crossplane
Reliable and fast NGINX configuration file parser and builder
Install
You can install both the Command Line Interface and Python Module via:
pip install crossplane
Command Line Interface
usage: crossplane <command> [options]
various operations for nginx config files
optional arguments:
-h, --help show this help message and exit
-V, --version show program's version number and exit
commands:
parse parses a json payload for an nginx config
build builds an nginx config from a json payload
lex lexes tokens from an nginx config file
minify removes all whitespace from an nginx config
format formats an nginx config file
help show help for commands
crossplane parse
This command will take a path to a main NGINX config file as input, then parse the entire config into the schema defined below, and dumps the entire thing as a JSON payload.
usage: crossplane parse [-h] [-o OUT] [-i NUM] [--ignore DIRECTIVES]
[--no-catch] [--tb-onerror] [--single-file]
[--include-comments] [--strict]
filename
parses a json payload for an nginx config
positional arguments:
filename the nginx config file
optional arguments:
-h, --help show this help message and exit
-o OUT, --out OUT write output to a file
-i NUM, --indent NUM number of spaces to indent output
--ignore DIRECTIVES ignore directives (comma-separated)
--no-catch only collect first error in file
--tb-onerror include tracebacks in config errors
--combine use includes to create one single file
--single-file do not include other config files
--include-comments include comments in json
--strict raise errors for unknown directives
Privacy and Security
Since crossplane is usually used to create payloads that are sent to
different servers, it's important to keep security in mind. For that
reason, the --ignore option was added. It can be used to keep certain
sensitive directives out of the payload output entirely.
For example, we always use the equivalent of this flag in the NGINX Amplify Agent out of respect for our users' privacy:
--ignore=auth_basic_user_file,secure_link_secret,ssl_certificate_key,ssl_client_certificate,ssl_password_file,ssl_stapling_file,ssl_trusted_certificate
Schema
Response Object
{
"status": String, // "ok" or "failed" if "errors" is not empty
"errors": Array, // aggregation of "errors" from Config objects
"config": Array // Array of Config objects
}Config Object
{
"file": String, // the full path of the config file
"status": String, // "ok" or "failed" if errors is not empty array
"errors": Array, // Array of Error objects
"parsed": Array // Array of Directive objects
}Directive Object
{
"directive": String, // the name of the directive
"line": Number, // integer line number the directive started on
"args": Array, // Array of String arguments
"includes": Array, // Array of integers (included iff this is an include directive)
"block": Array // Array of Directive Objects (included iff this is a block)
}Note
If this is an include directive and the --single-file flag was not
used, an "includes" value will be used that holds an Array of indices
of the configs that are included by this directive.
If this is a block directive, a "block" value will be used that holds
an Array of more Directive Objects that define the block context.
Error Object
{
"file": String, // the full path of the config file
"line": Number, // integer line number the directive that caused the error
"error": String, // the error message
"callback": Object // only included iff an "onerror" function was passed to parse()
}Note
If the --tb-onerror flag was used by crossplane parse, "callback"
will contain a string that represents the traceback that the error
caused.
Example
The main NGINX config file is at /etc/nginx/nginx.conf:
events {
worker_connections 1024;
}
http {
include conf.d/*.conf;
}And this config file is at /etc/nginx/conf.d/servers.conf:
server {
listen 8080;
location / {
try_files 'foo bar' baz;
}
}
server {
listen 8081;
location / {
return 200 'success!';
}
}So then if you run this:
crossplane parse --indent=4 /etc/nginx/nginx.conf
The prettified JSON output would look like this:
{
"status": "ok",
"errors": [],
"config": [
{
"file": "/etc/nginx/nginx.conf",
"status": "ok",
"errors": [],
"parsed": [
{
"directive": "events",
"line": 1,
"args": [],
"block": [
{
"directive": "worker_connections",
"line": 2,
"args": [
"1024"
]
}
]
},
{
"directive": "http",
"line": 5,
"args": [],
"block": [
{
"directive": "include",
"line": 6,
"args": [
"conf.d/*.conf"
],
"includes": [
1
]
}
]
}
]
},
{
"file": "/etc/nginx/conf.d/servers.conf",
"status": "ok",
"errors": [],
"parsed": [
{
"directive": "server",
"line": 1,
"args": [],
"block": [
{
"directive": "listen",
"line": 2,
"args": [
"8080"
]
},
{
"directive": "location",
"line": 3,
"args": [
"/"
],
"block": [
{
"directive": "try_files",
"line": 4,
"args": [
"foo bar",
"baz"
]
}
]
}
]
},
{
"directive": "server",
"line": 8,
"args": [],
"block": [
{
"directive": "listen",
"line": 9,
"args": [
"8081"
]
},
{
"directive": "location",
"line": 10,
"args": [
"/"
],
"block": [
{
"directive": "return",
"line": 11,
"args": [
"200",
"success!"
]
}
]
}
]
}
]
}
]
}crossplane parse (advanced)
This tool uses two flags that can change how crossplane handles
errors.
The first, --no-catch, can be used if you'd prefer that crossplane
quit parsing after the first error it finds.
The second, --tb-onerror, will add a "callback" key to all error
objects in the JSON output, each containing a string representation of
the traceback that would have been raised by the parser if the exception
had not been caught. This can be useful for logging purposes.
crossplane build
This command will take a path to a file as input. The file should
contain a JSON representation of an NGINX config that has the structure
defined above. Saving and using the output from crossplane parse to
rebuild your config files should not cause any differences in content
except for the formatting.
usage: crossplane build [-h] [-d PATH] [-f] [-i NUM | -t] [--no-headers]
[--stdout] [-v]
filename
builds an nginx config from a json payload
positional arguments:
filename the file with the config payload
optional arguments:
-h, --help show this help message and exit
-v, --verbose verbose output
-d PATH, --dir PATH the base directory to build in
-f, --force overwrite existing files
-i NUM, --indent NUM number of spaces to indent output
-t, --tabs indent with tabs instead of spaces
--no-headers do not write header to configs
--stdout write configs to stdout instead
crossplane lex
This command takes an NGINX config file, splits it into tokens by removing whitespace and comments, and dumps the list of tokens as a JSON array.
usage: crossplane lex [-h] [-o OUT] [-i NUM] [-n] filename
lexes tokens from an nginx config file
positional arguments:
filename the nginx config file
optional arguments:
-h, --help show this help message and exit
-o OUT, --out OUT write output to a file
-i NUM, --indent NUM number of spaces to indent output
-n, --line-numbers include line numbers in json payload
Example
Passing in this NGINX config file at /etc/nginx/nginx.conf:
events {
worker_connections 1024;
}
http {
include conf.d/*.conf;
}By running:
crossplane lex /etc/nginx/nginx.conf
Will result in this JSON output:
["events","{","worker_connections","1024",";","}","http","{","include","conf.d/*.conf",";","}"]However, if you decide to use the --line-numbers flag, your output
will look
like:
[["events",1],["{",1],["worker_connections",2],["1024",2],[";",2],["}",3],["http",5],["{",5],["include",6],["conf.d/*.conf",6],[";",6],["}",7]]crossplane format
This is a quick and dirty tool that uses crossplane
parse internally to format an NGINX config file.
It serves the purpose of demonstrating what you can do with crossplane's
parsing abilities. It is not meant to be a fully fleshed out, feature-rich
formatting tool. If that is what you are looking for, then you may want to
look writing your own using crossplane's Python API.
usage: crossplane format [-h] [-o OUT] [-i NUM | -t] filename
formats an nginx config file
positional arguments:
filename the nginx config file
optional arguments:
-h, --help show this help message and exit
-o OUT, --out OUT write output to a file
-i NUM, --indent NUM number of spaces to indent output
-t, --tabs indent with tabs instead of spaces
crossplane minify
This is a simple and fun little tool that uses crossplane
lex internally to remove as much whitespace from an
NGINX config file as possible without affecting what it does. It can't
imagine it will have much of a use to most people, but it demonstrates
the kinds of things you can do with crossplane's lexing abilities.
usage: crossplane minify [-h] [-o OUT] filename
removes all whitespace from an nginx config
positional arguments:
filename the nginx config file
optional arguments:
-h, --help show this help message and exit
-o OUT, --out OUT write output to a file
Python Module
In addition to the command line tool, you can import crossplane as a
python module. There are two basic functions that the module will
provide you: parse and lex.
crossplane.parse()
import crossplane
payload = crossplane.parse('/etc/nginx/nginx.conf')This will return the same payload as described in the crossplane parse section, except it will be Python dicts and not one giant JSON string.
crossplane.build()
import crossplane
config = crossplane.build(
[{
"directive": "events",
"args": [],
"block": [{
"directive": "worker_connections",
"args": ["1024"]
}]
}]
)This will return a single string that contains an entire NGINX config file.
crossplane.lex()
import crossplane
tokens = crossplane.lex('/etc/nginx/nginx.conf')crossplane.lex generates 2-tuples. Inserting these pairs into a list
will result in a long list similar to what you can see in the
crossplane lex section when the --line-numbers flag
is used, except it will obviously be a Python list of tuples and not one
giant JSON string.
Other Languages
- Go port by @aluttik: https://github.com/aluttik/go-crossplane
- Ruby port by @gdanko: https://github.com/gdanko/crossplane