diff options
author | WeidiDeng <weidi_deng@icloud.com> | 2023-02-17 08:08:36 +0800 |
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committer | GitHub <noreply@github.com> | 2023-02-16 17:08:36 -0700 |
commit | 8bc05e598da0068358a2876c45f92f2c77455341 (patch) | |
tree | 4110cd23fd0ddd0374bb909c1c4c53e0c9692176 /caddyconfig/caddyfile/importargs.go | |
parent | bf54892a73373637901c13e018b20cfac15878b4 (diff) |
caddyfile: Implement variadics for import args placeholders (#5249)
* implement variadic placeholders
imported snippets reflect actual lines in file
* add import directive line number for imported snippets
add tests for parsing
* add realfile field to help debug import cycle detection.
* use file field to reflect import chain
* Switch syntax, deprecate old syntax, refactoring
- Moved the import args handling to a separate file
- Using {args[0:1]} syntax now
- Deprecate {args.*} syntax
- Use a replacer map for better control over the parsing
- Add plenty of warnings when invalid placeholders are detected
- Renaming variables, cleanup comments for readability
- More tests to cover edgecases I could think of
- Minor cleanup to snippet tracking in tokens, drop a redundant boolean field in tokens
---------
Co-authored-by: Francis Lavoie <lavofr@gmail.com>
Diffstat (limited to 'caddyconfig/caddyfile/importargs.go')
-rw-r--r-- | caddyconfig/caddyfile/importargs.go | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/caddyconfig/caddyfile/importargs.go b/caddyconfig/caddyfile/importargs.go new file mode 100644 index 0000000..53725a1 --- /dev/null +++ b/caddyconfig/caddyfile/importargs.go @@ -0,0 +1,142 @@ +// Copyright 2015 Matthew Holt and The Caddy 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 caddyfile + +import ( + "regexp" + "strconv" + "strings" + + "github.com/caddyserver/caddy/v2" + "go.uber.org/zap" +) + +// parseVariadic determines if the token is a variadic placeholder, +// and if so, determines the index range (start/end) of args to use. +// Returns a boolean signaling whether a variadic placeholder was found, +// and the start and end indices. +func parseVariadic(token Token, argCount int) (bool, int, int) { + if !strings.HasPrefix(token.Text, "{args[") { + return false, 0, 0 + } + if !strings.HasSuffix(token.Text, "]}") { + return false, 0, 0 + } + + argRange := strings.TrimSuffix(strings.TrimPrefix(token.Text, "{args["), "]}") + if argRange == "" { + caddy.Log().Named("caddyfile").Warn( + "Placeholder "+token.Text+" cannot have an empty index", + zap.String("file", token.File+":"+strconv.Itoa(token.Line))) + return false, 0, 0 + } + + start, end, found := strings.Cut(argRange, ":") + + // If no ":" delimiter is found, this is not a variadic. + // The replacer will pick this up. + if !found { + return false, 0, 0 + } + + var ( + startIndex = 0 + endIndex = argCount + err error + ) + if start != "" { + startIndex, err = strconv.Atoi(start) + if err != nil { + caddy.Log().Named("caddyfile").Warn( + "Variadic placeholder "+token.Text+" has an invalid start index", + zap.String("file", token.File+":"+strconv.Itoa(token.Line))) + return false, 0, 0 + } + } + if end != "" { + endIndex, err = strconv.Atoi(end) + if err != nil { + caddy.Log().Named("caddyfile").Warn( + "Variadic placeholder "+token.Text+" has an invalid end index", + zap.String("file", token.File+":"+strconv.Itoa(token.Line))) + return false, 0, 0 + } + } + + // bound check + if startIndex < 0 || startIndex > endIndex || endIndex > argCount { + caddy.Log().Named("caddyfile").Warn( + "Variadic placeholder "+token.Text+" indices are out of bounds, only "+strconv.Itoa(argCount)+" argument(s) exist", + zap.String("file", token.File+":"+strconv.Itoa(token.Line))) + return false, 0, 0 + } + return true, startIndex, endIndex +} + +// makeArgsReplacer prepares a Replacer which can replace +// non-variadic args placeholders in imported tokens. +func makeArgsReplacer(args []string) *caddy.Replacer { + repl := caddy.NewEmptyReplacer() + repl.Map(func(key string) (any, bool) { + // TODO: Remove the deprecated {args.*} placeholder + // support at some point in the future + if matches := argsRegexpIndexDeprecated.FindStringSubmatch(key); len(matches) > 0 { + value, err := strconv.Atoi(matches[1]) + if err != nil { + caddy.Log().Named("caddyfile").Warn( + "Placeholder {args." + matches[1] + "} has an invalid index") + return nil, false + } + if value >= len(args) { + caddy.Log().Named("caddyfile").Warn( + "Placeholder {args." + matches[1] + "} index is out of bounds, only " + strconv.Itoa(len(args)) + " argument(s) exist") + return nil, false + } + caddy.Log().Named("caddyfile").Warn( + "Placeholder {args." + matches[1] + "} deprecated, use {args[" + matches[1] + "]} instead") + return args[value], true + } + + // Handle args[*] form + if matches := argsRegexpIndex.FindStringSubmatch(key); len(matches) > 0 { + if strings.Contains(matches[1], ":") { + caddy.Log().Named("caddyfile").Warn( + "Variadic placeholder {args[" + matches[1] + "]} must be a token on its own") + return nil, false + } + value, err := strconv.Atoi(matches[1]) + if err != nil { + caddy.Log().Named("caddyfile").Warn( + "Placeholder {args[" + matches[1] + "]} has an invalid index") + return nil, false + } + if value >= len(args) { + caddy.Log().Named("caddyfile").Warn( + "Placeholder {args[" + matches[1] + "]} index is out of bounds, only " + strconv.Itoa(len(args)) + " argument(s) exist") + return nil, false + } + return args[value], true + } + + // Not an args placeholder, ignore + return nil, false + }) + return repl +} + +var ( + argsRegexpIndexDeprecated = regexp.MustCompile(`args\.(.+)`) + argsRegexpIndex = regexp.MustCompile(`args\[(.+)]`) +) |