Search parameter in Rest API - Step-by-Step Execution

Concept Flow - Search parameter

Client sends request with search parameter

↓

Server receives request

↓

Server extracts search parameter

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Server filters data based on parameter

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Server sends filtered data back

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Client receives and displays results

The client sends a request with a search parameter; the server extracts it, filters data accordingly, and returns the filtered results.

Execution Sample

Rest API

GET /api/items?search=apple

// Server extracts 'search' parameter
// Filters items containing 'apple'
// Returns filtered list

This example shows a client requesting items containing 'apple' using a search parameter in the URL.

Execution Table

Step	Action	Search Parameter Extracted	Data Filtered	Response Sent
1	Client sends GET request with ?search=apple	search=apple	No	No
2	Server receives request	search=apple	No	No
3	Server extracts 'search' parameter	search=apple	No	No
4	Server filters data for items containing 'apple'	search=apple	Filtered list with 'apple'	No
5	Server sends filtered data back	search=apple	Filtered list with 'apple'	Yes
6	Client receives and displays results	search=apple	Filtered list with 'apple'	Yes

💡 Response sent after filtering data based on search parameter.

Variable Tracker

Variable	Start	After Step 3	After Step 4	Final
search_parameter	None	"apple"	"apple"	"apple"
filtered_data	All items	All items	Items containing 'apple'	Items containing 'apple'
response_sent	False	False	False	True

Key Moments - 2 Insights

Why does the server need to extract the search parameter before filtering?

Because the server must know what to look for in the data; extraction happens at Step 3 in the execution table before filtering at Step 4.

What happens if the search parameter is missing?

The server might return all data or no data depending on implementation; in this trace, filtering only happens after extracting a valid parameter at Step 3.

Visual Quiz - 3 Questions

Look at the execution table, at which step does the server filter the data?

A Step 4

B Step 3

C Step 2

D Step 5

💡 Hint

Check the 'Data Filtered' column in the execution table to see when filtering happens.

According to the variable tracker, what is the value of 'response_sent' after Step 4?

A True

B False

C None

D Unknown

💡 Hint

Look at the 'response_sent' row and the 'After Step 4' column in the variable tracker.

If the search parameter was 'banana' instead of 'apple', what would change in the execution table?

A No changes at all

B The response would be sent earlier

C The 'Search Parameter Extracted' would be 'banana' and filtered data would contain 'banana'

D The client would not receive any data

💡 Hint

Refer to the 'Search Parameter Extracted' and 'Data Filtered' columns in the execution table.

Concept Snapshot

Search parameter in REST API:
- Sent as query string (e.g., ?search=term)
- Server extracts parameter from request
- Server filters data based on parameter
- Server returns filtered results
- Client displays filtered data

Full Transcript

In a REST API, a search parameter is sent by the client as part of the URL query string. The server receives the request and extracts this parameter to understand what the client wants to find. Then, the server filters its data to include only items matching the search term. Finally, the server sends back the filtered data, and the client shows these results. This flow ensures the client gets only relevant information based on their search.

Practice

1.

What is the main purpose of a search parameter in a REST API URL?

easy

A. To change the API server address

B. To filter the data returned by the API

C. To add security to the API

D. To format the API response as XML

Solution

1. Step 1: Understand what search parameters do

   Search parameters are added to the URL to specify what data you want from the API.

2. Step 2: Identify the purpose of filtering

   Filtering means selecting only the data that matches your criteria, which is what search parameters do.

3. Final Answer:

   To filter the data returned by the API -> Option B

4. Quick Check:

   Search parameter = filter data [OK]

Hint: Search parameters filter data in API URLs [OK]

Common Mistakes:

• Thinking search parameters change server address
• Confusing search parameters with security tokens
• Assuming search parameters format response

2.

Which of the following is the correct way to add a search parameter named name with value alice to a REST API URL?

https://api.example.com/users

easy

A. https://api.example.com/users#name=alice

B. https://api.example.com/users/name=alice

C. https://api.example.com/users?name=alice

D. https://api.example.com/users&name=alice

Solution

1. Step 1: Recall the syntax for search parameters

   Search parameters start with a question mark (?) after the base URL.

2. Step 2: Check the correct separator and format

   The parameter is added as ?name=alice. Using & or # or slashes is incorrect here.

3. Final Answer:

   https://api.example.com/users?name=alice -> Option C

4. Quick Check:

   Use ? before first parameter [OK]

Hint: First parameter starts with ? in URL [OK]

Common Mistakes:

• Using & instead of ? for first parameter
• Using # which is for anchors, not parameters
• Adding parameters as path segments

3.

What will be the full URL to search for users with age 30 and city as NY?

Base URL: https://api.example.com/users

medium

A. https://api.example.com/users?age=30&city=NY

B. https://api.example.com/users?age=30?city=NY

C. https://api.example.com/users&age=30&city=NY

D. https://api.example.com/users#age=30&city=NY

Solution

1. Step 1: Add first parameter with ?

   The first search parameter starts with a question mark: ?age=30.

2. Step 2: Add second parameter with &

   Additional parameters use & to separate: &city=NY.

3. Final Answer:

   https://api.example.com/users?age=30&city=NY -> Option A

4. Quick Check:

   First ? then & for multiple parameters [OK]

Hint: Use ? for first, & for others in URL [OK]

Common Mistakes:

• Using ? for every parameter
• Using & before first parameter
• Using # which is for anchors

4.

Identify the error in this URL with search parameters:

https://api.example.com/products?category=books&price=20?sort=asc

medium

A. Using two question marks (?) for parameters

B. Missing & between parameters

C. Using = instead of : in parameters

D. Parameters should be in the URL path, not query

Solution

1. Step 1: Check parameter separators

   Only the first parameter uses ?, others must use &.

2. Step 2: Identify the error in the URL

   The URL incorrectly uses a second ? before sort=asc instead of &.

3. Final Answer:

   Using two question marks (?) for parameters -> Option A

4. Quick Check:

   Only one ? allowed, others use & [OK]

Hint: Only one ? in URL, then & for others [OK]

Common Mistakes:

• Using multiple ? instead of &
• Confusing = with : in parameters
• Thinking parameters belong in URL path

5.

You want to search a REST API for books with author as John and year greater than 2010. Which URL correctly uses search parameters to do this?

hard

A. https://api.example.com/books?author=John&year>2010

B. https://api.example.com/books?author=John&year=2010>

C. https://api.example.com/books?author=John&year=gt2010

D. https://api.example.com/books?author=John&year_gt=2010

Solution

1. Step 1: Understand how to express 'greater than' in search parameters

   REST APIs often use suffixes like _gt for 'greater than' in parameters.

2. Step 2: Check each option for correct syntax

   https://api.example.com/books?author=John&year_gt=2010 uses year_gt=2010, which is a common and correct way to express this filter.

3. Final Answer:

   https://api.example.com/books?author=John&year_gt=2010 -> Option D

4. Quick Check:

   Use _gt suffix for greater than filters [OK]

Hint: Use _gt suffix for 'greater than' in parameters [OK]

Common Mistakes:

• Using > directly in URL parameter
• Placing operators after values
• Confusing parameter syntax for filters