I have an xml file of the form:
<property name="foo" value="this is a long value">stuff</property>
There are many properties but I want to match the one with name foo and then replace its value attribute with something else as so:
<property name="foo" value="yet another long value">stuff</property>
I was thinking to write a regular expression to match everything after "foo" to the end of the tag ( ">" ) and replace that, but I can't seem to get the syntax right.
I'm trying to do this using sed, if that's any help.
/property name=\"foo\" value=\"([^\"]*)\"/
Then just replace the first submatch with the new value of your wishing.
You probably don't want to use a regex for manipulating an xml file. Please instead consider xslt, which is aware of xml rules and won't cause your transformed document to become malformed.
If you're doing this in the context of a browser, you could create a throwaway DOM node containing the XML and just walk that to replace attribute values.
This function will call a callback on every child node:
const walkDOM = (node, callback) => {
callback(node);
[...node.children].forEach(child => {
walkDOM(child, callback)
});
}
You can then use this to update any attributes matching conditions you'd like (here replacing any, assuming you have an XML string called svgXml:
const containerEl = document.createElement('div');
containerEl.innerHTML = svgXml;
walkDOM(containerEl, el => {
const attributes = [...el.attributes];
attributes.forEach(attr => {
if (attr.name === 'foo' && attr.value === 'this is a long value']) {
attr.value = 'yet another long value';
}
});
});
const outputSvgXml = containerEl.innerHTML;
Of course you could further optimize this by using querySelectorAll(property) to only walk <property> nodes, etc.
I found this useful for updating an SVG while taking advantage of the browser's robustness.
Related
I've got a Node module file containing about 100 exported methods, which looks something like this:
exports.methodOne = async user_id => {
// other method contents
};
exports.methodTwo = async user_id => {
// other method contents
fooMethod();
};
exports.methodThree = async user_id => {
// other method contents
fooMethod();
};
Goal: What I'd like to do is figure out how to grab the name of any method which contains a call to fooMethod, and return the correct method names: methodTwo and methodThree. I wrote a regex which gets kinda close:
exports\.(\w+).*(\n.*?){1,}fooMethod
Problem: using my example code from above, though, it would effectively match methodOne and methodThree because it finds the first instance of export and then the first instance of fooMethod and goes on from there. Here's a regex101 example.
I suspect I could make use of lookaheads or lookbehinds, but I have little experience with those parts of regex, so any guidance would be much appreciated!
Edit: Turns out regex is poorly-suited for this type of task. #ctcherry advised using a parser, and using that as a springboard, I was able to learn about Abstract Syntax Trees (ASTs) and the recast tool which lets you traverse the tree after using various tools (acorn and others) to parse your code into tree form.
With these tools in hand, I successfully built a script to parse and traverse my node app's files, and was able to find all methods containing fooMethod as intended.
Regex isn't the best tool to tackle all the parts of this problem, ideally we could rely on something higher level, a parser.
One way to do this is to let the javascript parse itself during load and execution. If your node module doesn't include anything that would execute on its own (or at least anything that would conflict with the below), you can put this at the bottom of your module, and then run the module with node mod.js.
console.log(Object.keys(exports).filter(fn => exports[fn].toString().includes("fooMethod(")));
(In the comments below it is revealed that the above isn't possible.)
Another option would be to use a library like https://github.com/acornjs/acorn (there are other options) to write some other javascript that parses your original target javascript, then you would have a tree structure you could use to perform your matching and eventually return the function names you are after. I'm not an expert in that library so unfortunately I don't have sample code for you.
This regex matches (only) the method names that contain a call to fooMethod();
(?<=exports\.)\w+(?=[^{]+\{[^}]+fooMethod\(\)[^}]+};)
See live demo.
Assuming that all methods have their body enclosed within { and }, I would make an approach to get to the final regex like this:
First, find a regex to get the individual methods. This can be done using this regex:
exports\.(\w+)(\s|.)*?\{(\s|.)*?\}
Next, we are interested in those methods that have fooMethod in them before they close. So, look for } or fooMethod.*}, in that order. So, let us name the group searching for fooMethod as FOO and the name of the method calling it as METH. When we iterate the matches, if group FOO is present in a match, we will use the corresponding METH group, else we will reject it.
exports\.(?<METH>\w+)(\s|.)*?\{(\s|.)*?(\}|(?<FOO>fooMethod)(\s|.)*?\})
Explanation:
exports\.(?<METH>\w+): Till the method name (you have already covered this)
(\s|.)*?\{(\s|.)*?: Some code before { and after, non-greedy so that the subsequent group is given preference
(\}|(?<FOO>fooMethod)(\s|.)*?\}): This has 2 parts:
\}: Match the method close delimiter, OR
(?<FOO>fooMethod)(\s|.)*?\}): The call to fooMethod followed by optional code and method close delimiter.
Here's a JavaScript code that demostrates this:
let p = /exports\.(?<METH>\w+)(\s|.)*?\{(\s|.)*?(\}|(?<FOO>fooMethod)(\s|.)*?\})/g
let input = `exports.methodOne = async user_id => {
// other method contents
};
exports.methodTwo = async user_id => {
// other method contents
fooMethod();
};
exports.methodThree = async user_id => {
// other method contents
fooMethod();
};';`
let match = p.exec( input );
while( match !== null) {
if( match.groups.FOO !== undefined ) console.log( match.groups.METH );
match = p.exec( input )
}
Hello I want to extract JSON from below input string.
I have tried bellow regex in java and it is working fine,
private static final Pattern shortcode_media = Pattern.compile("\"shortcode_media\":(\\{.+\\})");
I want in regex for dart.
Input String
<script type="text/javascript">window.__initialDataLoaded(window._sharedData);</script><script type="text/javascript">window.__additionalDataLoaded('/p/B9fphP5gBeG/',{"graphql":{"shortcode_media":{"__typename":"GraphSidecar","id":"2260708142683789190","shortcode":"B9fphP5gBeG","dimensions":{"height":1326,"width":1080}}}});</script><script type="text/javascript">
<script type="text/javascript">window.__initialDataLoaded(window._newData);</script><script type="text/javascript">window._newData('/p/B9fphP5gBeG/',{"graphql":{"post":{"__typename":"id","id":"2260708142683789190","new_code":"B9fphP5gBeG"}}});</script><script type="text/javascript">
(function(){
function normalizeError(err) {
var errorInfo = err.error || {};
var getConfigProp = function(propName, defaultValueIfNotTruthy) {
var propValue = window._sharedData && window._sharedData[propName];
return propValue ? propValue : defaultValueIfNotTruthy;
};
return {}
}
)
Expected json
{"graphql":{"shortcode_media":{"__typename":"GraphSidecar","id":"2260708142683789190","shortcode":"B9fphP5gBeG","dimensions":{"height":1326,"width":1080}}}}
Note: There are multiple json string in input string, i need json of shortcode_media tag
please use
void main() {
String json = '''
{"graphql":
{"shortcode_media":{"__typename":"GraphSidecar","id":"2260708142683789190","shortcode":"B9fphP5gBeG","dimensions":{"height":1326,"width":1080}}},
"abc":{"def":"test"}
}
''';
RegExp regExp = new RegExp(
"\"shortcode_media\":(\\{.+\\})",
caseSensitive: false,
multiLine: false,
);
print(regExp.stringMatch(json).toString());
}
output
"shortcode_media":{"__typename":"GraphSidecar","id":"2260708142683789190","shortcode":"B9fphP5gBeG","dimensions":{"height":1326,"width":1080}}}
Dartpad
The corresponding Dart RegExp would be:
static final RegExp shortcodeMedia = RegExp(r'"shortcode_media":(\{.+\})");
It does not work, though. JSON is not a regular language, so you can't parse it using regular expressions.
The value of "shortcode_media" in your example JSON ends with several } characters. The RegExp will stop the match at the third of those, even though the second } is the one matching the leading {. If your JSON text contains any further values after the shortcode_media entry, those might be included as well.
Stopping at the first } would also be too short.
If someone reorders the JSON source code to the equivalent
"shortcode_media":{"dimensions":{"height":1326,"width":1080},"__typename":"GraphSidecar","id":"2260708142683789190","shortcode":"B9fphP5gBeG"}
(that is, putting the "dimensions" entry first), then you would only capture until the end of the dimensions block.
I would recommend either using a proper JSON parser, or at least improving the RegExp to be able to handle a single nested JSON object - since you seem to already know that it will happen.
Such a RegExp could be:
RegExp(r'"shortcode_media":(\{(?:[^{}]*(?:\{.*?\})?)*?\})')
This RegExp will capture the correct number of braces for the example code, but still won't work if there are more nested JSON objects. Only a real parser can handle the general case correctly.
I struggle to find a solution for what is probably pretty simple, and despite I crawl a lot of questions, I can't manage to make it work.
Here are 2 HTML elements:
Test1
Test2
I want to get ONLY the content of the 1st element's href property (#content1). It must match because the html element contains no "onclick" property.
This regex works for matching the 1st element only:
^<a href="#"((?!onclick).)*$
but I can't figure out how to get the HREF content.
I've tried this:
^<a href="#(.*)"((?!onclick).)*$
but in this case, both elements are matching.
Thanks for your help !
I strongly suggest that you should do that in two steps. For one thing, parsing arbitrary html with a regexp is a notoriously slippery and winding road. For the other: there is no achievement in doing everything with one illegible regex.
And there's more to it: "contains no "onclick" attribute" is not the same as "href attribute is not directly followed by onclick attribute". So, a one-regex-solution would be either very complicated or very fragile (html tags have arbitrary attributes order).
var a = [
'Test1',
'Test2'
];
console.log(
a.filter(i => i.match(/onclick/i) == null)
.map(i => i.match(/href="([^"]+)"/i)[1]
)
This assumes that your href attribute values are valid and do not contain quotes (which is, of course, technically possible).
Regex is not made for this. JavaScript would work better. This code will store an array of the hrefs matching your requirements in the variable hrefArray.
var hrefArray = [];
for (var elem of document.getElementsByTagName('a')) {
if (elem.onclick) hrefArray.push(elem.href)
}
An example with your HTML is in the snippet below:
var hrefArray = [];
for (var elem of document.getElementsByTagName('a')) {
if (elem.onclick) hrefArray.push(elem.href)
}
console.log(hrefArray);
body {
background-color: gray;
}
Test1
Test2
I have a JSON object something like below from which i wanted to strip out sensitive information like password, mobile no, etc. using Regular Expressions,
Example JSON
{
"username":"abc",
"password":"xyz123",
"Security":{
"SecurityQuestion":"what is your first pet name",
"SecurityAnswer": "snoopy"
}
}
From the above JSON object, I wanted to strip out sensitive information like "password" and "SecurityAnswer". I tried various regular expression patterns but it was removing only either any one of the item.
I need help or guidance on how to construct a regular expression, in which i can include any names in the expression and then those fields will be stripped out of the JSON.
Expected Output:
{
"username":"abc",
"Security":{
"SecurityQuestion":"what is your first pet name"
}
}
Note: If a password is the last property, then the expression should be able to remove the comma (,) also from the previous property.
I tried the expression from Regex remove json property with various combinations but none were working as per my requirement.
If you want to get values from JSON, you don't need to use regex and make a very complex regular expression.
var data = {
"username":"abc",
"password":"xyz123",
"Security":{
"SecurityQuestion":"what is your first pet name",
"SecurityAnswer": "snoopy"
}
}
That is your object, now if you want to retrieve the data simply treat it like a json.
function retrieveData( Obj ) {
return {
username: Obj.username,
Security:{
SecurityQuestion: Obj.Security.SecurityQuestion
}
}
}
var extractedData = retrieveData(data);
I'm using selenium RC and I would like, for example, to get all the links elements with attribute href that match:
http://[^/]*\d+com
I would like to use:
sel.get_attribute( '//a[regx:match(#href, "http://[^/]*\d+.com")]/#name' )
which would return a list of the name attribute of all the links that match the regex.
(or something like it)
thanks
The answer above is probably the right way to find ALL of the links that match a regex, but I thought it'd also be helpful to answer the other part of the question, how to use regex in Xpath locators. You need to use the regex matches() function, like this:
xpath=//div[matches(#id,'che.*boxes')]
(this, of course, would click the div with 'id=checkboxes', or 'id=cheANYTHINGHEREboxes')
Be aware, though, that the matches function is not supported by all native browser implementations of Xpath (most conspicuously, using this in FF3 will throw an error: invalid xpath[2]).
If you have trouble with your particular browser (as I did with FF3), try using Selenium's allowNativeXpath("false") to switch over to the JavaScript Xpath interpreter. It'll be slower, but it does seem to work with more Xpath functions, including 'matches' and 'ends-with'. :)
You can use the Selenium command getAllLinks to get an array of the ids of links on the page, which you could then loop through and check the href using the getAttribute, which takes the locator followed by an # and the attribute name. For example in Java this might be:
String[] allLinks = session().getAllLinks();
List<String> matchingLinks = new ArrayList<String>();
for (String linkId : allLinks) {
String linkHref = selenium.getAttribute("id=" + linkId + "#href");
if (linkHref.matches("http://[^/]*\\d+.com")) {
matchingLinks.add(link);
}
}
A possible solution is to use sel.get_eval() and write a JS script that returns a list of the links. something like the following answer:
selenium: Is it possible to use the regexp in selenium locators
Here's some alternate methods as well for Selenium RC. These aren't pure Selenium solutions, they allow interaction with your programming language data structures and Selenium.
You can also get get HTML page source, then regular expression the source to return a match set of links. Use regex grouping to separate out URLs, link text/ID, etc. and you can then pass them back to selenium to click on or navigate to.
Another method is get HTML page source or innerHTML (via DOM locators) of a parent/root element then convert the HTML to XML as DOM object in your programming language. You can then traverse the DOM with desired XPath (with regular expression or not), and obtain a nodeset of only the links of interest. From their parse out the link text/ID or URL and you can pass back to selenium to click on or navigate to.
Upon request, I'm providing examples below. It's mixed languages since the post didn't appear to be language specific anyways. I'm just using what I had available to hack together for examples. They aren't fully tested or tested at all, but I've worked with bits of the code before in other projects, so these are proof of concept code examples of how you'd implement the solutions I just mentioned.
//Example of element attribute processing by page source and regex (in PHP)
$pgSrc = $sel->getPageSource();
//simple hyperlink extraction via regex below, replace with better regex pattern as desired
preg_match_all("/<a.+href=\"(.+)\"/",$pgSrc,$matches,PREG_PATTERN_ORDER);
//$matches is a 2D array, $matches[0] is array of whole string matched, $matches[1] is array of what's in parenthesis
//you either get an array of all matched link URL values in parenthesis capture group or an empty array
$links = count($matches) >= 2 ? $matches[1] : array();
//now do as you wish, iterating over all link URLs
//NOTE: these are URLs only, not actual hyperlink elements
//Example of XML DOM parsing with Selenium RC (in Java)
String locator = "id=someElement";
String htmlSrcSubset = sel.getEval("this.browserbot.findElement(\""+locator+"\").innerHTML");
//using JSoup XML parser library for Java, see jsoup.org
Document doc = Jsoup.parse(htmlSrcSubset);
/* once you have this document object, can then manipulate & traverse
it as an XML/HTML node tree. I'm not going to go into details on this
as you'd need to know XML DOM traversal and XPath (not just for finding locators).
But this tutorial URL will give you some ideas:
http://jsoup.org/cookbook/extracting-data/dom-navigation
the example there seems to indicate first getting the element/node defined
by content tag within the "document" or source, then from there get all
hyperlink elements/nodes and then traverse that as a list/array, doing
whatever you want with an object oriented approach for each element in
the array. Each element is an XML node with properties. If you study it,
you'd find this approach gives you the power/access that WebDriver/Selenium 2
now gives you with WebElements but the example here is what you can do in
Selenium RC to get similar WebElement kind of capability
*/
Selenium's By.Id and By.CssSelector methods do not support Regex and By.XPath only does where XPath 2.0 is enabled. If you want to use Regex, you can do something like this:
void MyCallingMethod(IWebDriver driver)
{
//Search by ID:
string attrName = "id";
//Regex = 'a number that is 1-10 digits long'
string attrRegex= "[0-9]{1,10}";
SearchByAttribute(driver, attrName, attrRegex);
}
IEnumerable<IWebElement> SearchByAttribute(IWebDriver driver, string attrName, string attrRegex)
{
List<IWebElement> elements = new List<IWebElement>();
//Allows spaces around equal sign. Ex: id = 55
string searchString = attrName +"\\s*=\\s*\"" + attrRegex +"\"";
//Search page source
MatchCollection matches = Regex.Matches(driver.PageSource, searchString, RegexOptions.IgnoreCase);
//iterate over matches
foreach (Match match in matches)
{
//Get exact attribute value
Match innerMatch = Regex.Match(match.Value, attrRegex);
cssSelector = "[" + attrName + "=" + attrRegex + "]";
//Find element by exact attribute value
elements.Add(driver.FindElement(By.CssSelector(cssSelector)));
}
return elements;
}
Note: this code is untested. Also, you can optimize this method by figuring out a way to eliminate the second search.