How to fix ESP-IDF fatal error: cJSON.h: No such file or directory

Problem

When building an ESP-IDF project, you may encounter the following error:

/home/user/MyProject/main/main.cpp:10:10: fatal error: cJSON.h: No such file or directory
   10 | #include <cJSON.h>
      |          ^~~~~~~~~
compilation terminated.

Solution

You need to ensure that the json component is included in your project. This can be done by modifying your main/CMakeLists.txt file to include the json component as a dependency.

You can do this by adding the REQUIRES json line in your idf_component_register function. Here’s how to modify your main/CMakeLists.txt file:

idf_component_register(
    SRCS "main.cpp"
    INCLUDE_DIRS "../include"
    REQUIRES json
)

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