[squeak-dev] The Trunk: JSON-ul.52.mcz
commits at source.squeak.org
commits at source.squeak.org
Thu Sep 8 14:49:45 UTC 2022
Christoph Thiede uploaded a new version of JSON to project The Trunk:
http://source.squeak.org/trunk/JSON-ul.52.mcz
==================== Summary ====================
Name: JSON-ul.52
Author: ul
Time: 28 March 2020, 5:14:19.385987 am
UUID: ce84535f-78e3-483e-b833-f6ac1d4e0f54
Ancestors: JSON-ul.51
- tightened up the range of possible valid decimal exponents
==================== Snapshot ====================
SystemOrganization addCategory: #JSON!
----- Method: Integer>>jsonWriteOn: (in category '*JSON-writing') -----
jsonWriteOn: aWriteStream
^ self printOn: aWriteStream base: 10
!
----- Method: Association>>jsonWriteOn: (in category '*JSON-writing') -----
jsonWriteOn: aStream
self key asString jsonWriteOn: aStream.
aStream nextPut: $:; space.
self value jsonWriteOn: aStream.!
----- Method: False>>jsonWriteOn: (in category '*JSON-writing') -----
jsonWriteOn: aStream
aStream nextPutAll: 'false'!
----- Method: Number>>jsonWriteOn: (in category '*JSON-writing') -----
jsonWriteOn: aWriteStream
self printOn: aWriteStream base: 10!
OrderedDictionary subclass: #OrderedJsonObject
instanceVariableNames: ''
classVariableNames: ''
poolDictionaries: ''
category: 'JSON'!
----- Method: OrderedJsonObject class>>fromAssociations: (in category 'as yet unclassified') -----
fromAssociations: collectionOfAssociations
| result |
result := self new.
collectionOfAssociations do: [:each |
result at: each key put: each value ].
^ result!
----- Method: OrderedJsonObject>>at: (in category 'accessing') -----
at: aKey
"make it work more like javascript objects"
^ self at: aKey ifAbsent: [nil]!
----- Method: OrderedJsonObject>>at:put: (in category 'accessing') -----
at: aString put: anObject
aString isString ifFalse: [ self error: 'String expected' ].
super at: aString put: anObject.
^self!
----- Method: OrderedJsonObject>>doesNotUnderstand: (in category 'error handling') -----
doesNotUnderstand: aMessage
| key precedence |
key := aMessage selector.
(precedence := key precedence) = 1 ifTrue: [ ^self at: key ifAbsent: nil ].
(precedence = 3 and: [ (key indexOf: $:) = key size ]) ifTrue: [
^self
at: key allButLast asSymbol
put: aMessage arguments first ].
^super doesNotUnderstand: aMessage!
----- Method: OrderedJsonObject>>name (in category 'accessing') -----
name
"override 'cause Object defines this"
^self at: 'name'!
----- Method: OrderedJsonObject>>value (in category 'accessing') -----
value
"override 'cause Object defines this"
^self at: 'value'!
----- Method: Time>>jsonWriteOn: (in category '*JSON') -----
jsonWriteOn: stream
stream nextPut: $".
self print24: true showSeconds: true on: stream.
stream nextPut: $"!
----- Method: WriteStream>>jsonPrint: (in category '*json-printing') -----
jsonPrint: anObject
anObject jsonWriteOn: self!
----- Method: Text>>jsonWriteOn: (in category '*json-printing') -----
jsonWriteOn: aStream
self string jsonWriteOn: aStream!
----- Method: UndefinedObject>>jsonWriteOn: (in category '*JSON-writing') -----
jsonWriteOn: aWriteStream
aWriteStream nextPutAll: 'null'!
Error subclass: #JsonSyntaxError
instanceVariableNames: ''
classVariableNames: ''
poolDictionaries: ''
category: 'JSON'!
!JsonSyntaxError commentStamp: 'tonyg 4/29/2016 11:06' prior: 0!
Class Json signals (possibly-indirect) instances of me when reading a JSON value from an input stream fails.!
JsonSyntaxError subclass: #JsonIncompleteError
instanceVariableNames: ''
classVariableNames: ''
poolDictionaries: ''
category: 'JSON'!
!JsonIncompleteError commentStamp: 'tonyg 4/29/2016 11:37' prior: 0!
I signal that reading a JSON value failed because more input is required, but that the input seen so far was not incorrect. Compare to JsonInvalidError.
Be warned that reading numbers directly out of a stream can be ambiguous!!
Consider reading from '1234'. Is the result intended to be 1234, or is there missing input, and the next character will be '5', making the result (possibly) 12345?!
JsonSyntaxError subclass: #JsonInvalidError
instanceVariableNames: ''
classVariableNames: ''
poolDictionaries: ''
category: 'JSON'!
!JsonInvalidError commentStamp: 'tonyg 4/29/2016 11:06' prior: 0!
I signal that reading a JSON value failed because the input didn't match the (extended)JSON grammar implemented by class Json.!
----- Method: Dictionary>>jsonWriteOn: (in category '*JSON-writing') -----
jsonWriteOn: aStream
| needComma |
needComma := false.
aStream nextPut: ${.
self associationsDo: [ :assoc |
needComma
ifTrue: [ aStream nextPut: $, ]
ifFalse: [ needComma := true ].
assoc key jsonWriteOn: aStream.
aStream nextPut: $:.
assoc value jsonWriteOn: aStream ].
aStream nextPut: $}.!
Dictionary subclass: #JsonObject
instanceVariableNames: ''
classVariableNames: ''
poolDictionaries: ''
category: 'JSON'!
----- Method: JsonObject class>>fromAssociations: (in category 'as yet unclassified') -----
fromAssociations: collectionOfAssociations
| result |
result := self new.
collectionOfAssociations do: [:each |
result at: each key put: each value ].
^ result!
----- Method: JsonObject>>at: (in category 'accessing') -----
at: aKey
"make it work more like javascript objects"
^ self at: aKey ifAbsent: [nil]!
----- Method: JsonObject>>at:put: (in category 'accessing') -----
at: aString put: anObject
aString isString ifFalse: [ self error: 'String expected' ].
super at: aString put: anObject.
^self!
----- Method: JsonObject>>doesNotUnderstand: (in category 'error handling') -----
doesNotUnderstand: aMessage
| key precedence |
key := aMessage selector.
(precedence := key precedence) = 1 ifTrue: [ ^self at: key ifAbsent: nil ].
(precedence = 3 and: [ (key indexOf: $:) = key size ]) ifTrue: [
^self
at: key allButLast asSymbol
put: aMessage arguments first ].
^super doesNotUnderstand: aMessage!
----- Method: JsonObject>>name (in category 'accessing') -----
name
"override 'cause Object defines this"
^self at: 'name'!
----- Method: JsonObject>>value (in category 'accessing') -----
value
"override 'cause Object defines this"
^self at: 'value'!
----- Method: True>>jsonWriteOn: (in category '*JSON-writing') -----
jsonWriteOn: aStream
aStream nextPutAll: 'true'!
NumberParser subclass: #JsonNumberParser
instanceVariableNames: 'fraction'
classVariableNames: ''
poolDictionaries: ''
category: 'JSON'!
----- Method: JsonNumberParser>>allowPlusSign (in category 'accessing') -----
allowPlusSign
^false!
----- Method: JsonNumberParser>>allowPlusSignInExponent (in category 'accessing') -----
allowPlusSignInExponent
^true!
----- Method: JsonNumberParser>>error: (in category 'error') -----
error: aString
JsonSyntaxError signal: aString!
----- Method: JsonNumberParser>>exponentLetters (in category 'accessing') -----
exponentLetters
^'eE'!
----- Method: JsonNumberParser>>initialize (in category 'initialize-release') -----
initialize
super initialize.
base := 10.
fraction := Fraction numerator: 0 denominator: 1!
----- Method: JsonNumberParser>>makeFloatFromMantissa:exponent: (in category 'parsing-private') -----
makeFloatFromMantissa: mantissa exponent: exponent
exponent = 0 ifTrue: [ ^mantissa asFloat ].
exponent >= 16 ifTrue: [
exponent > 324 ifTrue: [ "(Float emax + 53 * 2 ln / 10 ln) ceiling => 324"
mantissa isZero ifTrue: [ ^0.0 ].
mantissa positive ifTrue: [ ^Float infinity ].
^Float negativeInfinity ].
^(mantissa * (self tenRaisedTo: exponent)) asFloat ].
(exponent >= -15 and: [ mantissa highBitOfMagnitude <= 54 ]) ifTrue: [
exponent >= 1 ifTrue: [ ^mantissa asFloat * (self tenRaisedTo: exponent) asFloat ].
^mantissa asFloat / (self tenRaisedTo: exponent negated) asFloat ].
exponent < -324 ifTrue: [ "-1 * (53 - Float emin * 2 ln / 10 ln) ceiling => -324"
mantissa positive ifTrue: [ ^0.0 ].
^-0.0 ].
^(fraction setNumerator: mantissa denominator: (self tenRaisedTo: exponent negated)) asFloat!
----- Method: JsonNumberParser>>nextElementaryLargeInteger (in category 'parsing-large int') -----
nextElementaryLargeInteger
"Form an unsigned integer with incoming digits from sourceStream.
Return this integer, or zero if no digits found.
Stop reading if end of digits or if a LargeInteger is formed.
Count the number of digits and the position of lastNonZero digit and store them in instVar."
| digit value |
value := 0.
nDigits := 0.
lastNonZero := 0.
[
value isLarge ifTrue: [ ^value ].
((digit := (sourceStream next ifNil: [ ^value ]) asInteger - 48 "$0 asInteger") < 0
or: [ digit >= 10 ]) ifTrue: [
sourceStream skip: -1.
^value ].
nDigits := nDigits + 1.
digit = 0
ifFalse: [
(lastNonZero = 0 and: [ nDigits > 1 ]) ifTrue: [ self error: 'Leading zeroes are not allowed.' ].
lastNonZero := nDigits.
value := value * 10 + digit ]
ifTrue: [ value := value * 10 ] ] repeat!
----- Method: JsonNumberParser>>nextNumber: (in category 'parsing-public') -----
nextNumber: negative
| numberOfTrailingZeroInIntegerPart numberOfTrailingZeroInFractionPart numberOfNonZeroFractionDigits mantissa value |
integerPart := self nextUnsignedIntegerOrNil ifNil: [ ^self error: 'Missing integer part!!' ].
numberOfTrailingZeroInIntegerPart := nDigits - lastNonZero.
(sourceStream peekFor: $.) ifFalse: [ "No fraction part"
negative ifTrue: [ integerPart := integerPart negated ].
self readExponent ifFalse: [ ^integerPart ].
exponent > 0 ifTrue: [ ^integerPart * (self tenRaisedTo: exponent) ].
^(Fraction numerator: integerPart denominator: (self tenRaisedTo: exponent negated)) asFloat ].
fractionPart := self nextUnsignedIntegerOrNil ifNil: [ self error: 'Missing fraction part!!' ].
fractionPart isZero ifTrue: [
self readExponent ifFalse: [
negative ifTrue: [
integerPart isZero ifTrue: [ ^Float negativeZero ].
^integerPart negated ].
^integerPart ].
exponent >= 0 ifTrue: [
negative ifTrue: [ integerPart := integerPart negated ].
^integerPart * (self tenRaisedTo: exponent) ].
value := self makeFloatFromMantissa: integerPart exponent: exponent.
negative ifTrue: [ ^value negated ].
^value ].
numberOfTrailingZeroInFractionPart := nDigits - lastNonZero.
numberOfNonZeroFractionDigits := lastNonZero.
self readExponent.
exponent := exponent - numberOfNonZeroFractionDigits.
mantissa := integerPart * (self tenRaisedTo: numberOfNonZeroFractionDigits) + (fractionPart // (self tenRaisedTo: numberOfTrailingZeroInFractionPart)).
value := self makeFloatFromMantissa: mantissa exponent: exponent.
negative ifTrue: [ ^value negated ].
^value!
----- Method: JsonNumberParser>>nextUnsignedIntegerOrNil (in category 'parsing-public') -----
nextUnsignedIntegerOrNil
"Form an unsigned integer with incoming digits from sourceStream.
Answer this integer, or nil if no digit found.
Count the number of digits and the position of lastNonZero digit and store them in instVar"
| nPackets high nDigitsHigh lastNonZeroHigh low |
"read no more digits than one elementary LargeInteger"
high := self nextElementaryLargeInteger.
nDigits = 0 ifTrue: [^nil].
"Not enough digits to form a LargeInteger, stop iteration"
high isLarge ifFalse: [^high].
"We now have to engage arithmetic with LargeInteger
Decompose the integer in a high and low packets of growing size:"
nPackets := 1.
nDigitsHigh := nDigits.
lastNonZeroHigh := lastNonZero.
[
low := self nextLargeIntegerBase: 10 nPackets: nPackets .
high := high * (self tenRaisedTo: nDigits) + low.
lastNonZero = 0 ifFalse: [lastNonZeroHigh := lastNonZero + nDigitsHigh].
nDigitsHigh := nDigitsHigh + nDigits.
low isLarge]
whileTrue: [nPackets := nPackets * 2].
nDigits := nDigitsHigh.
lastNonZero := lastNonZeroHigh.
^high!
----- Method: JsonNumberParser>>tenRaisedTo: (in category 'parsing-private') -----
tenRaisedTo: anInteger
anInteger >= 0 ifFalse: [ ^10 raisedToInteger: anInteger ].
anInteger >= 16 ifTrue: [ ^10 raisedToInteger: anInteger ].
^#(1 10 100 1000 10000 100000 1000000 10000000 100000000 1000000000 10000000000 100000000000 1000000000000 10000000000000 100000000000000 1000000000000000) at: anInteger + 1!
----- Method: ScaledDecimal>>jsonWriteOn: (in category '*JSON-writing') -----
jsonWriteOn: stream
self printOn: stream showingDecimalPlaces: scale!
----- Method: Collection>>jsonWriteOn: (in category '*json') -----
jsonWriteOn: aStream
"By default, use array braces "
aStream nextPut: $[.
self do: [:each |
each jsonWriteOn: aStream
] separatedBy: [ aStream nextPut: $, ].
aStream nextPut: $]!
TestCase subclass: #JsonTests
instanceVariableNames: ''
classVariableNames: ''
poolDictionaries: ''
category: 'JSON'!
!JsonTests commentStamp: '<historical>' prior: 0!
I provide a number of test cases for class Json.!
----- Method: JsonTests>>assertIncompleteJson: (in category 'helpers') -----
assertIncompleteJson: aString
self should: [self readFrom: aString] raise: JsonIncompleteError!
----- Method: JsonTests>>assertInvalidJson: (in category 'helpers') -----
assertInvalidJson: aString
self should: [self readFrom: aString] raise: JsonInvalidError!
----- Method: JsonTests>>json:equals: (in category 'helpers') -----
json: aString equals: aValue
| readValue |
readValue := self readFrom: aString.
self assert: readValue = aValue.!
----- Method: JsonTests>>readFrom: (in category 'helpers') -----
readFrom: aString
^ (Json newWithConstructors: {JsonDummyTestObject.}) readFrom: aString readStream
!
----- Method: JsonTests>>render:equals: (in category 'helpers') -----
render: anObject equals: aString
self assert: (Json render: anObject) = aString!
----- Method: JsonTests>>simpleDummyObject (in category 'helpers') -----
simpleDummyObject
^ JsonDummyTestObject new a: 1; b: 2; c: 3; yourself!
----- Method: JsonTests>>testArray (in category 'tests') -----
testArray
self json: '[]' equals: #().
self json: '[[]]' equals: #(#()).
self json: '[[], []]' equals: #(#() #()).
self json: '["hi", "there"]' equals: #('hi' 'there').
self json: '[["a", "b", null]]' equals: #(('a' 'b' nil)).!
----- Method: JsonTests>>testAtomFalse (in category 'tests') -----
testAtomFalse
self json: 'false' equals: false.
self json: ' false' equals: false.
self json: 'false ' equals: false.
self json: ' false ' equals: false.
!
----- Method: JsonTests>>testAtomNull (in category 'tests') -----
testAtomNull
self json: 'null' equals: nil.
self json: ' null' equals: nil.
self json: 'null ' equals: nil.
self json: ' null ' equals: nil.
!
----- Method: JsonTests>>testAtomNumber (in category 'tests') -----
testAtomNumber
self json: '1' equals: 1.
self json: '123' equals: 123.
self should: [ self json: '0123' equals: 123 ] raise: JsonSyntaxError. "No leading zeroes."
self json: '1.23e2' equals: 123.
self json: '-1' equals: -1.
self json: '-0' equals: 0.
self json: '[-1.2]' equals: #(-1.2).!
----- Method: JsonTests>>testAtomString (in category 'tests') -----
testAtomString
self json: '"hi"' equals: 'hi'.
self json: '"\""' equals: '"'.
self json: '"\\"' equals: '\'.
self json: '""' equals: ''.
self json: '"a\u0004b"' equals: ({$a. Character value: 4. $b} as: String).
self json: '"a\nb"' equals: ({$a. Character lf. $b} as: String).!
----- Method: JsonTests>>testAtomTrue (in category 'tests') -----
testAtomTrue
self json: 'true' equals: true.
self json: ' true' equals: true.
self json: 'true ' equals: true.
self json: ' true ' equals: true.
!
----- Method: JsonTests>>testCtor (in category 'tests') -----
testCtor
self json: '@JsonDummyTestObject {"a": 1, "b": 2, "c": 3}' equals: self simpleDummyObject.
self json: (Json render: self simpleDummyObject) equals: self simpleDummyObject.!
----- Method: JsonTests>>testDictionary (in category 'tests') -----
testDictionary
self json: '{}' equals: (JsonObject new).
self json: '{"a": "a"}' equals: (JsonObject new at: 'a' put: 'a'; yourself).
self json: '{"a": [[]]}' equals: (JsonObject new at: 'a' put: #(#()); yourself).
self json: '{"a":"b", "b":"a"}' equals: (JsonObject new add: 'a'->'b'; add: 'b'->'a';yourself).!
----- Method: JsonTests>>testDictionaryClass (in category 'tests') -----
testDictionaryClass
| parser |
parser := Json new.
self assert: (parser readFrom: '{}' readStream) class == JsonObject.
parser dictionaryClass: OrderedJsonObject.
self assert: (parser readFrom: '{}' readStream) class == OrderedJsonObject.
self assert: (parser readFrom: '{"x":{"y":{}}}' readStream) x y class == OrderedJsonObject!
----- Method: JsonTests>>testIncomplete (in category 'tests') -----
testIncomplete
self assertIncompleteJson: ''.
self assertIncompleteJson: ' '.
self assertIncompleteJson: ' tr'.
self assertIncompleteJson: 'tru'.
self assertIncompleteJson: '['.
self assertIncompleteJson: '[true'.
self assertIncompleteJson: '[true,'.
self assertIncompleteJson: '{'.
self assertIncompleteJson: '{"hi"'.
self assertIncompleteJson: '{"hi":'.
self assertIncompleteJson: '{"hi":true'.
self assertIncompleteJson: '{"hi":true,'.
self assertIncompleteJson: '{"hi":true,"'.
self assertIncompleteJson: '"hello'.
self assertIncompleteJson: '"hello '.
self assertIncompleteJson: '"hello\'.
self assertIncompleteJson: '"\u26'.!
----- Method: JsonTests>>testInvalid (in category 'tests') -----
testInvalid
self assertInvalidJson: 'x'.
self assertInvalidJson: ' x'.
self assertInvalidJson: ' trx'.
self assertInvalidJson: 'trux'.
self assertInvalidJson: '.'.
self assertInvalidJson: ':'.
self assertInvalidJson: ','.
self assertInvalidJson: ']'.
self assertInvalidJson: '}'.
self assertInvalidJson: '[x'.
self assertInvalidJson: '[true t'.
self assertInvalidJson: '[true,]'.
self assertInvalidJson: '{]'.
self assertInvalidJson: '{,'.
self assertInvalidJson: '{"hi",'.
self assertInvalidJson: '{"hi":x'.
self assertInvalidJson: '{"hi":,'.
self assertInvalidJson: '{"hi":true "'.
self assertInvalidJson: '{"hi":true,}'.
self assertInvalidJson: '\u263A'.!
----- Method: JsonTests>>testInvalidUnicodeEscapes (in category 'tests') -----
testInvalidUnicodeEscapes
self assertInvalidJson: '"\u26"'. "Note that naively reading four chars runs off the end here, so we might see JsonIncompleteError, which would be wrong."
self assertInvalidJson: '"\u2Z"'.
self assertInvalidJson: '"\u2Z44"'.!
----- Method: JsonTests>>testJsonObjectAtPutReturnsTheObject (in category 'tests') -----
testJsonObjectAtPutReturnsTheObject
{ JsonObject. OrderedJsonObject } do: [ :jsonObjectClass |
| json |
json := jsonObjectClass new.
self assert: (json at: 'foo' put: 1) == json.
self assert: (json foo: 1) == json ]!
----- Method: JsonTests>>testMissingCtor (in category 'tests') -----
testMissingCtor
self assertInvalidJson: '@Missing[]'!
----- Method: JsonTests>>testMissingCtorNoMap (in category 'tests') -----
testMissingCtorNoMap
self
should: [Json new readFrom: '@Missing[]' readStream]
raise: JsonInvalidError!
----- Method: JsonTests>>testNonStringKeysRaiseError (in category 'tests') -----
testNonStringKeysRaiseError
{ JsonObject. OrderedJsonObject } do: [ :jsonObjectClass |
| json |
json := jsonObjectClass new.
self should: [ json at: 1 put: 1 ] raise: Error.
self assert: json isEmpty.
json at: '1' put: 1.
self assert: 1 equals: (json at: '1') ]!
----- Method: JsonTests>>testStreaming (in category 'tests') -----
testStreaming
| j |
j := Json new stream: 'truefalsetrue[]{}1.234 5.678"A""B"nullnull' readStream.
self assert: j readAny equals: true.
self assert: j readAny equals: false.
self assert: j readAny equals: true.
self assert: j readAny equals: #().
self assert: j readAny equals: JsonObject new.
self assert: j readAny equals: 1.234.
self assert: j readAny equals: 5.678.
self assert: j readAny equals: 'A'.
self assert: j readAny equals: 'B'.
self assert: j readAny equals: nil.
self assert: j readAny equals: nil.!
----- Method: JsonTests>>testStringWithUnicode (in category 'tests') -----
testStringWithUnicode
| unicodeString |
unicodeString := (Unicode value: 16r263A) asString.
self json: '"\u263A"' equals:unicodeString.
self json: '"\u263a"' equals:unicodeString.
self json: '"', unicodeString, '"' equals: unicodeString.
self render: unicodeString equals: '"', unicodeString, '"'.!
----- Method: JsonTests>>testWriteAssociation (in category 'tests') -----
testWriteAssociation
self render: 'key' -> 'value' equals: '"key": "value"'.
self render: 'key' -> 2 equals: '"key": 2'.
"keys should be strings"
self render: 42 -> 2 equals: '"42": 2'.
"try to do _something_ for more complex keys"
self render: #(42 43 44) -> 2 equals: '"#(42 43 44)": 2'.
!
----- Method: JsonTests>>testWriteString (in category 'tests') -----
testWriteString
self render: '"' equals: '"\""'.
self render: '\' equals: '"\\"'.
self render: 'hi' equals: '"hi"'.
self render: ({$a. Character lf. $b} as: String) equals: '"a\nb"'.
self render: ({$a. Character value: 4. $b} as: String) equals: '"a\u0004b"'.!
----- Method: String>>asSerializedJson (in category '*JSON') -----
asSerializedJson
" Assume that the receiver is a valid serialized json string.
Return an object that understands #jsonWriteOn: and will
write this string on its argument. "
^SerializedJson on: self!
----- Method: String>>jsonWriteOn: (in category '*JSON-writing') -----
jsonWriteOn: aStream
| index start |
aStream nextPut: $".
start := 1.
[ (index := self indexOfAnyOf: Json escapeSet startingAt: start) = 0 ] whileFalse: [
aStream next: index - start putAll: self startingAt: start.
aStream nextPutAll: (Json escapeForCharacter: (self at: index)).
start := index + 1 ].
start <= self size ifTrue: [
aStream next: self size + 1 - start putAll: self startingAt: start ].
aStream nextPut: $".
!
----- Method: String>>parseAsJson (in category '*JSON') -----
parseAsJson
"Convenience"
^Json readFrom: self readStream!
----- Method: String>>parseAsOrderedJson (in category '*JSON') -----
parseAsOrderedJson
"Convenience"
^Json new
dictionaryClass: OrderedJsonObject;
readFrom: self readStream!
Object subclass: #Json
instanceVariableNames: 'stream currentCharacter arrayBufferStream stringBufferStream numberParser ctorMap dictionaryClass'
classVariableNames: ''
poolDictionaries: ''
category: 'JSON'!
Json class
instanceVariableNames: 'escapeArray escapeSet'!
!Json commentStamp: 'ul 3/29/2016 04:38' prior: 0!
I support reading and writing JSON (see http://json.org) formatted data - strings, numbers, boolean, nil, arrays and dictionaries.
The implementation is mainly based on RFC 7159 (https://www.ietf.org/rfc/rfc7159.txt). It has been extended with syntax for invoking a prearranged list of constructors on read objects.
Character encoding is not handled here. That's something you have to do before reading or after writing. Mixed processing is possible, but it's entirely your responsibility to keep things correct.
Instance Variables
stream: <PositionableStream>
currentCharacter: <Character>
arrayBufferStream: <WriteStream>
stringBufferStream: <ReadWriteStream>
numberParser: <ExtendedNumberParser>
ctorMap: <Dictionary>
For parsing, stream has to be initialized by sending #readFrom: to my instance. The parser will pre-read one character, which will be stored in currentCharacter, so the stream is expected to support position manipulation, hence it should be a PositionableStream.
arrayBufferStream is WriteStream on an Array, which holds the values during array parsing (see #readArray). When there's a recursive call, this stream is used as a stack to separate the elements parsed in the previous invocation from the current one.
stringBufferStream is a ReadWriteStream on a String, which holds the currently parsed String (see #readString), the currently parsed number (see #readNumber) or the name of the currently parsed constructor (see #readConstructor). Recursion has no effect on this.
numberParser is a cached instance of ExtendedNumberParser. It's initialized on stringBufferStream, so it can quickly parse the number stored in it.
ctorMap is the Dictionary holding the constructor classes by name.
arrayBufferStream, stringBufferStream and numberParser are initialized lazily, and should not be accessed externally. Since these are shared objects, along with stream and currentCharacter, holding state, therefore a single instance of me shouldn't be used to parse multiple streams at the same time.
For writing, you can use the methods in the class-side rendering category. To convert individual objects to a string, you can use #asJsonString, to serialize it on a stream, you can use #jsonWriteOn:.
!
Json class
instanceVariableNames: 'escapeArray escapeSet'!
----- Method: Json class>>escapeForCharacter: (in category 'accessing') -----
escapeForCharacter: c
| asciiValue |
(asciiValue := c asciiValue) < 128
ifTrue: [ ^escapeArray at: asciiValue + 1 ].
^nil!
----- Method: Json class>>escapeSet (in category 'accessing') -----
escapeSet
^escapeSet!
----- Method: Json class>>initialize (in category 'class initialization') -----
initialize
"Json initialize."
| newEscapeArray newEscapeSet |
newEscapeArray := Array new: 128.
newEscapeSet := CharacterSet new.
(0 to: 31), #(127) do: [ :each |
newEscapeArray at: each + 1 put: '\u', (each printStringHex padded: #left to: 4 with: $0).
newEscapeSet add: (Character value: each) ].
{
$" -> '\"'.
$\ -> '\\'.
$/ -> '\/'. "A hack, so the generated JSON will always be HTML+Javascript compatible, because the generated JSON will not contain the seqence </script>."
Character backspace -> '\b'.
Character lf -> '\n'.
Character newPage -> '\f'.
Character cr -> '\r'.
Character tab -> '\t'.
} do: [ :each |
newEscapeArray at: each key asciiValue + 1 put: each value.
newEscapeSet add: each key ].
escapeArray := newEscapeArray.
escapeSet := newEscapeSet!
----- Method: Json class>>mimeType (in category 'accessing') -----
mimeType
^ 'application/x-json'!
----- Method: Json class>>newWithConstructors: (in category 'instance creation') -----
newWithConstructors: aCollection
| m |
m := Dictionary new.
aCollection do: [:each |
(each isKindOf: Association)
ifTrue: [m add: each]
ifFalse: [m at: each name asString put: each]].
^ self new ctorMap: m; yourself.!
----- Method: Json class>>readFrom: (in category 'instance creation') -----
readFrom: aStream
^ self new readFrom: aStream.!
----- Method: Json class>>render: (in category 'rendering') -----
render: anObject
^String streamContents: [ :stream |
anObject jsonWriteOn: stream ]!
----- Method: Json class>>render:withConstructor:on: (in category 'rendering') -----
render: anObject withConstructor: aConstructorName on: aStream
aStream nextPutAll: '@', aConstructorName.
anObject jsonWriteOn: aStream.
!
----- Method: Json class>>renderInstanceVariables:of:on: (in category 'rendering') -----
renderInstanceVariables: aCollection of: anObject on: aStream
| map |
map := Dictionary new.
aCollection do: [:ivarName | map at: ivarName put: (anObject instVarNamed: ivarName)].
self render: map withConstructor: anObject class name asString on: aStream!
----- Method: Json>>arrayBufferStream (in category 'private') -----
arrayBufferStream
^arrayBufferStream ifNil: [ arrayBufferStream := (Array new: 10) writeStream ]!
----- Method: Json>>consume: (in category 'private') -----
consume: aString
| message |
1 to: aString size do: [ :index |
(currentCharacter := stream next) == (aString at: index) ifFalse: [
message := 'Expected ', (aString at: index) printString.
currentCharacter
ifNil: [ self incomplete: message ]
ifNotNil: [ self invalid: message ] ] ].
currentCharacter := stream next!
----- Method: Json>>ctorMap (in category 'accessing') -----
ctorMap
^ ctorMap!
----- Method: Json>>ctorMap: (in category 'accessing') -----
ctorMap: m
ctorMap := m!
----- Method: Json>>dictionaryClass: (in category 'accessing') -----
dictionaryClass: aClass
"This method allows you to override the default dictionary class to be created while parsing a stream. Instances of aClass are expected to understand #at:put:."
dictionaryClass := aClass!
----- Method: Json>>error: (in category 'error handling') -----
error: aString
(currentCharacter isNil and: [ stream atEnd ])
ifTrue: [ self incomplete: aString ]
ifFalse: [ self invalid: aString ]!
----- Method: Json>>incomplete: (in category 'error handling') -----
incomplete: aString
JsonIncompleteError signal: aString!
----- Method: Json>>initialize (in category 'initialize-release') -----
initialize
dictionaryClass := JsonObject
!
----- Method: Json>>interpretStringEscape: (in category 'private') -----
interpretStringEscape: aCharacter
aCharacter == $b ifTrue: [ ^Character backspace ].
aCharacter == $n ifTrue: [ ^Character lf ].
aCharacter == $f ifTrue: [ ^Character newPage ].
aCharacter == $r ifTrue: [ ^Character cr ].
aCharacter == $t ifTrue: [ ^Character tab ].
aCharacter == $u ifTrue: [ ^self unescapeUnicode ].
aCharacter == $" ifTrue: [ ^aCharacter ].
aCharacter == $\ ifTrue: [ ^aCharacter ].
aCharacter == $/ ifTrue: [ ^aCharacter ].
self error: 'Unexpected escaped character: ', aCharacter asString
!
----- Method: Json>>invalid: (in category 'error handling') -----
invalid: aString
JsonInvalidError signal: aString!
----- Method: Json>>readAny (in category 'private') -----
readAny
self skipWhitespace.
currentCharacter == ${ ifTrue: [ ^self readDictionary ].
currentCharacter == $[ ifTrue: [ ^self readArray ].
currentCharacter == $" ifTrue: [ ^self readString ].
currentCharacter == $t ifTrue: [ self consume: 'rue'. ^true ].
currentCharacter == $f ifTrue: [ self consume: 'alse'. ^false ].
currentCharacter == $n ifTrue: [ self consume: 'ull'. ^nil ].
currentCharacter == $- ifTrue: [ ^self readNumber: true ].
(#($0 $1 $2 $3 $4 $5 $6 $7 $8 $9) instVarsInclude: currentCharacter) ifTrue: [
^self readNumber: false ].
currentCharacter == $@ ifTrue: [ ^self readConstructor ].
self invalid: 'Unknown Json input'!
----- Method: Json>>readArray (in category 'private') -----
readArray
| initialPosition |
currentCharacter := stream next.
self skipWhitespace.
currentCharacter == $] ifTrue: [
currentCharacter := stream next.
^#() ].
initialPosition := self arrayBufferStream position.
[
arrayBufferStream nextPut: self readAny.
self skipWhitespace.
currentCharacter == $] ifTrue: [
| result |
result := arrayBufferStream originalContents copyFrom: initialPosition + 1 to: arrayBufferStream position.
arrayBufferStream position: initialPosition.
currentCharacter := stream next.
^result ].
currentCharacter == $, ifFalse: [ self error: 'Unexpected character: ', currentCharacter asString ].
currentCharacter := stream next ] repeat.
!
----- Method: Json>>readConstructor (in category 'private') -----
readConstructor
ctorMap ifNil: [ ^self error: 'No constructors were declared.' ].
self resetStringBufferStream.
[ (currentCharacter := stream next) == $. or: [ currentCharacter isLetter ] ] whileTrue: [
stringBufferStream nextPut: currentCharacter ].
(ctorMap at: stringBufferStream contents ifAbsent: nil) ifNotNil: [ :constructor |
^constructor constructFromJson: self readAny ].
self error: 'Unknown constructor: ', stringBufferStream contents!
----- Method: Json>>readDictionary (in category 'private') -----
readDictionary
| result key commaNeeded |
result := dictionaryClass new.
commaNeeded := false.
currentCharacter := stream next.
[
self skipWhitespace.
currentCharacter == $} ifTrue: [
currentCharacter := stream next.
^result ].
commaNeeded
ifFalse: [ commaNeeded := true ]
ifTrue: [
currentCharacter == $, ifFalse: [ self error: 'Missing comma' ].
currentCharacter := stream next.
self skipWhitespace ].
currentCharacter == $" ifFalse: [ self error: 'Key in dictionary must be string' ].
key := self readString.
self skipWhitespace.
currentCharacter == $: ifFalse: [ self error: 'Missing colon' ].
currentCharacter := stream next.
result at: key put: self readAny ] repeat!
----- Method: Json>>readFrom: (in category 'parsing') -----
readFrom: aStream
| result |
stream := aStream.
numberParser ifNotNil: [ numberParser on: stream ].
currentCharacter := stream next.
result := self readAny.
currentCharacter ifNotNil: [ stream skip: -1 ]. "Undo prereading."
^result!
----- Method: Json>>readNumber: (in category 'private') -----
readNumber: negative
| result |
negative ifFalse: [ stream skip: -1 ].
result := (numberParser ifNil: [
numberParser := JsonNumberParser new
on: stream;
failBlock: [ self error: 'Invalid number.' ];
yourself ])
nextNumber: negative.
currentCharacter := stream next.
^result
!
----- Method: Json>>readString (in category 'private') -----
readString
self resetStringBufferStream.
[
currentCharacter := stream next ifNil: [self incomplete: 'Unexpected end of string' ].
currentCharacter == $" ifTrue: [
currentCharacter := stream next.
^stringBufferStream contents ].
currentCharacter == $\
ifTrue: [
stringBufferStream nextPut: (self interpretStringEscape: (stream next ifNil: [
self incomplete: 'Unexpected end of string' ])) ]
ifFalse: [ stringBufferStream nextPut: currentCharacter ] ] repeat!
----- Method: Json>>resetStringBufferStream (in category 'private') -----
resetStringBufferStream
stringBufferStream
ifNil: [ stringBufferStream := ReadWriteStream on: (String new: 64) ]
ifNotNil: [ stringBufferStream resetToStart ]!
----- Method: Json>>skipWhitespace (in category 'private') -----
skipWhitespace
currentCharacter ifNil: [
self incomplete: 'Input stream is empty' ].
[ currentCharacter isSeparator ] whileTrue: [
currentCharacter := stream next ifNil: [
self incomplete: 'Input stream is empty' ]. ]!
----- Method: Json>>stream (in category 'accessing') -----
stream
"Answer the value of stream"
^ stream!
----- Method: Json>>stream: (in category 'private') -----
stream: aStream
"For testing purposes only"
stream := aStream.
numberParser ifNotNil: [ numberParser on: stream ].
currentCharacter := stream next!
----- Method: Json>>unescapeUnicode (in category 'private') -----
unescapeUnicode
| code digitValue |
code := 0.
1 to: 4 do: [ :index |
(digitValue := (stream next ifNil: [ self incomplete: 'Unexpected end of stream' ]) digitValue) < 0 ifTrue: [
self invalid: 'Invalid hexadecimal digit' ].
digitValue < 16
ifTrue: [ code := code * 16 + digitValue ]
ifFalse: [ self invalid: 'Invalid hexadecimal digit' ] ].
^Character value: code!
Object subclass: #JsonDummyTestObject
instanceVariableNames: 'a b c'
classVariableNames: ''
poolDictionaries: ''
category: 'JSON'!
----- Method: JsonDummyTestObject class>>constructFromJson: (in category 'as yet unclassified') -----
constructFromJson: j
^ self new a: (j at: 'a'); b: (j at: 'b'); c: (j at: 'c'); yourself!
----- Method: JsonDummyTestObject>>= (in category 'as yet unclassified') -----
= other
^ other class == self class and: [
a = other a and: [
b = other b and: [
c = other c]]]!
----- Method: JsonDummyTestObject>>a (in category 'accessing') -----
a
"Answer the value of a"
^ a!
----- Method: JsonDummyTestObject>>a: (in category 'accessing') -----
a: anObject
"Set the value of a"
a := anObject!
----- Method: JsonDummyTestObject>>b (in category 'accessing') -----
b
"Answer the value of b"
^ b!
----- Method: JsonDummyTestObject>>b: (in category 'accessing') -----
b: anObject
"Set the value of b"
b := anObject!
----- Method: JsonDummyTestObject>>c (in category 'accessing') -----
c
"Answer the value of c"
^ c!
----- Method: JsonDummyTestObject>>c: (in category 'accessing') -----
c: anObject
"Set the value of c"
c := anObject!
----- Method: JsonDummyTestObject>>jsonWriteOn: (in category 'as yet unclassified') -----
jsonWriteOn: s
Json renderInstanceVariables: {#a. #b. #c} of: self on: s
!
----- Method: Object>>asJsonString (in category '*JSON') -----
asJsonString
^ String streamContents: [:str |
self jsonWriteOn: str ]!
Object subclass: #SerializedJson
instanceVariableNames: 'jsonString'
classVariableNames: ''
poolDictionaries: ''
category: 'JSON'!
----- Method: SerializedJson class>>on: (in category 'instance creation') -----
on: aString
^self new
jsonString: aString;
yourself!
----- Method: SerializedJson>>jsonString (in category 'accessing') -----
jsonString
^jsonString
!
----- Method: SerializedJson>>jsonString: (in category 'accessing') -----
jsonString: aString
jsonString := aString
!
----- Method: SerializedJson>>jsonWriteOn: (in category 'json-writing') -----
jsonWriteOn: stream
stream nextPutAll: jsonString!
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