CodeIgniter APIs

CodeIgniter API development for mobile apps and integrations

We build REST APIs on CodeIgniter that mobile developers and partners can rely on: consistent JSON, clear errors, secure tokens, rate limits and documentation that matches the code.

  • REST on CodeIgniter 3 and 4
  • A team with 100+ mobile apps
  • Documented endpoints
Get a free quote See our work
What is included
  • Resource controllers
  • Consistent responses
  • Tokens and JWT
  • Filters for auth and throttling
  • Validation and pagination
  • Versioning and documentation
Get a free quote Reply within one business day. NDA on request.
The problem

API problems that reach us

Sooner or later a CodeIgniter application has to talk to something other than a browser. A mobile app needs to log users in and sync their data. A React or Vue front end wants JSON instead of rendered pages. A partner asks for an endpoint to place orders, or your warehouse system needs stock levels every few minutes.

CodeIgniter is well suited to this work because it adds so little overhead to each request. CodeIgniter 4 ships with resource controllers and a response trait made for APIs. CodeIgniter 3 has no built-in REST layer, though established libraries fill that gap. We build on both, and since our team also delivers mobile apps, we design APIs from the side of the consumer: what the app screen needs, in how many calls, and what happens when the network drops.

  • The app team is blocked

    Mobile developers are waiting for endpoints, or working against ones that return different shapes for the same thing. Every mismatch costs a round of messages and another app build.

  • An API that grew by accident

    Endpoints were added one at a time as controller methods that echo JSON. Some check the session, some check nothing, and errors come back as HTML pages with a success status.

  • No way to change it safely

    Old versions of the mobile app are still in use, so any change to a response could crash them. Without versioning you are afraid to improve anything.

  • Partners need access and limits

    A third party wants to integrate, and you need to give them credentials, restrict what they can see, cap how often they call and know what they did.

What we do

Inside a CodeIgniter REST API

An API is a promise to other developers. We write that promise down first, then build each layer so it holds under real use.

Resource controllers

On CodeIgniter 4, resource routes map HTTP verbs to list, show, create, update and delete methods, giving every resource the same predictable set of endpoints.

Consistent responses

The API response trait returns correct status codes and a uniform JSON envelope for success, validation failures, missing records and permission errors.

Tokens and JWT

Personal access tokens through Shield or signed JWTs with refresh, scoped per client, revocable from the admin panel and never stored in plain text.

Filters for auth and throttling

Route filters verify the token before any controller runs and apply rate limits per client or IP, answering with the right status when a limit is hit.

Validation and pagination

Named validation rules per endpoint with field-level error messages, plus paging, sorting and filtering that behave identically across resources.

Versioning and documentation

Versioned route groups so old app releases keep working, and an OpenAPI description with examples that is updated in the same commit as the code.

Typical projects

Typical API engagements

01

Mobile app backend on CodeIgniter 4

Login, profile, content, orders, push notification registration and file upload endpoints for a Flutter, Android or iOS app, with an admin panel in the same project.

02

REST layer for a running application

A REST layer added to a running CodeIgniter 3 or 4 application so a new front end or app can use the same data and rules without duplicating them.

03

Keyed access for partners

Keyed access for outside companies to create orders, check status and pull catalogs, with per-partner permissions, quotas and a usage log.

04

Webhooks and system sync

Endpoints that receive events from payment, shipping or messaging providers, verify signatures, store each event and process it in the background so the caller gets a fast answer.

In depth

How we design a CodeIgniter API that lasts

Agree the contract before coding

We write the endpoint list with the people who will consume it: paths, request bodies, response fields, error cases. That description, in OpenAPI format, becomes the shared reference. Mobile developers can generate mock responses and start work straight away, instead of waiting for the backend to be finished. It also exposes awkward screens early, such as a dashboard that would need nine calls, while changing the design costs nothing.

CodeIgniter 4 or CodeIgniter 3

For a new API we use CodeIgniter 4. ResourceController and the resource route method give a standard REST shape, the response trait handles status codes and formats, filters handle cross-cutting checks, and the Throttler class provides rate limiting without extra infrastructure. When the API must live inside a CodeIgniter 3 application, we add a REST controller library, keep API controllers in their own folder, and put shared logic in models or libraries so web and API paths cannot drift apart. Session-based checks are never reused for the API. Each API request authenticates by itself.

Authentication that fits the client

There is no single right token scheme. For your own mobile app, opaque access tokens stored hashed in the database are simple and can be revoked instantly when a phone is lost. Signed JWTs make sense once more than one service has to trust the same token and a lookup on every call is too slow. Pulling one back early is awkward, which is why ours expire quickly and are renewed through a refresh token. Partner integrations get keys tied to a client record with explicit permissions. Whatever the scheme, tokens travel in the Authorization header over HTTPS, and login endpoints are throttled more tightly than the rest.

Versioning from the first release

Mobile apps stay installed for years. We put the version in the route group from day one and treat a published response as frozen: fields may be added, never renamed or removed. A breaking change means a new version served alongside the old one, plus a way for the app to learn that it should update. This costs little at the start and is painful to retrofit.

Testing and observability

Every endpoint has feature tests covering the success case, validation failure, missing token and wrong permission. A Postman collection is kept for manual checks by your team. In production we log request IDs, response times and error rates per endpoint, so a slow query or a misbehaving client is visible before users complain. If your consumers include a larger product with queues and events, compare this with Laravel API development.

Process

From endpoint list to production API

  1. 1

    Talk to the consumers

    We talk to the app developers or partner about screens, data and offline behavior, and list the endpoints that follow from that.

  2. 2

    Contract draft

    An OpenAPI document with every path, field and error is reviewed by both sides and adjusted until the consumers sign off.

  3. 3

    Build with tests

    Endpoints are implemented in groups with feature tests, deployed to a staging URL the app team can point at straight away.

  4. 4

    Integration round

    We sit with the app or partner developers while they connect, fix mismatches quickly and tune payloads for slow networks.

  5. 5

    Production and monitoring

    Go-live with rate limits, logging and alerts in place, credentials issued per client, and documentation published where consumers can reach it.

Deliverables

What ships with the API

  • An OpenAPI document that matches the deployed endpoints
  • A Postman collection for manual testing
  • Feature tests for success and failure cases
  • Per-client credentials with revocation
  • Versioned routes ready for future changes
FAQ

What buyers ask about CodeIgniter APIs

Can you add a REST API to our existing CodeIgniter 3 application?
Yes. We add a REST controller library, create API controllers in a separate folder and reuse your existing models so business rules stay in one place. Authentication for the API is handled with tokens, independent of the web session, and nothing changes for current browser users.
Should our API use JWT or regular access tokens?
It depends on who calls it. For a single mobile app talking to one backend, database-backed access tokens are simpler and easy to revoke. JWT earns its place when several services need to verify tokens independently. You get our recommendation, with reasons, before the first endpoint is written.
How do you stop the API from being abused?
With several layers. Tokens are scoped and revocable, filters apply rate limits per client and per IP, login endpoints get stricter limits, input is validated on every call, and requests are logged so unusual patterns can be traced to a specific credential.
What documentation do our app developers receive?
A full reference, delivered with the code. You get an OpenAPI description with example requests and responses, rendered as browsable pages, plus a Postman collection. It is updated with every change so it does not fall behind the code.
What happens to old app versions when the API changes?
They keep working. Endpoints are versioned in the URL, published responses only gain fields, and a breaking change is released as a new version beside the old one. We can also add a minimum-version check so the app can prompt users to update.
Can you build the mobile app as well as the API?
Yes. Our mobile team builds on Flutter, Android, iOS and React Native, and having both sides in one company removes most integration friction. See mobile app API integration for how the two teams work together.
Is CodeIgniter fast enough for a busy API?
For most business workloads, yes. The framework adds little overhead per request, so response time is dominated by your queries. We index for the real access patterns, cache what is safe to cache and measure under load before launch.
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Need an API on CodeIgniter?

Tell us who will consume the API, a mobile app, a front end or a partner, and what it has to do. Within one business day we send back a first list of endpoints and our questions, and the quote is free.

  • Free consultation and quote
  • NDA on request
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  • Reply within one business day
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