mirror of
https://github.com/mbierlee/mirage-config.git
synced 2024-11-15 04:44:01 +01:00
630 lines
18 KiB
D
630 lines
18 KiB
D
/**
|
|
* Base utilities for working with configurations.
|
|
*
|
|
* Authors:
|
|
* Mike Bierlee, m.bierlee@lostmoment.com
|
|
* Copyright: 2022 Mike Bierlee
|
|
* License:
|
|
* This software is licensed under the terms of the MIT license.
|
|
* The full terms of the license can be found in the LICENSE file.
|
|
*/
|
|
|
|
module mirage.config;
|
|
|
|
import std.exception : enforce;
|
|
import std.string : split, startsWith, endsWith, join, lastIndexOf, strip, toLower;
|
|
import std.conv : to, ConvException;
|
|
import std.file : readText;
|
|
import std.path : extension;
|
|
|
|
import mirage.json : loadJsonConfig;
|
|
|
|
/**
|
|
* Used by the ConfigDictionary when something goes wrong when reading configuration.
|
|
*/
|
|
class ConfigReadException : Exception {
|
|
this(string msg, string file = __FILE__, size_t line = __LINE__) {
|
|
super(msg, file, line);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Used by ConfigFactory instances when loading or parsing configuration fails.
|
|
*/
|
|
class ConfigCreationException : Exception {
|
|
this(string msg, string file = __FILE__, size_t line = __LINE__) {
|
|
super(msg, file, line);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Used by ConfigDictionary when there is something wrong with the path when calling ConfigDictionary.get()
|
|
*/
|
|
class PathParseException : Exception {
|
|
this(string msg, string path, string file = __FILE__, size_t line = __LINE__) {
|
|
string fullMsg = msg ~ " (Path: " ~ path ~ ")";
|
|
super(fullMsg, file, line);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* The configuration tree is made up of specific types of ConfigNodes.
|
|
* Used as generic type for ConfigFactory and ConfigDictionary.
|
|
*/
|
|
interface ConfigNode {
|
|
string nodeType();
|
|
}
|
|
|
|
/**
|
|
* A configuration item that is any sort of primitive value (strings, numbers or null).
|
|
*/
|
|
class ValueNode : ConfigNode {
|
|
string value;
|
|
|
|
this() {
|
|
}
|
|
|
|
this(string value) {
|
|
this.value = value;
|
|
}
|
|
|
|
string nodeType() {
|
|
return "value";
|
|
}
|
|
}
|
|
|
|
/**
|
|
* A configuration item that is an object.
|
|
*
|
|
* ObjectNodes contain a node dictionary that points to other ConfigNodes.
|
|
*/
|
|
class ObjectNode : ConfigNode {
|
|
ConfigNode[string] children;
|
|
|
|
this() {
|
|
}
|
|
|
|
this(ConfigNode[string] children) {
|
|
this.children = children;
|
|
}
|
|
|
|
this(string[string] values) {
|
|
foreach (key, value; values) {
|
|
children[key] = new ValueNode(value);
|
|
}
|
|
}
|
|
|
|
string nodeType() {
|
|
return "object";
|
|
}
|
|
}
|
|
|
|
/**
|
|
* A configuration item that is an array.
|
|
*
|
|
* Contains other ConfigNodes as children.
|
|
*/
|
|
class ArrayNode : ConfigNode {
|
|
ConfigNode[] children;
|
|
|
|
this() {
|
|
}
|
|
|
|
this(ConfigNode[] children...) {
|
|
this.children = children;
|
|
}
|
|
|
|
this(string[] values...) {
|
|
foreach (string value; values) {
|
|
children ~= new ValueNode(value);
|
|
}
|
|
}
|
|
|
|
string nodeType() {
|
|
return "array";
|
|
}
|
|
}
|
|
|
|
private interface PathSegment {
|
|
}
|
|
|
|
private class ArrayPathSegment : PathSegment {
|
|
const size_t index;
|
|
|
|
this(const size_t index) {
|
|
this.index = index;
|
|
}
|
|
}
|
|
|
|
private class PropertyPathSegment : PathSegment {
|
|
const string propertyName;
|
|
|
|
this(const string propertyName) {
|
|
this.propertyName = propertyName;
|
|
}
|
|
}
|
|
|
|
private class ConfigPath {
|
|
private const string path;
|
|
private string[] previousSegments;
|
|
private string[] segments;
|
|
|
|
this(const string path) {
|
|
this.path = path;
|
|
segmentAndNormalize(path);
|
|
}
|
|
|
|
private void segmentAndNormalize(string path) {
|
|
foreach (segment; path.split(".")) {
|
|
auto trimmedSegment = segment.strip;
|
|
|
|
if (trimmedSegment.length <= 0) {
|
|
continue;
|
|
}
|
|
|
|
if (trimmedSegment.endsWith("]") && !trimmedSegment.startsWith("[")) {
|
|
auto openBracketPos = trimmedSegment.lastIndexOf("[");
|
|
if (openBracketPos != -1) {
|
|
segments ~= trimmedSegment[0 .. openBracketPos];
|
|
segments ~= trimmedSegment[openBracketPos .. $];
|
|
continue;
|
|
}
|
|
}
|
|
|
|
segments ~= trimmedSegment;
|
|
}
|
|
}
|
|
|
|
PathSegment getNextSegment() {
|
|
if (segments.length == 0) {
|
|
return null;
|
|
}
|
|
|
|
PathSegment ret(PathSegment segment) {
|
|
previousSegments ~= segments[0];
|
|
segments = segments[1 .. $];
|
|
return segment;
|
|
}
|
|
|
|
string segment = segments[0];
|
|
|
|
if (segment.startsWith("[") && segment.endsWith("]")) {
|
|
if (segment.length <= 2) {
|
|
throw new PathParseException("Path has array accessor but no index specified", path);
|
|
}
|
|
|
|
auto indexString = segment[1 .. $ - 1];
|
|
try {
|
|
auto index = indexString.to!size_t;
|
|
return ret(new ArrayPathSegment(index));
|
|
} catch (ConvException e) {
|
|
throw new PathParseException("Value '" ~ indexString ~ "' is not acceptable as an array index", path);
|
|
}
|
|
}
|
|
|
|
return ret(new PropertyPathSegment(segment));
|
|
}
|
|
|
|
string getCurrentPath() {
|
|
return previousSegments.join(".");
|
|
}
|
|
}
|
|
|
|
/**
|
|
* A ConfigDictionary contains the configuration tree and facilities to get values from that tree.
|
|
*/
|
|
class ConfigDictionary {
|
|
ConfigNode rootNode;
|
|
|
|
this() {
|
|
}
|
|
|
|
this(ConfigNode rootNode) {
|
|
this.rootNode = rootNode;
|
|
}
|
|
|
|
/**
|
|
* Get values from the configuration using config path notation.
|
|
*
|
|
* Params:
|
|
* configPath = Path to the wanted config value. The path is separated by dots, e.g. "server.public.hostname".
|
|
* Values from arrays can be selected by brackets, for example: "server[3].hostname.ports[0]".
|
|
* When the config is just a value, for example just a string, it can be fetched by just specifying "." as path.
|
|
* Although the path should be universally the same over all types of config files, some might not lend to this structure,
|
|
* and have a more specific way of retrieving data from the config. See the examples and specific config factories for
|
|
* more details.
|
|
*
|
|
* Returns: The value at the path in the configuration. To convert it use get!T().
|
|
*/
|
|
string get(string configPath) {
|
|
auto path = new ConfigPath(configPath);
|
|
auto node = getNodeAt(path);
|
|
auto value = cast(ValueNode) node;
|
|
if (value) {
|
|
return value.value;
|
|
} else {
|
|
throw new ConfigReadException(
|
|
"Value expected but " ~ node.nodeType ~ " found at path: " ~ createExceptionPath(
|
|
path));
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Get values from the configuration and attempts to convert them to the specified type.
|
|
*
|
|
* Params:
|
|
* configPath = Path to the wanted config value. See get().
|
|
* Returns: The value at the path in the configuration.
|
|
*/
|
|
ConvertToType get(ConvertToType)(string configPath) {
|
|
return get(configPath).to!ConvertToType;
|
|
}
|
|
|
|
/**
|
|
* Fetch a sub-section of the config as another config.
|
|
*
|
|
* Commonly used for example to fetch further configuration from arrays, e.g.: `getConfig("http.servers[3]")`
|
|
* which then returns the rest of the config at that path.
|
|
*
|
|
* Params:
|
|
* configPath = Path to the wanted config. See get().
|
|
* Returns: A sub-section of the configuration.
|
|
*/
|
|
ConfigDictionary getConfig(string configPath) {
|
|
auto path = new ConfigPath(configPath);
|
|
auto node = getNodeAt(path);
|
|
return new ConfigDictionary(node);
|
|
}
|
|
|
|
string createExceptionPath(ConfigPath path) {
|
|
return "'" ~ path.path ~ "' (at '" ~ path.getCurrentPath() ~ "')";
|
|
}
|
|
|
|
private ConfigNode getNodeAt(ConfigPath path) {
|
|
enforce!ConfigReadException(rootNode !is null, "The config is empty");
|
|
|
|
auto currentNode = rootNode;
|
|
PathSegment currentPathSegment = path.getNextSegment();
|
|
|
|
void throwPathNotExists() {
|
|
throw new ConfigReadException("Path does not exist: " ~ createExceptionPath(path));
|
|
}
|
|
|
|
void ifNotNullPointer(void* obj, void delegate() fn) {
|
|
if (obj) {
|
|
fn();
|
|
} else {
|
|
throwPathNotExists();
|
|
}
|
|
}
|
|
|
|
void ifNotNull(Object obj, void delegate() fn) {
|
|
if (obj) {
|
|
fn();
|
|
} else {
|
|
throwPathNotExists();
|
|
}
|
|
}
|
|
|
|
while (currentPathSegment !is null) {
|
|
if (currentNode is null) {
|
|
throwPathNotExists();
|
|
}
|
|
|
|
auto valueNode = cast(ValueNode) currentNode;
|
|
if (valueNode) {
|
|
throwPathNotExists();
|
|
}
|
|
|
|
auto arrayPath = cast(ArrayPathSegment) currentPathSegment;
|
|
if (arrayPath) {
|
|
auto arrayNode = cast(ArrayNode) currentNode;
|
|
ifNotNull(arrayNode, {
|
|
if (arrayNode.children.length < arrayPath.index) {
|
|
throw new ConfigReadException(
|
|
"Array index out of bounds: " ~ createExceptionPath(path));
|
|
}
|
|
|
|
currentNode = arrayNode.children[arrayPath.index];
|
|
});
|
|
}
|
|
|
|
auto propertyPath = cast(PropertyPathSegment) currentPathSegment;
|
|
if (propertyPath) {
|
|
auto objectNode = cast(ObjectNode) currentNode;
|
|
ifNotNull(objectNode, {
|
|
auto propertyNode = propertyPath.propertyName in objectNode.children;
|
|
ifNotNullPointer(propertyNode, {
|
|
currentNode = *propertyNode;
|
|
});
|
|
});
|
|
}
|
|
|
|
currentPathSegment = path.getNextSegment();
|
|
}
|
|
|
|
return currentNode;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* The base class used by configuration factories for specific file types.
|
|
*/
|
|
abstract class ConfigFactory {
|
|
/**
|
|
* Loads a configuration from the specified path from disk.
|
|
*
|
|
* Params:
|
|
* path = Path to file. OS dependent, but UNIX paths are generally working.
|
|
* Returns: The parsed configuration.
|
|
*/
|
|
ConfigDictionary loadFile(string path) {
|
|
auto json = readText(path);
|
|
return parseConfig(json);
|
|
}
|
|
|
|
/**
|
|
* Parse configuration from the given string.
|
|
*
|
|
* Params:
|
|
* contents = Text contents of the config to be parsed.
|
|
* Returns: The parsed configuration.
|
|
*/
|
|
ConfigDictionary parseConfig(string contents);
|
|
}
|
|
|
|
ConfigDictionary loadConfig(const string configPath) {
|
|
auto extension = configPath.extension.toLower;
|
|
if (extension == ".json") {
|
|
return loadJsonConfig(configPath);
|
|
}
|
|
|
|
throw new ConfigCreationException(
|
|
"File extension '" ~ extension ~ "' is not recognized as a supported config file format. Please use a specific function to load it, such as 'loadJsonConfig()'");
|
|
}
|
|
|
|
version (unittest) {
|
|
import std.exception : assertThrown;
|
|
import std.math.operations : isClose;
|
|
|
|
@("Dictionary creation")
|
|
unittest {
|
|
auto root = new ObjectNode([
|
|
"english": new ArrayNode([new ValueNode("one"), new ValueNode("two")]),
|
|
"spanish": new ArrayNode(new ValueNode("uno"), new ValueNode("dos"))
|
|
]);
|
|
|
|
auto config = new ConfigDictionary();
|
|
config.rootNode = root;
|
|
}
|
|
|
|
@("Get value in config with empty root fails")
|
|
unittest {
|
|
auto config = new ConfigDictionary();
|
|
|
|
assertThrown!ConfigReadException(config.get("."));
|
|
}
|
|
|
|
@("Get value in root with empty path")
|
|
unittest {
|
|
auto config = new ConfigDictionary(new ValueNode("hehehe"));
|
|
|
|
assert(config.get("") == "hehehe");
|
|
}
|
|
|
|
@("Get value in root with just a dot")
|
|
unittest {
|
|
auto config = new ConfigDictionary(new ValueNode("yup"));
|
|
|
|
assert(config.get(".") == "yup");
|
|
}
|
|
|
|
@("Get value in root fails when root is not a value")
|
|
unittest {
|
|
auto config = new ConfigDictionary(new ArrayNode());
|
|
|
|
assertThrown!ConfigReadException(config.get("."));
|
|
}
|
|
|
|
@("Get array value from root")
|
|
unittest {
|
|
auto config = new ConfigDictionary(new ArrayNode("aap", "noot", "mies"));
|
|
|
|
assert(config.get("[0]") == "aap");
|
|
assert(config.get("[1]") == "noot");
|
|
assert(config.get("[2]") == "mies");
|
|
}
|
|
|
|
@("Get value from object at root")
|
|
unittest {
|
|
auto config = new ConfigDictionary(new ObjectNode([
|
|
"aap": "monkey",
|
|
"noot": "nut",
|
|
"mies": "mies" // It's a name!
|
|
])
|
|
);
|
|
|
|
assert(config.get("aap") == "monkey");
|
|
assert(config.get("noot") == "nut");
|
|
assert(config.get("mies") == "mies");
|
|
}
|
|
|
|
@("Get value from object in object")
|
|
unittest {
|
|
auto config = new ConfigDictionary(
|
|
new ObjectNode([
|
|
"server": new ObjectNode([
|
|
"port": "8080"
|
|
])
|
|
])
|
|
);
|
|
|
|
assert(config.get("server.port") == "8080");
|
|
}
|
|
|
|
@("Get value from array in object")
|
|
unittest {
|
|
auto config = new ConfigDictionary(
|
|
new ObjectNode([
|
|
"hostname": new ArrayNode(["google.com", "dlang.org"])
|
|
])
|
|
);
|
|
|
|
assert(config.get("hostname.[1]") == "dlang.org");
|
|
}
|
|
|
|
@("Exception is thrown when array out of bounds when fetching from root")
|
|
unittest {
|
|
auto config = new ConfigDictionary(
|
|
new ArrayNode([
|
|
"google.com", "dlang.org"
|
|
])
|
|
);
|
|
|
|
assertThrown!ConfigReadException(config.get("[5]"));
|
|
}
|
|
|
|
@("Exception is thrown when array out of bounds when fetching from object")
|
|
unittest {
|
|
auto config = new ConfigDictionary(
|
|
new ObjectNode([
|
|
"hostname": new ArrayNode(["google.com", "dlang.org"])
|
|
])
|
|
);
|
|
|
|
assertThrown!ConfigReadException(config.get("hostname.[5]"));
|
|
}
|
|
|
|
@("Exception is thrown when path does not exist")
|
|
unittest {
|
|
auto config = new ConfigDictionary(new ObjectNode(
|
|
[
|
|
"hostname": new ObjectNode(["cluster": new ValueNode("")])
|
|
])
|
|
);
|
|
|
|
assertThrown!ConfigReadException(config.get("hostname.cluster.spacey"));
|
|
}
|
|
|
|
@("Exception is thrown when given path terminates too early")
|
|
unittest {
|
|
auto config = new ConfigDictionary(new ObjectNode(
|
|
[
|
|
"hostname": new ObjectNode(["cluster": new ValueNode(null)])
|
|
])
|
|
);
|
|
|
|
assertThrown!ConfigReadException(config.get("hostname"));
|
|
}
|
|
|
|
@("Exception is thrown when given path does not exist because config is an array")
|
|
unittest {
|
|
auto config = new ConfigDictionary(new ArrayNode());
|
|
|
|
assertThrown!ConfigReadException(config.get("hostname"));
|
|
}
|
|
|
|
@("Get value from objects in array")
|
|
unittest {
|
|
auto config = new ConfigDictionary(new ArrayNode(
|
|
new ObjectNode(["wrong": "yes"]),
|
|
new ObjectNode(["wrong": "no"]),
|
|
new ObjectNode(["wrong": "very"]),
|
|
));
|
|
|
|
assert(config.get("[1].wrong") == "no");
|
|
}
|
|
|
|
@("Get value from config with mixed types")
|
|
unittest {
|
|
auto config = new ConfigDictionary(
|
|
new ObjectNode([
|
|
"uno": cast(ConfigNode) new ValueNode("one"),
|
|
"dos": cast(ConfigNode) new ArrayNode(["nope", "two"]),
|
|
"tres": cast(ConfigNode) new ObjectNode(["thisone": "three"])
|
|
])
|
|
);
|
|
|
|
assert(config.get("uno") == "one");
|
|
assert(config.get("dos.[1]") == "two");
|
|
assert(config.get("tres.thisone") == "three");
|
|
}
|
|
|
|
@("Ignore empty segments")
|
|
unittest {
|
|
auto config = new ConfigDictionary(
|
|
new ObjectNode(
|
|
[
|
|
"one": new ObjectNode(["two": new ObjectNode(["three": "four"])])
|
|
])
|
|
);
|
|
|
|
assert(config.get(".one..two...three....") == "four");
|
|
}
|
|
|
|
@("Support conventional array indexing notation")
|
|
unittest {
|
|
auto config = new ConfigDictionary(
|
|
new ObjectNode(
|
|
[
|
|
"one": new ObjectNode([
|
|
"two": new ArrayNode(["dino", "mino"])
|
|
])
|
|
])
|
|
);
|
|
|
|
assert(config.get("one.two[1]") == "mino");
|
|
}
|
|
|
|
@("Get and convert values")
|
|
unittest {
|
|
auto config = new ConfigDictionary(
|
|
new ObjectNode([
|
|
"uno": new ValueNode("1223"),
|
|
"dos": new ValueNode("true"),
|
|
"tres": new ValueNode("Hi you"),
|
|
"quatro": new ValueNode("1.3")
|
|
])
|
|
);
|
|
|
|
assert(config.get!int("uno") == 1223);
|
|
assert(config.get!bool("dos") == true);
|
|
assert(config.get!string("tres") == "Hi you");
|
|
assert(isClose(config.get!float("quatro"), 1.3));
|
|
}
|
|
|
|
@("Get config from array")
|
|
unittest {
|
|
auto configOne = new ConfigDictionary(new ObjectNode(
|
|
[
|
|
"servers": new ArrayNode([
|
|
new ObjectNode(["hostname": "lala.com"]),
|
|
new ObjectNode(["hostname": "lele.com"])
|
|
])
|
|
])
|
|
);
|
|
|
|
auto config = configOne.getConfig("servers[0]");
|
|
assert(config.get("hostname") == "lala.com");
|
|
}
|
|
|
|
@("Trim spaces in path segments")
|
|
unittest {
|
|
auto config = new ConfigDictionary(
|
|
new ObjectNode(["que": new ObjectNode(["pasa hombre": "not much"])])
|
|
);
|
|
|
|
assert(config.get(" que. pasa hombre ") == "not much");
|
|
}
|
|
|
|
@("Load configurations using the loadConfig convenience function")
|
|
unittest {
|
|
auto jsonConfig = loadConfig("testfiles/groot.json");
|
|
|
|
assert(jsonConfig.get("name") == "Groot");
|
|
assert(jsonConfig.get("traits[1]") == "tree");
|
|
assert(jsonConfig.get("age") == "8728");
|
|
assert(jsonConfig.get("taxNumber") == null);
|
|
}
|
|
}
|