Every Beginner's Pain:

Have you ever had the zeal to learn Blockchain Programming and it was all fine until you started encountering errors? I can relate to this and understands it could go as far as making you lose interest in what you once had an interest in. As a matter of fact, the internet made it worst in a way that there are either countless assumed solutions with no known effect or no documentation about the issue.

Not to worry anymore...I have decided to try as much as possible to solve these known issues so as to make Blockchain programming more fun and appealing to as many that want to venture into it.

Follow carefully as we journey through this together.

PROBLEM 1:

SPDX License Identifier not provided in source file

This is a very basic error and requires less stress to solve. But before we do,"What is SPDX License Identifier?"

An SPDX License identifier is a simple way to state the license that applies to a source code or documentation file.

It consists of the following parts on one line:

• The ‘begin comment’ characters for the applicable programming language

• The characters SPDX-License-Identifier: with whitespace following the colon

• An SPDX license ID (e.g., Apache-2.0) or SPDX license expression

The SPDX License ID or expression is where the contract gets attached and the various ID's that exist can be found on the SPDX License List.

The SPDX License List is a list of commonly found licenses and exceptions used in free and open-source and other collaborative software or documentation. The purpose of the SPDX License List is to enable easy and efficient identification of such licenses and exceptions in an SPDX document, in source files, or elsewhere. The SPDX License List includes a standardized short identifier, full name, vetted license text including matching guidelines markup as appropriate, and a canonical permanent URL for each license and exception.

Well, in a nutshell, SPDX License Identifier is what developers can use to specify the license the contract uses. ( e.g. OpenZeppelin Contracts use MIT license). SPDX license identifiers should be added to the top of contract files.

Just like in the normal world, there's what we call management of Data(DBMS)appdynamics.com/topics/database-management-... such that every known data is tracked to a folder where it can be easily accessed, Likewise, SPDX License Identifier works in enabling the ease of accessing a smart contract(will write an article on this later).

How do we solve this issue?

Well from the above, an SPDX license identifier error can only be solved by specifying the license provider for the contract you are about to create above the contract declaration itself. You can check through a list of the identifiers here spdx.org/licenses

NOTE: Always add double-forward slashes indicating an import into your contract.