ctx.Path(), ".") | ||
50 | } | ||
51 | |||
52 | log.Printf("[DEBUG] %s: eval: %T", path, n) | ||
53 | output, err := n.Eval(ctx) | ||
54 | if err != nil { | ||
55 | if _, ok := err.(EvalEarlyExitError); ok { | ||
56 | log.Printf("[DEBUG] %s: eval: %T, err: %s", path, n, err) | ||
57 | } else { | ||
58 | log.Printf("[ERROR] %s: eval: %T, err: %s", path, n, err) | ||
59 | } | ||
60 | } | ||
61 | |||
62 | return output, err | ||
63 | } | ||