use std::fmt; use failure::*; use serde_json::{json, Value}; use url::form_urlencoded; #[derive(Default, Debug, Fail)] pub struct ParameterError { error_list: Vec, } /// Error type for schema validation /// /// The validation functions may produce several error message, /// i.e. when validation objects, it can produce one message for each /// erroneous object property. // fixme: record parameter names, to make it usefull to display errord // on HTML forms. impl ParameterError { pub fn new() -> Self { Self { error_list: Vec::new(), } } pub fn push(&mut self, value: Error) { self.error_list.push(value); } pub fn len(&self) -> usize { self.error_list.len() } pub fn is_empty(&self) -> bool { self.len() == 0 } } impl fmt::Display for ParameterError { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { let mut msg = String::new(); if !self.is_empty() { msg.push_str("parameter verification errors\n\n"); } msg.push_str( &self .error_list .iter() .fold(String::from(""), |acc, item| acc + &item.to_string() + "\n"), ); write!(f, "{}", msg) } } #[derive(Debug)] pub struct BooleanSchema { pub description: &'static str, pub default: Option, } impl BooleanSchema { pub const fn new(description: &'static str) -> Self { BooleanSchema { description, default: None, } } pub const fn default(mut self, default: bool) -> Self { self.default = Some(default); self } pub const fn schema(self) -> Schema { Schema::Boolean(self) } } #[derive(Debug)] pub struct IntegerSchema { pub description: &'static str, pub minimum: Option, pub maximum: Option, pub default: Option, } impl IntegerSchema { pub const fn new(description: &'static str) -> Self { IntegerSchema { description, default: None, minimum: None, maximum: None, } } pub const fn default(mut self, default: isize) -> Self { self.default = Some(default); self } pub const fn minimum(mut self, minimum: isize) -> Self { self.minimum = Some(minimum); self } pub const fn maximum(mut self, maximium: isize) -> Self { self.maximum = Some(maximium); self } pub const fn schema(self) -> Schema { Schema::Integer(self) } fn check_constraints(&self, value: isize) -> Result<(), Error> { if let Some(minimum) = self.minimum { if value < minimum { bail!( "value must have a minimum value of {} (got {})", minimum, value ); } } if let Some(maximum) = self.maximum { if value > maximum { bail!( "value must have a maximum value of {} (got {})", maximum, value ); } } Ok(()) } } /// Helper to represent const regular expressions /// /// This is mostly a workaround, unless we can create const_fn Regex. pub struct ConstRegexPattern { pub regex_string: &'static str, pub regex_obj: fn() -> &'static regex::Regex, } impl std::fmt::Debug for ConstRegexPattern { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { write!(f, "{:?}", self.regex_string) } } /// Macro to generate a ConstRegexPattern #[macro_export] macro_rules! const_regex { () => {}; ($(#[$attr:meta])* pub ($($vis:tt)+) $name:ident = $regex:expr; $($rest:tt)*) => { const_regex! { (pub ($($vis)+)) $(#[$attr])* $name = $regex; $($rest)* } }; ($(#[$attr:meta])* pub $name:ident = $regex:expr; $($rest:tt)*) => { const_regex! { (pub) $(#[$attr])* $name = $regex; $($rest)* } }; ($(#[$attr:meta])* $name:ident = $regex:expr; $($rest:tt)*) => { const_regex! { () $(#[$attr])* $name = $regex; $($rest)* } }; ( ($($pub:tt)*) $(#[$attr:meta])* $name:ident = $regex:expr; $($rest:tt)* ) => { $(#[$attr])* $($pub)* const $name: ConstRegexPattern = ConstRegexPattern { regex_string: $regex, regex_obj: (|| -> &'static regex::Regex { lazy_static::lazy_static! { static ref SCHEMA: regex::Regex = regex::Regex::new($regex).unwrap(); } &SCHEMA }) }; const_regex! { $($rest)* } }; } #[derive(Debug)] pub struct StringSchema { pub description: &'static str, pub default: Option<&'static str>, pub min_length: Option, pub max_length: Option, pub format: Option<&'static ApiStringFormat>, } impl StringSchema { pub const fn new(description: &'static str) -> Self { StringSchema { description, default: None, min_length: None, max_length: None, format: None, } } pub const fn default(mut self, text: &'static str) -> Self { self.default = Some(text); self } pub const fn format(mut self, format: &'static ApiStringFormat) -> Self { self.format = Some(format); self } pub const fn min_length(mut self, min_length: usize) -> Self { self.min_length = Some(min_length); self } pub const fn max_length(mut self, max_length: usize) -> Self { self.max_length = Some(max_length); self } pub const fn schema(self) -> Schema { Schema::String(self) } fn check_length(&self, length: usize) -> Result<(), Error> { if let Some(min_length) = self.min_length { if length < min_length { bail!("value must be at least {} characters long", min_length); } } if let Some(max_length) = self.max_length { if length > max_length { bail!("value may only be {} characters long", max_length); } } Ok(()) } pub fn check_constraints(&self, value: &str) -> Result<(), Error> { self.check_length(value.chars().count())?; if let Some(ref format) = self.format { match format { ApiStringFormat::Pattern(regex) => { if !(regex.regex_obj)().is_match(value) { bail!("value does not match the regex pattern"); } } ApiStringFormat::Enum(stringvec) => { if stringvec.iter().find(|&e| *e == value) == None { bail!("value '{}' is not defined in the enumeration.", value); } } ApiStringFormat::Complex(subschema) => { parse_property_string(value, subschema)?; } ApiStringFormat::VerifyFn(verify_fn) => { verify_fn(value)?; } } } Ok(()) } } #[derive(Debug)] pub struct ArraySchema { pub description: &'static str, pub items: &'static Schema, pub min_length: Option, pub max_length: Option, } impl ArraySchema { pub const fn new(description: &'static str, item_schema: &'static Schema) -> Self { ArraySchema { description, items: item_schema, min_length: None, max_length: None, } } pub const fn min_length(mut self, min_length: usize) -> Self { self.min_length = Some(min_length); self } pub const fn max_length(mut self, max_length: usize) -> Self { self.max_length = Some(max_length); self } pub const fn schema(self) -> Schema { Schema::Array(self) } fn check_length(&self, length: usize) -> Result<(), Error> { if let Some(min_length) = self.min_length { if length < min_length { bail!("array must contain at least {} elements", min_length); } } if let Some(max_length) = self.max_length { if length > max_length { bail!("array may only contain {} elements", max_length); } } Ok(()) } } /// Lookup table to Schema properties /// /// Stores a sorted list of (name, optional, schema) tuples: /// /// name: The name of the property /// optional: Set when the property is optional /// schema: Property type schema /// /// NOTE: The list has to be storted by name, because we use /// a binary search to find items. /// /// This is a workaround unless RUST can const_fn Hash::new() pub type SchemaPropertyMap = &'static [(&'static str, bool, &'static Schema)]; #[derive(Debug)] pub struct ObjectSchema { pub description: &'static str, pub additional_properties: bool, pub properties: SchemaPropertyMap, pub default_key: Option<&'static str>, } impl ObjectSchema { pub const fn new(description: &'static str, properties: SchemaPropertyMap) -> Self { ObjectSchema { description, properties, additional_properties: false, default_key: None, } } pub const fn additional_properties(mut self, additional_properties: bool) -> Self { self.additional_properties = additional_properties; self } pub const fn default_key(mut self, key: &'static str) -> Self { self.default_key = Some(key); self } pub const fn schema(self) -> Schema { Schema::Object(self) } pub fn lookup(&self, key: &str) -> Option<(bool, &Schema)> { if let Ok(ind) = self .properties .binary_search_by_key(&key, |(name, _, _)| name) { let (_name, optional, prop_schema) = self.properties[ind]; Some((optional, prop_schema)) } else { None } } } #[derive(Debug)] pub enum Schema { Null, Boolean(BooleanSchema), Integer(IntegerSchema), String(StringSchema), Object(ObjectSchema), Array(ArraySchema), } pub enum ApiStringFormat { Enum(&'static [&'static str]), Pattern(&'static ConstRegexPattern), Complex(&'static Schema), VerifyFn(fn(&str) -> Result<(), Error>), } impl std::fmt::Debug for ApiStringFormat { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { match self { ApiStringFormat::VerifyFn(fnptr) => write!(f, "VerifyFn({:p}", fnptr), ApiStringFormat::Enum(strvec) => write!(f, "Enum({:?}", strvec), ApiStringFormat::Pattern(regex) => write!(f, "Pattern({:?}", regex), ApiStringFormat::Complex(schema) => write!(f, "Complex({:?}", schema), } } } pub fn parse_boolean(value_str: &str) -> Result { match value_str.to_lowercase().as_str() { "1" | "on" | "yes" | "true" => Ok(true), "0" | "off" | "no" | "false" => Ok(false), _ => bail!("Unable to parse boolean option."), } } fn parse_property_string(value_str: &str, schema: &Schema) -> Result { println!("Parse property string: {}", value_str); let mut param_list: Vec<(String, String)> = vec![]; match schema { Schema::Object(object_schema) => { for key_val in value_str.split(',').filter(|s| !s.is_empty()) { let kv: Vec<&str> = key_val.splitn(2, '=').collect(); if kv.len() == 2 { param_list.push((kv[0].into(), kv[1].into())); } else if let Some(key) = object_schema.default_key { param_list.push((key.into(), kv[0].into())); } else { bail!("Value without key, but schema does not define a default key."); } } parse_parameter_strings(¶m_list, &object_schema, true).map_err(Error::from) } Schema::Array(array_schema) => { let mut array: Vec = vec![]; for value in value_str.split(',').filter(|s| !s.is_empty()) { match parse_simple_value(value, &array_schema.items) { Ok(res) => array.push(res), Err(err) => bail!("unable to parse array element: {}", err), } } array_schema.check_length(array.len())?; Ok(array.into()) } _ => bail!("Got unexpetec schema type."), } } pub fn parse_simple_value(value_str: &str, schema: &Schema) -> Result { let value = match schema { Schema::Null => { bail!("internal error - found Null schema."); } Schema::Boolean(_boolean_schema) => { let res = parse_boolean(value_str)?; Value::Bool(res) } Schema::Integer(integer_schema) => { let res: isize = value_str.parse()?; integer_schema.check_constraints(res)?; Value::Number(res.into()) } Schema::String(string_schema) => { string_schema.check_constraints(value_str)?; Value::String(value_str.into()) } _ => bail!("unable to parse complex (sub) objects."), }; Ok(value) } pub fn parse_parameter_strings( data: &[(String, String)], schema: &ObjectSchema, test_required: bool, ) -> Result { let mut params = json!({}); let mut errors = ParameterError::new(); let additional_properties = schema.additional_properties; for (key, value) in data { if let Some((_optional, prop_schema)) = schema.lookup(&key) { match prop_schema { Schema::Array(array_schema) => { if params[key] == Value::Null { params[key] = json!([]); } match params[key] { Value::Array(ref mut array) => { match parse_simple_value(value, &array_schema.items) { Ok(res) => array.push(res), // fixme: check_length?? Err(err) => { errors.push(format_err!("parameter '{}': {}", key, err)) } } } _ => errors.push(format_err!( "parameter '{}': expected array - type missmatch", key )), } } _ => match parse_simple_value(value, prop_schema) { Ok(res) => { if params[key] == Value::Null { params[key] = res; } else { errors.push(format_err!("parameter '{}': duplicate parameter.", key)); } } Err(err) => errors.push(format_err!("parameter '{}': {}", key, err)), }, } } else if additional_properties { match params[key] { Value::Null => { params[key] = Value::String(value.to_owned()); } Value::String(ref old) => { params[key] = Value::Array(vec![ Value::String(old.to_owned()), Value::String(value.to_owned()), ]); } Value::Array(ref mut array) => { array.push(Value::String(value.to_string())); } _ => errors.push(format_err!( "parameter '{}': expected array - type missmatch", key )), } } else { errors.push(format_err!( "parameter '{}': schema does not allow additional properties.", key )); } } if test_required && errors.len() == 0 { for (name, optional, _prop_schema) in schema.properties { if !(*optional) && params[name] == Value::Null { errors.push(format_err!( "parameter '{}': parameter is missing and it is not optional.", name )); } } } if !errors.is_empty() { Err(errors) } else { Ok(params) } } pub fn parse_query_string( query: &str, schema: &ObjectSchema, test_required: bool, ) -> Result { let param_list: Vec<(String, String)> = form_urlencoded::parse(query.as_bytes()) .into_owned() .collect(); parse_parameter_strings(¶m_list, schema, test_required) } pub fn verify_json(data: &Value, schema: &Schema) -> Result<(), Error> { match schema { Schema::Object(object_schema) => { verify_json_object(data, &object_schema)?; } Schema::Array(array_schema) => { verify_json_array(data, &array_schema)?; } Schema::Null => { if !data.is_null() { bail!("Expected Null, but value is not Null."); } } Schema::Boolean(boolean_schema) => verify_json_boolean(data, &boolean_schema)?, Schema::Integer(integer_schema) => verify_json_integer(data, &integer_schema)?, Schema::String(string_schema) => verify_json_string(data, &string_schema)?, } Ok(()) } pub fn verify_json_string(data: &Value, schema: &StringSchema) -> Result<(), Error> { if let Some(value) = data.as_str() { schema.check_constraints(value) } else { bail!("Expected string value."); } } pub fn verify_json_boolean(data: &Value, _schema: &BooleanSchema) -> Result<(), Error> { if !data.is_boolean() { bail!("Expected boolean value."); } Ok(()) } pub fn verify_json_integer(data: &Value, schema: &IntegerSchema) -> Result<(), Error> { if let Some(value) = data.as_i64() { schema.check_constraints(value as isize) } else { bail!("Expected integer value."); } } pub fn verify_json_array(data: &Value, schema: &ArraySchema) -> Result<(), Error> { let list = match data { Value::Array(ref list) => list, Value::Object(_) => bail!("Expected array - got object."), _ => bail!("Expected array - got scalar value."), }; schema.check_length(list.len())?; for item in list { verify_json(item, &schema.items)?; } Ok(()) } pub fn verify_json_object(data: &Value, schema: &ObjectSchema) -> Result<(), Error> { let map = match data { Value::Object(ref map) => map, Value::Array(_) => bail!("Expected object - got array."), _ => bail!("Expected object - got scalar value."), }; let additional_properties = schema.additional_properties; for (key, value) in map { if let Some((_optional, prop_schema)) = schema.lookup(&key) { match prop_schema { Schema::Object(object_schema) => { verify_json_object(value, object_schema)?; } Schema::Array(array_schema) => { verify_json_array(value, array_schema)?; } _ => verify_json(value, prop_schema)?, } } else if !additional_properties { bail!( "property '{}': schema does not allow additional properties.", key ); } } for (name, optional, _prop_schema) in schema.properties { if !(*optional) && data[name] == Value::Null { bail!( "property '{}': property is missing and it is not optional.", name ); } } Ok(()) } #[test] fn test_schema1() { let schema = Schema::Object(ObjectSchema { description: "TEST", additional_properties: false, properties: &[], default_key: None, }); println!("TEST Schema: {:?}", schema); } #[test] fn test_query_string() { { const SCHEMA: ObjectSchema = ObjectSchema::new( "Parameters.", &[("name", false, &StringSchema::new("Name.").schema())], ); let res = parse_query_string("", &SCHEMA, true); assert!(res.is_err()); } { const SCHEMA: ObjectSchema = ObjectSchema::new( "Parameters.", &[("name", true, &StringSchema::new("Name.").schema())], ); let res = parse_query_string("", &SCHEMA, true); assert!(res.is_ok()); } // TEST min_length and max_length { const SCHEMA: ObjectSchema = ObjectSchema::new( "Parameters.", &[( "name", true, &StringSchema::new("Name.") .min_length(5) .max_length(10) .schema(), )], ); let res = parse_query_string("name=abcd", &SCHEMA, true); assert!(res.is_err()); let res = parse_query_string("name=abcde", &SCHEMA, true); assert!(res.is_ok()); let res = parse_query_string("name=abcdefghijk", &SCHEMA, true); assert!(res.is_err()); let res = parse_query_string("name=abcdefghij", &SCHEMA, true); assert!(res.is_ok()); } // TEST regex pattern const_regex! { TEST_REGEX = "test"; TEST2_REGEX = "^test$"; } { const SCHEMA: ObjectSchema = ObjectSchema::new( "Parameters.", &[( "name", false, &StringSchema::new("Name.") .format(&ApiStringFormat::Pattern(&TEST_REGEX)) .schema(), )], ); let res = parse_query_string("name=abcd", &SCHEMA, true); assert!(res.is_err()); let res = parse_query_string("name=ateststring", &SCHEMA, true); assert!(res.is_ok()); } { const SCHEMA: ObjectSchema = ObjectSchema::new( "Parameters.", &[( "name", false, &StringSchema::new("Name.") .format(&ApiStringFormat::Pattern(&TEST2_REGEX)) .schema(), )], ); let res = parse_query_string("name=ateststring", &SCHEMA, true); assert!(res.is_err()); let res = parse_query_string("name=test", &SCHEMA, true); assert!(res.is_ok()); } // TEST string enums { const SCHEMA: ObjectSchema = ObjectSchema::new( "Parameters.", &[( "name", false, &StringSchema::new("Name.") .format(&ApiStringFormat::Enum(&["ev1", "ev2"])) .schema(), )], ); let res = parse_query_string("name=noenum", &SCHEMA, true); assert!(res.is_err()); let res = parse_query_string("name=ev1", &SCHEMA, true); assert!(res.is_ok()); let res = parse_query_string("name=ev2", &SCHEMA, true); assert!(res.is_ok()); let res = parse_query_string("name=ev3", &SCHEMA, true); assert!(res.is_err()); } } #[test] fn test_query_integer() { { const SCHEMA: ObjectSchema = ObjectSchema::new( "Parameters.", &[("count", false, &IntegerSchema::new("Count.").schema())], ); let res = parse_query_string("", &SCHEMA, true); assert!(res.is_err()); } { const SCHEMA: ObjectSchema = ObjectSchema::new( "Parameters.", &[( "count", true, &IntegerSchema::new("Count.") .minimum(-3) .maximum(50) .schema(), )], ); let res = parse_query_string("", &SCHEMA, true); assert!(res.is_ok()); let res = parse_query_string("count=abc", &SCHEMA, false); assert!(res.is_err()); let res = parse_query_string("count=30", &SCHEMA, false); assert!(res.is_ok()); let res = parse_query_string("count=-1", &SCHEMA, false); assert!(res.is_ok()); let res = parse_query_string("count=300", &SCHEMA, false); assert!(res.is_err()); let res = parse_query_string("count=-30", &SCHEMA, false); assert!(res.is_err()); let res = parse_query_string("count=50", &SCHEMA, false); assert!(res.is_ok()); let res = parse_query_string("count=-3", &SCHEMA, false); assert!(res.is_ok()); } } #[test] fn test_query_boolean() { { const SCHEMA: ObjectSchema = ObjectSchema::new( "Parameters.", &[("force", false, &BooleanSchema::new("Force.").schema())], ); let res = parse_query_string("", &SCHEMA, true); assert!(res.is_err()); } { const SCHEMA: ObjectSchema = ObjectSchema::new( "Parameters.", &[("force", true, &BooleanSchema::new("Force.").schema())], ); let res = parse_query_string("", &SCHEMA, true); assert!(res.is_ok()); let res = parse_query_string("a=b", &SCHEMA, true); assert!(res.is_err()); let res = parse_query_string("force", &SCHEMA, true); assert!(res.is_err()); let res = parse_query_string("force=yes", &SCHEMA, true); assert!(res.is_ok()); let res = parse_query_string("force=1", &SCHEMA, true); assert!(res.is_ok()); let res = parse_query_string("force=On", &SCHEMA, true); assert!(res.is_ok()); let res = parse_query_string("force=TRUE", &SCHEMA, true); assert!(res.is_ok()); let res = parse_query_string("force=TREU", &SCHEMA, true); assert!(res.is_err()); let res = parse_query_string("force=NO", &SCHEMA, true); assert!(res.is_ok()); let res = parse_query_string("force=0", &SCHEMA, true); assert!(res.is_ok()); let res = parse_query_string("force=off", &SCHEMA, true); assert!(res.is_ok()); let res = parse_query_string("force=False", &SCHEMA, true); assert!(res.is_ok()); } } #[test] fn test_verify_function() { const SCHEMA: ObjectSchema = ObjectSchema::new( "Parameters.", &[( "p1", false, &StringSchema::new("P1") .format(&ApiStringFormat::VerifyFn(|value| { if value == "test" { return Ok(()); }; bail!("format error"); })) .schema(), )], ); let res = parse_query_string("p1=tes", &SCHEMA, true); assert!(res.is_err()); let res = parse_query_string("p1=test", &SCHEMA, true); assert!(res.is_ok()); } #[test] fn test_verify_complex_object() { const NIC_MODELS: ApiStringFormat = ApiStringFormat::Enum(&["e1000", "virtio"]); const PARAM_SCHEMA: Schema = ObjectSchema::new( "Properties.", &[ ( "enable", true, &BooleanSchema::new("Enable device.").schema(), ), ( "model", false, &StringSchema::new("Ethernet device Model.") .format(&NIC_MODELS) .schema(), ), ], ) .default_key("model") .schema(); const SCHEMA: ObjectSchema = ObjectSchema::new( "Parameters.", &[( "net0", false, &StringSchema::new("First Network device.") .format(&ApiStringFormat::Complex(&PARAM_SCHEMA)) .schema(), )], ); let res = parse_query_string("", &SCHEMA, true); assert!(res.is_err()); let res = parse_query_string("test=abc", &SCHEMA, true); assert!(res.is_err()); let res = parse_query_string("net0=model=abc", &SCHEMA, true); assert!(res.is_err()); let res = parse_query_string("net0=model=virtio", &SCHEMA, true); assert!(res.is_ok()); let res = parse_query_string("net0=model=virtio,enable=1", &SCHEMA, true); assert!(res.is_ok()); let res = parse_query_string("net0=virtio,enable=no", &SCHEMA, true); assert!(res.is_ok()); } #[test] fn test_verify_complex_array() { { const PARAM_SCHEMA: Schema = ArraySchema::new("Integer List.", &IntegerSchema::new("Soemething").schema()).schema(); const SCHEMA: ObjectSchema = ObjectSchema::new( "Parameters.", &[( "list", false, &StringSchema::new("A list on integers, comma separated.") .format(&ApiStringFormat::Complex(&PARAM_SCHEMA)) .schema(), )], ); let res = parse_query_string("", &SCHEMA, true); assert!(res.is_err()); let res = parse_query_string("list=", &SCHEMA, true); assert!(res.is_ok()); let res = parse_query_string("list=abc", &SCHEMA, true); assert!(res.is_err()); let res = parse_query_string("list=1", &SCHEMA, true); assert!(res.is_ok()); let res = parse_query_string("list=2,3,4,5", &SCHEMA, true); assert!(res.is_ok()); } { const PARAM_SCHEMA: Schema = ArraySchema::new("Integer List.", &IntegerSchema::new("Soemething").schema()) .min_length(1) .max_length(3) .schema(); const SCHEMA: ObjectSchema = ObjectSchema::new( "Parameters.", &[( "list", false, &StringSchema::new("A list on integers, comma separated.") .format(&ApiStringFormat::Complex(&PARAM_SCHEMA)) .schema(), )], ); let res = parse_query_string("list=", &SCHEMA, true); assert!(res.is_err()); let res = parse_query_string("list=1,2,3", &SCHEMA, true); assert!(res.is_ok()); let res = parse_query_string("list=2,3,4,5", &SCHEMA, true); assert!(res.is_err()); } }