forked from digitalocean/go-qemu
/
generate.go
173 lines (161 loc) · 4.08 KB
/
generate.go
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
// Copyright 2016 The go-qemu Authors.
//
// 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 gen
import (
"bytes"
"errors"
"path/filepath"
"reflect"
"strings"
"text/template"
"github.com/fatih/camelcase"
)
// neededTypes returns the subset of API that should be rendered to file.
//
// The subset to render is defined as the transitive closure of all types
// reachable from commands and events.
func neededTypes(api map[name]interface{}) map[name]interface{} {
need := map[name]interface{}{}
for n, i := range api {
switch i.(type) {
case command:
need[n] = i
case event:
need[n] = i
}
}
for {
nextNeed := expandTypes(api, need)
if len(need) == len(nextNeed) {
break
}
need = nextNeed
}
return need
}
// expandTypes returns the union of need and all types it directly references.
func expandTypes(api, need map[name]interface{}) map[name]interface{} {
ret := map[name]interface{}{}
for n, i := range need {
ret[n] = i
switch v := i.(type) {
case command:
addName(api, ret, v.Name)
if v.BoxedInput {
addName(api, ret, v.Inputs.Ref)
} else {
for _, f := range v.Inputs.Fields(api) {
addName(api, ret, f.Type)
}
}
if v.Output.Type != "" {
addName(api, ret, v.Output.Type)
}
case event:
addName(api, ret, v.Name)
if v.BoxedData {
addName(api, ret, v.Data.Ref)
} else {
for _, f := range v.Data.Fields(api) {
addName(api, ret, f.Type)
}
}
case structType:
addName(api, ret, v.Name)
for _, f := range v.Fields {
addName(api, ret, f.Type)
}
if v.Base != "" {
for _, f := range api[v.Base].(structType).Fields {
addName(api, ret, f.Type)
}
}
case simpleUnion:
addName(api, ret, v.Name)
for _, typ := range v.Options {
addName(api, ret, typ)
}
case flatUnion:
addName(api, ret, v.Name)
for _, f := range v.Base.Fields(api) {
addName(api, ret, f.Type)
}
for _, typ := range v.Options {
for _, f := range api[typ].(structType).Fields {
addName(api, ret, f.Type)
}
}
case alternate:
addName(api, ret, v.Name)
for _, typ := range v.Options {
addName(api, ret, typ)
}
case enum:
addName(api, ret, v.Name)
}
}
return ret
}
func addName(api, need map[name]interface{}, name name) {
if name.SimpleType() {
return
}
v, ok := api[name]
if ok {
need[name] = v
}
}
// renderAPI generates the Go implementation for the types listed in need.
func renderAPI(templateDir string, api, need map[name]interface{}) ([]byte, error) {
tmpl := template.New("")
tmpl.Funcs(template.FuncMap{
"API": func() map[name]interface{} { return api },
"typeOf": func(v interface{}) string {
if v == nil {
return "nil"
}
return strings.ToLower(reflect.TypeOf(v).Name())
},
"unexport": func(s string) string {
ws := camelcase.Split(s)
if upperWords[strings.ToLower(ws[0])] {
ws[0] = strings.ToLower(ws[0])
} else {
ws[0] = strings.ToLower(ws[0][:1]) + ws[0][1:]
}
ret := strings.Join(ws, "")
if ret == "type" {
return "typ"
}
return ret
},
"render": func(v interface{}) (string, error) {
n := strings.ToLower(reflect.TypeOf(v).Name())
var b bytes.Buffer
err := tmpl.ExecuteTemplate(&b, n, v)
return b.String(), err
},
"abort": func(s string) (string, error) { return "", errors.New(s) },
"last": func(fs fields, i int) bool { return i == len(fs)-1 },
})
tmpl, err := tmpl.ParseGlob(filepath.Join(templateDir, "*"))
if err != nil {
return nil, err
}
var out bytes.Buffer
if err := tmpl.ExecuteTemplate(&out, "main", need); err != nil {
return nil, err
}
return out.Bytes(), nil
}