docs: generate docs for bake standard library functions

Signed-off-by: CrazyMax <1951866+crazy-max@users.noreply.github.com>
This commit is contained in:
CrazyMax
2025-07-02 23:57:02 +02:00
parent 9a5cbaca15
commit 6997d61998
5 changed files with 231 additions and 12 deletions
+5
View File
@@ -132,6 +132,7 @@ var stdlibFunctions = []funcDef{
// value in a list.
func indexOfFunc() function.Function {
return function.New(&function.Spec{
Description: `Finds the element index for a given value in a list.`,
Params: []function.Parameter{
{
Name: "list",
@@ -177,6 +178,7 @@ func indexOfFunc() function.Function {
// basenameFunc constructs a function that returns the last element of a path.
func basenameFunc() function.Function {
return function.New(&function.Spec{
Description: `Returns the last element of a path.`,
Params: []function.Parameter{
{
Name: "path",
@@ -194,6 +196,7 @@ func basenameFunc() function.Function {
// dirnameFunc constructs a function that returns the directory of a path.
func dirnameFunc() function.Function {
return function.New(&function.Spec{
Description: `Returns the directory of a path.`,
Params: []function.Parameter{
{
Name: "path",
@@ -212,6 +215,7 @@ func dirnameFunc() function.Function {
// leaving only characters that are valid for a Bake target name.
func sanitizeFunc() function.Function {
return function.New(&function.Spec{
Description: `Replaces all non-alphanumeric characters with a underscore, leaving only characters that are valid for a Bake target name.`,
Params: []function.Parameter{
{
Name: "name",
@@ -240,6 +244,7 @@ func sanitizeFunc() function.Function {
// This function was imported from terraform's datetime utilities.
func timestampFunc() function.Function {
return function.New(&function.Spec{
Description: `Returns a string representation of the current date and time.`,
Params: []function.Parameter{},
Type: function.StaticReturnType(cty.String),
Impl: func(args []cty.Value, retType cty.Type) (cty.Value, error) {
+2 -3
View File
@@ -1399,8 +1399,7 @@ $ docker buildx bake
## Function
A [set of general-purpose functions][bake_stdlib]
provided by [go-cty][go-cty]
A [set of general-purpose functions][bake_stdlib] provided by [go-cty][go-cty]
are available for use in HCL files:
```hcl
@@ -1440,7 +1439,7 @@ target "webapp-dev" {
[add-host]: https://docs.docker.com/reference/cli/docker/buildx/build/#add-host
[attestations]: https://docs.docker.com/build/attestations/
[bake_stdlib]: https://github.com/docker/buildx/blob/master/bake/hclparser/stdlib.go
[bake_stdlib]: https://github.com/docker/buildx/blob/master/docs/bake-stdlib.md
[build-arg]: https://docs.docker.com/reference/cli/docker/image/build/#build-arg
[build-context]: https://docs.docker.com/reference/cli/docker/buildx/build/#build-context
[cache-backends]: https://docs.docker.com/build/cache/backends/
+128
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@@ -0,0 +1,128 @@
---
title: Bake standard library functions
---
<!---MARKER_STDLIB_START-->
| Name | Description |
|:-------------------------|:-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `absolute` | If the given number is negative then returns its positive equivalent, or otherwise returns the given number unchanged. |
| [`add`](#add) | Returns the sum of the two given numbers. |
| `and` | Applies the logical AND operation to the given boolean values. |
| `base64decode` | |
| `base64encode` | |
| `basename` | Returns the last element of a path. |
| `bcrypt` | |
| `byteslen` | Returns the total number of bytes in the given buffer. |
| `bytesslice` | Extracts a subslice from the given buffer. |
| `can` | |
| `ceil` | Returns the smallest whole number that is greater than or equal to the given value. |
| `chomp` | Removes one or more newline characters from the end of the given string. |
| `chunklist` | Splits a single list into multiple lists where each has at most the given number of elements. |
| `cidrhost` | |
| `cidrnetmask` | |
| `cidrsubnet` | |
| `cidrsubnets` | |
| `coalesce` | Returns the first of the given arguments that isn't null, or raises an error if there are no non-null arguments. |
| `coalescelist` | Returns the first of the given sequences that has a length greater than zero. |
| `compact` | Removes all empty string elements from the given list of strings. |
| `concat` | Concatenates together all of the given lists or tuples into a single sequence, preserving the input order. |
| `contains` | Returns true if the given value is a value in the given list, tuple, or set, or false otherwise. |
| `convert` | |
| `csvdecode` | Parses the given string as Comma Separated Values (as defined by RFC 4180) and returns a map of objects representing the table of data, using the first row as a header row to define the object attributes. |
| `dirname` | Returns the directory of a path. |
| `distinct` | Removes any duplicate values from the given list, preserving the order of remaining elements. |
| `divide` | Divides the first given number by the second. |
| `element` | Returns the element with the given index from the given list or tuple, applying the modulo operation to the given index if it's greater than the number of elements. |
| `equal` | Returns true if the two given values are equal, or false otherwise. |
| `flatten` | Transforms a list, set, or tuple value into a tuple by replacing any given elements that are themselves sequences with a flattened tuple of all of the nested elements concatenated together. |
| `floor` | Returns the greatest whole number that is less than or equal to the given value. |
| `format` | Constructs a string by applying formatting verbs to a series of arguments, using a similar syntax to the C function \"printf\". |
| `formatdate` | Formats a timestamp given in RFC 3339 syntax into another timestamp in some other machine-oriented time syntax, as described in the format string. |
| `formatlist` | Constructs a list of strings by applying formatting verbs to a series of arguments, using a similar syntax to the C function \"printf\". |
| `greaterthan` | Returns true if and only if the second number is greater than the first. |
| `greaterthanorequalto` | Returns true if and only if the second number is greater than or equal to the first. |
| `hasindex` | Returns true if if the given collection can be indexed with the given key without producing an error, or false otherwise. |
| `indent` | Adds a given number of spaces after each newline character in the given string. |
| `index` | Returns the element with the given key from the given collection, or raises an error if there is no such element. |
| `indexof` | Finds the element index for a given value in a list. |
| `int` | Discards any fractional portion of the given number. |
| `join` | Concatenates together the elements of all given lists with a delimiter, producing a single string. |
| `jsondecode` | Parses the given string as JSON and returns a value corresponding to what the JSON document describes. |
| `jsonencode` | Returns a string containing a JSON representation of the given value. |
| `keys` | Returns a list of the keys of the given map in lexicographical order. |
| `length` | Returns the number of elements in the given collection. |
| `lessthan` | Returns true if and only if the second number is less than the first. |
| `lessthanorequalto` | Returns true if and only if the second number is less than or equal to the first. |
| `log` | Returns the logarithm of the given number in the given base. |
| `lookup` | Returns the value of the element with the given key from the given map, or returns the default value if there is no such element. |
| `lower` | Returns the given string with all Unicode letters translated to their lowercase equivalents. |
| `max` | Returns the numerically greatest of all of the given numbers. |
| `md5` | |
| `merge` | Merges all of the elements from the given maps into a single map, or the attributes from given objects into a single object. |
| `min` | Returns the numerically smallest of all of the given numbers. |
| `modulo` | Divides the first given number by the second and then returns the remainder. |
| `multiply` | Returns the product of the two given numbers. |
| `negate` | Multiplies the given number by -1. |
| `not` | Applies the logical NOT operation to the given boolean value. |
| `notequal` | Returns false if the two given values are equal, or true otherwise. |
| `or` | Applies the logical OR operation to the given boolean values. |
| `parseint` | Parses the given string as a number of the given base, or raises an error if the string contains invalid characters. |
| `pow` | Returns the given number raised to the given power (exponentiation). |
| `range` | Returns a list of numbers spread evenly over a particular range. |
| `regex` | Applies the given regular expression pattern to the given string and returns information about a single match, or raises an error if there is no match. |
| `regex_replace` | Applies the given regular expression pattern to the given string and replaces all matches with the given replacement string. |
| `regexall` | Applies the given regular expression pattern to the given string and returns a list of information about all non-overlapping matches, or an empty list if there are no matches. |
| `replace` | Replaces all instances of the given substring in the given string with the given replacement string. |
| `reverse` | Returns the given string with all of its Unicode characters in reverse order. |
| `reverselist` | Returns the given list with its elements in reverse order. |
| `rsadecrypt` | |
| `sanitize` | Replaces all non-alphanumeric characters with a underscore, leaving only characters that are valid for a Bake target name. |
| `sethaselement` | Returns true if the given set contains the given element, or false otherwise. |
| `setintersection` | Returns the intersection of all given sets. |
| `setproduct` | Calculates the cartesian product of two or more sets. |
| `setsubtract` | Returns the relative complement of the two given sets. |
| `setsymmetricdifference` | Returns the symmetric difference of the two given sets. |
| `setunion` | Returns the union of all given sets. |
| `sha1` | |
| `sha256` | |
| `sha512` | |
| `signum` | Returns 0 if the given number is zero, 1 if the given number is positive, or -1 if the given number is negative. |
| `slice` | Extracts a subslice of the given list or tuple value. |
| `sort` | Applies a lexicographic sort to the elements of the given list. |
| `split` | Produces a list of one or more strings by splitting the given string at all instances of a given separator substring. |
| `strlen` | Returns the number of Unicode characters (technically: grapheme clusters) in the given string. |
| `substr` | Extracts a substring from the given string. |
| `subtract` | Returns the difference between the two given numbers. |
| `timeadd` | Adds the duration represented by the given duration string to the given RFC 3339 timestamp string, returning another RFC 3339 timestamp. |
| `timestamp` | Returns a string representation of the current date and time. |
| `title` | Replaces one letter after each non-letter and non-digit character with its uppercase equivalent. |
| `trim` | Removes consecutive sequences of characters in "cutset" from the start and end of the given string. |
| `trimprefix` | Removes the given prefix from the start of the given string, if present. |
| `trimspace` | Removes any consecutive space characters (as defined by Unicode) from the start and end of the given string. |
| `trimsuffix` | Removes the given suffix from the start of the given string, if present. |
| `try` | |
| `upper` | Returns the given string with all Unicode letters translated to their uppercase equivalents. |
| `urlencode` | |
| `uuidv4` | |
| `uuidv5` | |
| `values` | Returns the values of elements of a given map, or the values of attributes of a given object, in lexicographic order by key or attribute name. |
| `zipmap` | Constructs a map from a list of keys and a corresponding list of values, which must both be of the same length. |
<!---MARKER_STDLIB_END-->
## Examples
### <a name="add"></a> `add`
```hcl
# docker-bake.hcl
target "webapp-dev" {
dockerfile = "Dockerfile.webapp"
tags = ["docker.io/username/webapp:latest"]
args = {
buildno = "${add(123, 1)}"
}
}
```
+87
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@@ -1,10 +1,15 @@
package main
import (
"fmt"
"log"
"os"
"regexp"
"sort"
"strings"
"text/tabwriter"
"github.com/docker/buildx/bake/hclparser"
"github.com/docker/buildx/commands"
clidocstool "github.com/docker/cli-docs-tool"
"github.com/docker/cli/cli/command"
@@ -21,9 +26,13 @@ import (
)
const defaultSourcePath = "docs/reference/"
const defaultBakeStdlibSourcePath = "docs/bake-stdlib.md"
var adjustSep = regexp.MustCompile(`\|:---(\s+)`)
type options struct {
source string
bakeSource string
formats []string
}
@@ -79,6 +88,9 @@ func gen(opts *options) error {
if err = c.GenMarkdownTree(cmd); err != nil {
return err
}
if err = generateBakeStdlibDocs(opts.bakeSource); err != nil {
return errors.Wrap(err, "generating bake stdlib docs")
}
case "yaml":
// fix up is needed only for yaml (used for generating docs.docker.com contents)
fixUpExperimentalCLI(cmd)
@@ -97,6 +109,7 @@ func run() error {
opts := &options{}
flags := pflag.NewFlagSet(os.Args[0], pflag.ContinueOnError)
flags.StringVar(&opts.source, "source", defaultSourcePath, "Docs source folder")
flags.StringVar(&opts.bakeSource, "bake-stdlib-source", defaultBakeStdlibSourcePath, "Bake stdlib source file")
flags.StringSliceVar(&opts.formats, "formats", []string{}, "Format (md, yaml)")
if err := flags.Parse(os.Args[1:]); err != nil {
return err
@@ -113,3 +126,77 @@ func main() {
os.Exit(1)
}
}
func generateBakeStdlibDocs(filename string) error {
log.Printf("INFO: Generating Markdown for %q", filename)
dt, err := os.ReadFile(filename)
if err != nil {
return err
}
currentContent := string(dt)
start := strings.Index(currentContent, "<!---MARKER_STDLIB_START-->")
end := strings.Index(currentContent, "<!---MARKER_STDLIB_END-->")
if start == -1 {
return errors.Errorf("no start marker in %s", filename)
}
if end == -1 {
return errors.Errorf("no end marker in %s", filename)
}
table := newMdTable("Name", "Description")
names := make([]string, 0, len(hclparser.Stdlib()))
for name := range hclparser.Stdlib() {
names = append(names, name)
}
sort.Strings(names)
for _, name := range names {
fn := hclparser.Stdlib()[name]
fname := fmt.Sprintf("`%s`", name)
if strings.Contains(currentContent, "<a name=\""+name+"\"></a>") {
fname = fmt.Sprintf("[`%s`](#%s)", name, name)
}
table.AddRow(fname, fn.Description())
}
newContent := currentContent[:start] + "<!---MARKER_STDLIB_START-->\n\n" + table.String() + "\n" + currentContent[end:]
return os.WriteFile(filename, []byte(newContent), 0644)
}
type mdTable struct {
out *strings.Builder
tabWriter *tabwriter.Writer
}
func newMdTable(headers ...string) *mdTable {
w := &strings.Builder{}
t := &mdTable{
out: w,
tabWriter: tabwriter.NewWriter(w, 5, 5, 1, ' ', tabwriter.Debug),
}
t.addHeader(headers...)
return t
}
func (t *mdTable) addHeader(cols ...string) {
t.AddRow(cols...)
_, _ = t.tabWriter.Write([]byte("|" + strings.Repeat(":---\t", len(cols)) + "\n"))
}
func (t *mdTable) AddRow(cols ...string) {
for i := range cols {
cols[i] = mdEscapePipe(cols[i])
}
_, _ = t.tabWriter.Write([]byte("| " + strings.Join(cols, "\t ") + "\t\n"))
}
func (t *mdTable) String() string {
_ = t.tabWriter.Flush()
return adjustSep.ReplaceAllStringFunc(t.out.String()+"\n", func(in string) string {
return strings.ReplaceAll(in, " ", "-")
})
}
func mdEscapePipe(s string) string {
return strings.ReplaceAll(s, `|`, `\|`)
}
+5 -5
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@@ -21,9 +21,9 @@ RUN --mount=target=/context \
--mount=target=.,type=tmpfs <<EOT
set -e
rsync -a /context/. .
docsgen --formats "$FORMATS" --source "docs/reference"
docsgen --formats "$FORMATS" --source "docs/reference" --bake-stdlib-source "docs/bake-stdlib.md"
mkdir /out
cp -r docs/reference /out
cp -r docs/reference docs/bake-stdlib.md /out
rm -f /out/reference/*__INTERNAL_SERVE.yaml /out/reference/*__INTERNAL_SERVE.md
EOT
@@ -36,11 +36,11 @@ RUN --mount=target=/context \
set -e
rsync -a /context/. .
git add -A
rm -rf docs/reference/*
rm -rf docs/reference/* docs/bake-stdlib.md
cp -rf /out/* ./docs/
if [ -n "$(git status --porcelain -- docs/reference)" ]; then
if [ -n "$(git status --porcelain -- docs/reference docs/bake-stdlib.md)" ]; then
echo >&2 'ERROR: Docs result differs. Please update with "make docs"'
git status --porcelain -- docs/reference
git status --porcelain -- docs/reference docs/bake-stdlib.md
exit 1
fi
EOT