I started experimenting with the GraphQL wp api.
I am querying the menus. As for the documentation, the query is very long
I would expect that querying
{
menus
}
only would bring about all the data nested in menus, it does not.
Why is this? What is the way to getting all nested data in an object as to see what's in there?
Thank you for your time
The rule is that every "leaf" fields in a GraphQL query should be a Scalar something like Int , Boolean , String etc. So if the meuns field in the root Query type is a Scalar , it is a valid query and will return you something.
If not , you have to continue navigating the Menu type and pick the fields that you want to include in the GraphQL query such as :
{
menus {
id
createdDate
}
}
There is no wildcard that can represent all fields in current GraphQL spec.You have to explicitly declare all fields you want to select in the query.By looking at the GraphQL schema, you can know the available fields for each type. One of the tips is to rely on the GraphQL introspection system .It basically means that you can use some of the GraphQL client such as Altair, Graphiql, or GraphQL Playground etc. which most of them will have some auto-suggest function that will guide you to compose a query by suggesting you what fields are available to be included for a type .
P.S. A similar analogy to SQL is that there is no select * from foo , you have to explicitly define the columns that you want to select in the select clause such as select id,name,address from foo.
If you keep in mind that you're getting back a JSON object, you can think of your GraphQL query as defining the left-hand side of the response (this is intentional in how it was designed), e.g. just the keys. So unless there are null values, what you get back should exactly match the shape of the query.
If you want to see what can be queried, you need access to the schema itself. If it's a schema provided by someone else (looks like WordPress in this case), they should also have provided the means to explore and understand it.
That is the main feature of GraphQL, you can specify what data you need from a query. And because of that, you can't just query menus in that way, you need to specify every nested field in menus you need and only then it'll work :)
Related
I've got a bigquery import from a firestore database where I want to query on a particular field from a document. This was populated via the firestore-bigquery extension and the document data is stored as a JSON string.
I'm trying to use a WHERE clause in my query that uses one of the fields from the JSON data. However this doesn't seem to work.
My query is as follows:
SELECT json_extract(data,'$.title') as title,p
FROM `table`
left join unnest(json_extract_array(data, '$.tags')) as p
where json_extract(data,'$.title') = 'technology'
data is the JSON object and title is an attribute of all of the items. The above query will run but yield 'no results' (There are definitely results there for the title in question as they appear in the table preview).
I've tried using WHERE title = 'technology' as well but this returns an error that title is an unrecognized field (hence the json_extract).
From my research this should work as a standard SQL JSON query but doesn't seem to work on Bigquery. Does anyone know of a way around this?
All I can think of is if I put the results in another table, but I don't know if that's a workable solution as the data is updated via the extension on an update, so I would need to constantly refresh my second table as well.
Edit
I'm wondering if configuring a view would help with this? Though ultimately I would like to query this based on different parameters and the docs here https://cloud.google.com/bigquery/docs/views suggest you can't reference query parameters in a view
I've since managed to work this out, and will share the solution for anyone else with the same problem.
The solution was to use JSON_VALUE in the WHERE clause instead e.g:
where JSON_VALUE(data,'$.title') = 'technology';
I'm still not sure if this is the best way to do this in terms of performance and cost so I will wait to see if anyone else leaves a better answer.
I'm designing a RESTful API and I'm trying to work out how I could represent a predicate with OR an operator when querying for a resource.
For example if I had a resource Foo with a property Name, how would you search for all Foo resources with a name matching "Name1" OR "Name2"?
This is straight forward when it's an AND operator as I could do the following:
http://www.website.com/Foo?Name=Name1&Age=19
The other approach I've seen is to post the search in the body.
You will need to pick your own approach, but I can name few that seem to be pretty logical (although not without disadvantages):
Option 1.: Using | operator:
http://www.website.com/Foo?Name=Name1|Name2
Option 2.: Using modified query param to allow selection by one of the values from the set (list of possible comma-separated values):
http://www.website.com/Foo?Name_in=Name1,Name2
Option 3.: Using PHP-like notation to provide list instead of single string:
http://www.website.com/Foo?Name[]=Name1&Name[]=Name2
All of the above mentioned options have one huge advantage: they do not interfere with other query params.
But as I mentioned, pick your own approach and be consistent about it across your API.
Well one quick way to fixing that is to add an additional parameter that is identifying the relationship between your parameters wether they're an and or an or for example:
http://www.website.com/Foo?Name=Name1&Age=19&or=true
Or for much more complex queries just keep a single parameter and in it include your whole query by making up your own little query language and on the server side you would parse the whole string and extract the information and the statement.
What drawbacks can you think of if I design my REST API with query strings without parameter values? Like so:
http://host/path/to/page?edit
http://host/path/to/page?delete
http://host/path/to/page/+commentId?reply
Instead of e.g.:
http://host/api/edit?page=path/to/page
http://host/api/delete?page=path/to/page
http://host/api/reply?page=path/to/page&comment=commentId
( Edit: Any page-X?edit and page-X?delete links would trigger GET requests but wouldn't actually edit or delete the page. Instead, they show a page with a <form>, in which page-X can be edited, or a <form> with a Really delete page-X? confiramtion dialog. The actual edit/delete requests would be POST or DELETE requests. In the same manner as host/api/edit?page=path/to/page shows a page with an edit <form>. /Edit. )
Pleace note that ?action is not how query strings are usually formatted. Instead, they are usually formated like so: ?key=value;key2=v2;key3=v3
Moreover, sometimes I'd use URLs like this one:
http://host/path/to/page?delete;user=spammer
That is, I'd include a query string parameter with no value (delete) and one parameter with a value (user=spammer) (in order to delete all comments posted by the spammer)
My Web framework copes fine with query strings like ?reply. So I suppose that what I'm mostly wondering about, is can you think of any client side issues? Or any problems, should I decide to use another Web framework? (Do you know if the frameworks you use provides information on query strings without parameter values?)
(My understanding from reading http://labs.apache.org/webarch/uri/rfc/rfc3986.html is that the query string format I use is just fine, but what does that matter to all clients and server frameworks everywhere.)
(I currently use the Lift-Web framework. I've tested Play Framework too and it was possible to get hold of the value-less query strings parameters, so both Play and Lift-Web seems okay from my point of view.)
Here is a related question about query strings with no values. However, it deals with ASP.NET functions returning null in some cases: Access Query string parameters with no values in ASP.NET
Kind regards, Kaj-Magnus
Query parameters without value are no problem, but putting actions into the URI, in particular destructive ones, is.
Are you seriously thinking about "restful" design, and having a GET be a destructive action?
In the android Notes demo, it accepts the URI:
sUriMatcher.addURI(NotePad.AUTHORITY, "notes", NOTES);
sUriMatcher.addURI(NotePad.AUTHORITY, "notes/#", NOTE_ID);
Where the difference between notes and notes/# is that notes/# returns the note who's ID matches #.
However, the managedQuery() method that is used to get data from the content provider has the following parameters:
Parameters
uri The URI of the content provider to query.
projection List of columns to return.
selection SQL WHERE clause.
selectionArgs The arguments to selection, if any ?s are pesent
sortOrder SQL ORDER BY clause.
So, is there any particular cause for the design decision of providing a URI for that, rather than just using the selection parameter? Or is it just a matter of taste?
Thank you.
I thinks its so you can do more complex lookups without having to complicate your selections and arguments. For example in my project I have multiple tables but use the same selection and arguments. To filter content. By using the URI I don't have interpret the query, I can just switch on the URI. It.might be personal taste to begin with. But in more complex scenarios you appreciate the URI. You can also use * to match strings in the same.way you can with#.
I think it's mostly a matter of taste. IMHO, putting the id in the Uri is a little cleaner since you can make the id opaque rather than require the client to know that it actually represents a specific row id. For instance, you can pass a lookup key (like in the the Contacts API) rather than a specific row id.
In a custom ContentProvider I need to filter out some columns specified in the inputs. Given the text-oriented Android interfaces this is giving me a hard time.
For example the input on MyContentProvider.query() would effectively ask something like:
SELECT column_a, column_b FROM my_table WHERE column_a=1 AND column_b=red;
The problem is that at this particular MyContentProvider _column_b_ might not make any sense and would not be present in the table. Filtering the projection so that only relevant columns remain can be easily done since it's a String[]. However, filtering the String "where" (selection) and "selectionArgs" inputs for these columns is not trivial. If done properly it would become:
SELECT column_a FROM my_table WHERE column_a=1;
Otherwise one would get a SQLiteException "no such column".
So, is there any easy way to ignore or filter columns from such an sql statement or do I need to go and write some smart albeit very limited regexp parsing code for the selection part?
The reason I'm not getting the right inputs is because I maintain a custom ContentProvider as an interface to address, but I talk to multiple custom ContentProviders herein (in the background). One way or another, I would need to filter the selection somewhere.
Please note that I am not asking simply how to do a query or use the SELECT ... WHERE statement. However it concerns my implementation of the query() function.
Since you are extending your MyContentProvider with ContentProvider why don't you just overload the query() method?
Look at ContentProvider - Sharing Content using the ContentProvider for someone elses example on how to create a custom ContentProvider. You should have full control over what data you fetch from your SQLiteDatabase.
More importantly, look at the arguments provided to query(), as they contain the information you need to you in a way where you can dynamically build the query from what is passed into the method call.
Depending on if you can find a good query builder, you have an opportunity to build a small but powerful abstraction layer to build your queries, so that you minimize the amount of actual SQL that you write yourself.
Also, always remember to sanitize your inputs!